diff options
Diffstat (limited to 'hw/gpio/npcm7xx_gpio.c')
| -rw-r--r-- | hw/gpio/npcm7xx_gpio.c | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/hw/gpio/npcm7xx_gpio.c b/hw/gpio/npcm7xx_gpio.c new file mode 100644 index 0000000000..3376901ab1 --- /dev/null +++ b/hw/gpio/npcm7xx_gpio.c @@ -0,0 +1,424 @@ +/* + * Nuvoton NPCM7xx General Purpose Input / Output (GPIO) + * + * 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 + * version 2 as published by the Free Software Foundation. + * + * 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/gpio/npcm7xx_gpio.h" +#include "hw/irq.h" +#include "hw/qdev-properties.h" +#include "migration/vmstate.h" +#include "qapi/error.h" +#include "qemu/log.h" +#include "qemu/module.h" +#include "qemu/units.h" +#include "trace.h" + +/* 32-bit register indices. */ +enum NPCM7xxGPIORegister { + NPCM7XX_GPIO_TLOCK1, + NPCM7XX_GPIO_DIN, + NPCM7XX_GPIO_POL, + NPCM7XX_GPIO_DOUT, + NPCM7XX_GPIO_OE, + NPCM7XX_GPIO_OTYP, + NPCM7XX_GPIO_MP, + NPCM7XX_GPIO_PU, + NPCM7XX_GPIO_PD, + NPCM7XX_GPIO_DBNC, + NPCM7XX_GPIO_EVTYP, + NPCM7XX_GPIO_EVBE, + NPCM7XX_GPIO_OBL0, + NPCM7XX_GPIO_OBL1, + NPCM7XX_GPIO_OBL2, + NPCM7XX_GPIO_OBL3, + NPCM7XX_GPIO_EVEN, + NPCM7XX_GPIO_EVENS, + NPCM7XX_GPIO_EVENC, + NPCM7XX_GPIO_EVST, + NPCM7XX_GPIO_SPLCK, + NPCM7XX_GPIO_MPLCK, + NPCM7XX_GPIO_IEM, + NPCM7XX_GPIO_OSRC, + NPCM7XX_GPIO_ODSC, + NPCM7XX_GPIO_DOS = 0x68 / sizeof(uint32_t), + NPCM7XX_GPIO_DOC, + NPCM7XX_GPIO_OES, + NPCM7XX_GPIO_OEC, + NPCM7XX_GPIO_TLOCK2 = 0x7c / sizeof(uint32_t), + NPCM7XX_GPIO_REGS_END, +}; + +#define NPCM7XX_GPIO_REGS_SIZE (4 * KiB) + +#define NPCM7XX_GPIO_LOCK_MAGIC1 (0xc0defa73) +#define NPCM7XX_GPIO_LOCK_MAGIC2 (0xc0de1248) + +static void npcm7xx_gpio_update_events(NPCM7xxGPIOState *s, uint32_t din_diff) +{ + uint32_t din_new = s->regs[NPCM7XX_GPIO_DIN]; + + /* Trigger on high level */ + s->regs[NPCM7XX_GPIO_EVST] |= din_new & ~s->regs[NPCM7XX_GPIO_EVTYP]; + /* Trigger on both edges */ + s->regs[NPCM7XX_GPIO_EVST] |= (din_diff & s->regs[NPCM7XX_GPIO_EVTYP] + & s->regs[NPCM7XX_GPIO_EVBE]); + /* Trigger on rising edge */ + s->regs[NPCM7XX_GPIO_EVST] |= (din_diff & din_new + & s->regs[NPCM7XX_GPIO_EVTYP]); + + trace_npcm7xx_gpio_update_events(DEVICE(s)->canonical_path, + s->regs[NPCM7XX_GPIO_EVST], + s->regs[NPCM7XX_GPIO_EVEN]); + qemu_set_irq(s->irq, !!(s->regs[NPCM7XX_GPIO_EVST] + & s->regs[NPCM7XX_GPIO_EVEN])); +} + +static void npcm7xx_gpio_update_pins(NPCM7xxGPIOState *s, uint32_t diff) +{ + uint32_t drive_en; + uint32_t drive_lvl; + uint32_t not_driven; + uint32_t undefined; + uint32_t pin_diff; + uint32_t din_old; + + /* Calculate level of each pin driven by GPIO controller. */ + drive_lvl = s->regs[NPCM7XX_GPIO_DOUT] ^ s->regs[NPCM7XX_GPIO_POL]; + /* If OTYP=1, only drive low (open drain) */ + drive_en = s->regs[NPCM7XX_GPIO_OE] & ~(s->regs[NPCM7XX_GPIO_OTYP] + & drive_lvl); + /* + * If a pin is driven to opposite levels by the GPIO controller and the + * external