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-rw-r--r--hw/misc/Makefile.objs2
-rw-r--r--hw/misc/imx25_ccm.c341
-rw-r--r--hw/misc/imx31_ccm.c392
-rw-r--r--hw/misc/imx_ccm.c231
4 files changed, 757 insertions, 209 deletions
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
index aeb6b7da74..8a235dfb57 100644
--- a/hw/misc/Makefile.objs
+++ b/hw/misc/Makefile.objs
@@ -26,6 +26,8 @@ obj-$(CONFIG_NSERIES) += cbus.o
 obj-$(CONFIG_ECCMEMCTL) += eccmemctl.o
 obj-$(CONFIG_EXYNOS4) += exynos4210_pmu.o
 obj-$(CONFIG_IMX) += imx_ccm.o
+obj-$(CONFIG_IMX) += imx31_ccm.o
+obj-$(CONFIG_IMX) += imx25_ccm.o
 obj-$(CONFIG_MILKYMIST) += milkymist-hpdmc.o
 obj-$(CONFIG_MILKYMIST) += milkymist-pfpu.o
 obj-$(CONFIG_MAINSTONE) += mst_fpga.o
diff --git a/hw/misc/imx25_ccm.c b/hw/misc/imx25_ccm.c
new file mode 100644
index 0000000000..23759ca648
--- /dev/null
+++ b/hw/misc/imx25_ccm.c
@@ -0,0 +1,341 @@
+/*
+ * IMX25 Clock Control Module
+ *
+ * Copyright (C) 2012 NICTA
+ * Updated by Jean-Christophe Dubois <jcd@tribudubois.net>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * To get the timer frequencies right, we need to emulate at least part of
+ * the CCM.
+ */
+
+#include "hw/misc/imx25_ccm.h"
+
+#ifndef DEBUG_IMX25_CCM
+#define DEBUG_IMX25_CCM 0
+#endif
+
+#define DPRINTF(fmt, args...) \
+    do { \
+        if (DEBUG_IMX25_CCM) { \
+            fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX25_CCM, \
+                                             __func__, ##args); \
+        } \
+    } while (0)
+
+static char const *imx25_ccm_reg_name(uint32_t reg)
+{
+    static char unknown[20];
+
+    switch (reg) {
+    case IMX25_CCM_MPCTL_REG:
+        return "mpctl";
+    case IMX25_CCM_UPCTL_REG:
+        return "upctl";
+    case IMX25_CCM_CCTL_REG:
+        return "cctl";
+    case IMX25_CCM_CGCR0_REG:
+        return "cgcr0";
+    case IMX25_CCM_CGCR1_REG:
+        return "cgcr1";
+    case IMX25_CCM_CGCR2_REG:
+        return "cgcr2";
+    case IMX25_CCM_PCDR0_REG:
+        return "pcdr0";
+    case IMX25_CCM_PCDR1_REG:
+        return "pcdr1";
+    case IMX25_CCM_PCDR2_REG:
+        return "pcdr2";
+    case IMX25_CCM_PCDR3_REG:
+        return "pcdr3";
+    case IMX25_CCM_RCSR_REG:
+        return "rcsr";
+    case IMX25_CCM_CRDR_REG:
+        return "crdr";
+    case IMX25_CCM_DCVR0_REG:
+        return "dcvr0";
+    case IMX25_CCM_DCVR1_REG:
+        return "dcvr1";
+    case IMX25_CCM_DCVR2_REG:
+        return "dcvr2";
+    case IMX25_CCM_DCVR3_REG:
+        return "dcvr3";
+    case IMX25_CCM_LTR0_REG:
+        return "ltr0";
+    case IMX25_CCM_LTR1_REG:
+        return "ltr1";
+    case IMX25_CCM_LTR2_REG:
+        return "ltr2";
+    case IMX25_CCM_LTR3_REG:
+        return "ltr3";
+    case IMX25_CCM_LTBR0_REG:
+        return "ltbr0";
+    case IMX25_CCM_LTBR1_REG:
+        return "ltbr1";
+    case IMX25_CCM_PMCR0_REG:
+        return "pmcr0";
+    case IMX25_CCM_PMCR1_REG:
+        return "pmcr1";
+    case IMX25_CCM_PMCR2_REG:
+        return "pmcr2";
+    case IMX25_CCM_MCR_REG:
+        return "mcr";
+    case IMX25_CCM_LPIMR0_REG:
+        return "lpimr0";
