From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40372) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cfq0n-0006do-OB for qemu-devel@nongnu.org; Mon, 20 Feb 2017 10:36:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cfq0l-0003RK-8s for qemu-devel@nongnu.org; Mon, 20 Feb 2017 10:36:25 -0500 From: Peter Maydell Date: Mon, 20 Feb 2017 15:36:03 +0000 Message-Id: <1487604965-23220-10-git-send-email-peter.maydell@linaro.org> In-Reply-To: <1487604965-23220-1-git-send-email-peter.maydell@linaro.org> References: <1487604965-23220-1-git-send-email-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH 09/11] armv7m: Split systick out from NVIC List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, qemu-devel@nongnu.org Cc: patches@linaro.org, =?UTF-8?q?Alex=20Benn=C3=A9e?= , Alistair Francis , Michael Davidsaver The SysTick timer isn't really part of the NVIC proper; we just modelled it that way back when we couldn't easily have devices that only occupied a small chunk of a memory region. Split it out into its own device. Signed-off-by: Peter Maydell --- hw/timer/Makefile.objs | 1 + include/hw/arm/armv7m_nvic.h | 10 +- include/hw/timer/armv7m_systick.h | 34 ++++++ hw/intc/armv7m_nvic.c | 160 ++++++------------------- hw/timer/armv7m_systick.c | 239 ++++++++++++++++++++++++++++++++++++++ hw/timer/trace-events | 6 + 6 files changed, 317 insertions(+), 133 deletions(-) create mode 100644 include/hw/timer/armv7m_systick.h create mode 100644 hw/timer/armv7m_systick.c diff --git a/hw/timer/Makefile.objs b/hw/timer/Makefile.objs index fc99668..dd6f27e 100644 --- a/hw/timer/Makefile.objs +++ b/hw/timer/Makefile.objs @@ -1,5 +1,6 @@ common-obj-$(CONFIG_ARM_TIMER) += arm_timer.o common-obj-$(CONFIG_ARM_MPTIMER) += arm_mptimer.o +common-obj-$(CONFIG_ARM_V7M) += armv7m_systick.o common-obj-$(CONFIG_A9_GTIMER) += a9gtimer.o common-obj-$(CONFIG_CADENCE) += cadence_ttc.o common-obj-$(CONFIG_DS1338) += ds1338.o diff --git a/include/hw/arm/armv7m_nvic.h b/include/hw/arm/armv7m_nvic.h index 39b94ee..1d145fb 100644 --- a/include/hw/arm/armv7m_nvic.h +++ b/include/hw/arm/armv7m_nvic.h @@ -12,6 +12,7 @@ #include "target/arm/cpu.h" #include "hw/sysbus.h" +#include "hw/timer/armv7m_systick.h" #define TYPE_NVIC "armv7m_nvic" @@ -48,19 +49,14 @@ typedef struct NVICState { unsigned int vectpending; /* highest prio pending enabled exception */ int exception_prio; /* group prio of the highest prio active exception */ - struct { - uint32_t control; - uint32_t reload; - int64_t tick; - QEMUTimer *timer; - } systick; - MemoryRegion sysregmem; MemoryRegion container; uint32_t num_irq; qemu_irq excpout; qemu_irq sysresetreq; + + SysTickState systick; } NVICState; #endif diff --git a/include/hw/timer/armv7m_systick.h b/include/hw/timer/armv7m_systick.h new file mode 100644 index 0000000..cca04de --- /dev/null +++ b/include/hw/timer/armv7m_systick.h @@ -0,0 +1,34 @@ +/* + * ARMv7M SysTick timer + * + * Copyright (c) 2006-2007 CodeSourcery. + * Written by Paul Brook + * Copyright (c) 2017 Linaro Ltd + * Written by Peter Maydell + * + * This code is licensed under the GPL (version 2 or later). + */ + +#ifndef HW_TIMER_ARMV7M_SYSTICK_H +#define HW_TIMER_ARMV7M_SYSTICK_H + +#include "hw/sysbus.h" + +#define TYPE_SYSTICK "armv7m_systick" + +#define SYSTICK(obj) OBJECT_CHECK(SysTickState, (obj), TYPE_SYSTICK) + +typedef struct SysTickState { + /*< private >*/ + SysBusDevice parent_obj; + /*< public >*/ + + uint32_t control; + uint32_t reload; + int64_t tick; + QEMUTimer *timer; + MemoryRegion