[Qemu-devel] [PATCH v3 15/16] target-arm: Add IRQ and FIQ routing to EL2 and 3

["Edgar E. Iglesias" <edgar.iglesias@gmail.com>]

From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>

Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
---
 target-arm/cpu.h    | 12 ++++++++++++
 target-arm/helper.c | 13 +++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index 42e0ed3..bb123bd 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -1136,6 +1136,12 @@ static inline bool arm_excp_unmasked(CPUState *cs, unsigned int excp_idx)
     CPUARMState *env = cs->env_ptr;
     unsigned int cur_el = arm_current_pl(env);
     unsigned int target_el = arm_excp_target_el(cs, excp_idx);
+    /* FIXME: Use actual secure state.  */
+    bool secure = false;
+    /* Interrupts can only be hypervised and routed to
+     * EL2 if we are in NS EL0/1.
+     */
+    bool irq_can_hyp = !secure && cur_el < 2 && target_el == 2;
 
     /* Don't take exceptions if they target a lower EL.  */
     if (cur_el > target_el) {
@@ -1144,8 +1150,14 @@ static inline bool arm_excp_unmasked(CPUState *cs, unsigned int excp_idx)
 
     switch (excp_idx) {
     case EXCP_FIQ:
+        if (irq_can_hyp && (env->cp15.hcr_el2 & HCR_FMO)) {
+            return true;
+        }
         return !(env->daif & PSTATE_F);
     case EXCP_IRQ:
+        if (irq_can_hyp && (env->cp15.hcr_el2 & HCR_IMO)) {
+            return true;
+        }
         return ((IS_M(env) && env->regs[15] < 0xfffffff0)
                             || !(env->daif & PSTATE_I));
     default:
diff --git a/target-arm/helper.c b/target-arm/helper.c
index 4945f67..3afcbb2 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -3312,6 +3312,19 @@ unsigned int arm_excp_target_el(CPUState *cs, unsigned int excp_idx)
             target_el = 2;
         }
         break;
+    case EXCP_FIQ:
+    case EXCP_IRQ: {
+            const uint64_t hcr_mask = excp_idx == EXCP_FIQ ? HCR_FMO : HCR_IMO;
+            const uint32_t scr_mask = excp_idx == EXCP_FIQ ? SCR_FIQ : SCR_IRQ;
+
+            if (!secure && (env->cp15.hcr_el2 & hcr_mask)) {
+                target_el = 2;
+            }
+            if (env->cp15.scr_el3 & scr_mask) {
+                target_el = 3;
+            }
+            break;
+        }
     }
     return target_el;
 }
-- 
1.8.3.2