/* * ASPEED Watchdog Controller * * Copyright (C) 2016-2017 IBM Corp. * * This code is licensed under the GPL version 2 or later. See the * COPYING file in the top-level directory. */ #include "qemu/osdep.h" #include "qapi/error.h" #include "qemu/log.h" #include "qemu/timer.h" #include "sysemu/watchdog.h" #include "hw/misc/aspeed_scu.h" #include "hw/sysbus.h" #include "hw/watchdog/wdt_aspeed.h" #define WDT_STATUS (0x00 / 4) #define WDT_RELOAD_VALUE (0x04 / 4) #define WDT_RESTART (0x08 / 4) #define WDT_CTRL (0x0C / 4) #define WDT_CTRL_RESET_MODE_SOC (0x00 << 5) #define WDT_CTRL_RESET_MODE_FULL_CHIP (0x01 << 5) #define WDT_CTRL_1MHZ_CLK BIT(4) #define WDT_CTRL_WDT_EXT BIT(3) #define WDT_CTRL_WDT_INTR BIT(2) #define WDT_CTRL_RESET_SYSTEM BIT(1) #define WDT_CTRL_ENABLE BIT(0) #define WDT_RESET_WIDTH (0x18 / 4) #define WDT_RESET_WIDTH_ACTIVE_HIGH BIT(31) #define WDT_POLARITY_MASK (0xFF << 24) #define WDT_ACTIVE_HIGH_MAGIC (0xA5 << 24) #define WDT_ACTIVE_LOW_MAGIC (0x5A << 24) #define WDT_RESET_WIDTH_PUSH_PULL BIT(30) #define WDT_DRIVE_TYPE_MASK (0xFF << 24) #define WDT_PUSH_PULL_MAGIC (0xA8 << 24) #define WDT_OPEN_DRAIN_MAGIC (0x8A << 24) #define WDT_TIMEOUT_STATUS (0x10 / 4) #define WDT_TIMEOUT_CLEAR (0x14 / 4) #define WDT_RESTART_MAGIC 0x4755 static bool aspeed_wdt_is_enabled(const AspeedWDTState *s) { return s->regs[WDT_CTRL] & WDT_CTRL_ENABLE; } static bool is_ast2500(const AspeedWDTState *s) { switch (s->silicon_rev) { case AST2500_A0_SILICON_REV: case AST2500_A1_SILICON_REV: return true; case AST2400_A0_SILICON_REV: case AST2400_A1_SILICON_REV: default: break; } return false; } static uint64_t aspeed_wdt_read(void *opaque, hwaddr offset, unsigned size) { AspeedWDTState *s = ASPEED_WDT(opaque); offset >>= 2; switch (offset) { case WDT_STATUS: return s->regs[WDT_STATUS]; case WDT_RELOAD_VALUE: return s->regs[WDT_RELOAD_VALUE]; case WDT_RESTART: qemu_log_mask(LOG_GUEST_ERROR, "%s: read from write-only reg at offset 0x%" HWADDR_PRIx "\n", __func__, offset); return 0; case WDT_CTRL: return s->regs[WDT_CTRL]; case WDT_RESET_WIDTH: return s->regs[WDT_RESET_WIDTH]; case WDT_TIMEOUT_STATUS: case WDT_TIMEOUT_CLEAR: qemu_log_mask(LOG_UNIMP, "%s: uninmplemented read at offset 0x%" HWADDR_PRIx "\n", __func__, offset); return 0; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n", __func__, offset); return 0; } } static void aspeed_wdt_reload(AspeedWDTState *s, bool pclk) { uint64_t reload; if (pclk) { reload = muldiv64(s->regs[WDT_RELOAD_VALUE], NANOSECONDS_PER_SECOND, s->pclk_freq); } else { reload = s->regs[WDT_RELOAD_VALUE] * 1000ULL; } if (aspeed_wdt_is_enabled(s)) { timer_mod(s->timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + reload); } } static void aspeed_wdt_write(void *opaque, hwaddr offset, uint64_t data, unsigned size) { AspeedWDTState *s = ASPEED_WDT(opaque); bool enable = data & WDT_CTRL_ENABLE; offset >>= 2; switch (offset) { case WDT_STATUS: qemu_log_mask(LOG_GUEST_ERROR, "%s: write to read-only reg at offset 0x%" HWADDR_PRIx "\n", __func__, offset); break; case WDT_RELOAD_VALUE: s->regs[WDT_RELOAD_VALUE] = data; break; case WDT_RESTART: if ((data & 0xFFFF) == WDT_RESTART_MAGIC) { s->regs[WDT_STATUS] = s->regs[WDT_RELOAD_VALUE]; aspeed_wdt_reload(s, !(data & WDT_CTRL_1MHZ_CLK)); } break; case WDT_CTRL: if (enable && !aspeed_wdt_is_enabled(s)) { s->regs[WDT_CTRL] = data; aspeed_wdt_reload(s, !