iomem; + qemu_irq irq; +} SysTickState; + +#endif diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c index c814e16..32ffa0b 100644 --- a/hw/intc/armv7m_nvic.c +++ b/hw/intc/armv7m_nvic.c @@ -58,65 +58,6 @@ static const uint8_t nvic_id[] = { 0x00, 0xb0, 0x1b, 0x00, 0x0d, 0xe0, 0x05, 0xb1 }; -/* qemu timers run at 1GHz. We want something closer to 1MHz. */ -#define SYSTICK_SCALE 1000ULL - -#define SYSTICK_ENABLE (1 << 0) -#define SYSTICK_TICKINT (1 << 1) -#define SYSTICK_CLKSOURCE (1 << 2) -#define SYSTICK_COUNTFLAG (1 << 16) - -int system_clock_scale; - -/* Conversion factor from qemu timer to SysTick frequencies. */ -static inline int64_t systick_scale(NVICState *s) -{ - if (s->systick.control & SYSTICK_CLKSOURCE) - return system_clock_scale; - else - return 1000; -} - -static void systick_reload(NVICState *s, int reset) -{ - /* The Cortex-M3 Devices Generic User Guide says that "When the - * ENABLE bit is set to 1, the counter loads the RELOAD value from the - * SYST RVR register and then counts down". So, we need to check the - * ENABLE bit before reloading the value. - */ - if ((s->systick.control & SYSTICK_ENABLE) == 0) { - return; - } - - if (reset) - s->systick.tick = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); - s->systick.tick += (s->systick.reload + 1) * systick_scale(s); - timer_mod(s->systick.timer, s->systick.tick); -} - -static void systick_timer_tick(void * opaque) -{ - NVICState *s = (NVICState *)opaque; - s->systick.control |= SYSTICK_COUNTFLAG; - if (s->systick.control & SYSTICK_TICKINT) { - /* Trigger the interrupt. */ - armv7m_nvic_set_pending(s, ARMV7M_EXCP_SYSTICK); - } - if (s->systick.reload == 0) { - s->systick.control &= ~SYSTICK_ENABLE; - } else { - systick_reload(s, 0); - } -} - -static void systick_reset(NVICState *s) -{ - s->systick.control = 0; - s->systick.reload = 0; - s->systick.tick = 0; - timer_del(s->systick.timer); -} - static int nvic_pending_prio(NVICState *s) { /* return the priority of the current pending interrupt, @@ -462,30 +403,6 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset) switch (offset) { case 4: /* Interrupt Control Type. */ return ((s->num_irq - NVIC_FIRST_IRQ) / 32) - 1; - case 0x10: /* SysTick Control and Status. */ - val = s->systick.control; - s->systick.control &= ~SYSTICK_COUNTFLAG; - return val; - case 0x14: /* SysTick Reload Value. */ - return s->systick.reload; - case 0x18: /* SysTick Current Value. */ - { - int64_t t; - if ((s->systick.control & SYSTICK_ENABLE) == 0) - return 0; - t = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); - if (t >= s->systick.tick) - return 0; - val = ((s->systick.tick - (t + 1)) / systick_scale(s)) + 1; - /* The interrupt in triggered when the timer reaches zero. - However the counter is not reloaded until the next clock - tick. This is a hack to return zero during the first tick. */ - if (val > s->systick.reload) - val = 0; - return val; - } - case 0x1c: /* SysTick Calibration Value. */ - return 10000; case 0xd00: /* CPUID Base. */ return cpu->midr; case 0xd04: /* Interrupt Control State. */ @@ -620,40 +537,8 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset) static void nvic_writel(NVICState *s, uint32_t offset, uint32_t value) { ARMCPU *cpu = s->cpu; - uint32_t oldval; + switch (offset) { - case 0x10: /* SysTick Control and Status. */ - oldval = s->systick.control; - s->systick.control &= 0xfffffff8; - s->systick.control |= value & 7; - if ((oldval ^ value) & SYSTICK_ENABLE) { - int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); - if (value & SYSTICK_ENABLE) { - if (s->systick.tick) { - s->systick.tick += now; - timer_mod(s->systick.timer, s->systick.tick); - } else { - systick_reload(s, 1); - } - } else { - timer_del(s->systick.timer); - s->systick.tick -= now; - if (s->systick.tick < 0) - s->systick.tick = 0; - } - } else if ((oldval ^ value) & SYSTICK_CLKSOURCE) { - /* This is a hack. Force the timer to be reloaded - when the reference clock is changed. */ - systick_reload(s, 1); - } - break; - case 0x14: /* SysTick Reload Value. */ - s->systick.reload = value; - break; - case 0x18: /* SysTick Current Value. Writes reload the timer. */ - systick_reload(s, 1); - s->systick.control &= ~SYSTICK_COUNTFLAG; - break; case 0xd04: /* Interrupt Control State. */ if (value & (1 << 31)) { armv7m_nvic_set_pending(s, ARMV7M_EXCP_NMI); @@ -952,16 +837,12 @@ static const VMStateDescription vmstate_VecInfo = { static const VMStateDescription vmstate_nvic = { .name = "armv7m_nvic", - .version_id = 3, - .minimum_version_id = 3, + .version_id = 4, + .minimum_version_id = 4, .post_load = &nvic_post_load, .fields = (VMStateField[]) { VMSTATE_STRUCT_ARRAY(vectors, NVICState, NVIC_MAX_VECTORS, 1, vmstate_VecInfo, VecInfo), - VMSTATE_UINT32(systick.control, NVICState), - VMSTATE_UINT32(systick.reload, NVICState), - VMSTATE_INT64(systick.tick, NVICState), - VMSTATE_TIMER_PTR(systick.timer, NVICState), VMSTATE_UINT32(prigroup, NVICState), VMSTATE_END_OF_LIST() } @@ -999,13 +880,26 @@ static void armv7m_nvic_reset(DeviceState *dev) s->exception_prio = NVIC_NOEXC_PRIO; s->vectpending = 0; +} - systick_reset(s); +static void nvic_systick_trigger(void *opaque, int n, int level) +{ + NVICState *s = opaque; + + if (level) { + /* SysTick just asked us to pend its exception. + * (This is different from an external interrupt line's + * behaviour.) + */ + armv7m_nvic_set_pending(s, ARMV7M_EXCP_SYSTICK); + } } static void armv7m_nvic_realize(DeviceState *dev, Error **errp) { NVICState *s = NVIC(dev); + SysBusDevice *systick_sbd; + Error *err = NULL; s->cpu = ARM_CPU(qemu_get_cpu(0)); assert(s->cpu); @@ -1020,10 +914,19 @@ static void armv7m_nvic_realize(DeviceState *dev, Error **errp) /* include space for internal exception vectors */ s->num_irq += NVIC_FIRST_IRQ; + object_property_set_bool(OBJECT(&s->systick), true, "realized", &err); + if (err != NULL) { + error_propagate(errp, err); + return; + } + systick_sbd = SYS_BUS_DEVICE(&s->systick); + sysbus_connect_irq(systick_sbd, 0, + qdev_get_gpio_in_named(dev, "systick-trigger", 0)); + /* The NVIC and System Control Space (SCS) starts at 0xe000e000 * and looks like this: * 0x004 - ICTR - * 0x010 - 0x1c - systick + * 0x010 - 0xff - systick * 0x100..0x7ec - NVIC * 0x7f0..0xcff - Reserved * 0xd00..0xd3c - SCS registers @@ -1041,10 +944,11 @@ static void armv7m_nvic_realize(DeviceState *dev, Error **errp) memory_region_init_io(&s->sysregmem, OBJECT(s), &nvic_sysreg_ops, s, "nvic_sysregs", 0x1000); memory_region_add_subregion(&s->container, 0, &s->sysregmem); + memory_region_add_subregion_overlap(&s->container, 0x10, + sysbus_mmio_get_region(systick_sbd, 0), + 1); sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->container); - - s->systick.timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, systick_timer_tick, s); } static void armv7m_nvic_instance_init(Object *obj) @@ -1059,8 +963,12 @@ static void armv7m_nvic_instance_init(Object *obj) NVICState *nvic = NVIC(obj); SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + object_initialize(&nvic->systick, sizeof(nvic->systick), TYPE_SYSTICK); + qdev_set_parent_bus(DEVICE(&nvic->systick), sysbus_get_default()); + sysbus_init_irq(sbd, &nvic->excpout); qdev_init_gpio_out_named(dev, &nvic->sysresetreq, "SYSRESETREQ", 1); + qdev_init_gpio_in_named(dev, nvic_systick_trigger, "systick-trigger", 1); } static void armv7m_nvic_class_init(ObjectClass *klass, void *data) diff --git a/hw/timer/armv7m_systick.c b/hw/timer/armv7m_systick.c new file mode 100644 index 0000000..3fd5e72 --- /dev/null +++ b/hw/timer/armv7m_systick.c @@ -0,0 +1,239 @@ +/* + * ARMv7M SysTick timer + * + * Copyright (c) 2006-2007 CodeSourcery. + * Written by Paul Brook + * Copyright (c) 2017 Linaro Ltd + * Written by Peter Maydell + * + * This code is licensed under the GPL (version 2 or later). + */ + +#include "qemu/osdep.h" +#include "hw/timer/armv7m_systick.h" +#include "qemu-common.h" +#include "hw/sysbus.h" +#include "qemu/timer.h" +#include "qemu/log.h" +#include "trace.h" + +/* qemu timers run at 1GHz. We want something closer to 1MHz. */ +#define SYSTICK_SCALE 1000ULL + +#define SYSTICK_ENABLE (1 << 0) +#define SYSTICK_TICKINT (1 << 1) +#define SYSTICK_CLKSOURCE (1 << 2) +#define SYSTICK_COUNTFLAG (1 << 16) + +int system_clock_scale; + +/* Conversion factor from qemu timer to SysTick frequencies. */ +static inline int64_t systick_scale(SysTickState *s) +{ + if (s->control & SYSTICK_CLKSOURCE) { + return system_clock_scale; + } else { + return 1000; + } +} + +static void systick_reload(SysTickState *s, int reset) +{ + /* The Cortex-M3 Devices Generic User Guide says that "When the + * ENABLE bit is set to 1, the counter loads the RELOAD value from the + * SYST RVR register and then counts down". So, we need to check the + * ENABLE bit before reloading the value. + */ + trace_systick_reload(); + + if ((s->control & SYSTICK_ENABLE) == 0) { + return; + } + + if (reset) { + s->tick = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + } + s->tick += (s->reload + 1) * systick_scale(s); + timer_mod(s->timer, s->tick); +} + +static void systick_timer_tick(void *opaque) +{ + SysTickState *s = (SysTickState *)opaque; + + trace_systick_timer_tick(); + + s->control |= SYSTICK_COUNTFLAG; + if (s->control & SYSTICK_TICKINT) { + /* Tell the NVIC to pend the SysTick exception */ + qemu_irq_pulse(s->irq); + } + if (s->reload == 0) { + s->control &= ~SYSTICK_ENABLE; + } else { + systick_reload(s, 0); + } +} + +static uint64_t systick_read(void *opaque, hwaddr addr, unsigned size) +{ + SysTickState *s = opaque; + uint32_t val; + + switch (addr) { + case 0x0: /* SysTick Control and Status. */ + val = s->control; + s->control &= ~SYSTICK_COUNTFLAG; + break; + case 0x4: /* SysTick Reload Value. */ + val = s->reload; + break; + case 0x8: /* SysTick Current Value. */ + { + int64_t t; + + if ((s->control & SYSTICK_ENABLE) == 0) { + val = 0; + break; + } + t = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + if (t >= s->tick) { + val = 0; + break; + } + val = ((s->tick - (t + 1)) / systick_scale(s)) + 1; + /* The interrupt in triggered when the timer reaches zero. + However the counter is not reloaded until the next clock + tick. This is a hack to return zero during the first tick. */ + if (val > s->reload) { + val = 0; + } + break; + } + case 0xc: /* SysTick Calibration Value. */ + val = 10000; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "SysTick: Bad read offset 0x%" HWADDR_PRIx "\n", addr); + break; + } + + trace_systick_read(addr, val, size); + return val; +} + +static void systick_write(void *opaque, hwaddr addr, + uint64_t value, unsigned size) +{ + SysTickState *s = opaque; + + trace_systick_write(addr, value, size); + + switch (addr) { + case 0x0: /* SysTick Control and Status. */ + { + uint32_t oldval = s->control; + + s->control &= 0xfffffff8; + s->control |= value & 7; + if ((oldval ^ value) & SYSTICK_ENABLE) { + int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + if (value & SYSTICK_ENABLE) { + if (s->tick) { + s->tick += now; + timer_mod(s->timer, s->tick); + } else { + systick_reload(s, 1); + } + } else { + timer_del(s->timer); + s->tick -= now; + if (s->tick < 0) { + s->tick = 0; + } + } + } else if ((oldval ^ value) & SYSTICK_CLKSOURCE) { + /* This is a hack. Force the timer to be reloaded + when the reference clock is changed. */ + systick_reload(s, 1); + } + break; + } + case 0x4: /* SysTick Reload Value. */ + s->reload = value; + break; + case 0x8: /* SysTick Current Value. Writes reload the timer. */ + systick_reload(s, 1); + s->control &= ~SYSTICK_COUNTFLAG; + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "SysTick: Bad write offset 0x%" HWADDR_PRIx "\n", addr); + } +} + +static const MemoryRegionOps systick_ops = { + .read = systick_read, + .write = systick_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .valid.min_access_size = 4, + .valid.max_access_size = 4, +}; + +static void systick_reset(DeviceState *dev) +{ + SysTickState *s = SYSTICK(dev); + + s->control = 0; + s->reload = 0; + s->tick = 0; + timer_del(s->timer); +} + +static void systick_instance_init(Object *obj) +{ + SysBusDevice *sbd = SYS_BUS_DEVICE(obj); + SysTickState *s = SYSTICK(obj); + + memory_region_init_io(&s->iomem, obj, &systick_ops, s, "systick", 0xe0); + sysbus_init_mmio(sbd, &s->iomem); + sysbus_init_irq(sbd, &s->irq); + s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, systick_timer_tick, s); +} + +static const VMStateDescription vmstate_systick = { + .name = "armv7m_systick", + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_UINT32(control, SysTickState), + VMSTATE_UINT32(reload, SysTickState), + VMSTATE_INT64(tick, SysTickState), + VMSTATE_TIMER_PTR(timer, SysTickState), + VMSTATE_END_OF_LIST() + } +}; + +static void systick_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->vmsd = &vmstate_systick; + dc->reset = systick_reset; +} + +static const TypeInfo armv7m_systick_info = { + .name = TYPE_SYSTICK, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_init = systick_instance_init, + .instance_size = sizeof(SysTickState), + .class_init = systick_class_init, +}; + +static void armv7m_systick_register_types(void) +{ + type_register_static(&armv7m_systick_info); +} + +type_init(armv7m_systick_register_types) diff --git a/hw/timer/trace-events b/hw/timer/trace-events index 3495c41..d17cfe6 100644 --- a/hw/timer/trace-events +++ b/hw/timer/trace-events @@ -49,3 +49,9 @@ aspeed_timer_ctrl_pulse_enable(uint8_t i, bool enable) "Timer %" PRIu8 ": %d" aspeed_timer_set_ctrl2(uint32_t value) "Value: 0x%" PRIx32 aspeed_timer_set_value(int timer, int reg, uint32_t value) "Timer %d register %d: 0x%" PRIx32 aspeed_timer_read(uint64_t offset, unsigned size, uint64_t value) "From 0x%" PRIx64 ": of size %u: 0x%" PRIx64 + +# hw/timer/armv7m_systick.c +systick_reload(void) "systick reload" +systick_timer_tick(void) "systick reload" +systick_read(uint64_t addr, uint32_t value, unsigned size) "systick read addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u" +systick_write(uint64_t addr, uint32_t value, unsigned size) "systick write addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u" -- 2.7.4