+    case IMX25_CCM_LPIMR1_REG:
+        return "lpimr1";
+    default:
+        sprintf(unknown, "[%d ?]", reg);
+        return unknown;
+    }
+}
+#define CKIH_FREQ 24000000 /* 24MHz crystal input */
+
+static const VMStateDescription vmstate_imx25_ccm = {
+    .name = TYPE_IMX25_CCM,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(reg, IMX25CCMState, IMX25_CCM_MAX_REG),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static uint32_t imx25_ccm_get_mpll_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX25CCMState *s = IMX25_CCM(dev);
+
+    if (EXTRACT(s->reg[IMX25_CCM_CCTL_REG], MPLL_BYPASS)) {
+        freq = CKIH_FREQ;
+    } else {
+        freq = imx_ccm_calc_pll(s->reg[IMX25_CCM_MPCTL_REG], CKIH_FREQ);
+    }
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx25_ccm_get_upll_clk(IMXCCMState *dev)
+{
+    uint32_t freq = 0;
+    IMX25CCMState *s = IMX25_CCM(dev);
+
+    if (!EXTRACT(s->reg[IMX25_CCM_CCTL_REG], UPLL_DIS)) {
+        freq = imx_ccm_calc_pll(s->reg[IMX25_CCM_UPCTL_REG], CKIH_FREQ);
+    }
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx25_ccm_get_mcu_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX25CCMState *s = IMX25_CCM(dev);
+
+    freq = imx25_ccm_get_mpll_clk(dev);
+
+    if (EXTRACT(s->reg[IMX25_CCM_CCTL_REG], ARM_SRC)) {
+        freq = (freq * 3 / 4);
+    }
+
+    freq = freq / (1 + EXTRACT(s->reg[IMX25_CCM_CCTL_REG], ARM_CLK_DIV));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx25_ccm_get_ahb_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX25CCMState *s = IMX25_CCM(dev);
+
+    freq = imx25_ccm_get_mcu_clk(dev)
+           / (1 + EXTRACT(s->reg[IMX25_CCM_CCTL_REG], AHB_CLK_DIV));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx25_ccm_get_ipg_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+
+    freq = imx25_ccm_get_ahb_clk(dev) / 2;
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx25_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
+{
+    uint32_t freq = 0;
+    DPRINTF("Clock = %d)\n", clock);
+
+    switch (clock) {
+    case NOCLK:
+        break;
+    case CLK_MPLL:
+        freq = imx25_ccm_get_mpll_clk(dev);
+        break;
+    case CLK_UPLL:
+        freq = imx25_ccm_get_upll_clk(dev);
+        break;
+    case CLK_MCU:
+        freq = imx25_ccm_get_mcu_clk(dev);
+        break;
+    case CLK_AHB:
+        freq = imx25_ccm_get_ahb_clk(dev);
+        break;
+    case CLK_IPG:
+        freq = imx25_ccm_get_ipg_clk(dev);
+        break;
+    case CLK_32k:
+        freq = CKIL_FREQ;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: unsupported clock %d\n",
+                      TYPE_IMX25_CCM, __func__, clock);
+        break;
+    }
+
+    DPRINTF("Clock = %d) = %d\n", clock, freq);
+
+    return freq;
+}
+
+static void imx25_ccm_reset(DeviceState *dev)
+{
+    IMX25CCMState *s = IMX25_CCM(dev);
+
+    DPRINTF("\n");
+
+    memset(s->reg, 0, IMX25_CCM_MAX_REG * sizeof(uint32_t));
+    s->reg[IMX25_CCM_MPCTL_REG] = 0x800b2c01;
+    s->reg[IMX25_CCM_UPCTL_REG] = 0x84042800;
+    /* 
+     * The value below gives:
+     * CPU = 133 MHz, AHB = 66,5 MHz, IPG = 33 MHz. 
