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-rw-r--r--hw/arm/Kconfig9
-rw-r--r--hw/arm/meson.build1
-rw-r--r--hw/arm/mps2.c97
-rw-r--r--hw/arm/npcm7xx.c532
-rw-r--r--hw/arm/npcm7xx_boards.c197
-rw-r--r--hw/arm/xlnx-versal-virt.c2
-rw-r--r--hw/mem/meson.build1
-rw-r--r--hw/mem/npcm7xx_mc.c84
-rw-r--r--hw/misc/a9scu.c59
-rw-r--r--hw/misc/meson.build4
-rw-r--r--hw/misc/npcm7xx_clk.c266
-rw-r--r--hw/misc/npcm7xx_gcr.c269
-rw-r--r--hw/misc/trace-events8
-rw-r--r--hw/nvram/meson.build1
-rw-r--r--hw/nvram/npcm7xx_otp.c440
-rw-r--r--hw/ssi/meson.build1
-rw-r--r--hw/ssi/npcm7xx_fiu.c572
-rw-r--r--hw/ssi/trace-events11
-rw-r--r--hw/timer/armv7m_systick.c8
-rw-r--r--hw/timer/meson.build1
-rw-r--r--hw/timer/npcm7xx_timer.c543
-rw-r--r--hw/timer/trace-events5
22 files changed, 3065 insertions, 46 deletions
diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
index bc3a423940..f303c6bead 100644
--- a/hw/arm/Kconfig
+++ b/hw/arm/Kconfig
@@ -355,6 +355,15 @@ config XLNX_VERSAL
     select VIRTIO_MMIO
     select UNIMP
 
+config NPCM7XX
+    bool
+    select A9MPCORE
+    select ARM_GIC
+    select PL310  # cache controller
+    select SERIAL
+    select SSI
+    select UNIMP
+
 config FSL_IMX25
     bool
     select IMX
diff --git a/hw/arm/meson.build b/hw/arm/meson.build
index 8480b7f37d..be39117b9b 100644
--- a/hw/arm/meson.build
+++ b/hw/arm/meson.build
@@ -13,6 +13,7 @@ arm_ss.add(when: 'CONFIG_MICROBIT', if_true: files('microbit.c'))
 arm_ss.add(when: 'CONFIG_MUSICPAL', if_true: files('musicpal.c'))
 arm_ss.add(when: 'CONFIG_NETDUINO2', if_true: files('netduino2.c'))
 arm_ss.add(when: 'CONFIG_NETDUINOPLUS2', if_true: files('netduinoplus2.c'))
+arm_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx.c', 'npcm7xx_boards.c'))
 arm_ss.add(when: 'CONFIG_NSERIES', if_true: files('nseries.c'))
 arm_ss.add(when: 'CONFIG_SX1', if_true: files('omap_sx1.c'))
 arm_ss.add(when: 'CONFIG_CHEETAH', if_true: files('palm.c'))
diff --git a/hw/arm/mps2.c b/hw/arm/mps2.c
index 4ee5c38459..5d47160850 100644
--- a/hw/arm/mps2.c
+++ b/hw/arm/mps2.c
@@ -15,6 +15,8 @@
  * as seen by the guest depend significantly on the FPGA image.
  * We model the following FPGA images:
  *  "mps2-an385" -- Cortex-M3 as documented in ARM Application Note AN385
+ *  "mps2-an386" -- Cortex-M4 as documented in ARM Application Note AN386
+ *  "mps2-an500" -- Cortex-M7 as documented in ARM Application Note AN500
  *  "mps2-an511" -- Cortex-M3 'DesignStart' as documented in AN511
  *
  * Links to the TRM for the board itself and to the various Application
@@ -48,6 +50,8 @@
 
 typedef enum MPS2FPGAType {
     FPGA_AN385,
+    FPGA_AN386,
+    FPGA_AN500,
     FPGA_AN511,
 } MPS2FPGAType;
 
@@ -55,6 +59,9 @@ struct MPS2MachineClass {
     MachineClass parent;
     MPS2FPGAType fpga_type;
     uint32_t scc_id;
+    bool has_block_ram;
+    hwaddr ethernet_base;
+    hwaddr psram_base;
 };
 typedef struct MPS2MachineClass MPS2MachineClass;
 
@@ -82,6 +89,8 @@ typedef struct MPS2MachineState MPS2MachineState;
 
 #define TYPE_MPS2_MACHINE "mps2"
 #define TYPE_MPS2_AN385_MACHINE MACHINE_TYPE_NAME("mps2-an385")
+#define TYPE_MPS2_AN386_MACHINE MACHINE_TYPE_NAME("mps2-an386")
+#define TYPE_MPS2_AN500_MACHINE MACHINE_TYPE_NAME("mps2-an500")
 #define TYPE_MPS2_AN511_MACHINE MACHINE_TYPE_NAME("mps2-an511")
 
 DECLARE_OBJ_CHECKERS(MPS2MachineState, MPS2MachineClass,
@@ -139,13 +148,14 @@ static void mps2_common_init(MachineState *machine)
      * tradeoffs. For QEMU they're all just RAM, though. We arbitrarily
      * call the 16MB our "system memory", as it's the largest lump.
      *
-     * Common to both boards:
-     *  0x21000000..0x21ffffff : PSRAM (16MB)
-     * AN385 only:
+     * AN385/AN386/AN511:
+     *  0x21000000 .. 0x21ffffff : PSRAM (16MB)
+     * AN385/AN386/AN500:
      *  0x00000000 .. 0x003fffff : ZBT SSRAM1
      *  0x00400000 .. 0x007fffff : mirror of ZBT SSRAM1
      *  0x20000000 .. 0x203fffff : ZBT SSRAM 2&3
      *  0x20400000 .. 0x207fffff : mirror of ZBT SSRAM 2&3
+     * AN385/AN386 only:
      *  0x01000000 .. 0x01003fff : block RAM (16K)
      *  0x01004000 .. 0x01007fff : mirror of above
      *  0x01008000 .. 0x0100bfff : mirror of above
@@ -155,21 +165,17 @@ static void mps2_common_init(MachineState *machine)
      *  0x00400000 .. 0x007fffff : ZBT SSRAM1
      *  0x20000000 .. 0x2001ffff : SRAM
      *  0x20400000 .. 0x207fffff : ZBT SSRAM 2&3
+     * AN500 only:
+     *  0x60000000 .. 0x60ffffff : PSRAM (16MB)
      *
-     * The AN385 has a feature where the lowest 16K can be mapped
+     * The AN385/AN386 has a feature where the lowest 16K can be mapped
      * either to the bottom of the ZBT SSRAM1 or to the block RAM.
      * This is of no use for QEMU so we don't implement it (as if
      * zbt_boot_ctrl is always zero).
      */
-    memory_region_add_subregion(system_memory, 0x21000000, machine->ram);
+    memory_region_add_subregion(system_memory, mmc->psram_base, machine->ram);
 
-    switch (mmc->fpga_type) {
-    case FPGA_AN385:
-        make_ram(&mms->ssram1, "mps.ssram1", 0x0, 0x400000);
-        make_ram_alias(&mms->ssram1_m, "mps.ssram1_m", &mms->ssram1, 0x400000);
-        make_ram(&mms->ssram23, "mps.ssram23", 0x20000000, 0x400000);
-        make_ram_alias(&mms->ssram23_m, "mps.ssram23_m",
-                       &mms->ssram23, 0x20400000);
+    if (mmc->has_block_ram) {
         make_ram(&mms->blockram, "mps.blockram", 0x01000000, 0x4000);
         make_ram_alias(&mms->blockram_m1, "mps.blockram_m1",
                        &mms->blockram, 0x01004000);
@@ -177,6 +183,17 @@ static void mps2_common_init(MachineState *machine)
                        &mms->blockram, 0x01008000);
         make_ram_alias(&mms->blockram_m3, "mps.blockram_m3",
                        &mms->blockram, 0x0100c000);
+    }
+
+    switch (mmc->fpga_type) {
+    case FPGA_AN385:
+    case FPGA_AN386:
+    case FPGA_AN500:
+        make_ram(&mms->ssram1, "mps.ssram1", 0x0, 0x400000);
+        make_ram_alias(&mms->ssram1_m, "mps.ssram1_m", &mms->ssram1, 0x400000);
+        make_ram(&mms->ssram23, "mps.ssram23", 0x20000000, 0x400000);
+        make_ram_alias(&mms->ssram23_m, "mps.ssram23_m",
+                       &mms->ssram23, 0x20400000);
         break;
     case FPGA_AN511:
         make_ram(&mms->blockram, "mps.blockram", 0x0, 0x40000);
@@ -192,6 +209,8 @@ static void mps2_common_init(MachineState *machine)
     armv7m = DEVICE(&mms->armv7m);
     switch (mmc->fpga_type) {
     case FPGA_AN385:
+    case FPGA_AN386:
+    case FPGA_AN500:
         qdev_prop_set_uint32(armv7m, "num-irq", 32);
         break;
     case FPGA_AN511:
@@ -228,6 +247,8 @@ static void mps2_common_init(MachineState *machine)
 
     switch (mmc->fpga_type) {
     case FPGA_AN385:
+    case FPGA_AN386:
+    case FPGA_AN500:
     {
         /* The overflow IRQs for UARTs 0, 1 and 2 are ORed together.
          * Overflow for UARTs 4 and 5 doesn't trigger any interrupt.
@@ -377,9 +398,9 @@ static void mps2_common_init(MachineState *machine)
     /* In hardware this is a LAN9220; the LAN9118 is software compatible
      * except that it doesn't support the checksum-offload feature.
      */
-    lan9118_init(&nd_table[0], 0x40200000,
+    lan9118_init(&nd_table[0], mmc->ethernet_base,
                  qdev_get_gpio_in(armv7m,
-                                  mmc->fpga_type == FPGA_AN385 ? 13 : 47));
+                                  mmc->fpga_type == FPGA_AN511 ? 47 : 13));
 
     system_clock_scale = NANOSECONDS_PER_SECOND / SYSCLK_FRQ;
 
@@ -406,6 +427,37 @@ static void mps2_an385_class_init(ObjectClass *oc, void *data)
     mmc->fpga_type = FPGA_AN385;
     mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-m3");
     mmc->scc_id = 0x41043850;
+    mmc->psram_base = 0x21000000;
+    mmc->ethernet_base = 0x40200000;
+    mmc->has_block_ram = true;
+}
+
+static void mps2_an386_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    MPS2MachineClass *mmc = MPS2_MACHINE_CLASS(oc);
+
+    mc->desc = "ARM MPS2 with AN386 FPGA image for Cortex-M4";
+    mmc->fpga_type = FPGA_AN386;
+    mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-m4");
+    mmc->scc_id = 0x41043860;
+    mmc->psram_base = 0x21000000;
+    mmc->ethernet_base = 0x40200000;
+    mmc->has_block_ram = true;
+}
+
+static void mps2_an500_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    MPS2MachineClass *mmc = MPS2_MACHINE_CLASS(oc);
+
+    mc->desc = "ARM MPS2 with AN500 FPGA image for Cortex-M7";
+    mmc->fpga_type = FPGA_AN500;
+    mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-m7");
+    mmc->scc_id = 0x41045000;
+    mmc->psram_base = 0x60000000;
+    mmc->ethernet_base = 0xa0000000;
+    mmc->has_block_ram = false;
 }
 
 static void mps2_an511_class_init(ObjectClass *oc, void *data)
@@ -417,6 +469,9 @@ static void mps2_an511_class_init(ObjectClass *oc, void *data)
     mmc->fpga_type = FPGA_AN511;
     mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-m3");
     mmc->scc_id = 0x41045110;
+    mmc->psram_base = 0x21000000;
+    mmc->ethernet_base = 0x40200000;
+    mmc->has_block_ram = false;
 }
 
 static const TypeInfo mps2_info = {
@@ -434,6 +489,18 @@ static const TypeInfo mps2_an385_info = {
     .class_init = mps2_an385_class_init,
 };
 
+static const TypeInfo mps2_an386_info = {
+    .name = TYPE_MPS2_AN386_MACHINE,
+    .parent = TYPE_MPS2_MACHINE,
+    .class_init = mps2_an386_class_init,
+};
+
+static const TypeInfo mps2_an500_info = {
+    .name = TYPE_MPS2_AN500_MACHINE,
+    .parent = TYPE_MPS2_MACHINE,
+    .class_init = mps2_an500_class_init,
+};
+
 static const TypeInfo mps2_an511_info = {
     .name = TYPE_MPS2_AN511_MACHINE,
     .parent = TYPE_MPS2_MACHINE,
@@ -444,6 +511,8 @@ static void mps2_machine_init(void)
 {
     type_register_static(&mps2_info);
     type_register_static(&mps2_an385_info);
+    type_register_static(&mps2_an386_info);
+    type_register_static(&mps2_an500_info);
     type_register_static(&mps2_an511_info);
 }
 
