Despite having the same notation, these bits
have completely different meaning than -AR.
Use armv7m_excp_running_prio() and the highest
pending exception priority to determine
if the pending exception can interrupt preempt.
---
target-arm/cpu.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 5348028..6e3b251 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -305,19 +305,15 @@ static bool arm_v7m_cpu_exec_interrupt(CPUState *cs, int
interrupt_request)
{
CPUClass *cc = CPU_GET_CLASS(cs);
ARMCPU *cpu = ARM_CPU(cs);
- CPUARMState *env = &cpu->env;
bool ret = false;
-
- if (interrupt_request & CPU_INTERRUPT_FIQ
- && !(env->daif & PSTATE_F)) {
- cs->exception_index = EXCP_FIQ;
- cc->do_interrupt(cs);
- ret = true;
- }
+ /* ARMv7-M interrupt masking works differently than -A or -R.
+ * There is no FIQ/IRQ distinction.
+ * Instead of masking interrupt sources, the I and F bits
+ * (along with basepri) mask certain exception priority levels.
+ */
if (interrupt_request & CPU_INTERRUPT_HARD
- && !(env->daif & PSTATE_I)
- ) {
+ && (armv7m_excp_running_prio(cpu) > cpu->env.v7m.pending_prio)) {
cs->exception_index = EXCP_IRQ;
cc->do_interrupt(cs);
ret = true;
--
2.1.4