+     */
+    s->reg[IMX25_CCM_CCTL_REG]  = 0xd0030000;
+    s->reg[IMX25_CCM_CGCR0_REG] = 0x028A0100;
+    s->reg[IMX25_CCM_CGCR1_REG] = 0x04008100;
+    s->reg[IMX25_CCM_CGCR2_REG] = 0x00000438;
+    s->reg[IMX25_CCM_PCDR0_REG] = 0x01010101;
+    s->reg[IMX25_CCM_PCDR1_REG] = 0x01010101;
+    s->reg[IMX25_CCM_PCDR2_REG] = 0x01010101;
+    s->reg[IMX25_CCM_PCDR3_REG] = 0x01010101;
+    s->reg[IMX25_CCM_PMCR0_REG] = 0x00A00000;
+    s->reg[IMX25_CCM_PMCR1_REG] = 0x0000A030;
+    s->reg[IMX25_CCM_PMCR2_REG] = 0x0000A030;
+    s->reg[IMX25_CCM_MCR_REG]   = 0x43000000;
+
+    /*
+     * default boot will change the reset values to allow:
+     * CPU = 399 MHz, AHB = 133 MHz, IPG = 66,5 MHz. 
+     * For some reason, this doesn't work. With the value below, linux
+     * detects a 88 MHz IPG CLK instead of 66,5 MHz.
+    s->reg[IMX25_CCM_CCTL_REG]  = 0x20032000;
+     */
+}
+
+static uint64_t imx25_ccm_read(void *opaque, hwaddr offset, unsigned size)
+{
+    uint32 value = 0;
+    IMX25CCMState *s = (IMX25CCMState *)opaque;
+
+    if (offset < 0x70) {
+        value = s->reg[offset >> 2];
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+                      HWADDR_PRIx "\n", TYPE_IMX25_CCM, __func__, offset);
+    }
+
+    DPRINTF("reg[%s] => 0x%" PRIx32 "\n", imx25_ccm_reg_name(offset >> 2),
+            value);
+
+    return value;
+}
+
+static void imx25_ccm_write(void *opaque, hwaddr offset, uint64_t value,
+                            unsigned size)
+{
+    IMX25CCMState *s = (IMX25CCMState *)opaque;
+
+    DPRINTF("reg[%s] <= 0x%" PRIx32 "\n", imx25_ccm_reg_name(offset >> 2),
+            (uint32_t)value);
+
+    if (offset < 0x70) {
+        /*
+         * We will do a better implementation later. In particular some bits
+         * cannot be written to.
+         */
+        s->reg[offset >> 2] = value;
+    } else {
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+                      HWADDR_PRIx "\n", TYPE_IMX25_CCM, __func__, offset);
+    }
+}
+
+static const struct MemoryRegionOps imx25_ccm_ops = {
+    .read = imx25_ccm_read,
+    .write = imx25_ccm_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        /*
+         * Our device would not work correctly if the guest was doing
+         * unaligned access. This might not be a limitation on the real
+         * device but in practice there is no reason for a guest to access
+         * this device unaligned.
+         */
+        .min_access_size = 4,
+        .max_access_size = 4,
+        .unaligned = false,
+    },
+};
+
+static void imx25_ccm_init(Object *obj)
+{
+    DeviceState *dev = DEVICE(obj);
+    SysBusDevice *sd = SYS_BUS_DEVICE(obj);
+    IMX25CCMState *s = IMX25_CCM(obj);
+
+    memory_region_init_io(&s->iomem, OBJECT(dev), &imx25_ccm_ops, s,
+                          TYPE_IMX25_CCM, 0x1000);
+    sysbus_init_mmio(sd, &s->iomem);
+}
+
+static void imx25_ccm_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    IMXCCMClass *ccm = IMX_CCM_CLASS(klass);
+
+    dc->reset = imx25_ccm_reset;
+    dc->vmsd = &vmstate_imx25_ccm;
+    dc->desc = "i.MX25 Clock Control Module";
+
+    ccm->get_clock_frequency = imx25_ccm_get_clock_frequency;
+}
+
+static const TypeInfo imx25_ccm_info = {
+    .name          = TYPE_IMX25_CCM,
+    .parent        = TYPE_IMX_CCM,
+    .instance_size = sizeof(IMX25CCMState),
+    .instance_init = imx25_ccm_init,
+    .class_init    = imx25_ccm_class_init,
+};
+
+static void imx25_ccm_register_types(void)
+{
+    type_register_static(&imx25_ccm_info);
+}
+
+type_init(imx25_ccm_register_types)
diff --git a/hw/misc/imx31_ccm.c b/hw/misc/imx31_ccm.c
new file mode 100644
index 0000000000..b92d2e0392
--- /dev/null
+++ b/hw/misc/imx31_ccm.c
@@ -0,0 +1,392 @@
+/*
+ * IMX31 Clock Control Module
+ *
+ * Copyright (C) 2012 NICTA
+ * Updated by Jean-Christophe Dubois <jcd@tribudubois.net>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ * To get the timer frequencies right, we need to emulate at least part of
+ * the i.MX31 CCM.