diff --git a/hw/arm/npcm7xx.c b/hw/arm/npcm7xx.c
new file mode 100644
index 0000000000..037f3a26f2
--- /dev/null
+++ b/hw/arm/npcm7xx.c
@@ -0,0 +1,532 @@
+/*
+ * Nuvoton NPCM7xx SoC family.
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "exec/address-spaces.h"
+#include "hw/arm/boot.h"
+#include "hw/arm/npcm7xx.h"
+#include "hw/char/serial.h"
+#include "hw/loader.h"
+#include "hw/misc/unimp.h"
+#include "hw/qdev-properties.h"
+#include "qapi/error.h"
+#include "qemu/units.h"
+#include "sysemu/sysemu.h"
+
+/*
+ * This covers the whole MMIO space. We'll use this to catch any MMIO accesses
+ * that aren't handled by any device.
+ */
+#define NPCM7XX_MMIO_BA         (0x80000000)
+#define NPCM7XX_MMIO_SZ         (0x7ffd0000)
+
+/* OTP key storage and fuse strap array */
+#define NPCM7XX_OTP1_BA         (0xf0189000)
+#define NPCM7XX_OTP2_BA         (0xf018a000)
+
+/* Core system modules. */
+#define NPCM7XX_L2C_BA          (0xf03fc000)
+#define NPCM7XX_CPUP_BA         (0xf03fe000)
+#define NPCM7XX_GCR_BA          (0xf0800000)
+#define NPCM7XX_CLK_BA          (0xf0801000)
+#define NPCM7XX_MC_BA           (0xf0824000)
+
+/* Internal AHB SRAM */
+#define NPCM7XX_RAM3_BA         (0xc0008000)
+#define NPCM7XX_RAM3_SZ         (4 * KiB)
+
+/* Memory blocks at the end of the address space */
+#define NPCM7XX_RAM2_BA         (0xfffd0000)
+#define NPCM7XX_RAM2_SZ         (128 * KiB)
+#define NPCM7XX_ROM_BA          (0xffff0000)
+#define NPCM7XX_ROM_SZ          (64 * KiB)
+
+/* Clock configuration values to be fixed up when bypassing bootloader */
+
+/* Run PLL1 at 1600 MHz */
+#define NPCM7XX_PLLCON1_FIXUP_VAL   (0x00402101)
+/* Run the CPU from PLL1 and UART from PLL2 */
+#define NPCM7XX_CLKSEL_FIXUP_VAL    (0x004aaba9)
+
+/*
+ * Interrupt lines going into the GIC. This does not include internal Cortex-A9
+ * interrupts.
+ */
+enum NPCM7xxInterrupt {
+    NPCM7XX_UART0_IRQ           = 2,
+    NPCM7XX_UART1_IRQ,
+    NPCM7XX_UART2_IRQ,
+    NPCM7XX_UART3_IRQ,
+    NPCM7XX_TIMER0_IRQ          = 32,   /* Timer Module 0 */
+    NPCM7XX_TIMER1_IRQ,
+    NPCM7XX_TIMER2_IRQ,
+    NPCM7XX_TIMER3_IRQ,
+    NPCM7XX_TIMER4_IRQ,
+    NPCM7XX_TIMER5_IRQ,                 /* Timer Module 1 */
+    NPCM7XX_TIMER6_IRQ,
+    NPCM7XX_TIMER7_IRQ,
+    NPCM7XX_TIMER8_IRQ,
+    NPCM7XX_TIMER9_IRQ,
+    NPCM7XX_TIMER10_IRQ,                /* Timer Module 2 */
+    NPCM7XX_TIMER11_IRQ,
+    NPCM7XX_TIMER12_IRQ,
+    NPCM7XX_TIMER13_IRQ,
+    NPCM7XX_TIMER14_IRQ,
+};
+
+/* Total number of GIC interrupts, including internal Cortex-A9 interrupts. */
+#define NPCM7XX_NUM_IRQ         (160)
+
+/* Register base address for each Timer Module */
+static const hwaddr npcm7xx_tim_addr[] = {
+    0xf0008000,
+    0xf0009000,
+    0xf000a000,
+};
+
+/* Register base address for each 16550 UART */
+static const hwaddr npcm7xx_uart_addr[] = {
+    0xf0001000,
+    0xf0002000,
+    0xf0003000,
+    0xf0004000,
+};
+
+/* Direct memory-mapped access to SPI0 CS0-1. */
+static const hwaddr npcm7xx_fiu0_flash_addr[] = {
+    0x80000000, /* CS0 */
+    0x88000000, /* CS1 */
+};
+
+/* Direct memory-mapped access to SPI3 CS0-3. */
+static const hwaddr npcm7xx_fiu3_flash_addr[] = {
+    0xa0000000, /* CS0 */
+    0xa8000000, /* CS1 */
+    0xb0000000, /* CS2 */
+    0xb8000000, /* CS3 */
+};
+
+static const struct {
+    const char *name;
+    hwaddr regs_addr;
+    int cs_count;
+    const hwaddr *flash_addr;
+} npcm7xx_fiu[] = {
+    {
+        .name = "fiu0",
+        .regs_addr = 0xfb000000,
+        .cs_count = ARRAY_SIZE(npcm7xx_fiu0_flash_addr),
+        .flash_addr = npcm7xx_fiu0_flash_addr,
+    }, {
+        .name = "fiu3",
+        .regs_addr = 0xc0000000,
+        .cs_count = ARRAY_SIZE(npcm7xx_fiu3_flash_addr),
+        .flash_addr = npcm7xx_fiu3_flash_addr,
+    },
+};
+
+static void npcm7xx_write_board_setup(ARMCPU *cpu,
+                                      const struct arm_boot_info *info)
+{
+    uint32_t board_setup[] = {
+        0xe59f0010,     /* ldr r0, clk_base_addr */
+        0xe59f1010,     /* ldr r1, pllcon1_value */
+        0xe5801010,     /* str r1, [r0, #16] */
+        0xe59f100c,     /* ldr r1, clksel_value */
+        0xe5801004,     /* str r1, [r0, #4] */
+        0xe12fff1e,     /* bx lr */
+        NPCM7XX_CLK_BA,
+        NPCM7XX_PLLCON1_FIXUP_VAL,
+        NPCM7XX_CLKSEL_FIXUP_VAL,
+    };
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(board_setup); i++) {
+        board_setup[i] = tswap32(board_setup[i]);
+    }
+    rom_add_blob_fixed("board-setup", board_setup, sizeof(board_setup),
+                       info->board_setup_addr);
+}
+
+static void npcm7xx_write_secondary_boot(ARMCPU *cpu,
+                                         const struct arm_boot_info *info)
+{
+    /*
+     * The default smpboot stub halts the secondary CPU with a 'wfi'
+     * instruction, but the arch/arm/mach-npcm/platsmp.c in the Linux kernel
+     * does not send an IPI to wake it up, so the second CPU fails to boot. So
+     * we need to provide our own smpboot stub that can not use 'wfi', it has
+     * to spin the secondary CPU until the first CPU writes to the SCRPAD reg.
+     */
+    uint32_t smpboot[] = {
+        0xe59f2018,     /* ldr r2, bootreg_addr */
+        0xe3a00000,     /* mov r0, #0 */
+        0xe5820000,     /* str r0, [r2] */
+        0xe320f002,     /* wfe */
+        0xe5921000,     /* ldr r1, [r2] */
+        0xe1110001,     /* tst r1, r1 */
+        0x0afffffb,     /* beq <wfe> */
+        0xe12fff11,     /* bx r1 */
+        NPCM7XX_SMP_BOOTREG_ADDR,
+    };
+    int i;
+
+    for (i = 0; i < ARRAY_SIZE(smpboot); i++) {
+        smpboot[i] = tswap32(smpboot[i]);
+    }
+
+    rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),
+                       NPCM7XX_SMP_LOADER_START);
+}
+
+static struct arm_boot_info npcm7xx_binfo = {
+    .loader_start           = NPCM7XX_LOADER_START,
+    .smp_loader_start       = NPCM7XX_SMP_LOADER_START,
+    .smp_bootreg_addr       = NPCM7XX_SMP_BOOTREG_ADDR,
+    .gic_cpu_if_addr        = NPCM7XX_GIC_CPU_IF_ADDR,
+    .write_secondary_boot   = npcm7xx_write_secondary_boot,
+    .board_id               = -1,
+    .board_setup_addr       = NPCM7XX_BOARD_SETUP_ADDR,
+    .write_board_setup      = npcm7xx_write_board_setup,
+};
+
+void npcm7xx_load_kernel(MachineState *machine, NPCM7xxState *soc)
+{
+    NPCM7xxClass *sc = NPCM7XX_GET_CLASS(soc);
+
+    npcm7xx_binfo.ram_size = machine->ram_size;
+    npcm7xx_binfo.nb_cpus = sc->num_cpus;
+
+    arm_load_kernel(&soc->cpu[0], machine, &npcm7xx_binfo);
+}
+
+static void npcm7xx_init_fuses(NPCM7xxState *s)
+{
+    NPCM7xxClass *nc = NPCM7XX_GET_CLASS(s);
+    uint32_t value;
+
+    /*
+     * The initial mask of disabled modules indicates the chip derivative (e.g.
+     * NPCM750 or NPCM730).
+     */
+    value = tswap32(nc->disabled_modules);
+    npcm7xx_otp_array_write(&s->fuse_array, &value, NPCM7XX_FUSE_DERIVATIVE,
+                            sizeof(value));
+}
+
+static qemu_irq npcm7xx_irq(NPCM7xxState *s, int n)
+{
+    return qdev_get_gpio_in(DEVICE(&s->a9mpcore), n);
+}
+
+static void npcm7xx_init(Object *obj)
+{
+    NPCM7xxState *s = NPCM7XX(obj);
+    int i;
+
+    for (i = 0; i < NPCM7XX_MAX_NUM_CPUS; i++) {
+        object_initialize_child(obj, "cpu[*]", &s->cpu[i],
+                                ARM_CPU_TYPE_NAME("cortex-a9"));
+    }
+
+    object_initialize_child(obj, "a9mpcore", &s->a9mpcore, TYPE_A9MPCORE_PRIV);
+    object_initialize_child(obj, "gcr", &s->gcr, TYPE_NPCM7XX_GCR);
+    object_property_add_alias(obj, "power-on-straps", OBJECT(&s->gcr),
+                              "power-on-straps");
+    object_initialize_child(obj, "clk", &s->clk, TYPE_NPCM7XX_CLK);
+    object_initialize_child(obj, "otp1", &s->key_storage,
+                            TYPE_NPCM7XX_KEY_STORAGE);
+    object_initialize_child(obj, "otp2", &s->fuse_array,
+                            TYPE_NPCM7XX_FUSE_ARRAY);
+    object_initialize_child(obj, "mc", &s->mc, TYPE_NPCM7XX_MC);
+
+    for (i = 0; i < ARRAY_SIZE(s->tim); i++) {
+        object_initialize_child(obj, "tim[*]", &s->tim[i], TYPE_NPCM7XX_TIMER);
+    }
+
+    QEMU_BUILD_BUG_ON(ARRAY_SIZE(npcm7xx_fiu) != ARRAY_SIZE(s->fiu));
+    for (i = 0; i < ARRAY_SIZE(s->fiu); i++) {
+        object_initialize_child(obj, npcm7xx_fiu[i].name, &s->fiu[i],
+                                TYPE_NPCM7XX_FIU);
+    }
+}
+
+static void npcm7xx_realize(DeviceState *dev, Error **errp)
+{
+    NPCM7xxState *s = NPCM7XX(dev);
+    NPCM7xxClass *nc = NPCM7XX_GET_CLASS(s);
+    int i;
+
+    if (memory_region_size(s->dram) > NPCM7XX_DRAM_SZ) {
+        error_setg(errp, "%s: NPCM7xx cannot address more than %" PRIu64
+                   " MiB of DRAM", __func__, NPCM7XX_DRAM_SZ / MiB);
+        return;
+    }
+
+    /* CPUs */
+    for (i = 0; i < nc->num_cpus; i++) {
+        object_property_set_int(OBJECT(&s->cpu[i]), "mp-affinity",
+                                arm_cpu_mp_affinity(i, NPCM7XX_MAX_NUM_CPUS),
+                                &error_abort);
+        object_property_set_int(OBJECT(&s->cpu[i]), "reset-cbar",
+                                NPCM7XX_GIC_CPU_IF_ADDR, &error_abort);
+        object_property_set_bool(OBJECT(&s->cpu[i]), "reset-hivecs", true,
+                                 &error_abort);
+
+        /* Disable security extensions. */
+        object_property_set_bool(OBJECT(&s->cpu[i]), "has_el3", false,
+                                 &error_abort);
+
+        if (!qdev_realize(DEVICE(&s->cpu[i]), NULL, errp)) {
+            return;
+        }
+    }
+
+    /* A9MPCORE peripherals. Can only fail if we pass bad parameters here. */
+    object_property_set_int(OBJECT(&s->a9mpcore), "num-cpu", nc->num_cpus,
+                            &error_abort);
+    object_property_set_int(OBJECT(&s->a9mpcore), "num-irq", NPCM7XX_NUM_IRQ,
+                            &error_abort);
+    sysbus_realize(SYS_BUS_DEVICE(&s->a9mpcore), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->a9mpcore), 0, NPCM7XX_CPUP_BA);
+
+    for (i = 0; i < nc->num_cpus; i++) {
+        sysbus_connect_irq(SYS_BUS_DEVICE(&s->a9mpcore), i,
+                           qdev_get_gpio_in(DEVICE(&s->cpu[i]), ARM_CPU_IRQ));
+        sysbus_connect_irq(SYS_BUS_DEVICE(&s->a9mpcore), i + nc->num_cpus,
+                           qdev_get_gpio_in(DEVICE(&s->cpu[i]), ARM_CPU_FIQ));
+    }
+
+    /* L2 cache controller */
+    sysbus_create_simple("l2x0", NPCM7XX_L2C_BA, NULL);
+
+    /* System Global Control Registers (GCR). Can fail due to user input. */
+    object_property_set_int(OBJECT(&s->gcr), "disabled-modules",
+                            nc->disabled_modules, &error_abort);
+    object_property_add_const_link(OBJECT(&s->gcr), "dram-mr", OBJECT(s->dram));
+    if (!sysbus_realize(SYS_BUS_DEVICE(&s->gcr), errp)) {
+        return;
+    }
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->gcr), 0, NPCM7XX_GCR_BA);
+
+    /* Clock Control Registers (CLK). Cannot fail. */
+    sysbus_realize(SYS_BUS_DEVICE(&s->clk), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->clk), 0, NPCM7XX_CLK_BA);
+
+    /* OTP key storage and fuse strap array. Cannot fail. */
+    sysbus_realize(SYS_BUS_DEVICE(&s->key_storage), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->key_storage), 0, NPCM7XX_OTP1_BA);
+    sysbus_realize(SYS_BUS_DEVICE(&s->fuse_array), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->fuse_array), 0, NPCM7XX_OTP2_BA);
+    npcm7xx_init_fuses(s);
+
+    /* Fake Memory Controller (MC). Cannot fail. */
+    sysbus_realize(SYS_BUS_DEVICE(&s->mc), &error_abort);
+    sysbus_mmio_map(SYS_BUS_DEVICE(&s->mc), 0, NPCM7XX_MC_BA);
+
+    /* Timer Modules (TIM). Cannot fail. */
+    QEMU_BUILD_BUG_ON(ARRAY_SIZE(npcm7xx_tim_addr) != ARRAY_SIZE(s->tim));
+    for (i = 0; i < ARRAY_SIZE(s->tim); i++) {
+        SysBusDevice *sbd = SYS_BUS_DEVICE(&s->tim[i]);
+        int first_irq;
+        int j;
+
+        sysbus_realize(sbd, &error_abort);
+        sysbus_mmio_map(sbd, 0, npcm7xx_tim_addr[i]);
+
+        first_irq = NPCM7XX_TIMER0_IRQ + i * NPCM7XX_TIMERS_PER_CTRL;
+        for (j = 0; j < NPCM7XX_TIMERS_PER_CTRL; j++) {
+            qemu_irq irq = npcm7xx_irq(s, first_irq + j);
+            sysbus_connect_irq(sbd, j, irq);
+        }
+    }
+
+    /* UART0..3 (16550 compatible) */
+    for (i = 0; i < ARRAY_SIZE(npcm7xx_uart_addr); i++) {
+        serial_mm_init(get_system_memory(), npcm7xx_uart_addr[i], 2,
+                       npcm7xx_irq(s, NPCM7XX_UART0_IRQ + i), 115200,
+                       serial_hd(i), DEVICE_LITTLE_ENDIAN);
+    }
+
+    /*
+     * Flash Interface Unit (FIU). Can fail if incorrect number of chip selects
+     * specified, but this is a programming error.
+     */
+    QEMU_BUILD_BUG_ON(ARRAY_SIZE(npcm7xx_fiu) != ARRAY_SIZE(s->fiu));
+    for (i = 0; i < ARRAY_SIZE(s->fiu); i++) {
+        SysBusDevice *sbd = SYS_BUS_DEVICE(&s->fiu[i]);
+        int j;
+
+        object_property_set_int(OBJECT(sbd), "cs-count",
+                                npcm7xx_fiu[i].cs_count, &error_abort);
+        sysbus_realize(sbd, &error_abort);
+
+        sysbus_mmio_map(sbd, 0, npcm7xx_fiu[i].regs_addr);
+        for (j = 0; j < npcm7xx_fiu[i].cs_count; j++) {
+            sysbus_mmio_map(sbd, j + 1, npcm7xx_fiu[i].flash_addr[j]);
+        }
+    }
+
+    /* RAM2 (SRAM) */
+    memory_region_init_ram(&s->sram, OBJECT(dev), "ram2",
+                           NPCM7XX_RAM2_SZ, &error_abort);
+    memory_region_add_subregion(get_system_memory(), NPCM7XX_RAM2_BA, &s->sram);
+
+    /* RAM3 (SRAM) */
+    memory_region_init_ram(&s->ram3, OBJECT(dev), "ram3",
+                           NPCM7XX_RAM3_SZ, &error_abort);
+    memory_region_add_subregion(get_system_memory(), NPCM7XX_RAM3_BA, &s->ram3);
+
+    /* Internal ROM */
+    memory_region_init_rom(&s->irom, OBJECT(dev), "irom", NPCM7XX_ROM_SZ,
+                           &error_abort);
+    memory_region_add_subregion(get_system_memory(), NPCM7XX_ROM_BA, &s->irom);
+
+    create_unimplemented_device("npcm7xx.shm",          0xc0001000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.vdmx",         0xe0800000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.pcierc",       0xe1000000,  64 * KiB);
+    create_unimplemented_device("npcm7xx.kcs",          0xf0007000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.rng",          0xf000b000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.adc",          0xf000c000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gfxi",         0xf000e000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[0]",      0xf0010000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[1]",      0xf0011000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[2]",      0xf0012000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[3]",      0xf0013000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[4]",      0xf0014000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[5]",      0xf0015000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[6]",      0xf0016000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.gpio[7]",      0xf0017000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[0]",     0xf0080000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[1]",     0xf0081000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[2]",     0xf0082000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[3]",     0xf0083000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[4]",     0xf0084000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[5]",     0xf0085000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[6]",     0xf0086000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[7]",     0xf0087000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[8]",     0xf0088000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[9]",     0xf0089000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[10]",    0xf008a000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[11]",    0xf008b000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[12]",    0xf008c000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[13]",    0xf008d000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[14]",    0xf008e000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.smbus[15]",    0xf008f000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.espi",         0xf009f000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.peci",         0xf0100000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.siox[1]",      0xf0101000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.siox[2]",      0xf0102000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.pwm[0]",       0xf0103000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.pwm[1]",       0xf0104000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[0]",       0xf0180000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[1]",       0xf0181000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[2]",       0xf0182000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[3]",       0xf0183000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[4]",       0xf0184000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[5]",       0xf0185000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[6]",       0xf0186000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.mft[7]",       0xf0187000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.pspi1",        0xf0200000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.pspi2",        0xf0201000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.ahbpci",       0xf0400000,   1 * MiB);
+    create_unimplemented_device("npcm7xx.mcphy",        0xf05f0000,  64 * KiB);
+    create_unimplemented_device("npcm7xx.gmac1",        0xf0802000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.gmac2",        0xf0804000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.ehci",         0xf0806000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.ohci",         0xf0807000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.vcd",          0xf0810000,  64 * KiB);
+    create_unimplemented_device("npcm7xx.ece",          0xf0820000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.vdma",         0xf0822000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.emc1",         0xf0825000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.emc2",         0xf0826000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[0]",      0xf0830000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[1]",      0xf0831000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[2]",      0xf0832000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[3]",      0xf0833000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[4]",      0xf0834000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[5]",      0xf0835000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[6]",      0xf0836000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[7]",      0xf0837000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[8]",      0xf0838000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.usbd[9]",      0xf0839000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.sd",           0xf0840000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.mmc",          0xf0842000,   8 * KiB);
+    create_unimplemented_device("npcm7xx.pcimbx",       0xf0848000, 512 * KiB);
+    create_unimplemented_device("npcm7xx.aes",          0xf0858000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.des",          0xf0859000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.sha",          0xf085a000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.secacc",       0xf085b000,   4 * KiB);
+    create_unimplemented_device("npcm7xx.spixcs0",      0xf8000000,  16 * MiB);
+    create_unimplemented_device("npcm7xx.spixcs1",      0xf9000000,  16 * MiB);
+    create_unimplemented_device("npcm7xx.spix",         0xfb001000,   4 * KiB);
+}
+
+static Property npcm7xx_properties[] = {
+    DEFINE_PROP_LINK("dram-mr", NPCM7xxState, dram, TYPE_MEMORY_REGION,
+                     MemoryRegion *),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void npcm7xx_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+
+    dc->realize = npcm7xx_realize;
+    dc->user_creatable = false;
+    device_class_set_props(dc, npcm7xx_properties);
+}
+
+static void npcm730_class_init(ObjectClass *oc, void *data)
+{
+    NPCM7xxClass *nc = NPCM7XX_CLASS(oc);
+
+    /* NPCM730 is optimized for data center use, so no graphics, etc. */
+    nc->disabled_modules = 0x00300395;
+    nc->num_cpus = 2;
+}
+
+static void npcm750_class_init(ObjectClass *oc, void *data)
+{
+    NPCM7xxClass *nc = NPCM7XX_CLASS(oc);
+
+    /* NPCM750 has 2 cores and a full set of peripherals */
+    nc->disabled_modules = 0x00000000;
+    nc->num_cpus = 2;
+}
+
+static const TypeInfo npcm7xx_soc_types[] = {
+    {
+        .name           = TYPE_NPCM7XX,
+        .parent         = TYPE_DEVICE,
+        .instance_size  = sizeof(NPCM7xxState),
+        .instance_init  = npcm7xx_init,
+        .class_size     = sizeof(NPCM7xxClass),
+        .class_init     = npcm7xx_class_init,
+        .abstract       = true,
+    }, {
+        .name           = TYPE_NPCM730,
+        .parent         = TYPE_NPCM7XX,
+        .class_init     = npcm730_class_init,
+    }, {
+        .name           = TYPE_NPCM750,
+        .parent         = TYPE_NPCM7XX,
+        .class_init     = npcm750_class_init,
+    },
+};
+
+DEFINE_TYPES(npcm7xx_soc_types);
diff --git a/hw/arm/npcm7xx_boards.c b/hw/arm/npcm7xx_boards.c
new file mode 100644
index 0000000000..79e2e2744c
--- /dev/null
+++ b/hw/arm/npcm7xx_boards.c
@@ -0,0 +1,197 @@
+/*
+ * Machine definitions for boards featuring an NPCM7xx SoC.
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "exec/address-spaces.h"
+#include "hw/arm/npcm7xx.h"
+#include "hw/core/cpu.h"
+#include "hw/loader.h"
+#include "hw/qdev-properties.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "qemu/units.h"
+#include "sysemu/sysemu.h"
+
+#define NPCM750_EVB_POWER_ON_STRAPS 0x00001ff7
+#define QUANTA_GSJ_POWER_ON_STRAPS 0x00001fff
+
+static const char npcm7xx_default_bootrom[] = "npcm7xx_bootrom.bin";
+
+static void npcm7xx_load_bootrom(MachineState *machine, NPCM7xxState *soc)
+{
+    g_autofree char *filename = NULL;
+    int ret;
+
+    if (!bios_name) {
+        bios_name = npcm7xx_default_bootrom;
+    }
+
+    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
+    if (!filename) {
+        error_report("Could not find ROM image '%s'", bios_name);
+        if (!machine->kernel_filename) {
+            /* We can't boot without a bootrom or a kernel image. */
+            exit(1);
+        }
+        return;
+    }
+    ret = load_image_mr(filename, &soc->irom);
+    if (ret < 0) {
+        error_report("Failed to load ROM image '%s'", filename);
+        exit(1);
+    }
+}
+
+static void npcm7xx_connect_flash(NPCM7xxFIUState *fiu, int cs_no,
+                                  const char *flash_type, DriveInfo *dinfo)
+{
+    DeviceState *flash;
+    qemu_irq flash_cs;
+
+    flash = qdev_new(flash_type);
+    if (dinfo) {
+        qdev_prop_set_drive(flash, "drive", blk_by_legacy_dinfo(dinfo));
+    }
+    qdev_realize_and_unref(flash, BUS(fiu->spi), &error_fatal);
+
+    flash_cs = qdev_get_gpio_in_named(flash, SSI_GPIO_CS, 0);
+    qdev_connect_gpio_out_named(DEVICE(fiu), "cs", cs_no, flash_cs);
+}
+
+static void npcm7xx_connect_dram(NPCM7xxState *soc, MemoryRegion *dram)
+{
+    memory_region_add_subregion(get_system_memory(), NPCM7XX_DRAM_BA, dram);
+
+    object_property_set_link(OBJECT(soc), "dram-mr", OBJECT(dram),
+                             &error_abort);
+}
+
+static NPCM7xxState *npcm7xx_create_soc(MachineState *machine,
+                                        uint32_t hw_straps)
+{
+    NPCM7xxMachineClass *nmc = NPCM7XX_MACHINE_GET_CLASS(machine);
+    MachineClass *mc = &nmc->parent;
+    Object *obj;
+
+    if (strcmp(machine->cpu_type, mc->default_cpu_type) != 0) {
+        error_report("This board can only be used with %s",
+                     mc->default_cpu_type);
+        exit(1);
+    }
+
+    obj = object_new_with_props(nmc->soc_type, OBJECT(machine), "soc",
+                                &error_abort, NULL);
+    object_property_set_uint(obj, "power-on-straps", hw_straps, &error_abort);
+
+    return NPCM7XX(obj);
+}
+
+static void npcm750_evb_init(MachineState *machine)
+{
+    NPCM7xxState *soc;
+
+    soc = npcm7xx_create_soc(machine, NPCM750_EVB_POWER_ON_STRAPS);
+    npcm7xx_connect_dram(soc, machine->ram);
+    qdev_realize(DEVICE(soc), NULL, &error_fatal);
+
+    npcm7xx_load_bootrom(machine, soc);
+    npcm7xx_connect_flash(&soc->fiu[0], 0, "w25q256", drive_get(IF_MTD, 0, 0));
+    npcm7xx_load_kernel(machine, soc);
+}
+
+static void quanta_gsj_init(MachineState *machine)
+{
+    NPCM7xxState *soc;
+
+    soc = npcm7xx_create_soc(machine, QUANTA_GSJ_POWER_ON_STRAPS);
+    npcm7xx_connect_dram(soc, machine->ram);
+    qdev_realize(DEVICE(soc), NULL, &error_fatal);
+
+    npcm7xx_load_bootrom(machine, soc);
+    npcm7xx_connect_flash(&soc->fiu[0], 0, "mx25l25635e",
+                          drive_get(IF_MTD, 0, 0));
+    npcm7xx_load_kernel(machine, soc);
+}
+
+static void npcm7xx_set_soc_type(NPCM7xxMachineClass *nmc, const char *type)
+{
+    NPCM7xxClass *sc = NPCM7XX_CLASS(object_class_by_name(type));
+    MachineClass *mc = MACHINE_CLASS(nmc);
+
+    nmc->soc_type = type;
+    mc->default_cpus = mc->min_cpus = mc->max_cpus = sc->num_cpus;
+}
+
+static void npcm7xx_machine_class_init(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    mc->no_floppy = 1;
+    mc->no_cdrom = 1;
+    mc->no_parallel = 1;
+    mc->default_ram_id = "ram";
+    mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-a9");
+}
+
+/*
+ * Schematics:
+ * https://github.com/Nuvoton-Israel/nuvoton-info/blob/master/npcm7xx-poleg/evaluation-board/board_deliverables/NPCM750x_EB_ver.A1.1_COMPLETE.pdf
+ */
+static void npcm750_evb_machine_class_init(ObjectClass *oc, void *data)
+{
+    NPCM7xxMachineClass *nmc = NPCM7XX_MACHINE_CLASS(oc);
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    npcm7xx_set_soc_type(nmc, TYPE_NPCM750);
+
+    mc->desc = "Nuvoton NPCM750 Evaluation Board (Cortex A9)";
+    mc->init = npcm750_evb_init;
+    mc->default_ram_size = 512 * MiB;
+};
+
+static void gsj_machine_class_init(ObjectClass *oc, void *data)
+{
+    NPCM7xxMachineClass *nmc = NPCM7XX_MACHINE_CLASS(oc);
+    MachineClass *mc = MACHINE_CLASS(oc);
+
+    npcm7xx_set_soc_type(nmc, TYPE_NPCM730);
+
+    mc->desc = "Quanta GSJ (Cortex A9)";
+    mc->init = quanta_gsj_init;
+    mc->default_ram_size = 512 * MiB;
+};
+
+static const TypeInfo npcm7xx_machine_types[] = {
+    {
+        .name           = TYPE_NPCM7XX_MACHINE,
+        .parent         = TYPE_MACHINE,
+        .instance_size  = sizeof(NPCM7xxMachine),
+        .class_size     = sizeof(NPCM7xxMachineClass),
+        .class_init     = npcm7xx_machine_class_init,
+        .abstract       = true,
+    }, {
+        .name           = MACHINE_TYPE_NAME("npcm750-evb"),
+        .parent         = TYPE_NPCM7XX_MACHINE,
+        .class_init     = npcm750_evb_machine_class_init,
+    }, {
+        .name           = MACHINE_TYPE_NAME("quanta-gsj"),
+        .parent         = TYPE_NPCM7XX_MACHINE,
+        .class_init     = gsj_machine_class_init,
+    },
+};
+
+DEFINE_TYPES(npcm7xx_machine_types)
diff --git a/hw/arm/xlnx-versal-virt.c b/hw/arm/xlnx-versal-virt.c
index 5a01e856fd..1f9409eb32 100644
--- a/hw/arm/xlnx-versal-virt.c
+++ b/hw/arm/xlnx-versal-virt.c
@@ -214,7 +214,7 @@ static void fdt_add_gem_nodes(VersalVirt *s)
                               s->phandle.ethernet_phy[i]);
         qemu_fdt_setprop_cells(s->fdt, name, "clocks",
                                s->phandle.clk_25Mhz, s->phandle.clk_25Mhz,
-                               s->phandle.clk_25Mhz, s->phandle.clk_25Mhz);
+                               s->phandle.clk_125Mhz, s->phandle.clk_125Mhz);
         qemu_fdt_setprop(s->fdt, name, "clock-names",
                          clocknames, sizeof(clocknames));
         qemu_fdt_setprop_cells(s->fdt, name, "interrupts",
diff --git a/hw/mem/meson.build b/hw/mem/meson.build
index ba424622bb..0d22f2b572 100644
--- a/hw/mem/meson.build
+++ b/hw/mem/meson.build
@@ -1,6 +1,7 @@
 mem_ss = ss.source_set()
 mem_ss.add(files('memory-device.c'))
 mem_ss.add(when: 'CONFIG_DIMM', if_true: files('pc-dimm.c'))
+mem_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_mc.c'))
 mem_ss.add(when: 'CONFIG_NVDIMM', if_true: files('nvdimm.c'))
 
