target/riscv: Add functions for common matching conditions of trigger

According to RISC-V Debug specification version 0.13 [1] (also applied
to version 1.0 [2] but it has not been ratified yet), there are several
common matching conditions before firing a trigger, including the
enabled privilege levels of the trigger.

This commit adds trigger_common_match() to prepare the common matching
conditions for the type 2/3/6 triggers. For now, we just implement
trigger_priv_match() to check if the enabled privilege levels of the
trigger match CPU's current privilege level.

Remove the related code in riscv_cpu_debug_check_breakpoint() and invoke
trigger_common_match() to check the privilege levels of the type 2 and
type 6 triggers for the breakpoints.

This commit also changes the behavior of looping the triggers. In
previous implementation, if we have a type 2 trigger and
env->virt_enabled is true, we directly return false to stop the loop.
Now we keep looping all the triggers until we find a matched trigger.

Only the execution bit and the executed PC should be futher checked in
riscv_cpu_debug_check_breakpoint().

[1]: https://github.com/riscv/riscv-debug-spec/releases/tag/task_group_vote
[2]: https://github.com/riscv/riscv-debug-spec/releases/tag/1.0.0-rc1-asciidoc

Signed-off-by: Alvin Chang <alvinga@andestech.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <20240626132247.2761286-2-alvinga@andestech.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This commit is contained in:
Alvin Chang 2024-06-26 21:22:45 +08:00 committed by Alistair Francis
parent cb5b50d91d
commit 5e20b88953

View file

@ -241,6 +241,76 @@ static void do_trigger_action(CPURISCVState *env, target_ulong trigger_index)
}
}
/*
* Check the privilege level of specific trigger matches CPU's current privilege
* level.
*/
static bool trigger_priv_match(CPURISCVState *env, trigger_type_t type,
int trigger_index)
{
target_ulong ctrl = env->tdata1[trigger_index];
switch (type) {
case TRIGGER_TYPE_AD_MATCH:
/* type 2 trigger cannot be fired in VU/VS mode */
if (env->virt_enabled) {
return false;
}
/* check U/S/M bit against current privilege level */
if ((ctrl >> 3) & BIT(env->priv)) {
return true;
}
break;
case TRIGGER_TYPE_AD_MATCH6:
if (env->virt_enabled) {
/* check VU/VS bit against current privilege level */
if ((ctrl >> 23) & BIT(env->priv)) {
return true;
}
} else {
/* check U/S/M bit against current privilege level */
if ((ctrl >> 3) & BIT(env->priv)) {
return true;
}
}
break;
case TRIGGER_TYPE_INST_CNT:
if (env->virt_enabled) {
/* check VU/VS bit against current privilege level */
if ((ctrl >> 25) & BIT(env->priv)) {
return true;
}
} else {
/* check U/S/M bit against current privilege level */
if ((ctrl >> 6) & BIT(env->priv)) {
return true;
}
}
break;
case TRIGGER_TYPE_INT:
case TRIGGER_TYPE_EXCP:
case TRIGGER_TYPE_EXT_SRC:
qemu_log_mask(LOG_UNIMP, "trigger type: %d is not supported\n", type);
break;
case TRIGGER_TYPE_NO_EXIST:
case TRIGGER_TYPE_UNAVAIL:
qemu_log_mask(LOG_GUEST_ERROR, "trigger type: %d does not exist\n",
type);
break;
default:
g_assert_not_reached();
}
return false;
}
/* Common matching conditions for all types of the triggers. */
static bool trigger_common_match(CPURISCVState *env, trigger_type_t type,
int trigger_index)
{
return trigger_priv_match(env, type, trigger_index);
}
/* type 2 trigger */
static uint32_t type2_breakpoint_size(CPURISCVState *env, target_ulong ctrl)
@ -785,22 +855,18 @@ bool riscv_cpu_debug_check_breakpoint(CPUState *cs)
for (i = 0; i < RV_MAX_TRIGGERS; i++) {
trigger_type = get_trigger_type(env, i);
if (!trigger_common_match(env, trigger_type, i)) {
continue;
}
switch (trigger_type) {
case TRIGGER_TYPE_AD_MATCH:
/* type 2 trigger cannot be fired in VU/VS mode */
if (env->virt_enabled) {
return false;
}
ctrl = env->tdata1[i];
pc = env->tdata2[i];
if ((ctrl & TYPE2_EXEC) && (bp->pc == pc)) {
/* check U/S/M bit against current privilege level */
if ((ctrl >> 3) & BIT(env->priv)) {
env->badaddr = pc;
return true;
}
env->badaddr = pc;
return true;
}
break;
case TRIGGER_TYPE_AD_MATCH6:
@ -808,19 +874,8 @@ bool riscv_cpu_debug_check_breakpoint(CPUState *cs)
pc = env->tdata2[i];
if ((ctrl & TYPE6_EXEC) && (bp->pc == pc)) {
if (env->virt_enabled) {
/* check VU/VS bit against current privilege level */
if ((ctrl >> 23) & BIT(env->priv)) {
env->badaddr = pc;
return true;
}
} else {
/* check U/S/M bit against current privilege level */
if ((ctrl >> 3) & BIT(env->priv)) {
env->badaddr = pc;
return true;
}
}
env->badaddr = pc;
return true;
}
break;
default: