qemu/hw/intc/riscv_aclint.c
Atish Patra 7cbcc538f4 hw/intc: Move mtimer/mtimecmp to aclint
Historically, The mtime/mtimecmp has been part of the CPU because
they are per hart entities. However, they actually belong to aclint
which is a MMIO device.

Move them to the ACLINT device. This also emulates the real hardware
more closely.

Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Message-Id: <20220824221357.41070-2-atishp@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
2022-09-07 09:19:10 +02:00

566 lines
19 KiB
C

/*
* RISC-V ACLINT (Advanced Core Local Interruptor)
* URL: https://github.com/riscv/riscv-aclint
*
* Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
* Copyright (c) 2017 SiFive, Inc.
* Copyright (c) 2021 Western Digital Corporation or its affiliates.
*
* This provides real-time clock, timer and interprocessor interrupts.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2 or later, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "hw/sysbus.h"
#include "target/riscv/cpu.h"
#include "hw/qdev-properties.h"
#include "hw/intc/riscv_aclint.h"
#include "qemu/timer.h"
#include "hw/irq.h"
#include "migration/vmstate.h"
typedef struct riscv_aclint_mtimer_callback {
RISCVAclintMTimerState *s;
int num;
} riscv_aclint_mtimer_callback;
static uint64_t cpu_riscv_read_rtc_raw(uint32_t timebase_freq)
{
return muldiv64(qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL),
timebase_freq, NANOSECONDS_PER_SECOND);
}
static uint64_t cpu_riscv_read_rtc(void *opaque)
{
RISCVAclintMTimerState *mtimer = opaque;
return cpu_riscv_read_rtc_raw(mtimer->timebase_freq) + mtimer->time_delta;
}
/*
* Called when timecmp is written to update the QEMU timer or immediately
* trigger timer interrupt if mtimecmp <= current timer value.
*/
static void riscv_aclint_mtimer_write_timecmp(RISCVAclintMTimerState *mtimer,
RISCVCPU *cpu,
int hartid,
uint64_t value)
{
uint32_t timebase_freq = mtimer->timebase_freq;
uint64_t next;
uint64_t diff;
uint64_t rtc_r = cpu_riscv_read_rtc(mtimer);
/* Compute the relative hartid w.r.t the socket */
hartid = hartid - mtimer->hartid_base;
mtimer->timecmp[hartid] = value;
if (mtimer->timecmp[hartid] <= rtc_r) {
/*
* If we're setting an MTIMECMP value in the "past",
* immediately raise the timer interrupt
*/
qemu_irq_raise(mtimer->timer_irqs[hartid]);
return;
}
/* otherwise, set up the future timer interrupt */
qemu_irq_lower(mtimer->timer_irqs[hartid]);
diff = mtimer->timecmp[hartid] - rtc_r;
/* back to ns (note args switched in muldiv64) */
uint64_t ns_diff = muldiv64(diff, NANOSECONDS_PER_SECOND, timebase_freq);
/*
* check if ns_diff overflowed and check if the addition would potentially
* overflow
*/
if ((NANOSECONDS_PER_SECOND > timebase_freq && ns_diff < diff) ||
ns_diff > INT64_MAX) {
next = INT64_MAX;
} else {
/*
* as it is very unlikely qemu_clock_get_ns will return a value
* greater than INT64_MAX, no additional check is needed for an
* unsigned integer overflow.
*/
next = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + ns_diff;
/*
* if ns_diff is INT64_MAX next may still be outside the range
* of a signed integer.
*/
next = MIN(next, INT64_MAX);
}
timer_mod(mtimer->timers[hartid], next);
}
/*
* Callback used when the timer set using timer_mod expires.
