target/ppc: SDR1 is a hypervisor resource

At present the SDR1 register - the base of the system's hashed page table
(HPT) - is represented as an SPR with supervisor read and write permission.
However, on CPUs which have a hypervisor mode, the SDR1 is a hypervisor
only resource.  Change the permission checking on the SPR to reflect this.

Now that this is done, we don't need to check for an external HPT executing
mtsdr1: an external HPT only applies when we're emulating the behaviour of
a hypervisor, rather than modelling the CPU's hypervisor mode internally,
so if we're permitted to execute mtsdr1, we don't have an external HPT.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/target/ppc/misc_helper.c b/target/ppc/misc_helper.c
index ab432bafaf..fa573dd7d2 100644
--- a/target/ppc/misc_helper.c
+++ b/target/ppc/misc_helper.c
@@ -82,11 +82,9 @@ void helper_store_sdr1(CPUPPCState *env, target_ulong val)
 {
     PowerPCCPU *cpu = ppc_env_get_cpu(env);
 
-    if (!env->external_htab) {
-        if (env->spr[SPR_SDR1] != val) {
-            ppc_store_sdr1(env, val);
-            tlb_flush(CPU(cpu));
-        }
+    if (env->spr[SPR_SDR1] != val) {
+        ppc_store_sdr1(env, val);
+        tlb_flush(CPU(cpu));
     }
 }