 softmmu_ss.add_all(when: 'CONFIG_MEM_DEVICE', if_true: mem_ss)
diff --git a/hw/mem/npcm7xx_mc.c b/hw/mem/npcm7xx_mc.c
new file mode 100644
index 0000000000..0435d06ab4
--- /dev/null
+++ b/hw/mem/npcm7xx_mc.c
@@ -0,0 +1,84 @@
+/*
+ * Nuvoton NPCM7xx Memory Controller stub
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/mem/npcm7xx_mc.h"
+#include "qapi/error.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+
+#define NPCM7XX_MC_REGS_SIZE (4 * KiB)
+
+static uint64_t npcm7xx_mc_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    /*
+     * If bits 8..11 @ offset 0 are not zero, the boot block thinks the memory
+     * controller has already been initialized and will skip DDR training.
+     */
+    if (addr == 0) {
+        return 0x100;
+    }
+
+    qemu_log_mask(LOG_UNIMP, "%s: mostly unimplemented\n", __func__);
+
+    return 0;
+}
+
+static void npcm7xx_mc_write(void *opaque, hwaddr addr, uint64_t v,
+                             unsigned int size)
+{
+    qemu_log_mask(LOG_UNIMP, "%s: mostly unimplemented\n", __func__);
+}
+
+static const MemoryRegionOps npcm7xx_mc_ops = {
+    .read = npcm7xx_mc_read,
+    .write = npcm7xx_mc_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+        .unaligned = false,
+    },
+};
+
+static void npcm7xx_mc_realize(DeviceState *dev, Error **errp)
+{
+    NPCM7xxMCState *s = NPCM7XX_MC(dev);
+
+    memory_region_init_io(&s->mmio, OBJECT(s), &npcm7xx_mc_ops, s, "regs",
+                          NPCM7XX_MC_REGS_SIZE);
+    sysbus_init_mmio(&s->parent, &s->mmio);
+}
+
+static void npcm7xx_mc_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "NPCM7xx Memory Controller stub";
+    dc->realize = npcm7xx_mc_realize;
+}
+
+static const TypeInfo npcm7xx_mc_types[] = {
+    {
+        .name = TYPE_NPCM7XX_MC,
+        .parent = TYPE_SYS_BUS_DEVICE,
+        .instance_size = sizeof(NPCM7xxMCState),
+        .class_init = npcm7xx_mc_class_init,
+    },
+};
+DEFINE_TYPES(npcm7xx_mc_types);
diff --git a/hw/misc/a9scu.c b/hw/misc/a9scu.c
index 324371a1c0..a375ebc987 100644
--- a/hw/misc/a9scu.c
+++ b/hw/misc/a9scu.c
@@ -12,8 +12,12 @@
 #include "hw/misc/a9scu.h"
 #include "hw/qdev-properties.h"
 #include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qemu/log.h"
 #include "qemu/module.h"
 
+#define A9_SCU_CPU_MAX  4
+
 static uint64_t a9_scu_read(void *opaque, hwaddr offset,
                             unsigned size)
 {
@@ -25,12 +29,6 @@ static uint64_t a9_scu_read(void *opaque, hwaddr offset,
         return (((1 << s->num_cpu) - 1) << 4) | (s->num_cpu - 1);
     case 0x08: /* CPU Power Status */
         return s->status;
-    case 0x09: /* CPU status.  */
-        return s->status >> 8;
-    case 0x0a: /* CPU status.  */
-        return s->status >> 16;
-    case 0x0b: /* CPU status.  */
-        return s->status >> 24;
     case 0x0c: /* Invalidate All Registers In Secure State */
         return 0;
     case 0x40: /* Filtering Start Address Register */
@@ -41,6 +39,8 @@ static uint64_t a9_scu_read(void *opaque, hwaddr offset,
     case 0x54: /* SCU Non-secure Access Control Register */
         /* unimplemented, fall through */
     default:
+        qemu_log_mask(LOG_UNIMP, "%s: Unsupported offset 0x%"HWADDR_PRIx"\n",
+                      __func__, offset);
         return 0;
     }
 }
@@ -49,23 +49,6 @@ static void a9_scu_write(void *opaque, hwaddr offset,
                          uint64_t value, unsigned size)
 {
     A9SCUState *s = (A9SCUState *)opaque;
-    uint32_t mask;
-    uint32_t shift;
-    switch (size) {
-    case 1:
-        mask = 0xff;
-        break;
-    case 2:
-        mask = 0xffff;
-        break;
-    case 4:
-        mask = 0xffffffff;
-        break;
-    default:
-        fprintf(stderr, "Invalid size %u in write to a9 scu register %x\n",
-                size, (unsigned)offset);
-        return;
-    }
 
     switch (offset) {
     case 0x00: /* Control */
@@ -74,9 +57,7 @@ static void a9_scu_write(void *opaque, hwaddr offset,
     case 0x4: /* Configuration: RO */
         break;
     case 0x08: case 0x09: case 0x0A: case 0x0B: /* Power Control */
-        shift = (offset - 0x8) * 8;
-        s->status &= ~(mask << shift);
-        s->status |= ((value & mask) << shift);
+        s->status = value;
         break;
     case 0x0c: /* Invalidate All Registers In Secure State */
         /* no-op as we do not implement caches */
@@ -89,6 +70,9 @@ static void a9_scu_write(void *opaque, hwaddr offset,
     case 0x54: /* SCU Non-secure Access Control Register */
         /* unimplemented, fall through */
     default:
+        qemu_log_mask(LOG_UNIMP, "%s: Unsupported offset 0x%"HWADDR_PRIx
+                                 " value 0x%"PRIx64"\n",
+                      __func__, offset, value);
         break;
     }
 }
@@ -96,6 +80,14 @@ static void a9_scu_write(void *opaque, hwaddr offset,
 static const MemoryRegionOps a9_scu_ops = {
     .read = a9_scu_read,
     .write = a9_scu_write,
+    .impl = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+    },
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
     .endianness = DEVICE_NATIVE_ENDIAN,
 };
 
@@ -105,12 +97,17 @@ static void a9_scu_reset(DeviceState *dev)
     s->control = 0;
 }
 
-static void a9_scu_init(Object *obj)
+static void a9_scu_realize(DeviceState *dev, Error **errp)
 {
-    A9SCUState *s = A9_SCU(obj);
-    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+    A9SCUState *s = A9_SCU(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+
+    if (!s->num_cpu || s->num_cpu > A9_SCU_CPU_MAX) {
+        error_setg(errp, "Illegal CPU count: %u", s->num_cpu);
+        return;
+    }
 
-    memory_region_init_io(&s->iomem, obj, &a9_scu_ops, s,
+    memory_region_init_io(&s->iomem, OBJECT(s), &a9_scu_ops, s,
                           "a9-scu", 0x100);
     sysbus_init_mmio(sbd, &s->iomem);
 }
@@ -138,13 +135,13 @@ static void a9_scu_class_init(ObjectClass *klass, void *data)
     device_class_set_props(dc, a9_scu_properties);
     dc->vmsd = &vmstate_a9_scu;
     dc->reset = a9_scu_reset;
+    dc->realize = a9_scu_realize;
 }
 
 static const TypeInfo a9_scu_info = {
     .name          = TYPE_A9_SCU,
     .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(A9SCUState),
-    .instance_init = a9_scu_init,
     .class_init    = a9_scu_class_init,
 };
 
