target/arm: Implement ESB instruction

Check for and defer any pending virtual SError.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220506180242.216785-17-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 76499ffa14..390b6578a8 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -960,3 +960,46 @@ void HELPER(probe_access)(CPUARMState *env, target_ulong ptr,
                      access_type, mmu_idx, ra);
     }
 }
+
+/*
+ * This function corresponds to AArch64.vESBOperation().
+ * Note that the AArch32 version is not functionally different.
+ */
+void HELPER(vesb)(CPUARMState *env)
+{
+    /*
+     * The EL2Enabled() check is done inside arm_hcr_el2_eff,
+     * and will return HCR_EL2.VSE == 0, so nothing happens.
+     */
+    uint64_t hcr = arm_hcr_el2_eff(env);
+    bool enabled = !(hcr & HCR_TGE) && (hcr & HCR_AMO);
+    bool pending = enabled && (hcr & HCR_VSE);
+    bool masked  = (env->daif & PSTATE_A);
+
+    /* If VSE pending and masked, defer the exception.  */
+    if (pending && masked) {
+        uint32_t syndrome;
+
+        if (arm_el_is_aa64(env, 1)) {
+            /* Copy across IDS and ISS from VSESR. */
+            syndrome = env->cp15.vsesr_el2 & 0x1ffffff;
+        } else {
+            ARMMMUFaultInfo fi = { .type = ARMFault_AsyncExternal };
+
+            if (extended_addresses_enabled(env)) {
+                syndrome = arm_fi_to_lfsc(&fi);
+            } else {
+                syndrome = arm_fi_to_sfsc(&fi);
+            }
+            /* Copy across AET and ExT from VSESR. */
+            syndrome |= env->cp15.vsesr_el2 & 0xd000;
+        }
+
+        /* Set VDISR_EL2.A along with the syndrome. */
+        env->cp15.vdisr_el2 = syndrome | (1u << 31);
+
+        /* Clear pending virtual SError */
+        env->cp15.hcr_el2 &= ~HCR_VSE;
+        cpu_reset_interrupt(env_cpu(env), CPU_INTERRUPT_VSERR);
+    }
+}