* Should raise the timer interrupt line
*/
static void riscv_aclint_mtimer_cb(void *opaque)
{
riscv_aclint_mtimer_callback *state = opaque;
qemu_irq_raise(state->s->timer_irqs[state->num]);
}
/* CPU read MTIMER register */
static uint64_t riscv_aclint_mtimer_read(void *opaque, hwaddr addr,
unsigned size)
{
RISCVAclintMTimerState *mtimer = opaque;
if (addr >= mtimer->timecmp_base &&
addr < (mtimer->timecmp_base + (mtimer->num_harts << 3))) {
size_t hartid = mtimer->hartid_base +
((addr - mtimer->timecmp_base) >> 3);
CPUState *cpu = qemu_get_cpu(hartid);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
if (!env) {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid hartid: %zu", hartid);
} else if ((addr & 0x7) == 0) {
/* timecmp_lo for RV32/RV64 or timecmp for RV64 */
uint64_t timecmp = mtimer->timecmp[hartid];
return (size == 4) ? (timecmp & 0xFFFFFFFF) : timecmp;
} else if ((addr & 0x7) == 4) {
/* timecmp_hi */
uint64_t timecmp = mtimer->timecmp[hartid];
return (timecmp >> 32) & 0xFFFFFFFF;
} else {
qemu_log_mask(LOG_UNIMP,
"aclint-mtimer: invalid read: %08x", (uint32_t)addr);
return 0;
}
} else if (addr == mtimer->time_base) {
/* time_lo for RV32/RV64 or timecmp for RV64 */
uint64_t rtc = cpu_riscv_read_rtc(mtimer);
return (size == 4) ? (rtc & 0xFFFFFFFF) : rtc;
} else if (addr == mtimer->time_base + 4) {
/* time_hi */
return (cpu_riscv_read_rtc(mtimer) >> 32) & 0xFFFFFFFF;
}
qemu_log_mask(LOG_UNIMP,
"aclint-mtimer: invalid read: %08x", (uint32_t)addr);
return 0;
}
/* CPU write MTIMER register */
static void riscv_aclint_mtimer_write(void *opaque, hwaddr addr,
uint64_t value, unsigned size)
{
RISCVAclintMTimerState *mtimer = opaque;
int i;
if (addr >= mtimer->timecmp_base &&
addr < (mtimer->timecmp_base + (mtimer->num_harts << 3))) {
size_t hartid = mtimer->hartid_base +
((addr - mtimer->timecmp_base) >> 3);
CPUState *cpu = qemu_get_cpu(hartid);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
if (!env) {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid hartid: %zu", hartid);
} else if ((addr & 0x7) == 0) {
if (size == 4) {
/* timecmp_lo for RV32/RV64 */
uint64_t timecmp_hi = mtimer->timecmp[hartid] >> 32;
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
timecmp_hi << 32 | (value & 0xFFFFFFFF));
} else {
/* timecmp for RV64 */
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
value);
}
} else if ((addr & 0x7) == 4) {
if (size == 4) {
/* timecmp_hi for RV32/RV64 */
uint64_t timecmp_lo = mtimer->timecmp[hartid];
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
value << 32 | (timecmp_lo & 0xFFFFFFFF));
} else {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid timecmp_hi write: %08x",
(uint32_t)addr);
}
} else {
qemu_log_mask(LOG_UNIMP,
"aclint-mtimer: invalid timecmp write: %08x",
(uint32_t)addr);
}
return;
} else if (addr == mtimer->time_base || addr == mtimer->time_base + 4) {
uint64_t rtc_r = cpu_riscv_read_rtc_raw(mtimer->timebase_freq);
if (addr == mtimer->time_base) {
if (size == 4) {
/* time_lo for RV32/RV64 */
mtimer->time_delta = ((rtc_r & ~0xFFFFFFFFULL) | value) - rtc_r;
} else {
/* time for RV64 */
mtimer->time_delta = value - rtc_r;
}
} else {
if (size == 4) {
/* time_hi for RV32/RV64 */
mtimer->time_delta = (value << 32 | (rtc_r & 0xFFFFFFFF)) - rtc_r;
} else {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid time_hi write: %08x",
(uint32_t)addr);
return;
}
}