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index bd24132757..793d45b1dc 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -56,6 +56,10 @@ softmmu_ss.add(when: 'CONFIG_IMX', if_true: files(
 ))
 softmmu_ss.add(when: 'CONFIG_MILKYMIST', if_true: files('milkymist-hpdmc.c', 'milkymist-pfpu.c'))
 softmmu_ss.add(when: 'CONFIG_MAINSTONE', if_true: files('mst_fpga.c'))
+softmmu_ss.add(when: 'CONFIG_NPCM7XX', if_true: files(
+  'npcm7xx_clk.c',
+  'npcm7xx_gcr.c',
+))
 softmmu_ss.add(when: 'CONFIG_OMAP', if_true: files(
   'omap_clk.c',
   'omap_gpmc.c',
diff --git a/hw/misc/npcm7xx_clk.c b/hw/misc/npcm7xx_clk.c
new file mode 100644
index 0000000000..21ab4200d1
--- /dev/null
+++ b/hw/misc/npcm7xx_clk.c
@@ -0,0 +1,266 @@
+/*
+ * Nuvoton NPCM7xx Clock Control Registers.
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/misc/npcm7xx_clk.h"
+#include "migration/vmstate.h"
+#include "qemu/error-report.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/timer.h"
+#include "qemu/units.h"
+#include "trace.h"
+
+#define PLLCON_LOKI     BIT(31)
+#define PLLCON_LOKS     BIT(30)
+#define PLLCON_PWDEN    BIT(12)
+
+enum NPCM7xxCLKRegisters {
+    NPCM7XX_CLK_CLKEN1,
+    NPCM7XX_CLK_CLKSEL,
+    NPCM7XX_CLK_CLKDIV1,
+    NPCM7XX_CLK_PLLCON0,
+    NPCM7XX_CLK_PLLCON1,
+    NPCM7XX_CLK_SWRSTR,
+    NPCM7XX_CLK_IPSRST1         = 0x20 / sizeof(uint32_t),
+    NPCM7XX_CLK_IPSRST2,
+    NPCM7XX_CLK_CLKEN2,
+    NPCM7XX_CLK_CLKDIV2,
+    NPCM7XX_CLK_CLKEN3,
+    NPCM7XX_CLK_IPSRST3,
+    NPCM7XX_CLK_WD0RCR,
+    NPCM7XX_CLK_WD1RCR,
+    NPCM7XX_CLK_WD2RCR,
+    NPCM7XX_CLK_SWRSTC1,
+    NPCM7XX_CLK_SWRSTC2,
+    NPCM7XX_CLK_SWRSTC3,
+    NPCM7XX_CLK_SWRSTC4,
+    NPCM7XX_CLK_PLLCON2,
+    NPCM7XX_CLK_CLKDIV3,
+    NPCM7XX_CLK_CORSTC,
+    NPCM7XX_CLK_PLLCONG,
+    NPCM7XX_CLK_AHBCKFI,
+    NPCM7XX_CLK_SECCNT,
+    NPCM7XX_CLK_CNTR25M,
+    NPCM7XX_CLK_REGS_END,
+};
+
+/*
+ * These reset values were taken from version 0.91 of the NPCM750R data sheet.
+ *
+ * All are loaded on power-up reset. CLKENx and SWRSTR should also be loaded on
+ * core domain reset, but this reset type is not yet supported by QEMU.
+ */
+static const uint32_t cold_reset_values[NPCM7XX_CLK_NR_REGS] = {
+    [NPCM7XX_CLK_CLKEN1]        = 0xffffffff,
+    [NPCM7XX_CLK_CLKSEL]        = 0x004aaaaa,
+    [NPCM7XX_CLK_CLKDIV1]       = 0x5413f855,
+    [NPCM7XX_CLK_PLLCON0]       = 0x00222101 | PLLCON_LOKI,
+    [NPCM7XX_CLK_PLLCON1]       = 0x00202101 | PLLCON_LOKI,
+    [NPCM7XX_CLK_IPSRST1]       = 0x00001000,
+    [NPCM7XX_CLK_IPSRST2]       = 0x80000000,
+    [NPCM7XX_CLK_CLKEN2]        = 0xffffffff,
+    [NPCM7XX_CLK_CLKDIV2]       = 0xaa4f8f9f,
+    [NPCM7XX_CLK_CLKEN3]        = 0xffffffff,
+    [NPCM7XX_CLK_IPSRST3]       = 0x03000000,
+    [NPCM7XX_CLK_WD0RCR]        = 0xffffffff,
+    [NPCM7XX_CLK_WD1RCR]        = 0xffffffff,
+    [NPCM7XX_CLK_WD2RCR]        = 0xffffffff,
+    [NPCM7XX_CLK_SWRSTC1]       = 0x00000003,
+    [NPCM7XX_CLK_PLLCON2]       = 0x00c02105 | PLLCON_LOKI,
+    [NPCM7XX_CLK_CORSTC]        = 0x04000003,
+    [NPCM7XX_CLK_PLLCONG]       = 0x01228606 | PLLCON_LOKI,
+    [NPCM7XX_CLK_AHBCKFI]       = 0x000000c8,
+};
+
+static uint64_t npcm7xx_clk_read(void *opaque, hwaddr offset, unsigned size)
+{
+    uint32_t reg = offset / sizeof(uint32_t);
+    NPCM7xxCLKState *s = opaque;
+    int64_t now_ns;
+    uint32_t value = 0;
+
+    if (reg >= NPCM7XX_CLK_NR_REGS) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: offset 0x%04" HWADDR_PRIx " out of range\n",
+                      __func__, offset);
+        return 0;
+    }
+
+    switch (reg) {
+    case NPCM7XX_CLK_SWRSTR:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: register @ 0x%04" HWADDR_PRIx " is write-only\n",
+                      __func__, offset);
+        break;
+
+    case NPCM7XX_CLK_SECCNT:
+        now_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+        value = (now_ns - s->ref_ns) / NANOSECONDS_PER_SECOND;
+        break;
+
+    case NPCM7XX_CLK_CNTR25M:
+        now_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+        /*
+         * This register counts 25 MHz cycles, updating every 640 ns. It rolls
+         * over to zero every second.
+         *
+         * The 4 LSBs are always zero: (1e9 / 640) << 4 = 25000000.
+         */
+        value = (((now_ns - s->ref_ns) / 640) << 4) % NPCM7XX_TIMER_REF_HZ;
+        break;
+
+    default:
+        value = s->regs[reg];
+        break;
+    };
+
+    trace_npcm7xx_clk_read(offset, value);
+
+    return value;
+}
+
+static void npcm7xx_clk_write(void *opaque, hwaddr offset,
+                              uint64_t v, unsigned size)
+{
+    uint32_t reg = offset / sizeof(uint32_t);
+    NPCM7xxCLKState *s = opaque;
+    uint32_t value = v;
+
+    trace_npcm7xx_clk_write(offset, value);
+
+    if (reg >= NPCM7XX_CLK_NR_REGS) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: offset 0x%04" HWADDR_PRIx " out of range\n",
+                      __func__, offset);
+        return;
+    }
+
+    switch (reg) {
+    case NPCM7XX_CLK_SWRSTR:
+        qemu_log_mask(LOG_UNIMP, "%s: SW reset not implemented: 0x%02x\n",
+                      __func__, value);
+        value = 0;
+        break;
+
+    case NPCM7XX_CLK_PLLCON0:
+    case NPCM7XX_CLK_PLLCON1:
+    case NPCM7XX_CLK_PLLCON2:
+    case NPCM7XX_CLK_PLLCONG:
+        if (value & PLLCON_PWDEN) {
+            /* Power down -- clear lock and indicate loss of lock */
+            value &= ~PLLCON_LOKI;
+            value |= PLLCON_LOKS;
+        } else {
+            /* Normal mode -- assume always locked */
+            value |= PLLCON_LOKI;
+            /* Keep LOKS unchanged unless cleared by writing 1 */
+            if (value & PLLCON_LOKS) {
+                value &= ~PLLCON_LOKS;
+            } else {
+                value |= (value & PLLCON_LOKS);
+            }
+        }
+        break;
+
+    case NPCM7XX_CLK_CNTR25M:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: register @ 0x%04" HWADDR_PRIx " is read-only\n",
+                      __func__, offset);
+        return;
+    }
+
+    s->regs[reg] = value;
+}
+
+static const struct MemoryRegionOps npcm7xx_clk_ops = {
+    .read       = npcm7xx_clk_read,
+    .write      = npcm7xx_clk_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid      = {
+        .min_access_size        = 4,
+        .max_access_size        = 4,
+        .unaligned              = false,
+    },
+};
+
+static void npcm7xx_clk_enter_reset(Object *obj, ResetType type)
+{
+    NPCM7xxCLKState *s = NPCM7XX_CLK(obj);
+
+    QEMU_BUILD_BUG_ON(sizeof(s->regs) != sizeof(cold_reset_values));
+
+    switch (type) {
+    case RESET_TYPE_COLD:
+        memcpy(s->regs, cold_reset_values, sizeof(cold_reset_values));
+        s->ref_ns = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+        return;
+    }
+
+    /*
+     * A small number of registers need to be reset on a core domain reset,
+     * but no such reset type exists yet.
+     */
+    qemu_log_mask(LOG_UNIMP, "%s: reset type %d not implemented.",
+                  __func__, type);
+}
+
+static void npcm7xx_clk_init(Object *obj)
+{
+    NPCM7xxCLKState *s = NPCM7XX_CLK(obj);
+
+    memory_region_init_io(&s->iomem, obj, &npcm7xx_clk_ops, s,
+                          TYPE_NPCM7XX_CLK, 4 * KiB);
+    sysbus_init_mmio(&s->parent, &s->iomem);
+}
+
+static const VMStateDescription vmstate_npcm7xx_clk = {
+    .name = "npcm7xx-clk",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, NPCM7xxCLKState, NPCM7XX_CLK_NR_REGS),
+        VMSTATE_INT64(ref_ns, NPCM7xxCLKState),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static void npcm7xx_clk_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    QEMU_BUILD_BUG_ON(NPCM7XX_CLK_REGS_END > NPCM7XX_CLK_NR_REGS);
+
+    dc->desc = "NPCM7xx Clock Control Registers";
+    dc->vmsd = &vmstate_npcm7xx_clk;
+    rc->phases.enter = npcm7xx_clk_enter_reset;
+}
+
+static const TypeInfo npcm7xx_clk_info = {
+    .name               = TYPE_NPCM7XX_CLK,
+    .parent             = TYPE_SYS_BUS_DEVICE,
+    .instance_size      = sizeof(NPCM7xxCLKState),
+    .instance_init      = npcm7xx_clk_init,
+    .class_init         = npcm7xx_clk_class_init,
+};
+
+static void npcm7xx_clk_register_type(void)
+{
+    type_register_static(&npcm7xx_clk_info);
+}
+type_init(npcm7xx_clk_register_type);
diff --git a/hw/misc/npcm7xx_gcr.c b/hw/misc/npcm7xx_gcr.c
new file mode 100644
index 0000000000..745f690809
--- /dev/null
+++ b/hw/misc/npcm7xx_gcr.c
@@ -0,0 +1,269 @@
+/*
+ * Nuvoton NPCM7xx System Global Control Registers.
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/misc/npcm7xx_gcr.h"
+#include "hw/qdev-properties.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qemu/cutils.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+
+#include "trace.h"
+
+#define NPCM7XX_GCR_MIN_DRAM_SIZE   (128 * MiB)
+#define NPCM7XX_GCR_MAX_DRAM_SIZE   (2 * GiB)
+
+enum NPCM7xxGCRRegisters {
+    NPCM7XX_GCR_PDID,
+    NPCM7XX_GCR_PWRON,
+    NPCM7XX_GCR_MFSEL1          = 0x0c / sizeof(uint32_t),
+    NPCM7XX_GCR_MFSEL2,
+    NPCM7XX_GCR_MISCPE,
+    NPCM7XX_GCR_SPSWC           = 0x038 / sizeof(uint32_t),
+    NPCM7XX_GCR_INTCR,
+    NPCM7XX_GCR_INTSR,
+    NPCM7XX_GCR_HIFCR           = 0x050 / sizeof(uint32_t),
+    NPCM7XX_GCR_INTCR2          = 0x060 / sizeof(uint32_t),
+    NPCM7XX_GCR_MFSEL3,
+    NPCM7XX_GCR_SRCNT,
+    NPCM7XX_GCR_RESSR,
+    NPCM7XX_GCR_RLOCKR1,
+    NPCM7XX_GCR_FLOCKR1,
+    NPCM7XX_GCR_DSCNT,
+    NPCM7XX_GCR_MDLR,
+    NPCM7XX_GCR_SCRPAD3,
+    NPCM7XX_GCR_SCRPAD2,
+    NPCM7XX_GCR_DAVCLVLR        = 0x098 / sizeof(uint32_t),
+    NPCM7XX_GCR_INTCR3,
+    NPCM7XX_GCR_VSINTR          = 0x0ac / sizeof(uint32_t),
+    NPCM7XX_GCR_MFSEL4,
+    NPCM7XX_GCR_CPBPNTR         = 0x0c4 / sizeof(uint32_t),
+    NPCM7XX_GCR_CPCTL           = 0x0d0 / sizeof(uint32_t),
+    NPCM7XX_GCR_CP2BST,
+    NPCM7XX_GCR_B2CPNT,
+    NPCM7XX_GCR_CPPCTL,
+    NPCM7XX_GCR_I2CSEGSEL,
+    NPCM7XX_GCR_I2CSEGCTL,
+    NPCM7XX_GCR_VSRCR,
+    NPCM7XX_GCR_MLOCKR,
+    NPCM7XX_GCR_SCRPAD          = 0x013c / sizeof(uint32_t),
+    NPCM7XX_GCR_USB1PHYCTL,
+    NPCM7XX_GCR_USB2PHYCTL,
+    NPCM7XX_GCR_REGS_END,
+};
+
+static const uint32_t cold_reset_values[NPCM7XX_GCR_NR_REGS] = {
+    [NPCM7XX_GCR_PDID]          = 0x04a92750,   /* Poleg A1 */
+    [NPCM7XX_GCR_MISCPE]        = 0x0000ffff,
+    [NPCM7XX_GCR_SPSWC]         = 0x00000003,
+    [NPCM7XX_GCR_INTCR]         = 0x0000035e,
+    [NPCM7XX_GCR_HIFCR]         = 0x0000004e,
+    [NPCM7XX_GCR_INTCR2]        = (1U << 19),   /* DDR initialized */
+    [NPCM7XX_GCR_RESSR]         = 0x80000000,
+    [NPCM7XX_GCR_DSCNT]         = 0x000000c0,
+    [NPCM7XX_GCR_DAVCLVLR]      = 0x5a00f3cf,
+    [NPCM7XX_GCR_SCRPAD]        = 0x00000008,
+    [NPCM7XX_GCR_USB1PHYCTL]    = 0x034730e4,
+    [NPCM7XX_GCR_USB2PHYCTL]    = 0x034730e4,
+};
+
+static uint64_t npcm7xx_gcr_read(void *opaque, hwaddr offset, unsigned size)
+{
+    uint32_t reg = offset / sizeof(uint32_t);
+    NPCM7xxGCRState *s = opaque;
+
+    if (reg >= NPCM7XX_GCR_NR_REGS) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: offset 0x%04" HWADDR_PRIx " out of range\n",
+                      __func__, offset);
+        return 0;
+    }
+
+    trace_npcm7xx_gcr_read(offset, s->regs[reg]);
+
+    return s->regs[reg];
+}
+
+static void npcm7xx_gcr_write(void *opaque, hwaddr offset,
+                              uint64_t v, unsigned size)
+{
+    uint32_t reg = offset / sizeof(uint32_t);
+    NPCM7xxGCRState *s = opaque;
+    uint32_t value = v;
+
+    trace_npcm7xx_gcr_write(offset, value);
+
+    if (reg >= NPCM7XX_GCR_NR_REGS) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: offset 0x%04" HWADDR_PRIx " out of range\n",
+                      __func__, offset);
+        return;
+    }
+
+    switch (reg) {
+    case NPCM7XX_GCR_PDID:
+    case NPCM7XX_GCR_PWRON:
+    case NPCM7XX_GCR_INTSR:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: register @ 0x%04" HWADDR_PRIx " is read-only\n",
+                      __func__, offset);
+        return;
+
+    case NPCM7XX_GCR_RESSR:
+    case NPCM7XX_GCR_CP2BST:
+        /* Write 1 to clear */
+        value = s->regs[reg] & ~value;
+        break;
+
+    case NPCM7XX_GCR_RLOCKR1:
+    case NPCM7XX_GCR_MDLR:
+        /* Write 1 to set */
+        value |= s->regs[reg];
+        break;
+    };
+
+    s->regs[reg] = value;
+}
+
+static const struct MemoryRegionOps npcm7xx_gcr_ops = {
+    .read       = npcm7xx_gcr_read,
+    .write      = npcm7xx_gcr_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid      = {
+        .min_access_size        = 4,
+        .max_access_size        = 4,
+        .unaligned              = false,
+    },
+};
+
+static void npcm7xx_gcr_enter_reset(Object *obj, ResetType type)
+{
+    NPCM7xxGCRState *s = NPCM7XX_GCR(obj);
+
+    QEMU_BUILD_BUG_ON(sizeof(s->regs) != sizeof(cold_reset_values));
+
+    switch (type) {
+    case RESET_TYPE_COLD:
+        memcpy(s->regs, cold_reset_values, sizeof(s->regs));
+        s->regs[NPCM7XX_GCR_PWRON] = s->reset_pwron;
+        s->regs[NPCM7XX_GCR_MDLR] = s->reset_mdlr;
+        s->regs[NPCM7XX_GCR_INTCR3] = s->reset_intcr3;
+        break;
+    }
+}
+
+static void npcm7xx_gcr_realize(DeviceState *dev, Error **errp)
+{
+    ERRP_GUARD();
+    NPCM7xxGCRState *s = NPCM7XX_GCR(dev);
+    uint64_t dram_size;
+    Object *obj;
+
+    obj = object_property_get_link(OBJECT(dev), "dram-mr", errp);
+    if (!obj) {
+        error_prepend(errp, "%s: required dram-mr link not found: ", __func__);
+        return;
+    }
+    dram_size = memory_region_size(MEMORY_REGION(obj));
+    if (!is_power_of_2(dram_size) ||
+        dram_size < NPCM7XX_GCR_MIN_DRAM_SIZE ||
+        dram_size > NPCM7XX_GCR_MAX_DRAM_SIZE) {
+        g_autofree char *sz = size_to_str(dram_size);
+        g_autofree char *min_sz = size_to_str(NPCM7XX_GCR_MIN_DRAM_SIZE);
+        g_autofree char *max_sz = size_to_str(NPCM7XX_GCR_MAX_DRAM_SIZE);
+        error_setg(errp, "%s: unsupported DRAM size %s", __func__, sz);
+        error_append_hint(errp,
+                          "DRAM size must be a power of two between %s and %s,"
+                          " inclusive.\n", min_sz, max_sz);
+        return;
+    }
+
+    /* Power-on reset value */
+    s->reset_intcr3 = 0x00001002;
+
+    /*
+     * The GMMAP (Graphics Memory Map) field is used by u-boot to detect the
+     * DRAM size, and is normally initialized by the boot block as part of DRAM
+     * training. However, since we don't have a complete emulation of the
+     * memory controller and try to make it look like it has already been
+     * initialized, the boot block will skip this initialization, and we need
+     * to make sure this field is set correctly up front.
+     *
+     * WARNING: some versions of u-boot only looks at bits 8 and 9, so 2 GiB of
+     * DRAM will be interpreted as 128 MiB.
+     *
+     * https://github.com/Nuvoton-Israel/u-boot/blob/2aef993bd2aafeb5408dbaad0f3ce099ee40c4aa/board/nuvoton/poleg/poleg.c#L244
+     */
+    s->reset_intcr3 |= ctz64(dram_size / NPCM7XX_GCR_MIN_DRAM_SIZE) << 8;
+}
+
+static void npcm7xx_gcr_init(Object *obj)
+{
+    NPCM7xxGCRState *s = NPCM7XX_GCR(obj);
+
+    memory_region_init_io(&s->iomem, obj, &npcm7xx_gcr_ops, s,
+                          TYPE_NPCM7XX_GCR, 4 * KiB);
+    sysbus_init_mmio(&s->parent, &s->iomem);
+}
+
+static const VMStateDescription vmstate_npcm7xx_gcr = {
+    .name = "npcm7xx-gcr",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, NPCM7xxGCRState, NPCM7XX_GCR_NR_REGS),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static Property npcm7xx_gcr_properties[] = {
+    DEFINE_PROP_UINT32("disabled-modules", NPCM7xxGCRState, reset_mdlr, 0),
+    DEFINE_PROP_UINT32("power-on-straps", NPCM7xxGCRState, reset_pwron, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void npcm7xx_gcr_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    QEMU_BUILD_BUG_ON(NPCM7XX_GCR_REGS_END > NPCM7XX_GCR_NR_REGS);
+
+    dc->desc = "NPCM7xx System Global Control Registers";
+    dc->realize = npcm7xx_gcr_realize;
+    dc->vmsd = &vmstate_npcm7xx_gcr;
+    rc->phases.enter = npcm7xx_gcr_enter_reset;
+
+    device_class_set_props(dc, npcm7xx_gcr_properties);
+}
+
+static const TypeInfo npcm7xx_gcr_info = {
+    .name               = TYPE_NPCM7XX_GCR,
+    .parent             = TYPE_SYS_BUS_DEVICE,
+    .instance_size      = sizeof(NPCM7xxGCRState),
+    .instance_init      = npcm7xx_gcr_init,
+    .class_init         = npcm7xx_gcr_class_init,
+};
+
+static void npcm7xx_gcr_register_type(void)
+{
+    type_register_static(&npcm7xx_gcr_info);
+}
+type_init(npcm7xx_gcr_register_type);
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 56a622d1e9..6054f9adf3 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -110,6 +110,14 @@ mos6522_set_sr_int(void) "set sr_int"
 mos6522_write(uint64_t addr, uint64_t val) "reg=0x%"PRIx64 " val=0x%"PRIx64
 mos6522_read(uint64_t addr, unsigned val) "reg=0x%"PRIx64 " val=0x%x"
 