driver, the result is undefined. + */ + undefined = drive_en & s->ext_driven & (drive_lvl ^ s->ext_level); + if (undefined) { + qemu_log_mask(LOG_GUEST_ERROR, + "%s: pins have multiple drivers: 0x%" PRIx32 "\n", + DEVICE(s)->canonical_path, undefined); + } + + not_driven = ~(drive_en | s->ext_driven); + pin_diff = s->pin_level; + + /* Set pins to externally driven level. */ + s->pin_level = s->ext_level & s->ext_driven; + /* Set internally driven pins, ignoring any conflicts. */ + s->pin_level |= drive_lvl & drive_en; + /* Pull up undriven pins with internal pull-up enabled. */ + s->pin_level |= not_driven & s->regs[NPCM7XX_GPIO_PU]; + /* Pins not driven, pulled up or pulled down are undefined */ + undefined |= not_driven & ~(s->regs[NPCM7XX_GPIO_PU] + | s->regs[NPCM7XX_GPIO_PD]); + + /* If any pins changed state, update the outgoing GPIOs. */ + pin_diff ^= s->pin_level; + pin_diff |= undefined & diff; + if (pin_diff) { + int i; + + for (i = 0; i < NPCM7XX_GPIO_NR_PINS; i++) { + uint32_t mask = BIT(i); + if (pin_diff & mask) { + int level = (undefined & mask) ? -1 : !!(s->pin_level & mask); + trace_npcm7xx_gpio_set_output(DEVICE(s)->canonical_path, + i, level); + qemu_set_irq(s->output[i], level); + } + } + } + + /* Calculate new value of DIN after masking and polarity setting. */ + din_old = s->regs[NPCM7XX_GPIO_DIN]; + s->regs[NPCM7XX_GPIO_DIN] = ((s->pin_level & s->regs[NPCM7XX_GPIO_IEM]) + ^ s->regs[NPCM7XX_GPIO_POL]); + + /* See if any new events triggered because of all this. */ + npcm7xx_gpio_update_events(s, din_old ^ s->regs[NPCM7XX_GPIO_DIN]); +} + +static bool npcm7xx_gpio_is_locked(NPCM7xxGPIOState *s) +{ + return s->regs[NPCM7XX_GPIO_TLOCK1] == 1; +} + +static uint64_t npcm7xx_gpio_regs_read(void *opaque, hwaddr addr, + unsigned int size) +{ + hwaddr reg = addr / sizeof(uint32_t); + NPCM7xxGPIOState *s = opaque; + uint64_t value = 0; + + switch (reg) { + case NPCM7XX_GPIO_TLOCK1 ... NPCM7XX_GPIO_EVEN: + case NPCM7XX_GPIO_EVST ... NPCM7XX_GPIO_ODSC: + value = s->regs[reg]; + break; + + case NPCM7XX_GPIO_EVENS ... NPCM7XX_GPIO_EVENC: + case NPCM7XX_GPIO_DOS ... NPCM7XX_GPIO_TLOCK2: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: read from write-only register 0x%" HWADDR_PRIx "\n", + DEVICE(s)->canonical_path, addr); + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: read from invalid offset 0x%" HWADDR_PRIx "\n", + DEVICE(s)->canonical_path, addr); + break; + } + + trace_npcm7xx_gpio_read(DEVICE(s)->canonical_path, addr, value); + + return value; +} + +static void npcm7xx_gpio_regs_write(void *opaque, hwaddr addr, uint64_t v, + unsigned int size) +{ + hwaddr reg = addr / sizeof(uint32_t); + NPCM7xxGPIOState *s = opaque; + uint32_t value = v; + uint32_t diff; + + trace_npcm7xx_gpio_write(DEVICE(s)->canonical_path, addr, v); + + if (npcm7xx_gpio_is_locked(s)) { + switch (reg) { + case NPCM7XX_GPIO_TLOCK1: + if (s->regs[NPCM7XX_GPIO_TLOCK2] == NPCM7XX_GPIO_LOCK_MAGIC2 && + value == NPCM7XX_GPIO_LOCK_MAGIC1) { + s->regs[NPCM7XX_GPIO_TLOCK1] = 0; + s->regs[NPCM7XX_GPIO_TLOCK2] = 0; + } + break; + + case NPCM7XX_GPIO_TLOCK2: + s->regs[reg] = value; + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to locked register @ 0x%" HWADDR_PRIx "\n", + DEVICE(s)->canonical_path, addr); + break; + } + + return; + } + + diff = s->regs[reg] ^ value; + + switch (reg) { + case NPCM7XX_GPIO_TLOCK1: + case NPCM7XX_GPIO_TLOCK2: + s->regs[NPCM7XX_GPIO_TLOCK1] = 1; + s->regs[NPCM7XX_GPIO_TLOCK2] = 0; + break; + + case NPCM7XX_GPIO_DIN: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to read-only register @ 0x%" HWADDR_PRIx "\n", + DEVICE(s)->canonical_path, addr); + break; + + case NPCM7XX_GPIO_POL: + case NPCM7XX_GPIO_DOUT: + case NPCM7XX_GPIO_OE: + case NPCM7XX_GPIO_OTYP: + case NPCM7XX_GPIO_PU: + case NPCM7XX_GPIO_PD: + case NPCM7XX_GPIO_IEM: + s->regs[reg] = value; + npcm7xx_gpio_update_pins(s, diff); + break; + + case NPCM7XX_GPIO_DOS: + s->regs[NPCM7XX_GPIO_DOUT] |= value; + npcm7xx_gpio_update_pins(s, value); + break; + case NPCM7XX_GPIO_DOC: + s->regs[NPCM7XX_GPIO_DOUT] &= ~value; + npcm7xx_gpio_update_pins(s, value); + break; + case NPCM7XX_GPIO_OES: + s->regs[NPCM7XX_GPIO_OE] |= value; + npcm7xx_gpio_update_pins(s, value); + break; + case NPCM7XX_GPIO_OEC: + s->regs[NPCM7XX_GPIO_OE] &= ~value; + npcm7xx_gpio_update_pins(s, value); + break; + + case NPCM7XX_GPIO_EVTYP: + case NPCM7XX_GPIO_EVBE: + case NPCM7XX_GPIO_EVEN: + s->regs[reg] = value; + npcm7xx_gpio_update_events(s, 0); + break; + + case NPCM7XX_GPIO_EVENS: + s->regs[NPCM7XX_GPIO_EVEN] |= value; + npcm7xx_gpio_update_events(s, 0); + break; + case NPCM7XX_GPIO_EVENC: + s->regs[NPCM7XX_GPIO_EVEN] &= ~value; + npcm7xx_gpio_update_events(s, 0); + break; + + case NPCM7XX_GPIO_EVST: + s->regs[reg] &= ~value; + npcm7xx_gpio_update_events(s, 0); + break; + + case NPCM7XX_GPIO_MP: + case NPCM7XX_GPIO_DBNC: + case NPCM7XX_GPIO_OSRC: + case NPCM7XX_GPIO_ODSC: + /* Nothing to do; just store the value. */ + s->regs[reg] = value; + break; + + case NPCM7XX_GPIO_OBL0: + case NPCM7XX_GPIO_OBL1: + case NPCM7XX_GPIO_OBL2: + case NPCM7XX_GPIO_OBL3: + s->regs[reg] = value; + qemu_log_mask(LOG_UNIMP, "%s: Blinking is not implemented\n", + __func__); + break; + + case NPCM7XX_GPIO_SPLCK: + case NPCM7XX_GPIO_MPLCK: + qemu_log_mask(LOG_UNIMP, "%s: Per-pin lock is not implemented\n", + __func__); + break; + + default: + qemu_log_mask(LOG_GUEST_ERROR, + "%s: write to invalid offset 0x%" HWADDR_PRIx "\n", + DEVICE(s)->canonical_path, addr); + break; + } +} + +static const MemoryRegionOps npcm7xx_gpio_regs_ops = { + .read = npcm7xx_gpio_regs_read, + .write = npcm7xx_gpio_regs_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + .unaligned = false, + }, +}; + +static void npcm7xx_gpio_set_input(void *opaque, int line, int level) +{ + NPCM7xxGPIOState *s = opaque; + + trace_npcm7xx_gpio_set_input(DEVICE(s)->canonical_path, line, level); + + g_assert(line >= 0 && line < NPCM7XX_GPIO_NR_PINS); + + s->ext_driven = deposit32(s->ext_driven, line, 1, level >= 0); + s->ext_level = deposit32(s->ext_level, line, 1, level > 0); + + npcm7xx_gpio_update_pins(s, BIT(line)); +} + +static void npcm7xx_gpio_enter_reset(Object *obj, ResetType type) +{ + NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); + + memset(s->regs, 0, sizeof(s->regs)); + + s->regs[NPCM7XX_GPIO_PU] = s->reset_pu; + s->regs[NPCM7XX_GPIO_PD] = s->reset_pd; + s->regs[NPCM7XX_GPIO_OSRC] = s->reset_osrc; + s->regs[NPCM7XX_GPIO_ODSC] = s->reset_odsc; +} + +static void npcm7xx_gpio_hold_reset(Object *obj) +{ + NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); + + npcm7xx_gpio_update_pins(s, -1); +} + +static void npcm7xx_gpio_init(Object *obj) +{ + NPCM7xxGPIOState *s = NPCM7XX_GPIO(obj); + DeviceState *dev = DEVICE(obj); + + memory_region_init_io(&s->mmio, obj, &npcm7xx_gpio_regs_ops, s, + "regs", NPCM7XX_GPIO_REGS_SIZE); + sysbus_init_mmio(SYS_BUS_DEVICE(obj), &s->mmio); + sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->irq); + + qdev_init_gpio_in(dev, npcm7xx_gpio_set_input, NPCM7XX_GPIO_NR_PINS); + qdev_init_gpio_out(dev, s->output, NPCM7XX_GPIO_NR_PINS); +} + +static const VMStateDescription vmstate_npcm7xx_gpio = { + .name = "npcm7xx-gpio", + .version_id = 0, + .minimum_version_id = 0, + .fields = (VMStateField[]) { + VMSTATE_UINT32(pin_level, NPCM7xxGPIOState), + VMSTATE_UINT32(ext_level, NPCM7xxGPIOState), + VMSTATE_UINT32(ext_driven, NPCM7xxGPIOState), + VMSTATE_UINT32_ARRAY(regs, NPCM7xxGPIOState, NPCM7XX_GPIO_NR_REGS), + VMSTATE_END_OF_LIST(), + }, +}; + +static Property npcm7xx_gpio_properties[] = { + /* Bit n set => pin n has pullup enabled by default. */ + DEFINE_PROP_UINT32("reset-pullup", NPCM7xxGPIOState, reset_pu, 0), + /* Bit n set => pin n has pulldown enabled by default. */ + DEFINE_PROP_UINT32("reset-pulldown", NPCM7xxGPIOState, reset_pd, 0), + /* Bit n set => pin n has high slew rate by default. */ + DEFINE_PROP_UINT32("reset-osrc", NPCM7xxGPIOState, reset_osrc, 0), + /* Bit n set => pin n has high drive strength by default. */ + DEFINE_PROP_UINT32("reset-odsc", NPCM7xxGPIOState, reset_odsc, 0), + DEFINE_PROP_END_OF_LIST(), +}; + +static void npcm7xx_gpio_class_init(ObjectClass *klass, void *data) +{ + ResettableClass *reset = RESETTABLE_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + QEMU_BUILD_BUG_ON(NPCM7XX_GPIO_REGS_END > NPCM7XX_GPIO_NR_REGS); + + dc->desc = "NPCM7xx GPIO Controller"; + dc->vmsd = &vmstate_npcm7xx_gpio; + reset->phases.enter = npcm7xx_gpio_enter_reset; + reset->phases.hold = npcm7xx_gpio_hold_reset; + device_class_set_props(dc, npcm7xx_gpio_properties); +} + +static const TypeInfo npcm7xx_gpio_types[] = { + { + .name = TYPE_NPCM7XX_GPIO, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(NPCM7xxGPIOState), + .class_init = npcm7xx_gpio_class_init, + .instance_init = npcm7xx_gpio_init, + }, +}; +DEFINE_TYPES(npcm7xx_gpio_types); |