/* Check if timer interrupt is triggered for each hart. */
for (i = 0; i < mtimer->num_harts; i++) {
CPUState *cpu = qemu_get_cpu(mtimer->hartid_base + i);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
if (!env) {
continue;
}
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu),
mtimer->hartid_base + i,
mtimer->timecmp[i]);
}
return;
}
qemu_log_mask(LOG_UNIMP,
"aclint-mtimer: invalid write: %08x", (uint32_t)addr);
}
static const MemoryRegionOps riscv_aclint_mtimer_ops = {
.read = riscv_aclint_mtimer_read,
.write = riscv_aclint_mtimer_write,
.endianness = DEVICE_LITTLE_ENDIAN,
.valid = {
.min_access_size = 4,
.max_access_size = 8
},
.impl = {
.min_access_size = 4,
.max_access_size = 8,
}
};
static Property riscv_aclint_mtimer_properties[] = {
DEFINE_PROP_UINT32("hartid-base", RISCVAclintMTimerState,
hartid_base, 0),
DEFINE_PROP_UINT32("num-harts", RISCVAclintMTimerState, num_harts, 1),
DEFINE_PROP_UINT32("timecmp-base", RISCVAclintMTimerState,
timecmp_base, RISCV_ACLINT_DEFAULT_MTIMECMP),
DEFINE_PROP_UINT32("time-base", RISCVAclintMTimerState,
time_base, RISCV_ACLINT_DEFAULT_MTIME),
DEFINE_PROP_UINT32("aperture-size", RISCVAclintMTimerState,
aperture_size, RISCV_ACLINT_DEFAULT_MTIMER_SIZE),
DEFINE_PROP_UINT32("timebase-freq", RISCVAclintMTimerState,
timebase_freq, 0),
DEFINE_PROP_END_OF_LIST(),
};
static void riscv_aclint_mtimer_realize(DeviceState *dev, Error **errp)
{
RISCVAclintMTimerState *s = RISCV_ACLINT_MTIMER(dev);
int i;
memory_region_init_io(&s->mmio, OBJECT(dev), &riscv_aclint_mtimer_ops,
s, TYPE_RISCV_ACLINT_MTIMER, s->aperture_size);
sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio);
s->timer_irqs = g_new(qemu_irq, s->num_harts);
qdev_init_gpio_out(dev, s->timer_irqs, s->num_harts);
s->timers = g_new0(QEMUTimer *, s->num_harts);
s->timecmp = g_new0(uint64_t, s->num_harts);
/* Claim timer interrupt bits */
for (i = 0; i < s->num_harts; i++) {
RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(s->hartid_base + i));
if (riscv_cpu_claim_interrupts(cpu, MIP_MTIP) < 0) {
error_report("MTIP already claimed");
exit(1);
}
}
}
static void riscv_aclint_mtimer_reset_enter(Object *obj, ResetType type)
{
/*
* According to RISC-V ACLINT spec:
* - On MTIMER device reset, the MTIME register is cleared to zero.
* - On MTIMER device reset, the MTIMECMP registers are in unknown state.
*/
RISCVAclintMTimerState *mtimer = RISCV_ACLINT_MTIMER(obj);
/*
* Clear mtime register by writing to 0 it.
* Pending mtime interrupts will also be cleared at the same time.
*/
riscv_aclint_mtimer_write(mtimer, mtimer->time_base, 0, 8);
}
static const VMStateDescription vmstate_riscv_mtimer = {
.name = "riscv_mtimer",
.version_id = 1,
.minimum_version_id = 1,
.fields = (VMStateField[]) {
VMSTATE_VARRAY_UINT32(timecmp, RISCVAclintMTimerState,
num_harts, 0,
vmstate_info_uint64, uint64_t),
VMSTATE_END_OF_LIST()
}
};
static void riscv_aclint_mtimer_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = riscv_aclint_mtimer_realize;
device_class_set_props(dc, riscv_aclint_mtimer_properties);
ResettableClass *rc = RESETTABLE_CLASS(klass);
rc->phases.enter = riscv_aclint_mtimer_reset_enter;
dc->vmsd = &vmstate_riscv_mtimer;
}
static const TypeInfo riscv_aclint_mtimer_info = {
.name = TYPE_RISCV_ACLINT_MTIMER,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(RISCVAclintMTimerState),
.class_init = riscv_aclint_mtimer_class_init,
};
/*
* Create ACLINT MTIMER device.