+# npcm7xx_clk.c
+npcm7xx_clk_read(uint64_t offset, uint32_t value) " offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+npcm7xx_clk_write(uint64_t offset, uint32_t value) "offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+
+# npcm7xx_gcr.c
+npcm7xx_gcr_read(uint64_t offset, uint32_t value) " offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+npcm7xx_gcr_write(uint64_t offset, uint32_t value) "offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+
 # stm32f4xx_syscfg.c
 stm32f4xx_syscfg_set_irq(int gpio, int line, int level) "Interupt: GPIO: %d, Line: %d; Level: %d"
 stm32f4xx_pulse_exti(int irq) "Pulse EXTI: %d"
diff --git a/hw/nvram/meson.build b/hw/nvram/meson.build
index ba214558ac..1f2ed013b2 100644
--- a/hw/nvram/meson.build
+++ b/hw/nvram/meson.build
@@ -4,6 +4,7 @@ softmmu_ss.add(when: 'CONFIG_DS1225Y', if_true: files('ds1225y.c'))
 softmmu_ss.add(when: 'CONFIG_NMC93XX_EEPROM', if_true: files('eeprom93xx.c'))
 softmmu_ss.add(when: 'CONFIG_AT24C', if_true: files('eeprom_at24c.c'))
 softmmu_ss.add(when: 'CONFIG_MAC_NVRAM', if_true: files('mac_nvram.c'))
+softmmu_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_otp.c'))
 softmmu_ss.add(when: 'CONFIG_NRF51_SOC', if_true: files('nrf51_nvm.c'))
 
