nvic: Support banked exceptions in acknowledge and complete

Update armv7m_nvic_acknowledge_irq() and armv7m_nvic_complete_irq()
to handle banked exceptions:
 * acknowledge needs to use the correct vector, which may be
   in sec_vectors[]
 * acknowledge needs to return to its caller whether the
   exception should be taken to secure or non-secure state
 * complete needs its caller to tell it whether the exception
   being completed is a secure one or not

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1505240046-11454-20-git-send-email-peter.maydell@linaro.org

2 files changed, 22 insertions, 8 deletions

diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 19b0be1..d90d8d0 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -586,24 +586,32 @@ void armv7m_nvic_set_pending(void *opaque, int irq, bool secure)
 }
 
 /* Make pending IRQ active.  */
-void armv7m_nvic_acknowledge_irq(void *opaque)
+bool armv7m_nvic_acknowledge_irq(void *opaque)
 {
     NVICState *s = (NVICState *)opaque;
     CPUARMState *env = &s->cpu->env;
     const int pending = s->vectpending;
     const int running = nvic_exec_prio(s);
     VecInfo *vec;
+    bool targets_secure;
 
     assert(pending > ARMV7M_EXCP_RESET && pending < s->num_irq);
 
-    vec = &s->vectors[pending];
+    if (s->vectpending_is_s_banked) {
+        vec = &s->sec_vectors[pending];
+        targets_secure = true;
+    } else {
+        vec = &s->vectors[pending];
+        targets_secure = !exc_is_banked(s->vectpending) &&
+            exc_targets_secure(s, s->vectpending);
+    }
 
     assert(vec->enabled);
     assert(vec->pending);
 
     assert(s->vectpending_prio < running);
 
-    trace_nvic_acknowledge_irq(pending, s->vectpending_prio);
+    trace_nvic_acknowledge_irq(pending, s->vectpending_prio, targets_secure);
 
     vec->active = 1;
     vec->pending = 0;
@@ -611,9 +619,11 @@ void armv7m_nvic_acknowledge_irq(void *opaque)
     env->v7m.exception = s->vectpending;
 
     nvic_irq_update(s);
+
+    return targets_secure;
 }
 
-int armv7m_nvic_complete_irq(void *opaque, int irq)
+int armv7m_nvic_complete_irq(void *opaque, int irq, bool secure)
 {
     NVICState *s = (NVICState *)opaque;
     VecInfo *vec;
@@ -621,9 +631,13 @@ int armv7m_nvic_complete_irq(void *opaque, int irq)
 
     assert(irq > ARMV7M_EXCP_RESET && irq < s->num_irq);
 
-    vec = &s->vectors[irq];
+    if (secure && exc_is_banked(irq)) {
+        vec = &s->sec_vectors[irq];
+    } else {
+        vec = &s->vectors[irq];
+    }
 
-    trace_nvic_complete_irq(irq);
+    trace_nvic_complete_irq(irq, secure);
 
     if (!vec->active) {
         /* Tell the caller this was an illegal exception return */
diff --git a/hw/intc/trace-events b/hw/intc/trace-events
index 29bd308..b86f242 100644
--- a/hw/intc/trace-events
+++ b/hw/intc/trace-events
@@ -176,8 +176,8 @@ nvic_escalate_disabled(int irq) "NVIC escalating irq %d to HardFault: disabled"
 nvic_set_pending(int irq, bool secure, int en, int prio) "NVIC set pending irq %d secure-bank %d (enabled: %d priority %d)"
 nvic_clear_pending(int irq, bool secure, int en, int prio) "NVIC clear pending irq %d secure-bank %d (enabled: %d priority %d)"
 nvic_set_pending_level(int irq) "NVIC set pending: irq %d higher prio than vectpending: setting irq line to 1"
-nvic_acknowledge_irq(int irq, int prio) "NVIC acknowledge IRQ: %d now active (prio %d)"
-nvic_complete_irq(int irq) "NVIC complete IRQ %d"
+nvic_acknowledge_irq(int irq, int prio, bool targets_secure) "NVIC acknowledge IRQ: %d now active (prio %d targets_secure %d)"
+nvic_complete_irq(int irq, bool secure) "NVIC complete IRQ %d (secure %d)"
 nvic_set_irq_level(int irq, int level) "NVIC external irq %d level set to %d"
 nvic_sysreg_read(uint64_t addr, uint32_t value, unsigned size) "NVIC sysreg read addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"
 nvic_sysreg_write(uint64_t addr, uint32_t value, unsigned size) "NVIC sysreg write addr 0x%" PRIx64 " data 0x%" PRIx32 " size %u"