From: Aaron Lindsay <alindsay@codeaurora.org>

During code generation, surround CPSR writes and exception returns which
call the EL change hooks with gen_io_start/end. The immediate need is
for the PMU to access the clock and icount during EL change to support
mode filtering.

Signed-off-by: Aaron Lindsay <alindsay@codeaurora.org>
Message-id: 1523997485-1905-9-git-send-email-alindsay@codeaurora.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/translate-a64.c |  6 ++++++
 target/arm/translate.c     | 12 ++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index c91329249d..bff4e13bf6 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1930,7 +1930,13 @@ static void disas_uncond_b_reg(DisasContext *s, uint32_t insn)
             unallocated_encoding(s);
             return;
         }
+        if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+            gen_io_start();
+        }
         gen_helper_exception_return(cpu_env);
+        if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+            gen_io_end();
+        }
         /* Must exit loop to check un-masked IRQs */
         s->base.is_jmp = DISAS_EXIT;
         return;
diff --git a/target/arm/translate.c b/target/arm/translate.c
index db1ce6510a..9bc2ce1a0b 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -4548,7 +4548,13 @@ static void gen_rfe(DisasContext *s, TCGv_i32 pc, TCGv_i32 cpsr)
      * appropriately depending on the new Thumb bit, so it must
      * be called after storing the new PC.
      */
+    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+        gen_io_start();
+    }
     gen_helper_cpsr_write_eret(cpu_env, cpsr);
+    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+        gen_io_end();
+    }
     tcg_temp_free_i32(cpsr);
     /* Must exit loop to check un-masked IRQs */
     s->base.is_jmp = DISAS_EXIT;
@@ -9843,7 +9849,13 @@ static void disas_arm_insn(DisasContext *s, unsigned int insn)
                 if (exc_return) {
                     /* Restore CPSR from SPSR.  */
                     tmp = load_cpu_field(spsr);
+                    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+                        gen_io_start();
+                    }
                     gen_helper_cpsr_write_eret(cpu_env, tmp);
+                    if (tb_cflags(s->base.tb) & CF_USE_ICOUNT) {
+                        gen_io_end();
+                    }
                     tcg_temp_free_i32(tmp);
                     /* Must exit loop to check un-masked IRQs */
                     s->base.is_jmp = DISAS_EXIT;
-- 
2.17.0