+ */
+
+#include "hw/misc/imx31_ccm.h"
+
+#define CKIH_FREQ 26000000 /* 26MHz crystal input */
+
+#ifndef DEBUG_IMX31_CCM
+#define DEBUG_IMX31_CCM 0
+#endif
+
+#define DPRINTF(fmt, args...) \
+    do { \
+        if (DEBUG_IMX31_CCM) { \
+            fprintf(stderr, "[%s]%s: " fmt , TYPE_IMX31_CCM, \
+                                             __func__, ##args); \
+        } \
+    } while (0)
+
+static char const *imx31_ccm_reg_name(uint32_t reg)
+{
+    switch (reg) {
+    case 0:
+        return "CCMR";
+    case 1:
+        return "PDR0";
+    case 2:
+        return "PDR1";
+    case 3:
+        return "RCSR";
+    case 4:
+        return "MPCTL";
+    case 5:
+        return "UPCTL";
+    case 6:
+        return "SPCTL";
+    case 7:
+        return "COSR";
+    case 8:
+        return "CGR0";
+    case 9:
+        return "CGR1";
+    case 10:
+        return "CGR2";
+    case 11:
+        return "WIMR";
+    case 12:
+        return "LDC";
+    case 13:
+        return "DCVR0";
+    case 14:
+        return "DCVR1";
+    case 15:
+        return "DCVR2";
+    case 16:
+        return "DCVR3";
+    case 17:
+        return "LTR0";
+    case 18:
+        return "LTR1";
+    case 19:
+        return "LTR2";
+    case 20:
+        return "LTR3";
+    case 21:
+        return "LTBR0";
+    case 22:
+        return "LTBR1";
+    case 23:
+        return "PMCR0";
+    case 24:
+        return "PMCR1";
+    case 25:
+        return "PDR2";
+    default:
+        return "???";
+    }
+}
+
+static const VMStateDescription vmstate_imx31_ccm = {
+    .name = TYPE_IMX31_CCM,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(ccmr, IMX31CCMState),
+        VMSTATE_UINT32(pdr0, IMX31CCMState),
+        VMSTATE_UINT32(pdr1, IMX31CCMState),
+        VMSTATE_UINT32(mpctl, IMX31CCMState),
+        VMSTATE_UINT32(spctl, IMX31CCMState),
+        VMSTATE_UINT32_ARRAY(cgr, IMX31CCMState, 3),
+        VMSTATE_UINT32(pmcr0, IMX31CCMState),
+        VMSTATE_UINT32(pmcr1, IMX31CCMState),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static uint32_t imx31_ccm_get_pll_ref_clk(IMXCCMState *dev)
+{
+    uint32_t freq = 0;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    if ((s->ccmr & CCMR_PRCS) == 2) {
+        if (s->ccmr & CCMR_FPME) {
+            freq = CKIL_FREQ;
+            if (s->ccmr & CCMR_FPMF) {
+                freq *= 1024;
+            }
+        } 
+    } else {
+        freq = CKIH_FREQ;
+    }
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_mpll_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    freq = imx_ccm_calc_pll(s->mpctl, imx31_ccm_get_pll_ref_clk(dev));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_mcu_main_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    if ((s->ccmr & CCMR_MDS) || !(s->ccmr & CCMR_MPE)) {
+        freq = imx31_ccm_get_pll_ref_clk(dev);
+    } else {
+        freq = imx31_ccm_get_mpll_clk(dev);
+    }
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_mcu_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    freq = imx31_ccm_get_mcu_main_clk(dev) / (1 + EXTRACT(s->pdr0, MCU));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_hsp_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    freq = imx31_ccm_get_mcu_main_clk(dev) / (1 + EXTRACT(s->pdr0, HSP));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_hclk_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    freq = imx31_ccm_get_mcu_main_clk(dev) / (1 + EXTRACT(s->pdr0, MAX));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_ipg_clk(IMXCCMState *dev)
+{
+    uint32_t freq;