*/
DeviceState *riscv_aclint_mtimer_create(hwaddr addr, hwaddr size,
uint32_t hartid_base, uint32_t num_harts,
uint32_t timecmp_base, uint32_t time_base, uint32_t timebase_freq,
bool provide_rdtime)
{
int i;
DeviceState *dev = qdev_new(TYPE_RISCV_ACLINT_MTIMER);
RISCVAclintMTimerState *s = RISCV_ACLINT_MTIMER(dev);
assert(num_harts <= RISCV_ACLINT_MAX_HARTS);
assert(!(addr & 0x7));
assert(!(timecmp_base & 0x7));
assert(!(time_base & 0x7));
qdev_prop_set_uint32(dev, "hartid-base", hartid_base);
qdev_prop_set_uint32(dev, "num-harts", num_harts);
qdev_prop_set_uint32(dev, "timecmp-base", timecmp_base);
qdev_prop_set_uint32(dev, "time-base", time_base);
qdev_prop_set_uint32(dev, "aperture-size", size);
qdev_prop_set_uint32(dev, "timebase-freq", timebase_freq);
sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
for (i = 0; i < num_harts; i++) {
CPUState *cpu = qemu_get_cpu(hartid_base + i);
RISCVCPU *rvcpu = RISCV_CPU(cpu);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
riscv_aclint_mtimer_callback *cb =
g_new0(riscv_aclint_mtimer_callback, 1);
if (!env) {
g_free(cb);
continue;
}
if (provide_rdtime) {
riscv_cpu_set_rdtime_fn(env, cpu_riscv_read_rtc, dev);
}
cb->s = s;
cb->num = i;
s->timers[i] = timer_new_ns(QEMU_CLOCK_VIRTUAL,
&riscv_aclint_mtimer_cb, cb);
s->timecmp[i] = 0;
qdev_connect_gpio_out(dev, i,
qdev_get_gpio_in(DEVICE(rvcpu), IRQ_M_TIMER));
}
return dev;
}
/* CPU read [M|S]SWI register */
static uint64_t riscv_aclint_swi_read(void *opaque, hwaddr addr,
unsigned size)
{
RISCVAclintSwiState *swi = opaque;
if (addr < (swi->num_harts << 2)) {
size_t hartid = swi->hartid_base + (addr >> 2);
CPUState *cpu = qemu_get_cpu(hartid);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
if (!env) {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-swi: invalid hartid: %zu", hartid);
} else if ((addr & 0x3) == 0) {
return (swi->sswi) ? 0 : ((env->mip & MIP_MSIP) > 0);
}
}
qemu_log_mask(LOG_UNIMP,
"aclint-swi: invalid read: %08x", (uint32_t)addr);
return 0;
}
/* CPU write [M|S]SWI register */
static void riscv_aclint_swi_write(void *opaque, hwaddr addr, uint64_t value,
unsigned size)
{
RISCVAclintSwiState *swi = opaque;
if (addr < (swi->num_harts << 2)) {
size_t hartid = swi->hartid_base + (addr >> 2);
CPUState *cpu = qemu_get_cpu(hartid);
CPURISCVState *env = cpu ? cpu->env_ptr : NULL;
if (!env) {
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-swi: invalid hartid: %zu", hartid);
} else if ((addr & 0x3) == 0) {
if (value & 0x1) {
qemu_irq_raise(swi->soft_irqs[hartid - swi->hartid_base]);
} else {
if (!swi->sswi) {
qemu_irq_lower(swi->soft_irqs[hartid - swi->hartid_base]);
}
}
return;
}
}
qemu_log_mask(LOG_UNIMP,
"aclint-swi: invalid write: %08x", (uint32_t)addr);
}
static const MemoryRegionOps riscv_aclint_swi_ops = {
.read = riscv_aclint_swi_read,
.write = riscv_aclint_swi_write,
.endianness = DEVICE_LITTLE_ENDIAN,
.valid = {
