target/xtensa: fix access to the INTERRUPT SR

INTERRUPT special register may be changed both by the core (by writing
to INTSET and INTCLEAR registers) and by external events (by triggering
and clearing HW IRQs). In MTTCG this state must be protected from
concurrent access, otherwise interrupts may be lost or spurious
interrupts may be detected.

Use atomic operations to change INTSET SR.
Fix wsr.intset so that it soesn't clear any bits.
Fix wsr.intclear so that it doesn't clear bit that corresponds to NMI.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov 2019-01-23 19:26:52 -08:00
parent fff7bf1450
commit fa92bd4af7
5 changed files with 21 additions and 14 deletions

View File

@ -68,9 +68,9 @@ static void xtensa_set_irq(void *opaque, int irq, int active)
uint32_t irq_bit = 1 << irq;
if (active) {
env->sregs[INTSET] |= irq_bit;
atomic_or(&env->sregs[INTSET], irq_bit);
} else if (env->config->interrupt[irq].inttype == INTTYPE_LEVEL) {
env->sregs[INTSET] &= ~irq_bit;
atomic_and(&env->sregs[INTSET], ~irq_bit);
}
check_interrupts(env);

View File

@ -127,6 +127,19 @@ void HELPER(check_interrupts)(CPUXtensaState *env)
qemu_mutex_unlock_iothread();
}
void HELPER(intset)(CPUXtensaState *env, uint32_t v)
{
atomic_or(&env->sregs[INTSET],
v & env->config->inttype_mask[INTTYPE_SOFTWARE]);
}
void HELPER(intclear)(CPUXtensaState *env, uint32_t v)
{
atomic_and(&env->sregs[INTSET],
~(v & (env->config->inttype_mask[INTTYPE_SOFTWARE] |
env->config->inttype_mask[INTTYPE_EDGE])));
}
static uint32_t relocated_vector(CPUXtensaState *env, uint32_t vector)
{
if (xtensa_option_enabled(env->config,

View File

@ -22,6 +22,8 @@ DEF_HELPER_1(update_ccount, void, env)
DEF_HELPER_2(wsr_ccount, void, env, i32)
DEF_HELPER_2(update_ccompare, void, env, i32)
DEF_HELPER_1(check_interrupts, void, env)
DEF_HELPER_2(intset, void, env, i32)
DEF_HELPER_2(intclear, void, env, i32)
DEF_HELPER_3(check_atomctl, void, env, i32, i32)
DEF_HELPER_2(wsr_memctl, void, env, i32)

View File

@ -62,6 +62,8 @@ void HELPER(update_ccompare)(CPUXtensaState *env, uint32_t i)
{
uint64_t dcc;
atomic_and(&env->sregs[INTSET],
~(1u << env->config->timerint[i]));
HELPER(update_ccount)(env);
dcc = (uint64_t)(env->sregs[CCOMPARE + i] - env->sregs[CCOUNT] - 1) + 1;
timer_mod(env->ccompare[i].timer,

View File

@ -646,20 +646,12 @@ static void gen_check_interrupts(DisasContext *dc)
static void gen_wsr_intset(DisasContext *dc, uint32_t sr, TCGv_i32 v)
{
tcg_gen_andi_i32(cpu_SR[sr], v,
dc->config->inttype_mask[INTTYPE_SOFTWARE]);
gen_helper_intset(cpu_env, v);
}
static void gen_wsr_intclear(DisasContext *dc, uint32_t sr, TCGv_i32 v)
{
TCGv_i32 tmp = tcg_temp_new_i32();
tcg_gen_andi_i32(tmp, v,
dc->config->inttype_mask[INTTYPE_EDGE] |
dc->config->inttype_mask[INTTYPE_NMI] |
dc->config->inttype_mask[INTTYPE_SOFTWARE]);
tcg_gen_andc_i32(cpu_SR[INTSET], cpu_SR[INTSET], tmp);
tcg_temp_free(tmp);
gen_helper_intclear(cpu_env, v);
}
static void gen_wsr_intenable(DisasContext *dc, uint32_t sr, TCGv_i32 v)
@ -706,12 +698,10 @@ static void gen_wsr_icountlevel(DisasContext *dc, uint32_t sr, TCGv_i32 v)
static void gen_wsr_ccompare(DisasContext *dc, uint32_t sr, TCGv_i32 v)
{
uint32_t id = sr - CCOMPARE;
uint32_t int_bit = 1 << dc->config->timerint[id];
TCGv_i32 tmp = tcg_const_i32(id);
assert(id < dc->config->nccompare);
tcg_gen_mov_i32(cpu_SR[sr], v);
tcg_gen_andi_i32(cpu_SR[INTSET], cpu_SR[INTSET], ~int_bit);
if (tb_cflags(dc->base.tb) & CF_USE_ICOUNT) {
gen_io_start();
}