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    freq = imx31_ccm_get_hclk_clk(dev) / (1 + EXTRACT(s->pdr0, IPG));
+
+    DPRINTF("freq = %d\n", freq);
+
+    return freq;
+}
+
+static uint32_t imx31_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
+{
+    uint32_t freq = 0;
+
+    switch (clock) {
+    case NOCLK:
+        break;
+    case CLK_MCU:
+        freq = imx31_ccm_get_mcu_clk(dev);
+        break;
+    case CLK_HSP:
+        freq = imx31_ccm_get_hsp_clk(dev);
+        break;
+    case CLK_IPG:
+        freq = imx31_ccm_get_ipg_clk(dev);
+        break;
+    case CLK_32k:
+        freq = CKIL_FREQ;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: unsupported clock %d\n",
+                      TYPE_IMX31_CCM, __func__, clock);
+        break;
+    }
+
+    DPRINTF("Clock = %d) = %d\n", clock, freq);
+
+    return freq;
+}
+
+static void imx31_ccm_reset(DeviceState *dev)
+{
+    IMX31CCMState *s = IMX31_CCM(dev);
+
+    DPRINTF("()\n");
+
+    s->ccmr   = 0x074b0b7d;
+    s->pdr0   = 0xff870b48;
+    s->pdr1   = 0x49fcfe7f;
+    s->mpctl  = 0x04001800;
+    s->cgr[0] = s->cgr[1] = s->cgr[2] = 0xffffffff;
+    s->spctl  = 0x04043001;
+    s->pmcr0  = 0x80209828;
+    s->pmcr1  = 0x00aa0000;
+}
+
+static uint64_t imx31_ccm_read(void *opaque, hwaddr offset, unsigned size)
+{
+    uint32 value = 0;
+    IMX31CCMState *s = (IMX31CCMState *)opaque;
+
+    switch (offset >> 2) {
+    case 0: /* CCMR */
+        value = s->ccmr;
+        break;
+    case 1:
+        value = s->pdr0;
+        break;
+    case 2:
+        value = s->pdr1;
+        break;
+    case 4:
+        value = s->mpctl;
+        break;
+    case 6:
+        value = s->spctl;
+        break;
+    case 8:
+        value = s->cgr[0];
+        break;
+    case 9:
+        value = s->cgr[1];
+        break;
+    case 10:
+        value = s->cgr[2];
+        break;
+    case 18: /* LTR1 */
+        value = 0x00004040;
+        break;
+    case 23:
+        value = s->pmcr0;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+                      HWADDR_PRIx "\n", TYPE_IMX31_CCM, __func__, offset);
+        break;
+    }
+
+    DPRINTF("reg[%s] => 0x%" PRIx32 "\n", imx31_ccm_reg_name(offset >> 2),
+            value);
+
+    return (uint64_t)value;
+}
+
+static void imx31_ccm_write(void *opaque, hwaddr offset, uint64_t value,
+                            unsigned size)
+{
+    IMX31CCMState *s = (IMX31CCMState *)opaque;
+
+    DPRINTF("reg[%s] <= 0x%" PRIx32 "\n", imx31_ccm_reg_name(offset >> 2),
+            (uint32_t)value);
+
+    switch (offset >> 2) {
+    case 0:
+        s->ccmr = CCMR_FPMF | (value & 0x3b6fdfff);
+        break;
+    case 1:
+        s->pdr0 = value & 0xff9f3fff;
+        break;
+    case 2:
+        s->pdr1 = value;
+        break;
+    case 4:
+        s->mpctl = value & 0xbfff3fff;
+        break;
+    case 6:
+        s->spctl = value & 0xbfff3fff;
+        break;
+    case 8:
+        s->cgr[0] = value;
+        break;
+    case 9:
+        s->cgr[1] = value;
+        break;
+    case 10:
+        s->cgr[2] = value;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
+                      HWADDR_PRIx "\n", TYPE_IMX31_CCM, __func__, offset);
+        break;
+    }
+}
+
+static const struct MemoryRegionOps imx31_ccm_ops = {
+    .read = imx31_ccm_read,
+    .write = imx31_ccm_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid = {
+        /*
+         * Our device would not work correctly if the guest was doing
+         * unaligned access. This might not be a limitation on the real
+         * device but in practice there is no reason for a guest to access
+         * this device unaligned.
+         */
+        .min_access_size = 4,
+        .max_access_size = 4,
+        .unaligned = false,
+    },
+
+};
+
+static void imx31_ccm_init(Object *obj)
+{
+    DeviceState *dev = DEVICE(obj);
+    SysBusDevice *sd = SYS_BUS_DEVICE(obj);
+    IMX31CCMState *s = IMX31_CCM(obj);
+
+    memory_region_init_io(&s->iomem, OBJECT(dev), &imx31_ccm_ops, s,
+                          TYPE_IMX31_CCM, 0x1000);
+    sysbus_init_mmio(sd, &s->iomem);
+}
+
+static void imx31_ccm_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc  = DEVICE_CLASS(klass);
+    IMXCCMClass *ccm = IMX_CCM_CLASS(klass);
+
+    dc->reset = imx31_ccm_reset;
+    dc->vmsd  = &vmstate_imx31_ccm;
+    dc->desc  = "i.MX31 Clock Control Module";
+
+    ccm->get_clock_frequency = imx31_ccm_get_clock_frequency;
+}
+
+static const TypeInfo imx31_ccm_info = {
+    .name          = TYPE_IMX31_CCM,
+    .parent        = TYPE_IMX_CCM,
+    .instance_size = sizeof(IMX31CCMState),
+    .instance_init = imx31_ccm_init,
+    .class_init    = imx31_ccm_class_init,
+};
+
+static void imx31_ccm_register_types(void)
+{
+    type_register_static(&imx31_ccm_info);
+}
+
+type_init(imx31_ccm_register_types)
diff --git a/hw/misc/imx_ccm.c b/hw/misc/imx_ccm.c
index 4cc2bbc0ed..0c9740bd7a 100644
--- a/hw/misc/imx_ccm.c
+++ b/hw/misc/imx_ccm.c
@@ -7,15 +7,12 @@
  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  * See the COPYING file in the top-level directory.
  *
- * To get the timer frequencies right, we need to emulate at least part of
- * the CCM.
+ * This is an abstract base class used to get a common interface to
+ * retrieve the CCM frequencies from the various i.MX SOC.
  */
 
 #include "hw/misc/imx_ccm.h"
 
-#define CKIH_FREQ 26000000 /* 26MHz crystal input */
-#define CKIL_FREQ    32768 /* nominal 32khz clock */
-
 #ifndef DEBUG_IMX_CCM
 #define DEBUG_IMX_CCM 0
 #endif
@@ -28,51 +25,27 @@
         } \
     } while (0)
 
-static int imx_ccm_post_load(void *opaque, int version_id);
-
-static const VMStateDescription vmstate_imx_ccm = {
-    .name = TYPE_IMX_CCM,
-    .version_id = 1,
-    .minimum_version_id = 1,
-    .fields = (VMStateField[]) {
-        VMSTATE_UINT32(ccmr, IMXCCMState),
-        VMSTATE_UINT32(pdr0, IMXCCMState),
-        VMSTATE_UINT32(pdr1, IMXCCMState),
-        VMSTATE_UINT32(mpctl, IMXCCMState),
-        VMSTATE_UINT32(spctl, IMXCCMState),
-        VMSTATE_UINT32_ARRAY(cgr, IMXCCMState, 3),
-        VMSTATE_UINT32(pmcr0, IMXCCMState),
-        VMSTATE_UINT32(pmcr1, IMXCCMState),
-        VMSTATE_UINT32(pll_refclk_freq, IMXCCMState),
-        VMSTATE_END_OF_LIST()
-    },
-    .post_load = imx_ccm_post_load,
-};
 
-uint32_t imx_clock_frequency(DeviceState *dev, IMXClk clock)
+uint32_t imx_ccm_get_clock_frequency(IMXCCMState *dev, IMXClk clock)
 {
-    IMXCCMState *s = IMX_CCM(dev);
+    uint32_t freq = 0;
+    IMXCCMClass *klass = IMX_GET_CLASS(dev);
 
-    switch (clock) {
-    case NOCLK:
-        return 0;
-    case MCU:
-        return s->mcu_clk_freq;
-    case HSP:
