[PATCH v5 04/10] target/ppc: Put dbcr0 single-step bits into hflags

[Richard Henderson]

Because these bits were not in hflags, the code generated
for single-stepping on BookE was essentially random.
Recompute hflags when storing to dbcr0.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/ppc/helper_regs.c | 24 +++++++++++++++++-------
 target/ppc/misc_helper.c |  3 +++
 target/ppc/translate.c   | 11 -----------
 3 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/target/ppc/helper_regs.c b/target/ppc/helper_regs.c
index df9673b90f..e345966b6b 100644
--- a/target/ppc/helper_regs.c
+++ b/target/ppc/helper_regs.c
@@ -114,13 +114,23 @@ void hreg_compute_hflags(CPUPPCState *env)
         hflags |= le << MSR_LE;
     }
 
-    if (ppc_flags & POWERPC_FLAG_BE) {
-        QEMU_BUILD_BUG_ON(MSR_BE != HFLAGS_BE);
-        msr_mask |= 1 << MSR_BE;
-    }
-    if (ppc_flags & POWERPC_FLAG_SE) {
-        QEMU_BUILD_BUG_ON(MSR_SE != HFLAGS_SE);
-        msr_mask |= 1 << MSR_SE;
+    if (ppc_flags & POWERPC_FLAG_DE) {
+        target_ulong dbcr0 = env->spr[SPR_BOOKE_DBCR0];
+        if (dbcr0 & DBCR0_ICMP) {
+            hflags |= 1 << HFLAGS_SE;
+        }
+        if (dbcr0 & DBCR0_BRT) {
+            hflags |= 1 << HFLAGS_BE;
+        }
+    } else {
+        if (ppc_flags & POWERPC_FLAG_BE) {
+            QEMU_BUILD_BUG_ON(MSR_BE != HFLAGS_BE);
+            msr_mask |= 1 << MSR_BE;
+        }
+        if (ppc_flags & POWERPC_FLAG_SE) {
+            QEMU_BUILD_BUG_ON(MSR_SE != HFLAGS_SE);
+            msr_mask |= 1 << MSR_SE;
+        }
     }
 
     if (msr_is_64bit(env, msr)) {
diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index b04b4d7c6e..002958be26 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -215,6 +215,9 @@ void helper_store_403_pbr(CPUPPCState *env, uint32_t num, 
target_ulong value)
 
 void helper_store_40x_dbcr0(CPUPPCState *env, target_ulong val)
 {
+    /* Bits 26 & 27 affect single-stepping. */
+    hreg_compute_hflags(env);
+    /* Bits 28 & 29 affect reset or shutdown. */
     store_40x_dbcr0(env, val);
 }
 
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index a85b890bb0..7912495f28 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -7923,17 +7923,6 @@ static void ppc_tr_init_disas_context(DisasContextBase 
*dcbase, CPUState *cs)
     if ((hflags >> HFLAGS_BE) & 1) {
         ctx->singlestep_enabled |= CPU_BRANCH_STEP;
     }
-    if ((env->flags & POWERPC_FLAG_DE) && msr_de) {
-        ctx->singlestep_enabled = 0;
-        target_ulong dbcr0 = env->spr[SPR_BOOKE_DBCR0];
-        if (dbcr0 & DBCR0_ICMP) {
-            ctx->singlestep_enabled |= CPU_SINGLE_STEP;
-        }
-        if (dbcr0 & DBCR0_BRT) {
-            ctx->singlestep_enabled |= CPU_BRANCH_STEP;
-        }
-
-    }
     if (unlikely(ctx->base.singlestep_enabled)) {
         ctx->singlestep_enabled |= GDBSTUB_SINGLE_STEP;
     }
-- 
2.25.1