Re: [Qemu-devel] [PATCH v2] timer/aspeed: fix vmstate version id

[Cédric Le Goater]

> for a romulus-bmc machine, which uses a ARM1176 CPU, you can download this
> image :
> 
>    
> https://openpower.xyz/job/openbmc-build/distro=ubuntu,target=romulus/lastSuccessfulBuild/artifact/deploy/images/romulus/flash-romulus
> 
> but migration fails :
> 
>   qemu-system-arm: error while loading state for instance 0x0 of device 'cpu'
> 
> There seems to be an issue while reading the CPACR reg.

With a brutal setting of CPACR in cpu_reset, the romulus-bmc machine 
migrates. What would be a more appropriate approach ? 

Thanks,

C.  


@@ -166,6 +166,23 @@ static void arm_cpu_reset(CPUState *s)
 #if defined(CONFIG_USER_ONLY)
         /* Userspace expects access to cp10 and cp11 for FP/Neon */
         env->cp15.cpacr_el1 = deposit64(env->cp15.cpacr_el1, 20, 4, 0xf);
+#else
+        env->cp15.cpacr_el1 = 0;
+        if (arm_feature(env, ARM_FEATURE_VFP)) {
+            if (!arm_feature(env, ARM_FEATURE_NEON)) {
+                /* ASEDIS [31] bit is RAO/WI */
+                env->cp15.cpacr_el1 |= (1ull << 31);
+            }
+
+            /* VFPv3 and upwards with NEON implement 32 double precision
+             * registers (D0-D31).
+             */
+            if (!arm_feature(env, ARM_FEATURE_NEON) ||
+                    !arm_feature(env, ARM_FEATURE_VFP3)) {
+                /* D32DIS [30] is RAO/WI if D16-31 are not implemented. */
+                env->cp15.cpacr_el1 |= (1ull << 30);
+            }
+        }
 #endif
     }