-        return s->hsp_clk_freq;
-    case IPG:
-        return s->ipg_clk_freq;
-    case CLK_32k:
-        return CKIL_FREQ;
+    if (klass->get_clock_frequency) {
+        freq = klass->get_clock_frequency(dev, clock);
     }
-    return 0;
+
+    DPRINTF("(clock = %d) = %d\n", clock, freq);
+
+    return freq;
 }
 
 /*
  * Calculate PLL output frequency
  */
-static uint32_t calc_pll(uint32_t pllreg, uint32_t base_freq)
+uint32_t imx_ccm_calc_pll(uint32_t pllreg, uint32_t base_freq)
 {
+    int32_t freq;
     int32_t mfn = MFN(pllreg);  /* Numerator */
     uint32_t mfi = MFI(pllreg); /* Integer part */
     uint32_t mfd = 1 + MFD(pllreg); /* Denominator */
@@ -81,186 +54,26 @@ static uint32_t calc_pll(uint32_t pllreg, uint32_t base_freq)
     if (mfi < 5) {
         mfi = 5;
     }
+
     /* mfn is 10-bit signed twos-complement */
     mfn <<= 32 - 10;
     mfn >>= 32 - 10;
 
-    return ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) /
+    freq = ((2 * (base_freq >> 10) * (mfi * mfd + mfn)) /
             (mfd * pd)) << 10;
-}
-
-static void update_clocks(IMXCCMState *s)
-{
-    /*
-     * If we ever emulate more clocks, this should switch to a data-driven
-     * approach
-     */
-
-    if ((s->ccmr & CCMR_PRCS) == 2) {
-        s->pll_refclk_freq = CKIL_FREQ * 1024;
-    } else {
-        s->pll_refclk_freq = CKIH_FREQ;
-    }
-
-    /* ipg_clk_arm aka MCU clock */
-    if ((s->ccmr & CCMR_MDS) || !(s->ccmr & CCMR_MPE)) {
-        s->mcu_clk_freq = s->pll_refclk_freq;
-    } else {
-        s->mcu_clk_freq = calc_pll(s->mpctl, s->pll_refclk_freq);
-    }
-
-    /* High-speed clock */
-    s->hsp_clk_freq = s->mcu_clk_freq / (1 + EXTRACT(s->pdr0, HSP));
-    s->ipg_clk_freq = s->hsp_clk_freq / (1 + EXTRACT(s->pdr0, IPG));
-
-    DPRINTF("mcu %uMHz, HSP %uMHz, IPG %uHz\n",
-            s->mcu_clk_freq / 1000000,
-            s->hsp_clk_freq / 1000000,
-            s->ipg_clk_freq);
-}
-
-static void imx_ccm_reset(DeviceState *dev)
-{
-    IMXCCMState *s = IMX_CCM(dev);
-
-    s->ccmr = 0x074b0b7b;
-    s->pdr0 = 0xff870b48;
-    s->pdr1 = 0x49fcfe7f;
-    s->mpctl = PLL_PD(1) | PLL_MFD(0) | PLL_MFI(6) | PLL_MFN(0);
-    s->cgr[0] = s->cgr[1] = s->cgr[2] = 0xffffffff;
-    s->spctl = PLL_PD(1) | PLL_MFD(4) | PLL_MFI(0xc) | PLL_MFN(1);
-    s->pmcr0 = 0x80209828;
-
-    update_clocks(s);
-}
-
-static uint64_t imx_ccm_read(void *opaque, hwaddr offset,
-                                unsigned size)
-{
-    IMXCCMState *s = (IMXCCMState *)opaque;
 
-    DPRINTF("(offset=0x%" HWADDR_PRIx ")\n", offset);
-
-    switch (offset >> 2) {
-    case 0: /* CCMR */
-        DPRINTF(" ccmr = 0x%x\n", s->ccmr);
-        return s->ccmr;
-    case 1:
-        DPRINTF(" pdr0 = 0x%x\n", s->pdr0);
-        return s->pdr0;
-    case 2:
-        DPRINTF(" pdr1 = 0x%x\n", s->pdr1);
-        return s->pdr1;
-    case 4:
-        DPRINTF(" mpctl = 0x%x\n", s->mpctl);
-        return s->mpctl;
-    case 6:
-        DPRINTF(" spctl = 0x%x\n", s->spctl);