 specific_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr_nvram.c'))
diff --git a/hw/nvram/npcm7xx_otp.c b/hw/nvram/npcm7xx_otp.c
new file mode 100644
index 0000000000..b16ca530ba
--- /dev/null
+++ b/hw/nvram/npcm7xx_otp.c
@@ -0,0 +1,440 @@
+/*
+ * Nuvoton NPCM7xx OTP (Fuse Array) Interface
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/nvram/npcm7xx_otp.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qemu/bitops.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+
+/* Each module has 4 KiB of register space. Only a fraction of it is used. */
+#define NPCM7XX_OTP_REGS_SIZE (4 * KiB)
+
+/* 32-bit register indices. */
+typedef enum NPCM7xxOTPRegister {
+    NPCM7XX_OTP_FST,
+    NPCM7XX_OTP_FADDR,
+    NPCM7XX_OTP_FDATA,
+    NPCM7XX_OTP_FCFG,
+    /* Offset 0x10 is FKEYIND in OTP1, FUSTRAP in OTP2 */
+    NPCM7XX_OTP_FKEYIND = 0x0010 / sizeof(uint32_t),
+    NPCM7XX_OTP_FUSTRAP = 0x0010 / sizeof(uint32_t),
+    NPCM7XX_OTP_FCTL,
+    NPCM7XX_OTP_REGS_END,
+} NPCM7xxOTPRegister;
+
+/* Register field definitions. */
+#define FST_RIEN BIT(2)
+#define FST_RDST BIT(1)
+#define FST_RDY BIT(0)
+#define FST_RO_MASK (FST_RDST | FST_RDY)
+
+#define FADDR_BYTEADDR(rv) extract32((rv), 0, 10)
+#define FADDR_BITPOS(rv) extract32((rv), 10, 3)
+
+#define FDATA_CLEAR 0x00000001
+
+#define FCFG_FDIS BIT(31)
+#define FCFG_FCFGLK_MASK 0x00ff0000
+
+#define FCTL_PROG_CMD1 0x00000001
+#define FCTL_PROG_CMD2 0xbf79e5d0
+#define FCTL_READ_CMD 0x00000002
+
+/**
+ * struct NPCM7xxOTPClass - OTP module class.
+ * @parent: System bus device class.
+ * @mmio_ops: MMIO register operations for this type of module.
+ *
+ * The two OTP modules (key-storage and fuse-array) have slightly different
+ * behavior, so we give them different MMIO register operations.
+ */
+struct NPCM7xxOTPClass {
+    SysBusDeviceClass parent;
+
+    const MemoryRegionOps *mmio_ops;
+};
+
+#define NPCM7XX_OTP_CLASS(klass) \
+    OBJECT_CLASS_CHECK(NPCM7xxOTPClass, (klass), TYPE_NPCM7XX_OTP)
+#define NPCM7XX_OTP_GET_CLASS(obj) \
+    OBJECT_GET_CLASS(NPCM7xxOTPClass, (obj), TYPE_NPCM7XX_OTP)
+
+static uint8_t ecc_encode_nibble(uint8_t n)
+{
+    uint8_t result = n;
+
+    result |= (((n >> 0) & 1) ^ ((n >> 1) & 1)) << 4;
+    result |= (((n >> 2) & 1) ^ ((n >> 3) & 1)) << 5;
+    result |= (((n >> 0) & 1) ^ ((n >> 2) & 1)) << 6;
+    result |= (((n >> 1) & 1) ^ ((n >> 3) & 1)) << 7;
+
+    return result;
+}
+
+void npcm7xx_otp_array_write(NPCM7xxOTPState *s, const void *data,
+                             unsigned int offset, unsigned int len)
+{
+    const uint8_t *src = data;
+    uint8_t *dst = &s->array[offset];
+
+    while (len-- > 0) {
+        uint8_t c = *src++;
+
+        *dst++ = ecc_encode_nibble(extract8(c, 0, 4));
+        *dst++ = ecc_encode_nibble(extract8(c, 4, 4));
+    }
+}
+
+/* Common register read handler for both OTP classes. */
+static uint64_t npcm7xx_otp_read(NPCM7xxOTPState *s, NPCM7xxOTPRegister reg)
+{
+    uint32_t value = 0;
+
+    switch (reg) {
+    case NPCM7XX_OTP_FST:
+    case NPCM7XX_OTP_FADDR:
+    case NPCM7XX_OTP_FDATA:
+    case NPCM7XX_OTP_FCFG:
+        value = s->regs[reg];
+        break;
+
+    case NPCM7XX_OTP_FCTL:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: read from write-only FCTL register\n",
+                      DEVICE(s)->canonical_path);
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: read from invalid offset 0x%zx\n",
+                      DEVICE(s)->canonical_path, reg * sizeof(uint32_t));
+        break;
+    }
+
+    return value;
+}
+
+/* Read a byte from the OTP array into the data register. */
+static void npcm7xx_otp_read_array(NPCM7xxOTPState *s)
+{
+    uint32_t faddr = s->regs[NPCM7XX_OTP_FADDR];
+
+    s->regs[NPCM7XX_OTP_FDATA] = s->array[FADDR_BYTEADDR(faddr)];
+    s->regs[NPCM7XX_OTP_FST] |= FST_RDST | FST_RDY;
+}
+
+/* Program a byte from the data register into the OTP array. */
+static void npcm7xx_otp_program_array(NPCM7xxOTPState *s)
+{
+    uint32_t faddr = s->regs[NPCM7XX_OTP_FADDR];
+
+    /* Bits can only go 0->1, never 1->0. */
+    s->array[FADDR_BYTEADDR(faddr)] |= (1U << FADDR_BITPOS(faddr));
+    s->regs[NPCM7XX_OTP_FST] |= FST_RDST | FST_RDY;
+}
+
+/* Compute the next value of the FCFG register. */
+static uint32_t npcm7xx_otp_compute_fcfg(uint32_t cur_value, uint32_t new_value)
+{
+    uint32_t lock_mask;
+    uint32_t value;
+
+    /*
+     * FCFGLK holds sticky bits 16..23, indicating which bits in FPRGLK (8..15)
+     * and FRDLK (0..7) that are read-only.
+     */
+    lock_mask = (cur_value & FCFG_FCFGLK_MASK) >> 8;
+    lock_mask |= lock_mask >> 8;
+    /* FDIS and FCFGLK bits are sticky (write 1 to set; can't clear). */
+    value = cur_value & (FCFG_FDIS | FCFG_FCFGLK_MASK);
+    /* Preserve read-only bits in FPRGLK and FRDLK */
+    value |= cur_value & lock_mask;
+    /* Set all bits that aren't read-only. */
+    value |= new_value & ~lock_mask;
+
+    return value;
+}
+
+/* Common register write handler for both OTP classes. */
+static void npcm7xx_otp_write(NPCM7xxOTPState *s, NPCM7xxOTPRegister reg,
+                              uint32_t value)
+{
+    switch (reg) {
+    case NPCM7XX_OTP_FST:
+        /* RDST is cleared by writing 1 to it. */
+        if (value & FST_RDST) {
+            s->regs[NPCM7XX_OTP_FST] &= ~FST_RDST;
+        }
+        /* Preserve read-only and write-one-to-clear bits */
+        value &= ~FST_RO_MASK;
+        value |= s->regs[NPCM7XX_OTP_FST] & FST_RO_MASK;
+        break;
+
+    case NPCM7XX_OTP_FADDR:
+        break;
+
+    case NPCM7XX_OTP_FDATA:
+        /*
+         * This register is cleared by writing a magic value to it; no other
+         * values can be written.
+         */
+        if (value == FDATA_CLEAR) {
+            value = 0;
+        } else {
+            value = s->regs[NPCM7XX_OTP_FDATA];
+        }
+        break;
+
+    case NPCM7XX_OTP_FCFG:
+        value = npcm7xx_otp_compute_fcfg(s->regs[NPCM7XX_OTP_FCFG], value);
+        break;
+
+    case NPCM7XX_OTP_FCTL:
+        switch (value) {
+        case FCTL_READ_CMD:
+            npcm7xx_otp_read_array(s);
+            break;
+
+        case FCTL_PROG_CMD1:
+            /*
+             * Programming requires writing two separate magic values to this
+             * register; this is the first one. Just store it so it can be
+             * verified later when the second magic value is received.
+             */
+            break;
+
+        case FCTL_PROG_CMD2:
+            /*
+             * Only initiate programming if we received the first half of the
+             * command immediately before this one.
+             */
+            if (s->regs[NPCM7XX_OTP_FCTL] == FCTL_PROG_CMD1) {
+                npcm7xx_otp_program_array(s);
+            }
+            break;
+
+        default:
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: unrecognized FCNTL value 0x%" PRIx32 "\n",
+                          DEVICE(s)->canonical_path, value);
+            break;
+        }
+        if (value != FCTL_PROG_CMD1) {
+            value = 0;
+        }
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: write to invalid offset 0x%zx\n",
+                      DEVICE(s)->canonical_path, reg * sizeof(uint32_t));
+        return;
+    }
+
+    s->regs[reg] = value;
+}
+
+/* Register read handler specific to the fuse array OTP module. */
+static uint64_t npcm7xx_fuse_array_read(void *opaque, hwaddr addr,
+                                        unsigned int size)
+{
+    NPCM7xxOTPRegister reg = addr / sizeof(uint32_t);
+    NPCM7xxOTPState *s = opaque;
+    uint32_t value;
+
+    /*
+     * Only the Fuse Strap register needs special handling; all other registers
+     * work the same way for both kinds of OTP modules.
+     */
+    if (reg != NPCM7XX_OTP_FUSTRAP) {
+        value = npcm7xx_otp_read(s, reg);
+    } else {
+        /* FUSTRAP is stored as three copies in the OTP array. */
+        uint32_t fustrap[3];
+
+        memcpy(fustrap, &s->array[0], sizeof(fustrap));
+
+        /* Determine value by a majority vote on each bit. */
+        value = (fustrap[0] & fustrap[1]) | (fustrap[0] & fustrap[2]) |
+                (fustrap[1] & fustrap[2]);
+    }
+
+    return value;
+}
+
+/* Register write handler specific to the fuse array OTP module. */
+static void npcm7xx_fuse_array_write(void *opaque, hwaddr addr, uint64_t v,
+                                     unsigned int size)
+{
+    NPCM7xxOTPRegister reg = addr / sizeof(uint32_t);
+    NPCM7xxOTPState *s = opaque;
+
+    /*
+     * The Fuse Strap register is read-only. Other registers are handled by
+     * common code.
+     */
+    if (reg != NPCM7XX_OTP_FUSTRAP) {
+        npcm7xx_otp_write(s, reg, v);
+    }
+}
+
+static const MemoryRegionOps npcm7xx_fuse_array_ops = {
+    .read       = npcm7xx_fuse_array_read,
+    .write      = npcm7xx_fuse_array_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid      = {
+        .min_access_size        = 4,
+        .max_access_size        = 4,
+        .unaligned              = false,
+    },
+};
+
+/* Register read handler specific to the key storage OTP module. */
+static uint64_t npcm7xx_key_storage_read(void *opaque, hwaddr addr,
+                                         unsigned int size)
+{
+    NPCM7xxOTPRegister reg = addr / sizeof(uint32_t);
+    NPCM7xxOTPState *s = opaque;
+
+    /*
+     * Only the Fuse Key Index register needs special handling; all other
+     * registers work the same way for both kinds of OTP modules.
+     */
+    if (reg != NPCM7XX_OTP_FKEYIND) {
+        return npcm7xx_otp_read(s, reg);
+    }
+
+    qemu_log_mask(LOG_UNIMP, "%s: FKEYIND is not implemented\n", __func__);
+
+    return s->regs[NPCM7XX_OTP_FKEYIND];
+}
+
+/* Register write handler specific to the key storage OTP module. */
+static void npcm7xx_key_storage_write(void *opaque, hwaddr addr, uint64_t v,
+                                      unsigned int size)
+{
+    NPCM7xxOTPRegister reg = addr / sizeof(uint32_t);
+    NPCM7xxOTPState *s = opaque;
+
+    /*
+     * Only the Fuse Key Index register needs special handling; all other
+     * registers work the same way for both kinds of OTP modules.
+     */
+    if (reg != NPCM7XX_OTP_FKEYIND) {
+        npcm7xx_otp_write(s, reg, v);
+        return;
+    }
+
+    qemu_log_mask(LOG_UNIMP, "%s: FKEYIND is not implemented\n", __func__);
+
+    s->regs[NPCM7XX_OTP_FKEYIND] = v;
+}
+
+static const MemoryRegionOps npcm7xx_key_storage_ops = {
+    .read       = npcm7xx_key_storage_read,
+    .write      = npcm7xx_key_storage_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid      = {
+        .min_access_size        = 4,
+        .max_access_size        = 4,
+        .unaligned              = false,
+    },
+};
+
+static void npcm7xx_otp_enter_reset(Object *obj, ResetType type)
+{
+    NPCM7xxOTPState *s = NPCM7XX_OTP(obj);
+
+    memset(s->regs, 0, sizeof(s->regs));
+
+    s->regs[NPCM7XX_OTP_FST] = 0x00000001;
+    s->regs[NPCM7XX_OTP_FCFG] = 0x20000000;
+}
+
+static void npcm7xx_otp_realize(DeviceState *dev, Error **errp)
+{
+    NPCM7xxOTPClass *oc = NPCM7XX_OTP_GET_CLASS(dev);
+    NPCM7xxOTPState *s = NPCM7XX_OTP(dev);
+    SysBusDevice *sbd = &s->parent;
+
+    memset(s->array, 0, sizeof(s->array));
+
+    memory_region_init_io(&s->mmio, OBJECT(s), oc->mmio_ops, s, "regs",
+                          NPCM7XX_OTP_REGS_SIZE);
+    sysbus_init_mmio(sbd, &s->mmio);
+}
+
+static const VMStateDescription vmstate_npcm7xx_otp = {
+    .name = "npcm7xx-otp",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(regs, NPCM7xxOTPState, NPCM7XX_OTP_NR_REGS),
+        VMSTATE_UINT8_ARRAY(array, NPCM7xxOTPState, NPCM7XX_OTP_ARRAY_BYTES),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static void npcm7xx_otp_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    QEMU_BUILD_BUG_ON(NPCM7XX_OTP_REGS_END > NPCM7XX_OTP_NR_REGS);
+
+    dc->realize = npcm7xx_otp_realize;
+    dc->vmsd = &vmstate_npcm7xx_otp;
+    rc->phases.enter = npcm7xx_otp_enter_reset;
+}
+
+static void npcm7xx_key_storage_class_init(ObjectClass *klass, void *data)
+{
+    NPCM7xxOTPClass *oc = NPCM7XX_OTP_CLASS(klass);
+
+    oc->mmio_ops = &npcm7xx_key_storage_ops;
+}
+
+static void npcm7xx_fuse_array_class_init(ObjectClass *klass, void *data)
+{
+    NPCM7xxOTPClass *oc = NPCM7XX_OTP_CLASS(klass);
+
+    oc->mmio_ops = &npcm7xx_fuse_array_ops;
+}
+
+static const TypeInfo npcm7xx_otp_types[] = {
+    {
+        .name = TYPE_NPCM7XX_OTP,
+        .parent = TYPE_SYS_BUS_DEVICE,
+        .instance_size = sizeof(NPCM7xxOTPState),
+        .class_size = sizeof(NPCM7xxOTPClass),
+        .class_init = npcm7xx_otp_class_init,
+        .abstract = true,
+    },
+    {
+        .name = TYPE_NPCM7XX_KEY_STORAGE,
+        .parent = TYPE_NPCM7XX_OTP,
+        .class_init = npcm7xx_key_storage_class_init,
+    },
+    {
+        .name = TYPE_NPCM7XX_FUSE_ARRAY,
+        .parent = TYPE_NPCM7XX_OTP,
+        .class_init = npcm7xx_fuse_array_class_init,
+    },
+};
+DEFINE_TYPES(npcm7xx_otp_types);
diff --git a/hw/ssi/meson.build b/hw/ssi/meson.build
index f1f5c287d0..dee00c0da6 100644
--- a/hw/ssi/meson.build
+++ b/hw/ssi/meson.build
@@ -1,5 +1,6 @@
 softmmu_ss.add(when: 'CONFIG_ASPEED_SOC', if_true: files('aspeed_smc.c'))
 softmmu_ss.add(when: 'CONFIG_MSF2', if_true: files('mss-spi.c'))
+softmmu_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_fiu.c'))
 softmmu_ss.add(when: 'CONFIG_PL022', if_true: files('pl022.c'))
 softmmu_ss.add(when: 'CONFIG_SSI', if_true: files('ssi.c'))
 softmmu_ss.add(when: 'CONFIG_STM32F2XX_SPI', if_true: files('stm32f2xx_spi.c'))
diff --git a/hw/ssi/npcm7xx_fiu.c b/hw/ssi/npcm7xx_fiu.c
new file mode 100644
index 0000000000..104e8f2b96
--- /dev/null
+++ b/hw/ssi/npcm7xx_fiu.c
@@ -0,0 +1,572 @@
+/*
+ * Nuvoton NPCM7xx Flash Interface Unit (FIU)
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/ssi/npcm7xx_fiu.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/units.h"
+
+#include "trace.h"
+
+/* Up to 128 MiB of flash may be accessed directly as memory. */
+#define NPCM7XX_FIU_FLASH_WINDOW_SIZE (128 * MiB)
+
+/* Each module has 4 KiB of register space. Only a fraction of it is used. */
+#define NPCM7XX_FIU_CTRL_REGS_SIZE (4 * KiB)
+
+/* 32-bit FIU register indices. */
+enum NPCM7xxFIURegister {
+    NPCM7XX_FIU_DRD_CFG,
+    NPCM7XX_FIU_DWR_CFG,
+    NPCM7XX_FIU_UMA_CFG,
+    NPCM7XX_FIU_UMA_CTS,
+    NPCM7XX_FIU_UMA_CMD,
+    NPCM7XX_FIU_UMA_ADDR,
+    NPCM7XX_FIU_PRT_CFG,
+    NPCM7XX_FIU_UMA_DW0 = 0x0020 / sizeof(uint32_t),
+    NPCM7XX_FIU_UMA_DW1,
+    NPCM7XX_FIU_UMA_DW2,
+    NPCM7XX_FIU_UMA_DW3,
+    NPCM7XX_FIU_UMA_DR0,
+    NPCM7XX_FIU_UMA_DR1,
+    NPCM7XX_FIU_UMA_DR2,
+    NPCM7XX_FIU_UMA_DR3,
+    NPCM7XX_FIU_PRT_CMD0,
+    NPCM7XX_FIU_PRT_CMD1,
+    NPCM7XX_FIU_PRT_CMD2,
+    NPCM7XX_FIU_PRT_CMD3,
+    NPCM7XX_FIU_PRT_CMD4,
+    NPCM7XX_FIU_PRT_CMD5,
+    NPCM7XX_FIU_PRT_CMD6,
+    NPCM7XX_FIU_PRT_CMD7,
+    NPCM7XX_FIU_PRT_CMD8,
+    NPCM7XX_FIU_PRT_CMD9,
+    NPCM7XX_FIU_CFG = 0x78 / sizeof(uint32_t),
+    NPCM7XX_FIU_REGS_END,
+};
+
+/* FIU_{DRD,DWR,UMA,PTR}_CFG cannot be written when this bit is set. */
+#define NPCM7XX_FIU_CFG_LCK BIT(31)
+
+/* Direct Read configuration register fields. */
+#define FIU_DRD_CFG_ADDSIZ(rv) extract32(rv, 16, 2)
+#define FIU_ADDSIZ_3BYTES 0
+#define FIU_ADDSIZ_4BYTES 1
+#define FIU_DRD_CFG_DBW(rv) extract32(rv, 12, 2)
+#define FIU_DRD_CFG_ACCTYPE(rv) extract32(rv, 8, 2)
+#define FIU_DRD_CFG_RDCMD(rv) extract32(rv, 0, 8)
+
+/* Direct Write configuration register fields. */
+#define FIU_DWR_CFG_ADDSIZ(rv) extract32(rv, 16, 2)
+#define FIU_DWR_CFG_WRCMD(rv) extract32(rv, 0, 8)
+
+/* User-Mode Access register fields. */
+
+/* Command Mode Lock and the bits protected by it. */
+#define FIU_UMA_CFG_CMMLCK BIT(30)
+#define FIU_UMA_CFG_CMMLCK_MASK 0x00000403
+
+#define FIU_UMA_CFG_RDATSIZ(rv) extract32(rv, 24, 5)
+#define FIU_UMA_CFG_DBSIZ(rv) extract32(rv, 21, 3)
+#define FIU_UMA_CFG_WDATSIZ(rv) extract32(rv, 16, 5)
+#define FIU_UMA_CFG_ADDSIZ(rv) extract32(rv, 11, 3)
+#define FIU_UMA_CFG_CMDSIZ(rv) extract32(rv, 10, 1)
+#define FIU_UMA_CFG_DBPCK(rv) extract32(rv, 6, 2)
+
+#define FIU_UMA_CTS_RDYIE BIT(25)
+#define FIU_UMA_CTS_RDYST BIT(24)
+#define FIU_UMA_CTS_SW_CS BIT(16)
+#define FIU_UMA_CTS_DEV_NUM(rv) extract32(rv, 8, 2)
+#define FIU_UMA_CTS_EXEC_DONE BIT(0)
+
+/*