(data & WDT_CTRL_1MHZ_CLK)); } else if (!enable && aspeed_wdt_is_enabled(s)) { s->regs[WDT_CTRL] = data; timer_del(s->timer); } break; case WDT_RESET_WIDTH: { uint32_t property = data & WDT_POLARITY_MASK; if (property && is_ast2500(s)) { if (property == WDT_ACTIVE_HIGH_MAGIC) { s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_ACTIVE_HIGH; } else if (property == WDT_ACTIVE_LOW_MAGIC) { s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_ACTIVE_HIGH; } else if (property == WDT_PUSH_PULL_MAGIC) { s->regs[WDT_RESET_WIDTH] |= WDT_RESET_WIDTH_PUSH_PULL; } else if (property == WDT_OPEN_DRAIN_MAGIC) { s->regs[WDT_RESET_WIDTH] &= ~WDT_RESET_WIDTH_PUSH_PULL; } } s->regs[WDT_RESET_WIDTH] &= ~s->ext_pulse_width_mask; s->regs[WDT_RESET_WIDTH] |= data & s->ext_pulse_width_mask; break; } case WDT_TIMEOUT_STATUS: case WDT_TIMEOUT_CLEAR: qemu_log_mask(LOG_UNIMP, "%s: uninmplemented write at offset 0x%" HWADDR_PRIx "\n", __func__, offset); break; default: qemu_log_mask(LOG_GUEST_ERROR, "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n", __func__, offset); } return; } static WatchdogTimerModel model = { .wdt_name = TYPE_ASPEED_WDT, .wdt_description = "Aspeed watchdog device", }; static const VMStateDescription vmstate_aspeed_wdt = { .name = "vmstate_aspeed_wdt", .version_id = 0, .minimum_version_id = 0, .fields = (VMStateField[]) { VMSTATE_TIMER_PTR(timer, AspeedWDTState), VMSTATE_UINT32_ARRAY(regs, AspeedWDTState, ASPEED_WDT_REGS_MAX), VMSTATE_END_OF_LIST() } }; static const MemoryRegionOps aspeed_wdt_ops = { .read = aspeed_wdt_read, .write = aspeed_wdt_write, .endianness = DEVICE_LITTLE_ENDIAN, .valid.min_access_size = 4, .valid.max_access_size = 4, .valid.unaligned = false, }; static void aspeed_wdt_reset(DeviceState *dev) { AspeedWDTState *s = ASPEED_WDT(dev); s->regs[WDT_STATUS] = 0x3EF1480; s->regs[WDT_RELOAD_VALUE] = 0x03EF1480; s->regs[WDT_RESTART] = 0; s->regs[WDT_CTRL] = 0; s->regs[WDT_RESET_WIDTH] = 0xFF; timer_del(s->timer); } static void aspeed_wdt_timer_expired(void *dev) { AspeedWDTState *s = ASPEED_WDT(dev); qemu_log_mask(CPU_LOG_RESET, "Watchdog timer expired.\n"); watchdog_perform_action(); timer_del(s->timer); } #define PCLK_HZ 24000000 static void aspeed_wdt_realize(DeviceState *dev, Error **errp) { SysBusDevice *sbd = SYS_BUS_DEVICE(dev); AspeedWDTState *s = ASPEED_WDT(dev); if (!is_supported_silicon_rev(s->silicon_rev)) { error_setg(errp, "Unknown silicon revision: 0x%" PRIx32, s->silicon_rev); return; } switch (s->silicon_rev) { case AST2400_A0_SILICON_REV: case AST2400_A1_SILICON_REV: s->ext_pulse_width_mask = 0xff; break; case AST2500_A0_SILICON_REV: case AST2500_A1_SILICON_REV: s->ext_pulse_width_mask = 0xfffff; break; default: g_assert_not_reached(); } s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, aspeed_wdt_timer_expired, dev); /* FIXME: This setting should be derived from the SCU hw strapping * register SCU70 */ s->pclk_freq = PCLK_HZ; memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_wdt_ops, s, TYPE_ASPEED_WDT, ASPEED_WDT_REGS_MAX * 4); sysbus_init_mmio(sbd, &s->iomem); } static Property aspeed_wdt_properties[] = { DEFINE_PROP_UINT32("silicon-rev", AspeedWDTState, silicon_rev, 0), DEFINE_PROP_END_OF_LIST(), }; static void aspeed_wdt_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); dc->realize = aspeed_wdt_realize; dc->reset = aspeed_wdt_reset; set_bit(DEVICE_CATEGORY_MISC, dc->categories); dc->vmsd = &vmstate_aspeed_wdt; dc->props = aspeed_wdt_properties; } static const TypeInfo aspeed_wdt_info = { .parent = TYPE_SYS_BUS_DEVICE, .name = TYPE_ASPEED_WDT, .instance_size = sizeof(AspeedWDTState), .class_init = aspeed_wdt_class_init, }; static void wdt_aspeed_register_types(void) { watchdog_add_model(&model); type_register_static(&aspeed_wdt_info); } type_init(wdt_aspeed_register_types)