-        return s->spctl;
-    case 8:
-        DPRINTF(" cgr0 = 0x%x\n", s->cgr[0]);
-        return s->cgr[0];
-    case 9:
-        DPRINTF(" cgr1 = 0x%x\n", s->cgr[1]);
-        return s->cgr[1];
-    case 10:
-        DPRINTF(" cgr2 = 0x%x\n", s->cgr[2]);
-        return s->cgr[2];
-    case 18: /* LTR1 */
-        return 0x00004040;
-    case 23:
-        DPRINTF(" pcmr0 = 0x%x\n", s->pmcr0);
-        return s->pmcr0;
-    default:
-        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
-                      HWADDR_PRIx "\n", TYPE_IMX_CCM, __func__, offset);
-        return 0;
-    }
-}
-
-static void imx_ccm_write(void *opaque, hwaddr offset,
-                          uint64_t value, unsigned size)
-{
-    IMXCCMState *s = (IMXCCMState *)opaque;
-
-    DPRINTF("(offset=0x%" HWADDR_PRIx ", value = 0x%x)\n",
-            offset, (unsigned int)value);
-
-    switch (offset >> 2) {
-    case 0:
-        s->ccmr = CCMR_FPMF | (value & 0x3b6fdfff);
-        break;
-    case 1:
-        s->pdr0 = value & 0xff9f3fff;
-        break;
-    case 2:
-        s->pdr1 = value;
-        break;
-    case 4:
-        s->mpctl = value & 0xbfff3fff;
-        break;
-    case 6:
-        s->spctl = value & 0xbfff3fff;
-        break;
-    case 8:
-        s->cgr[0] = value;
-        return;
-    case 9:
-        s->cgr[1] = value;
-        return;
-    case 10:
-        s->cgr[2] = value;
-        return;
-
-    default:
-        qemu_log_mask(LOG_GUEST_ERROR, "[%s]%s: Bad register at offset 0x%"
-                      HWADDR_PRIx "\n", TYPE_IMX_CCM, __func__, offset);
-        return;
-    }
-    update_clocks(s);
-}
-
-static const struct MemoryRegionOps imx_ccm_ops = {
-    .read = imx_ccm_read,
-    .write = imx_ccm_write,
-    .endianness = DEVICE_NATIVE_ENDIAN,
-};
-
-static int imx_ccm_init(SysBusDevice *dev)
-{
-    IMXCCMState *s = IMX_CCM(dev);
-
-    memory_region_init_io(&s->iomem, OBJECT(dev), &imx_ccm_ops, s,
-                          TYPE_IMX_CCM, 0x1000);
-    sysbus_init_mmio(dev, &s->iomem);
-
-    return 0;
-}
-
-static int imx_ccm_post_load(void *opaque, int version_id)
-{
-    IMXCCMState *s = (IMXCCMState *)opaque;
-
-    update_clocks(s);
-    return 0;
-}
-
-static void imx_ccm_class_init(ObjectClass *klass, void *data)
-{
-    DeviceClass *dc = DEVICE_CLASS(klass);
-    SysBusDeviceClass *sbc = SYS_BUS_DEVICE_CLASS(klass);
+    DPRINTF("(pllreg = 0x%08x, base_freq = %d) = %d\n", pllreg, base_freq,
+            freq);
 
-    sbc->init = imx_ccm_init;
-    dc->reset = imx_ccm_reset;
-    dc->vmsd = &vmstate_imx_ccm;
-    dc->desc = "i.MX Clock Control Module";
+    return freq;
 }
 
 static const TypeInfo imx_ccm_info = {
-    .name = TYPE_IMX_CCM,
-    .parent = TYPE_SYS_BUS_DEVICE,
+    .name          = TYPE_IMX_CCM,
+    .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(IMXCCMState),
-    .class_init = imx_ccm_class_init,
+    .class_size    = sizeof(IMXCCMClass),
+    .abstract      = true,
 };
 
 static void imx_ccm_register_types(void)