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authorPeter Maydell <peter.maydell@linaro.org>2014-10-30 15:48:51 +0000
committerPeter Maydell <peter.maydell@linaro.org>2014-11-04 12:05:23 +0000
commitb5c633c5bd6993df1bf3401d94042fb8a910a92a (patch)
treecdffe89d50200c7f4098a45773d2b1e099b238b7 /target-arm/cpu.c
parentf4df22102a0081ff1bd0df4cb5552411e410eb3e (diff)
downloadqemu-b5c633c5bd6993df1bf3401d94042fb8a910a92a.zip
target-arm: Separate out M profile cpu_exec_interrupt handling
The M profile cpu_exec_interrupt handling is fairly simple but does include an M profile specific oddity (disabling interrupts for certain PC values). A/R profile handling on the other hand is getting rapidly more complicated with the support for EL2 and EL3. Split the M profile code out into its own implementation of cpu_exec_interrupt to keep these two things out of each others' way. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com> Message-id: 1414684132-23971-2-git-send-email-peter.maydell@linaro.org
Diffstat (limited to 'target-arm/cpu.c')
-rw-r--r--target-arm/cpu.c49
1 files changed, 39 insertions, 10 deletions
diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index e0b82a6704..5ce7350ce6 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -203,15 +203,6 @@ bool arm_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
cc->do_interrupt(cs);
ret = true;
}
- /* ARMv7-M interrupt return works by loading a magic value
- into the PC. On real hardware the load causes the
- return to occur. The qemu implementation performs the
- jump normally, then does the exception return when the
- CPU tries to execute code at the magic address.
- This will cause the magic PC value to be pushed to
- the stack if an interrupt occurred at the wrong time.
- We avoid this by disabling interrupts when
- pc contains a magic address. */
if (interrupt_request & CPU_INTERRUPT_HARD
&& arm_excp_unmasked(cs, EXCP_IRQ)) {
cs->exception_index = EXCP_IRQ;
@@ -234,6 +225,42 @@ bool arm_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
return ret;
}
+#if !defined(CONFIG_USER_ONLY) || !defined(TARGET_AARCH64)
+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 return works by loading a magic value
+ * into the PC. On real hardware the load causes the
+ * return to occur. The qemu implementation performs the
+ * jump normally, then does the exception return when the
+ * CPU tries to execute code at the magic address.
+ * This will cause the magic PC value to be pushed to
+ * the stack if an interrupt occurred at the wrong time.
+ * We avoid this by disabling interrupts when
+ * pc contains a magic address.
+ */
+ if (interrupt_request & CPU_INTERRUPT_HARD
+ && !(env->daif & PSTATE_I)
+ && (env->regs[15] < 0xfffffff0)) {
+ cs->exception_index = EXCP_IRQ;
+ cc->do_interrupt(cs);
+ ret = true;
+ }
+ return ret;
+}
+#endif
+
#ifndef CONFIG_USER_ONLY
static void arm_cpu_set_irq(void *opaque, int irq, int level)
{
@@ -670,11 +697,13 @@ static void cortex_m3_initfn(Object *obj)
static void arm_v7m_class_init(ObjectClass *oc, void *data)
{
-#ifndef CONFIG_USER_ONLY
CPUClass *cc = CPU_CLASS(oc);
+#ifndef CONFIG_USER_ONLY
cc->do_interrupt = arm_v7m_cpu_do_interrupt;
#endif
+
+ cc->cpu_exec_interrupt = arm_v7m_cpu_exec_interrupt;
}
static const ARMCPRegInfo cortexa8_cp_reginfo[] = {