[RESEND RFC PATCH v2 1/2] target/arm: Allow to inject SError interrupt

[Gavin Shan <gshan@redhat.com>]

This allows to inject SError interrupt, which will be used on receiving
QMP/HMP "nmi" command in next patch.

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 target/arm/cpu.c    | 11 +++++++++++
 target/arm/cpu.h    | 12 +++++++++---
 target/arm/helper.c |  4 ++++
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index f86e71a260..24fd77437b 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -461,6 +461,17 @@ bool arm_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
         }
     }
 
+    if (interrupt_request & CPU_INTERRUPT_SERROR) {
+        excp_idx = EXCP_SERROR;
+        target_el = arm_phys_excp_target_el(cs, excp_idx, cur_el, secure);
+        if (arm_excp_unmasked(cs, excp_idx, target_el)) {
+            cs->exception_index = excp_idx;
+            env->exception.target_el = target_el;
+            cc->do_interrupt(cs);
+            ret = true;
+        }
+    }
+
     return ret;
 }
 
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 608fcbd0b7..0bbc46ff6d 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -49,6 +49,7 @@
 #define EXCP_LAZYFP         20   /* v7M fault during lazy FP stacking */
 #define EXCP_LSERR          21   /* v8M LSERR SecureFault */
 #define EXCP_UNALIGNED      22   /* v7M UNALIGNED UsageFault */
+#define EXCP_SERROR         23   /* SError Interrupt */
 /* NB: add new EXCP_ defines to the array in arm_log_exception() too */
 
 #define ARMV7M_EXCP_RESET   1
@@ -79,9 +80,10 @@ enum {
 };
 
 /* ARM-specific interrupt pending bits.  */
-#define CPU_INTERRUPT_FIQ   CPU_INTERRUPT_TGT_EXT_1
-#define CPU_INTERRUPT_VIRQ  CPU_INTERRUPT_TGT_EXT_2
-#define CPU_INTERRUPT_VFIQ  CPU_INTERRUPT_TGT_EXT_3
+#define CPU_INTERRUPT_FIQ    CPU_INTERRUPT_TGT_EXT_1
+#define CPU_INTERRUPT_VIRQ   CPU_INTERRUPT_TGT_EXT_2
+#define CPU_INTERRUPT_VFIQ   CPU_INTERRUPT_TGT_EXT_3
+#define CPU_INTERRUPT_SERROR CPU_INTERRUPT_TGT_EXT_4
 
 /* The usual mapping for an AArch64 system register to its AArch32
  * counterpart is for the 32 bit world to have access to the lower
@@ -2731,6 +2733,10 @@ static inline bool arm_excp_unmasked(CPUState *cs, unsigned int excp_idx,
         pstate_unmasked = !(env->daif & PSTATE_I);
         break;
 
+    case EXCP_SERROR:
+       pstate_unmasked = !(env->daif & PSTATE_A);
+       break;
+
     case EXCP_VFIQ:
         if (secure || !(hcr_el2 & HCR_FMO) || (hcr_el2 & HCR_TGE)) {
             /* VFIQs are only taken when hypervized and non-secure.  */
diff --git a/target/arm/helper.c b/target/arm/helper.c
index 19a57a17da..622a1d8796 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -7980,6 +7980,7 @@ void arm_log_exception(int idx)
             [EXCP_LAZYFP] = "v7M exception during lazy FP stacking",
             [EXCP_LSERR] = "v8M LSERR UsageFault",
             [EXCP_UNALIGNED] = "v7M UNALIGNED UsageFault",
+            [EXCP_SERROR] = "SError Interrupt",
         };
 
         if (idx >= 0 && idx < ARRAY_SIZE(excnames)) {
@@ -8566,6 +8567,9 @@ static void arm_cpu_do_interrupt_aarch64(CPUState *cs)
     case EXCP_VFIQ:
         addr += 0x100;
         break;
+    case EXCP_SERROR:
+        addr += 0x180;
+        break;
     default:
         cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index);
     }
-- 
2.23.0