.min_access_size = 4,
.max_access_size = 4
}
};
static Property riscv_aclint_swi_properties[] = {
DEFINE_PROP_UINT32("hartid-base", RISCVAclintSwiState, hartid_base, 0),
DEFINE_PROP_UINT32("num-harts", RISCVAclintSwiState, num_harts, 1),
DEFINE_PROP_UINT32("sswi", RISCVAclintSwiState, sswi, false),
DEFINE_PROP_END_OF_LIST(),
};
static void riscv_aclint_swi_realize(DeviceState *dev, Error **errp)
{
RISCVAclintSwiState *swi = RISCV_ACLINT_SWI(dev);
int i;
memory_region_init_io(&swi->mmio, OBJECT(dev), &riscv_aclint_swi_ops, swi,
TYPE_RISCV_ACLINT_SWI, RISCV_ACLINT_SWI_SIZE);
sysbus_init_mmio(SYS_BUS_DEVICE(dev), &swi->mmio);
swi->soft_irqs = g_new(qemu_irq, swi->num_harts);
qdev_init_gpio_out(dev, swi->soft_irqs, swi->num_harts);
/* Claim software interrupt bits */
for (i = 0; i < swi->num_harts; i++) {
RISCVCPU *cpu = RISCV_CPU(qemu_get_cpu(swi->hartid_base + i));
/* We don't claim mip.SSIP because it is writable by software */
if (riscv_cpu_claim_interrupts(cpu, swi->sswi ? 0 : MIP_MSIP) < 0) {
error_report("MSIP already claimed");
exit(1);
}
}
}
static void riscv_aclint_swi_reset_enter(Object *obj, ResetType type)
{
/*
* According to RISC-V ACLINT spec:
* - On MSWI device reset, each MSIP register is cleared to zero.
*
* p.s. SSWI device reset does nothing since SETSIP register always reads 0.
*/
RISCVAclintSwiState *swi = RISCV_ACLINT_SWI(obj);
int i;
if (!swi->sswi) {
for (i = 0; i < swi->num_harts; i++) {
/* Clear MSIP registers by lowering software interrupts. */
qemu_irq_lower(swi->soft_irqs[i]);
}
}
}
static void riscv_aclint_swi_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = riscv_aclint_swi_realize;
device_class_set_props(dc, riscv_aclint_swi_properties);
ResettableClass *rc = RESETTABLE_CLASS(klass);
rc->phases.enter = riscv_aclint_swi_reset_enter;
}
static const TypeInfo riscv_aclint_swi_info = {
.name = TYPE_RISCV_ACLINT_SWI,
.parent = TYPE_SYS_BUS_DEVICE,
.instance_size = sizeof(RISCVAclintSwiState),
.class_init = riscv_aclint_swi_class_init,
};
/*
* Create ACLINT [M|S]SWI device.
*/
DeviceState *riscv_aclint_swi_create(hwaddr addr, uint32_t hartid_base,
uint32_t num_harts, bool sswi)
{
int i;
DeviceState *dev = qdev_new(TYPE_RISCV_ACLINT_SWI);
assert(num_harts <= RISCV_ACLINT_MAX_HARTS);
assert(!(addr & 0x3));
qdev_prop_set_uint32(dev, "hartid-base", hartid_base);
qdev_prop_set_uint32(dev, "num-harts", num_harts);
qdev_prop_set_uint32(dev, "sswi", sswi ? true : false);
sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, addr);
for (i = 0; i < num_harts; i++) {
CPUState *cpu = qemu_get_cpu(hartid_base + i);
RISCVCPU *rvcpu = RISCV_CPU(cpu);
qdev_connect_gpio_out(dev, i,
qdev_get_gpio_in(DEVICE(rvcpu),
(sswi) ? IRQ_S_SOFT : IRQ_M_SOFT));
}
return dev;
}
static void riscv_aclint_register_types(void)
{
type_register_static(&riscv_aclint_mtimer_info);
type_register_static(&riscv_aclint_swi_info);
}
type_init(riscv_aclint_register_types)