[Qemu-devel] [PATCH v4 33/33] target-arm: Limit migration of duplicate CP regs

[greg.bellows@linaro.org]

From: Greg Bellows <greg.bellows@linaro.org>

This patch adds code to mark duplicate CP register registrations as NO_MIGRATE
to avoid duplicate migrations.

Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
---
 target-arm/helper.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index 3bc55fe..7c1e2eb 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2339,7 +2339,11 @@ static const ARMCPRegInfo v8_el3_cp_reginfo[] = {
       .access = PL3_RW, .writefn = vbar_write,
       .fieldoffset = offsetof(CPUARMState, cp15.vbar_el[3]),
       .resetvalue = 0 },
-    { .name = "SCR_EL3", .state = ARM_CP_STATE_AA64,
+      /* SCR will always be registered for v7, but not necessarily for v8, so
+       * this entry is marked to allow migration to be handled by the v7
+       * registration instance.
+       */
+    { .name = "SCR_EL3", .state = ARM_CP_STATE_AA64, .type = ARM_CP_NO_MIGRATE,
       .opc0 = 3, .opc1 = 6, .crn = 1, .crm = 1, .opc2 = 0,
       .access = PL3_RW, .fieldoffset = offsetof(CPUARMState, cp15.scr_el3),
       .writefn = scr_write },
@@ -2958,6 +2962,11 @@ static void add_cpreg_to_hashtable(ARMCPU *cpu, const ARMCPRegInfo *r,
              * banked registers but later only fieldoffset is used.
              */
             r2->fieldoffset = r->bank_fieldoffsets[nsbit];
+        } else if (!nsbit) {
+            /* The register is not banked so we only want to allow migration of
+             * the non-secure instance.
+             */
+            r2->type |= ARM_CP_NO_MIGRATE;
         }
 
         if (r->state == ARM_CP_STATE_BOTH) {
-- 
1.8.3.2