+ * Returns the index of flash in the fiu->flash array. This corresponds to the
+ * chip select ID of the flash.
+ */
+static int npcm7xx_fiu_cs_index(NPCM7xxFIUState *fiu, NPCM7xxFIUFlash *flash)
+{
+    int index = flash - fiu->flash;
+
+    g_assert(index >= 0 && index < fiu->cs_count);
+
+    return index;
+}
+
+/* Assert the chip select specified in the UMA Control/Status Register. */
+static void npcm7xx_fiu_select(NPCM7xxFIUState *s, int cs_id)
+{
+    trace_npcm7xx_fiu_select(DEVICE(s)->canonical_path, cs_id);
+
+    if (cs_id < s->cs_count) {
+        qemu_irq_lower(s->cs_lines[cs_id]);
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: UMA to CS%d; this module has only %d chip selects",
+                      DEVICE(s)->canonical_path, cs_id, s->cs_count);
+        cs_id = -1;
+    }
+
+    s->active_cs = cs_id;
+}
+
+/* Deassert the currently active chip select. */
+static void npcm7xx_fiu_deselect(NPCM7xxFIUState *s)
+{
+    if (s->active_cs < 0) {
+        return;
+    }
+
+    trace_npcm7xx_fiu_deselect(DEVICE(s)->canonical_path, s->active_cs);
+
+    qemu_irq_raise(s->cs_lines[s->active_cs]);
+    s->active_cs = -1;
+}
+
+/* Direct flash memory read handler. */
+static uint64_t npcm7xx_fiu_flash_read(void *opaque, hwaddr addr,
+                                       unsigned int size)
+{
+    NPCM7xxFIUFlash *f = opaque;
+    NPCM7xxFIUState *fiu = f->fiu;
+    uint64_t value = 0;
+    uint32_t drd_cfg;
+    int dummy_cycles;
+    int i;
+
+    if (fiu->active_cs != -1) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: direct flash read with CS%d already active",
+                      DEVICE(fiu)->canonical_path, fiu->active_cs);
+    }
+
+    npcm7xx_fiu_select(fiu, npcm7xx_fiu_cs_index(fiu, f));
+
+    drd_cfg = fiu->regs[NPCM7XX_FIU_DRD_CFG];
+    ssi_transfer(fiu->spi, FIU_DRD_CFG_RDCMD(drd_cfg));
+
+    switch (FIU_DRD_CFG_ADDSIZ(drd_cfg)) {
+    case FIU_ADDSIZ_4BYTES:
+        ssi_transfer(fiu->spi, extract32(addr, 24, 8));
+        /* fall through */
+    case FIU_ADDSIZ_3BYTES:
+        ssi_transfer(fiu->spi, extract32(addr, 16, 8));
+        ssi_transfer(fiu->spi, extract32(addr, 8, 8));
+        ssi_transfer(fiu->spi, extract32(addr, 0, 8));
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: bad address size %d\n",
+                      DEVICE(fiu)->canonical_path, FIU_DRD_CFG_ADDSIZ(drd_cfg));
+        break;
+    }
+
+    /* Flash chip model expects one transfer per dummy bit, not byte */
+    dummy_cycles =
+        (FIU_DRD_CFG_DBW(drd_cfg) * 8) >> FIU_DRD_CFG_ACCTYPE(drd_cfg);
+    for (i = 0; i < dummy_cycles; i++) {
+        ssi_transfer(fiu->spi, 0);
+    }
+
+    for (i = 0; i < size; i++) {
+        value = deposit64(value, 8 * i, 8, ssi_transfer(fiu->spi, 0));
+    }
+
+    trace_npcm7xx_fiu_flash_read(DEVICE(fiu)->canonical_path, fiu->active_cs,
+                                 addr, size, value);
+
+    npcm7xx_fiu_deselect(fiu);
+
+    return value;
+}
+
+/* Direct flash memory write handler. */
+static void npcm7xx_fiu_flash_write(void *opaque, hwaddr addr, uint64_t v,
+                                    unsigned int size)
+{
+    NPCM7xxFIUFlash *f = opaque;
+    NPCM7xxFIUState *fiu = f->fiu;
+    uint32_t dwr_cfg;
+    int cs_id;
+    int i;
+
+    if (fiu->active_cs != -1) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: direct flash write with CS%d already active",
+                      DEVICE(fiu)->canonical_path, fiu->active_cs);
+    }
+
+    cs_id = npcm7xx_fiu_cs_index(fiu, f);
+    trace_npcm7xx_fiu_flash_write(DEVICE(fiu)->canonical_path, cs_id, addr,
+                                  size, v);
+    npcm7xx_fiu_select(fiu, cs_id);
+
+    dwr_cfg = fiu->regs[NPCM7XX_FIU_DWR_CFG];
+    ssi_transfer(fiu->spi, FIU_DWR_CFG_WRCMD(dwr_cfg));
+
+    switch (FIU_DWR_CFG_ADDSIZ(dwr_cfg)) {
+    case FIU_ADDSIZ_4BYTES:
+        ssi_transfer(fiu->spi, extract32(addr, 24, 8));
+        /* fall through */
+    case FIU_ADDSIZ_3BYTES:
+        ssi_transfer(fiu->spi, extract32(addr, 16, 8));
+        ssi_transfer(fiu->spi, extract32(addr, 8, 8));
+        ssi_transfer(fiu->spi, extract32(addr, 0, 8));
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: bad address size %d\n",
+                      DEVICE(fiu)->canonical_path, FIU_DWR_CFG_ADDSIZ(dwr_cfg));
+        break;
+    }
+
+    for (i = 0; i < size; i++) {
+        ssi_transfer(fiu->spi, extract64(v, i * 8, 8));
+    }
+
+    npcm7xx_fiu_deselect(fiu);
+}
+
+static const MemoryRegionOps npcm7xx_fiu_flash_ops = {
+    .read = npcm7xx_fiu_flash_read,
+    .write = npcm7xx_fiu_flash_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 8,
+        .unaligned = true,
+    },
+};
+
+/* Control register read handler. */
+static uint64_t npcm7xx_fiu_ctrl_read(void *opaque, hwaddr addr,
+                                      unsigned int size)
+{
+    hwaddr reg = addr / sizeof(uint32_t);
+    NPCM7xxFIUState *s = opaque;
+    uint32_t value;
+
+    if (reg < NPCM7XX_FIU_NR_REGS) {
+        value = s->regs[reg];
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: read from invalid offset 0x%" PRIx64 "\n",
+                      DEVICE(s)->canonical_path, addr);
+        value = 0;
+    }
+
+    trace_npcm7xx_fiu_ctrl_read(DEVICE(s)->canonical_path, addr, value);
+
+    return value;
+}
+
+/* Send the specified number of address bytes from the UMA address register. */
+static void send_address(SSIBus *spi, unsigned int addsiz, uint32_t addr)
+{
+    switch (addsiz) {
+    case 4:
+        ssi_transfer(spi, extract32(addr, 24, 8));
+        /* fall through */
+    case 3:
+        ssi_transfer(spi, extract32(addr, 16, 8));
+        /* fall through */
+    case 2:
+        ssi_transfer(spi, extract32(addr, 8, 8));
+        /* fall through */
+    case 1:
+        ssi_transfer(spi, extract32(addr, 0, 8));
+        /* fall through */
+    case 0:
+        break;
+    }
+}
+
+/* Send the number of dummy bits specified in the UMA config register. */
+static void send_dummy_bits(SSIBus *spi, uint32_t uma_cfg, uint32_t uma_cmd)
+{
+    unsigned int bits_per_clock = 1U << FIU_UMA_CFG_DBPCK(uma_cfg);
+    unsigned int i;
+
+    for (i = 0; i < FIU_UMA_CFG_DBSIZ(uma_cfg); i++) {
+        /* Use bytes 0 and 1 first, then keep repeating byte 2 */
+        unsigned int field = (i < 2) ? ((i + 1) * 8) : 24;
+        unsigned int j;
+
+        for (j = 0; j < 8; j += bits_per_clock) {
+            ssi_transfer(spi, extract32(uma_cmd, field + j, bits_per_clock));
+        }
+    }
+}
+
+/* Perform a User-Mode Access transaction. */
+static void npcm7xx_fiu_uma_transaction(NPCM7xxFIUState *s)
+{
+    uint32_t uma_cts = s->regs[NPCM7XX_FIU_UMA_CTS];
+    uint32_t uma_cfg;
+    unsigned int i;
+
+    /* SW_CS means the CS is already forced low, so don't touch it. */
+    if (uma_cts & FIU_UMA_CTS_SW_CS) {
+        int cs_id = FIU_UMA_CTS_DEV_NUM(s->regs[NPCM7XX_FIU_UMA_CTS]);
+        npcm7xx_fiu_select(s, cs_id);
+    }
+
+    /* Send command, if present. */
+    uma_cfg = s->regs[NPCM7XX_FIU_UMA_CFG];
+    if (FIU_UMA_CFG_CMDSIZ(uma_cfg) > 0) {
+        ssi_transfer(s->spi, extract32(s->regs[NPCM7XX_FIU_UMA_CMD], 0, 8));
+    }
+
+    /* Send address, if present. */
+    send_address(s->spi, FIU_UMA_CFG_ADDSIZ(uma_cfg),
+                 s->regs[NPCM7XX_FIU_UMA_ADDR]);
+
+    /* Write data, if present. */
+    for (i = 0; i < FIU_UMA_CFG_WDATSIZ(uma_cfg); i++) {
+        unsigned int reg =
+            (i < 16) ? (NPCM7XX_FIU_UMA_DW0 + i / 4) : NPCM7XX_FIU_UMA_DW3;
+        unsigned int field = (i % 4) * 8;
+
+        ssi_transfer(s->spi, extract32(s->regs[reg], field, 8));
+    }
+
+    /* Send dummy bits, if present. */
+    send_dummy_bits(s->spi, uma_cfg, s->regs[NPCM7XX_FIU_UMA_CMD]);
+
+    /* Read data, if present. */
+    for (i = 0; i < FIU_UMA_CFG_RDATSIZ(uma_cfg); i++) {
+        unsigned int reg = NPCM7XX_FIU_UMA_DR0 + i / 4;
+        unsigned int field = (i % 4) * 8;
+        uint8_t c;
+
+        c = ssi_transfer(s->spi, 0);
+        if (reg <= NPCM7XX_FIU_UMA_DR3) {
+            s->regs[reg] = deposit32(s->regs[reg], field, 8, c);
+        }
+    }
+
+    /* Again, don't touch CS if the user is forcing it low. */
+    if (uma_cts & FIU_UMA_CTS_SW_CS) {
+        npcm7xx_fiu_deselect(s);
+    }
+
+    /* RDYST means a command has completed since it was cleared. */
+    s->regs[NPCM7XX_FIU_UMA_CTS] |= FIU_UMA_CTS_RDYST;
+    /* EXEC_DONE means Execute Command / Not Done, so clear it here. */
+    s->regs[NPCM7XX_FIU_UMA_CTS] &= ~FIU_UMA_CTS_EXEC_DONE;
+}
+
+/* Control register write handler. */
+static void npcm7xx_fiu_ctrl_write(void *opaque, hwaddr addr, uint64_t v,
+                                   unsigned int size)
+{
+    hwaddr reg = addr / sizeof(uint32_t);
+    NPCM7xxFIUState *s = opaque;
+    uint32_t value = v;
+
+    trace_npcm7xx_fiu_ctrl_write(DEVICE(s)->canonical_path, addr, value);
+
+    switch (reg) {
+    case NPCM7XX_FIU_UMA_CFG:
+        if (s->regs[reg] & FIU_UMA_CFG_CMMLCK) {
+            value &= ~FIU_UMA_CFG_CMMLCK_MASK;
+            value |= (s->regs[reg] & FIU_UMA_CFG_CMMLCK_MASK);
+        }
+        /* fall through */
+    case NPCM7XX_FIU_DRD_CFG:
+    case NPCM7XX_FIU_DWR_CFG:
+        if (s->regs[reg] & NPCM7XX_FIU_CFG_LCK) {
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "%s: write to locked register @ 0x%" PRIx64 "\n",
+                          DEVICE(s)->canonical_path, addr);
+            return;
+        }
+        s->regs[reg] = value;
+        break;
+
+    case NPCM7XX_FIU_UMA_CTS:
+        if (value & FIU_UMA_CTS_RDYST) {
+            value &= ~FIU_UMA_CTS_RDYST;
+        } else {
+            value |= s->regs[reg] & FIU_UMA_CTS_RDYST;
+        }
+        if ((s->regs[reg] ^ value) & FIU_UMA_CTS_SW_CS) {
+            if (value & FIU_UMA_CTS_SW_CS) {
+                /*
+                 * Don't drop CS if there's a transfer in progress, or we're
+                 * about to start one.
+                 */
+                if (!((value | s->regs[reg]) & FIU_UMA_CTS_EXEC_DONE)) {
+                    npcm7xx_fiu_deselect(s);
+                }
+            } else {
+                int cs_id = FIU_UMA_CTS_DEV_NUM(s->regs[NPCM7XX_FIU_UMA_CTS]);
+                npcm7xx_fiu_select(s, cs_id);
+            }
+        }
+        s->regs[reg] = value | (s->regs[reg] & FIU_UMA_CTS_EXEC_DONE);
+        if (value & FIU_UMA_CTS_EXEC_DONE) {
+            npcm7xx_fiu_uma_transaction(s);
+        }
+        break;
+
+    case NPCM7XX_FIU_UMA_DR0 ... NPCM7XX_FIU_UMA_DR3:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: write to read-only register @ 0x%" PRIx64 "\n",
+                      DEVICE(s)->canonical_path, addr);
+        return;
+
+    case NPCM7XX_FIU_PRT_CFG:
+    case NPCM7XX_FIU_PRT_CMD0 ... NPCM7XX_FIU_PRT_CMD9:
+        qemu_log_mask(LOG_UNIMP, "%s: PRT is not implemented\n", __func__);
+        break;
+
+    case NPCM7XX_FIU_UMA_CMD:
+    case NPCM7XX_FIU_UMA_ADDR:
+    case NPCM7XX_FIU_UMA_DW0 ... NPCM7XX_FIU_UMA_DW3:
+    case NPCM7XX_FIU_CFG:
+        s->regs[reg] = value;
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: write to invalid offset 0x%" PRIx64 "\n",
+                      DEVICE(s)->canonical_path, addr);
+        return;
+    }
+}
+
+static const MemoryRegionOps npcm7xx_fiu_ctrl_ops = {
+    .read = npcm7xx_fiu_ctrl_read,
+    .write = npcm7xx_fiu_ctrl_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 4,
+        .max_access_size = 4,
+        .unaligned = false,
+    },
+};
+
+static void npcm7xx_fiu_enter_reset(Object *obj, ResetType type)
+{
+    NPCM7xxFIUState *s = NPCM7XX_FIU(obj);
+
+    trace_npcm7xx_fiu_enter_reset(DEVICE(obj)->canonical_path, type);
+
+    memset(s->regs, 0, sizeof(s->regs));
+
+    s->regs[NPCM7XX_FIU_DRD_CFG] = 0x0300100b;
+    s->regs[NPCM7XX_FIU_DWR_CFG] = 0x03000002;
+    s->regs[NPCM7XX_FIU_UMA_CFG] = 0x00000400;
+    s->regs[NPCM7XX_FIU_UMA_CTS] = 0x00010000;
+    s->regs[NPCM7XX_FIU_UMA_CMD] = 0x0000000b;
+    s->regs[NPCM7XX_FIU_PRT_CFG] = 0x00000400;
+    s->regs[NPCM7XX_FIU_CFG] = 0x0000000b;
+}
+
+static void npcm7xx_fiu_hold_reset(Object *obj)
+{
+    NPCM7xxFIUState *s = NPCM7XX_FIU(obj);
+    int i;
+
+    trace_npcm7xx_fiu_hold_reset(DEVICE(obj)->canonical_path);
+
+    for (i = 0; i < s->cs_count; i++) {
+        qemu_irq_raise(s->cs_lines[i]);
+    }
+}
+
+static void npcm7xx_fiu_realize(DeviceState *dev, Error **errp)
+{
+    NPCM7xxFIUState *s = NPCM7XX_FIU(dev);
+    SysBusDevice *sbd = &s->parent;
+    int i;
+
+    if (s->cs_count <= 0) {
+        error_setg(errp, "%s: %d chip selects specified, need at least one",
+                   dev->canonical_path, s->cs_count);
+        return;
+    }
+
+    s->spi = ssi_create_bus(dev, "spi");
+    s->cs_lines = g_new0(qemu_irq, s->cs_count);
+    qdev_init_gpio_out_named(DEVICE(s), s->cs_lines, "cs", s->cs_count);
+    s->flash = g_new0(NPCM7xxFIUFlash, s->cs_count);
+
+    /*
+     * Register the control registers region first. It may be followed by one
+     * or more direct flash access regions.
+     */
+    memory_region_init_io(&s->mmio, OBJECT(s), &npcm7xx_fiu_ctrl_ops, s, "ctrl",
+                          NPCM7XX_FIU_CTRL_REGS_SIZE);
+    sysbus_init_mmio(sbd, &s->mmio);
+
+    for (i = 0; i < s->cs_count; i++) {
+        NPCM7xxFIUFlash *flash = &s->flash[i];
+        flash->fiu = s;
+        memory_region_init_io(&flash->direct_access, OBJECT(s),
+                              &npcm7xx_fiu_flash_ops, &s->flash[i], "flash",
+                              NPCM7XX_FIU_FLASH_WINDOW_SIZE);
+        sysbus_init_mmio(sbd, &flash->direct_access);
+    }
+}
+
+static const VMStateDescription vmstate_npcm7xx_fiu = {
+    .name = "npcm7xx-fiu",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_INT32(active_cs, NPCM7xxFIUState),
+        VMSTATE_UINT32_ARRAY(regs, NPCM7xxFIUState, NPCM7XX_FIU_NR_REGS),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static Property npcm7xx_fiu_properties[] = {
+    DEFINE_PROP_INT32("cs-count", NPCM7xxFIUState, cs_count, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void npcm7xx_fiu_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    QEMU_BUILD_BUG_ON(NPCM7XX_FIU_REGS_END > NPCM7XX_FIU_NR_REGS);
+
+    dc->desc = "NPCM7xx Flash Interface Unit";
+    dc->realize = npcm7xx_fiu_realize;
+    dc->vmsd = &vmstate_npcm7xx_fiu;
+    rc->phases.enter = npcm7xx_fiu_enter_reset;
+    rc->phases.hold = npcm7xx_fiu_hold_reset;
+    device_class_set_props(dc, npcm7xx_fiu_properties);
+}
+
+static const TypeInfo npcm7xx_fiu_types[] = {
+    {
+        .name = TYPE_NPCM7XX_FIU,
+        .parent = TYPE_SYS_BUS_DEVICE,
+        .instance_size = sizeof(NPCM7xxFIUState),
+        .class_init = npcm7xx_fiu_class_init,
+    },
+};
+DEFINE_TYPES(npcm7xx_fiu_types);
diff --git a/hw/ssi/trace-events b/hw/ssi/trace-events
index 0ea498de91..2f83ef833f 100644
--- a/hw/ssi/trace-events
+++ b/hw/ssi/trace-events
@@ -9,3 +9,14 @@ aspeed_smc_dma_checksum(uint32_t addr, uint32_t data) "0x%08x: 0x%08x"
 aspeed_smc_dma_rw(const char *dir, uint32_t flash_addr, uint32_t dram_addr, uint32_t size) "%s flash:@0x%08x dram:@0x%08x size:0x%08x"
 aspeed_smc_write(uint64_t addr,  uint32_t size, uint64_t data) "@0x%" PRIx64 " size %u: 0x%" PRIx64
 aspeed_smc_flash_select(int cs, const char *prefix) "CS%d %sselect"
+
+# npcm7xx_fiu.c
+
+npcm7xx_fiu_enter_reset(const char *id, int reset_type) "%s reset type: %d"
+npcm7xx_fiu_hold_reset(const char *id) "%s"
+npcm7xx_fiu_select(const char *id, int cs) "%s select CS%d"
+npcm7xx_fiu_deselect(const char *id, int cs) "%s deselect CS%d"
+npcm7xx_fiu_ctrl_read(const char *id, uint64_t addr, uint32_t data) "%s offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+npcm7xx_fiu_ctrl_write(const char *id, uint64_t addr, uint32_t data) "%s offset: 0x%04" PRIx64 " value: 0x%08" PRIx32
+npcm7xx_fiu_flash_read(const char *id, int cs, uint64_t addr, unsigned int size, uint64_t value) "%s[%d] offset: 0x%08" PRIx64 " size: %u value: 0x%" PRIx64
+npcm7xx_fiu_flash_write(const char *id, int cs, uint64_t addr, unsigned int size, uint64_t value) "%s[%d] offset: 0x%08" PRIx64 " size: %u value: 0x%" PRIx64
diff --git a/hw/timer/armv7m_systick.c b/hw/timer/armv7m_systick.c
index 74c58bcf24..a8cec7eb56 100644
--- a/hw/timer/armv7m_systick.c
+++ b/hw/timer/armv7m_systick.c
@@ -202,6 +202,14 @@ static void systick_reset(DeviceState *dev)
 {
     SysTickState *s = SYSTICK(dev);
 
