hw/intc: Support 32/64-bit mtimecmp and mtime accesses in RISC-V ACLINT

RISC-V privilege spec defines that:

* In RV32, memory-mapped writes to mtimecmp modify only one 32-bit part
  of the register.
* For RV64, naturally aligned 64-bit memory accesses to the mtime and
  mtimecmp registers are additionally supported and are atomic.

It's possible to perform both 32/64-bit read/write accesses to both
mtimecmp and mtime registers.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Jim Shu <jim.shu@sifive.com>
Message-Id: <20220420080901.14655-3-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
master
Frank Chang 2022-04-20 16:08:58 +08:00 committed by Alistair Francis
parent 231a90c085
commit d42df0ea5d
1 changed files with 27 additions and 15 deletions

View File

@ -126,9 +126,9 @@ static uint64_t riscv_aclint_mtimer_read(void *opaque, hwaddr addr,
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid hartid: %zu", hartid);
} else if ((addr & 0x7) == 0) {
/* timecmp_lo */
/* timecmp_lo for RV32/RV64 or timecmp for RV64 */
uint64_t timecmp = env->timecmp;
return timecmp & 0xFFFFFFFF;
return (size == 4) ? (timecmp & 0xFFFFFFFF) : timecmp;
} else if ((addr & 0x7) == 4) {
/* timecmp_hi */
uint64_t timecmp = env->timecmp;
@ -139,8 +139,9 @@ static uint64_t riscv_aclint_mtimer_read(void *opaque, hwaddr addr,
return 0;
}
} else if (addr == mtimer->time_base) {
/* time_lo */
return cpu_riscv_read_rtc(mtimer->timebase_freq) & 0xFFFFFFFF;
/* time_lo for RV32/RV64 or timecmp for RV64 */
uint64_t rtc = cpu_riscv_read_rtc(mtimer->timebase_freq);
return (size == 4) ? (rtc & 0xFFFFFFFF) : rtc;
} else if (addr == mtimer->time_base + 4) {
/* time_hi */
return (cpu_riscv_read_rtc(mtimer->timebase_freq) >> 32) & 0xFFFFFFFF;
@ -167,18 +168,29 @@ static void riscv_aclint_mtimer_write(void *opaque, hwaddr addr,
qemu_log_mask(LOG_GUEST_ERROR,
"aclint-mtimer: invalid hartid: %zu", hartid);
} else if ((addr & 0x7) == 0) {
/* timecmp_lo */
uint64_t timecmp_hi = env->timecmp >> 32;
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
timecmp_hi << 32 | (value & 0xFFFFFFFF),
mtimer->timebase_freq);
return;
if (size == 4) {
/* timecmp_lo for RV32/RV64 */
uint64_t timecmp_hi = env->timecmp >> 32;
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
timecmp_hi << 32 | (value & 0xFFFFFFFF),
mtimer->timebase_freq);
} else {
/* timecmp for RV64 */
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
value, mtimer->timebase_freq);
}
} else if ((addr & 0x7) == 4) {
/* timecmp_hi */
uint64_t timecmp_lo = env->timecmp;
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
value << 32 | (timecmp_lo & 0xFFFFFFFF),
mtimer->timebase_freq);
if (size == 4) {
/* timecmp_hi for RV32/RV64 */
uint64_t timecmp_lo = env->timecmp;
riscv_aclint_mtimer_write_timecmp(mtimer, RISCV_CPU(cpu), hartid,
value << 32 | (timecmp_lo & 0xFFFFFFFF),
mtimer->timebase_freq);
} 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",