+    /*
+     * Forgetting to set system_clock_scale is always a board code
+     * bug. We can't check this earlier because for some boards
+     * (like stellaris) it is not yet configured at the point where
+     * the systick device is realized.
+     */
+    assert(system_clock_scale != 0);
+
     s->control = 0;
     s->reload = 0;
     s->tick = 0;
diff --git a/hw/timer/meson.build b/hw/timer/meson.build
index 9f0a267c83..be343f68fe 100644
--- a/hw/timer/meson.build
+++ b/hw/timer/meson.build
@@ -23,6 +23,7 @@ softmmu_ss.add(when: 'CONFIG_LM32', if_true: files('lm32_timer.c'))
 softmmu_ss.add(when: 'CONFIG_MILKYMIST', if_true: files('milkymist-sysctl.c'))
 softmmu_ss.add(when: 'CONFIG_MIPS_CPS', if_true: files('mips_gictimer.c'))
 softmmu_ss.add(when: 'CONFIG_MSF2', if_true: files('mss-timer.c'))
+softmmu_ss.add(when: 'CONFIG_NPCM7XX', if_true: files('npcm7xx_timer.c'))
 softmmu_ss.add(when: 'CONFIG_NRF51_SOC', if_true: files('nrf51_timer.c'))
 softmmu_ss.add(when: 'CONFIG_OMAP', if_true: files('omap_gptimer.c'))
 softmmu_ss.add(when: 'CONFIG_OMAP', if_true: files('omap_synctimer.c'))
diff --git a/hw/timer/npcm7xx_timer.c b/hw/timer/npcm7xx_timer.c
new file mode 100644
index 0000000000..5703e43d40
--- /dev/null
+++ b/hw/timer/npcm7xx_timer.c
@@ -0,0 +1,543 @@
+/*
+ * Nuvoton NPCM7xx Timer Controller
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/irq.h"
+#include "hw/misc/npcm7xx_clk.h"
+#include "hw/timer/npcm7xx_timer.h"
+#include "migration/vmstate.h"
+#include "qemu/bitops.h"
+#include "qemu/error-report.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "qemu/timer.h"
+#include "qemu/units.h"
+#include "trace.h"
+
+/* 32-bit register indices. */
+enum NPCM7xxTimerRegisters {
+    NPCM7XX_TIMER_TCSR0,
+    NPCM7XX_TIMER_TCSR1,
+    NPCM7XX_TIMER_TICR0,
+    NPCM7XX_TIMER_TICR1,
+    NPCM7XX_TIMER_TDR0,
+    NPCM7XX_TIMER_TDR1,
+    NPCM7XX_TIMER_TISR,
+    NPCM7XX_TIMER_WTCR,
+    NPCM7XX_TIMER_TCSR2,
+    NPCM7XX_TIMER_TCSR3,
+    NPCM7XX_TIMER_TICR2,
+    NPCM7XX_TIMER_TICR3,
+    NPCM7XX_TIMER_TDR2,
+    NPCM7XX_TIMER_TDR3,
+    NPCM7XX_TIMER_TCSR4         = 0x0040 / sizeof(uint32_t),
+    NPCM7XX_TIMER_TICR4         = 0x0048 / sizeof(uint32_t),
+    NPCM7XX_TIMER_TDR4          = 0x0050 / sizeof(uint32_t),
+    NPCM7XX_TIMER_REGS_END,
+};
+
+/* Register field definitions. */
+#define NPCM7XX_TCSR_CEN                BIT(30)
+#define NPCM7XX_TCSR_IE                 BIT(29)
+#define NPCM7XX_TCSR_PERIODIC           BIT(27)
+#define NPCM7XX_TCSR_CRST               BIT(26)
+#define NPCM7XX_TCSR_CACT               BIT(25)
+#define NPCM7XX_TCSR_RSVD               0x01ffff00
+#define NPCM7XX_TCSR_PRESCALE_START     0
+#define NPCM7XX_TCSR_PRESCALE_LEN       8
+
+/*
+ * Returns the index of timer in the tc->timer array. This can be used to
+ * locate the registers that belong to this timer.
+ */
+static int npcm7xx_timer_index(NPCM7xxTimerCtrlState *tc, NPCM7xxTimer *timer)
+{
+    int index = timer - tc->timer;
+
+    g_assert(index >= 0 && index < NPCM7XX_TIMERS_PER_CTRL);
+
+    return index;
+}
+
+/* Return the value by which to divide the reference clock rate. */
+static uint32_t npcm7xx_tcsr_prescaler(uint32_t tcsr)
+{
+    return extract32(tcsr, NPCM7XX_TCSR_PRESCALE_START,
+                     NPCM7XX_TCSR_PRESCALE_LEN) + 1;
+}
+
+/* Convert a timer cycle count to a time interval in nanoseconds. */
+static int64_t npcm7xx_timer_count_to_ns(NPCM7xxTimer *t, uint32_t count)
+{
+    int64_t ns = count;
+
+    ns *= NANOSECONDS_PER_SECOND / NPCM7XX_TIMER_REF_HZ;
+    ns *= npcm7xx_tcsr_prescaler(t->tcsr);
+
+    return ns;
+}
+
+/* Convert a time interval in nanoseconds to a timer cycle count. */
+static uint32_t npcm7xx_timer_ns_to_count(NPCM7xxTimer *t, int64_t ns)
+{
+    int64_t count;
+
+    count = ns / (NANOSECONDS_PER_SECOND / NPCM7XX_TIMER_REF_HZ);
+    count /= npcm7xx_tcsr_prescaler(t->tcsr);
+
+    return count;
+}
+
+/*
+ * Raise the interrupt line if there's a pending interrupt and interrupts are
+ * enabled for this timer. If not, lower it.
+ */
+static void npcm7xx_timer_check_interrupt(NPCM7xxTimer *t)
+{
+    NPCM7xxTimerCtrlState *tc = t->ctrl;
+    int index = npcm7xx_timer_index(tc, t);
+    bool pending = (t->tcsr & NPCM7XX_TCSR_IE) && (tc->tisr & BIT(index));
+
+    qemu_set_irq(t->irq, pending);
+    trace_npcm7xx_timer_irq(DEVICE(tc)->canonical_path, index, pending);
+}
+
+/* Start or resume the timer. */
+static void npcm7xx_timer_start(NPCM7xxTimer *t)
+{
+    int64_t now;
+
+    now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    t->expires_ns = now + t->remaining_ns;
+    timer_mod(&t->qtimer, t->expires_ns);
+}
+
+/*
+ * Called when the counter reaches zero. Sets the interrupt flag, and either
+ * restarts or disables the timer.
+ */
+static void npcm7xx_timer_reached_zero(NPCM7xxTimer *t)
+{
+    NPCM7xxTimerCtrlState *tc = t->ctrl;
+    int index = npcm7xx_timer_index(tc, t);
+
+    tc->tisr |= BIT(index);
+
+    if (t->tcsr & NPCM7XX_TCSR_PERIODIC) {
+        t->remaining_ns = npcm7xx_timer_count_to_ns(t, t->ticr);
+        if (t->tcsr & NPCM7XX_TCSR_CEN) {
+            npcm7xx_timer_start(t);
+        }
+    } else {
+        t->tcsr &= ~(NPCM7XX_TCSR_CEN | NPCM7XX_TCSR_CACT);
+    }
+
+    npcm7xx_timer_check_interrupt(t);
+}
+
+/* Stop counting. Record the time remaining so we can continue later. */
+static void npcm7xx_timer_pause(NPCM7xxTimer *t)
+{
+    int64_t now;
+
+    timer_del(&t->qtimer);
+    now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+    t->remaining_ns = t->expires_ns - now;
+    if (t->remaining_ns <= 0) {
+        npcm7xx_timer_reached_zero(t);
+    }
+}
+
+/*
+ * Restart the timer from its initial value. If the timer was enabled and stays
+ * enabled, adjust the QEMU timer according to the new count. If the timer is
+ * transitioning from disabled to enabled, the caller is expected to start the
+ * timer later.
+ */
+static void npcm7xx_timer_restart(NPCM7xxTimer *t, uint32_t old_tcsr)
+{
+    t->remaining_ns = npcm7xx_timer_count_to_ns(t, t->ticr);
+
+    if (old_tcsr & t->tcsr & NPCM7XX_TCSR_CEN) {
+        npcm7xx_timer_start(t);
+    }
+}
+
+/* Register read and write handlers */
+
+static uint32_t npcm7xx_timer_read_tdr(NPCM7xxTimer *t)
+{
+    if (t->tcsr & NPCM7XX_TCSR_CEN) {
+        int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
+
+        return npcm7xx_timer_ns_to_count(t, t->expires_ns - now);
+    }
+
+    return npcm7xx_timer_ns_to_count(t, t->remaining_ns);
+}
+
+static void npcm7xx_timer_write_tcsr(NPCM7xxTimer *t, uint32_t new_tcsr)
+{
+    uint32_t old_tcsr = t->tcsr;
+    uint32_t tdr;
+
+    if (new_tcsr & NPCM7XX_TCSR_RSVD) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: reserved bits in 0x%08x ignored\n",
+                      __func__, new_tcsr);
+        new_tcsr &= ~NPCM7XX_TCSR_RSVD;
+    }
+    if (new_tcsr & NPCM7XX_TCSR_CACT) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: read-only bits in 0x%08x ignored\n",
+                      __func__, new_tcsr);
+        new_tcsr &= ~NPCM7XX_TCSR_CACT;
+    }
+    if ((new_tcsr & NPCM7XX_TCSR_CRST) && (new_tcsr & NPCM7XX_TCSR_CEN)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: both CRST and CEN set; ignoring CEN.\n",
+                      __func__);
+        new_tcsr &= ~NPCM7XX_TCSR_CEN;
+    }
+
+    /* Calculate the value of TDR before potentially changing the prescaler. */
+    tdr = npcm7xx_timer_read_tdr(t);
+
+    t->tcsr = (t->tcsr & NPCM7XX_TCSR_CACT) | new_tcsr;
+
+    if (npcm7xx_tcsr_prescaler(old_tcsr) != npcm7xx_tcsr_prescaler(new_tcsr)) {
+        /* Recalculate time remaining based on the current TDR value. */
+        t->remaining_ns = npcm7xx_timer_count_to_ns(t, tdr);
+        if (old_tcsr & t->tcsr & NPCM7XX_TCSR_CEN) {
+            npcm7xx_timer_start(t);
+        }
+    }
+
+    if ((old_tcsr ^ new_tcsr) & NPCM7XX_TCSR_IE) {
+        npcm7xx_timer_check_interrupt(t);
+    }
+    if (new_tcsr & NPCM7XX_TCSR_CRST) {
+        npcm7xx_timer_restart(t, old_tcsr);
+        t->tcsr &= ~NPCM7XX_TCSR_CRST;
+    }
+    if ((old_tcsr ^ new_tcsr) & NPCM7XX_TCSR_CEN) {
+        if (new_tcsr & NPCM7XX_TCSR_CEN) {
+            t->tcsr |= NPCM7XX_TCSR_CACT;
+            npcm7xx_timer_start(t);
+        } else {
+            t->tcsr &= ~NPCM7XX_TCSR_CACT;
+            npcm7xx_timer_pause(t);
+        }
+    }
+}
+
+static void npcm7xx_timer_write_ticr(NPCM7xxTimer *t, uint32_t new_ticr)
+{
+    t->ticr = new_ticr;
+
+    npcm7xx_timer_restart(t, t->tcsr);
+}
+
+static void npcm7xx_timer_write_tisr(NPCM7xxTimerCtrlState *s, uint32_t value)
+{
+    int i;
+
+    s->tisr &= ~value;
+    for (i = 0; i < ARRAY_SIZE(s->timer); i++) {
+        if (value & (1U << i)) {
+            npcm7xx_timer_check_interrupt(&s->timer[i]);
+        }
+    }
+}
+
+static hwaddr npcm7xx_tcsr_index(hwaddr reg)
+{
+    switch (reg) {
+    case NPCM7XX_TIMER_TCSR0:
+        return 0;
+    case NPCM7XX_TIMER_TCSR1:
+        return 1;
+    case NPCM7XX_TIMER_TCSR2:
+        return 2;
+    case NPCM7XX_TIMER_TCSR3:
+        return 3;
+    case NPCM7XX_TIMER_TCSR4:
+        return 4;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static hwaddr npcm7xx_ticr_index(hwaddr reg)
+{
+    switch (reg) {
+    case NPCM7XX_TIMER_TICR0:
+        return 0;
+    case NPCM7XX_TIMER_TICR1:
+        return 1;
+    case NPCM7XX_TIMER_TICR2:
+        return 2;
+    case NPCM7XX_TIMER_TICR3:
+        return 3;
+    case NPCM7XX_TIMER_TICR4:
+        return 4;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static hwaddr npcm7xx_tdr_index(hwaddr reg)
+{
+    switch (reg) {
+    case NPCM7XX_TIMER_TDR0:
+        return 0;
+    case NPCM7XX_TIMER_TDR1:
+        return 1;
+    case NPCM7XX_TIMER_TDR2:
+        return 2;
+    case NPCM7XX_TIMER_TDR3:
+        return 3;
+    case NPCM7XX_TIMER_TDR4:
+        return 4;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+static uint64_t npcm7xx_timer_read(void *opaque, hwaddr offset, unsigned size)
+{
+    NPCM7xxTimerCtrlState *s = opaque;
+    uint64_t value = 0;
+    hwaddr reg;
+
+    reg = offset / sizeof(uint32_t);
+    switch (reg) {
+    case NPCM7XX_TIMER_TCSR0:
+    case NPCM7XX_TIMER_TCSR1:
+    case NPCM7XX_TIMER_TCSR2:
+    case NPCM7XX_TIMER_TCSR3:
+    case NPCM7XX_TIMER_TCSR4:
+        value = s->timer[npcm7xx_tcsr_index(reg)].tcsr;
+        break;
+
+    case NPCM7XX_TIMER_TICR0:
+    case NPCM7XX_TIMER_TICR1:
+    case NPCM7XX_TIMER_TICR2:
+    case NPCM7XX_TIMER_TICR3:
+    case NPCM7XX_TIMER_TICR4:
+        value = s->timer[npcm7xx_ticr_index(reg)].ticr;
+        break;
+
+    case NPCM7XX_TIMER_TDR0:
+    case NPCM7XX_TIMER_TDR1:
+    case NPCM7XX_TIMER_TDR2:
+    case NPCM7XX_TIMER_TDR3:
+    case NPCM7XX_TIMER_TDR4:
+        value = npcm7xx_timer_read_tdr(&s->timer[npcm7xx_tdr_index(reg)]);
+        break;
+
+    case NPCM7XX_TIMER_TISR:
+        value = s->tisr;
+        break;
+
+    case NPCM7XX_TIMER_WTCR:
+        value = s->wtcr;
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: invalid offset 0x%04" HWADDR_PRIx "\n",
+                      __func__, offset);
+        break;
+    }
+
+    trace_npcm7xx_timer_read(DEVICE(s)->canonical_path, offset, value);
+
+    return value;
+}
+
+static void npcm7xx_timer_write(void *opaque, hwaddr offset,
+                                uint64_t v, unsigned size)
+{
+    uint32_t reg = offset / sizeof(uint32_t);
+    NPCM7xxTimerCtrlState *s = opaque;
+    uint32_t value = v;
+
+    trace_npcm7xx_timer_write(DEVICE(s)->canonical_path, offset, value);
+
+    switch (reg) {
+    case NPCM7XX_TIMER_TCSR0:
+    case NPCM7XX_TIMER_TCSR1:
+    case NPCM7XX_TIMER_TCSR2:
+    case NPCM7XX_TIMER_TCSR3:
+    case NPCM7XX_TIMER_TCSR4:
+        npcm7xx_timer_write_tcsr(&s->timer[npcm7xx_tcsr_index(reg)], value);
+        return;
+
+    case NPCM7XX_TIMER_TICR0:
+    case NPCM7XX_TIMER_TICR1:
+    case NPCM7XX_TIMER_TICR2:
+    case NPCM7XX_TIMER_TICR3:
+    case NPCM7XX_TIMER_TICR4:
+        npcm7xx_timer_write_ticr(&s->timer[npcm7xx_ticr_index(reg)], value);
+        return;
+
+    case NPCM7XX_TIMER_TDR0:
+    case NPCM7XX_TIMER_TDR1:
+    case NPCM7XX_TIMER_TDR2:
+    case NPCM7XX_TIMER_TDR3:
+    case NPCM7XX_TIMER_TDR4:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: register @ 0x%04" HWADDR_PRIx " is read-only\n",
+                      __func__, offset);
+        return;
+
+    case NPCM7XX_TIMER_TISR:
+        npcm7xx_timer_write_tisr(s, value);
+        return;
+
+    case NPCM7XX_TIMER_WTCR:
+        qemu_log_mask(LOG_UNIMP, "%s: WTCR write not implemented: 0x%08x\n",
+                      __func__, value);
+        return;
+    }
+
+    qemu_log_mask(LOG_GUEST_ERROR,
+                  "%s: invalid offset 0x%04" HWADDR_PRIx "\n",
+                  __func__, offset);
+}
+
+static const struct MemoryRegionOps npcm7xx_timer_ops = {
+    .read       = npcm7xx_timer_read,
+    .write      = npcm7xx_timer_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid      = {
+        .min_access_size        = 4,
+        .max_access_size        = 4,
+        .unaligned              = false,
+    },
+};
+
+/* Called when the QEMU timer expires. */
+static void npcm7xx_timer_expired(void *opaque)
+{
+    NPCM7xxTimer *t = opaque;
+
+    if (t->tcsr & NPCM7XX_TCSR_CEN) {
+        npcm7xx_timer_reached_zero(t);
+    }
+}
+
+static void npcm7xx_timer_enter_reset(Object *obj, ResetType type)
+{
+    NPCM7xxTimerCtrlState *s = NPCM7XX_TIMER(obj);
+    int i;
+
+    for (i = 0; i < NPCM7XX_TIMERS_PER_CTRL; i++) {
+        NPCM7xxTimer *t = &s->timer[i];
+
+        timer_del(&t->qtimer);
+        t->expires_ns = 0;
+        t->remaining_ns = 0;
+        t->tcsr = 0x00000005;
+        t->ticr = 0x00000000;
+    }
+
+    s->tisr = 0x00000000;
+    s->wtcr = 0x00000400;
+}
+
+static void npcm7xx_timer_hold_reset(Object *obj)
+{
+    NPCM7xxTimerCtrlState *s = NPCM7XX_TIMER(obj);
+    int i;
+
+    for (i = 0; i < NPCM7XX_TIMERS_PER_CTRL; i++) {
+        qemu_irq_lower(s->timer[i].irq);
+    }
+}
+
+static void npcm7xx_timer_realize(DeviceState *dev, Error **errp)
+{
+    NPCM7xxTimerCtrlState *s = NPCM7XX_TIMER(dev);
+    SysBusDevice *sbd = &s->parent;
+    int i;
+
+    for (i = 0; i < NPCM7XX_TIMERS_PER_CTRL; i++) {
+        NPCM7xxTimer *t = &s->timer[i];
+        t->ctrl = s;
+        timer_init_ns(&t->qtimer, QEMU_CLOCK_VIRTUAL, npcm7xx_timer_expired, t);
+        sysbus_init_irq(sbd, &t->irq);
+    }
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &npcm7xx_timer_ops, s,
+                          TYPE_NPCM7XX_TIMER, 4 * KiB);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static const VMStateDescription vmstate_npcm7xx_timer = {
+    .name = "npcm7xx-timer",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_TIMER(qtimer, NPCM7xxTimer),
+        VMSTATE_INT64(expires_ns, NPCM7xxTimer),
+        VMSTATE_INT64(remaining_ns, NPCM7xxTimer),
+        VMSTATE_UINT32(tcsr, NPCM7xxTimer),
+        VMSTATE_UINT32(ticr, NPCM7xxTimer),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static const VMStateDescription vmstate_npcm7xx_timer_ctrl = {
+    .name = "npcm7xx-timer-ctrl",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(tisr, NPCM7xxTimerCtrlState),
+        VMSTATE_UINT32(wtcr, NPCM7xxTimerCtrlState),
+        VMSTATE_STRUCT_ARRAY(timer, NPCM7xxTimerCtrlState,
+                             NPCM7XX_TIMERS_PER_CTRL, 0, vmstate_npcm7xx_timer,
+                             NPCM7xxTimer),
+        VMSTATE_END_OF_LIST(),
+    },
+};
+
+static void npcm7xx_timer_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    QEMU_BUILD_BUG_ON(NPCM7XX_TIMER_REGS_END > NPCM7XX_TIMER_NR_REGS);
+
+    dc->desc = "NPCM7xx Timer Controller";
+    dc->realize = npcm7xx_timer_realize;
+    dc->vmsd = &vmstate_npcm7xx_timer_ctrl;
+    rc->phases.enter = npcm7xx_timer_enter_reset;
+    rc->phases.hold = npcm7xx_timer_hold_reset;
+}
+
+static const TypeInfo npcm7xx_timer_info = {
+    .name               = TYPE_NPCM7XX_TIMER,
+    .parent             = TYPE_SYS_BUS_DEVICE,
+    .instance_size      = sizeof(NPCM7xxTimerCtrlState),
+    .class_init         = npcm7xx_timer_class_init,
+};
+
+static void npcm7xx_timer_register_type(void)
+{
+    type_register_static(&npcm7xx_timer_info);
+}
+type_init(npcm7xx_timer_register_type);
diff --git a/hw/timer/trace-events b/hw/timer/trace-events
index 1537c3e6ec..b996d99200 100644
--- a/hw/timer/trace-events
+++ b/hw/timer/trace-events
@@ -66,6 +66,11 @@ cmsdk_apb_dualtimer_read(uint64_t offset, uint64_t data, unsigned size) "CMSDK A
 cmsdk_apb_dualtimer_write(uint64_t offset, uint64_t data, unsigned size) "CMSDK APB dualtimer write: offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
 cmsdk_apb_dualtimer_reset(void) "CMSDK APB dualtimer: reset"
 
+# npcm7xx_timer.c
+npcm7xx_timer_read(const char *id, uint64_t offset, uint64_t value) " %s offset: 0x%04" PRIx64 " value 0x%08" PRIx64
+npcm7xx_timer_write(const char *id, uint64_t offset, uint64_t value) "%s offset: 0x%04" PRIx64 " value 0x%08" PRIx64
+npcm7xx_timer_irq(const char *id, int timer, int state) "%s timer %d state %d"
+
 # nrf51_timer.c
 nrf51_timer_read(uint8_t timer_id, uint64_t addr, uint32_t value, unsigned size) "timer %u read addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"
 nrf51_timer_write(uint8_t timer_id, uint64_t addr, uint32_t value, unsigned size) "timer %u write addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"