The IBM PPE42 processor only supports real mode
addressing and does not distinguish between
problem and supervisor states. It also uses
the IR and DR MSR bits for other purposes.
Therefore, add a check for PPE42 when we update
hflags and cause it to ignore the IR and DR bits
when calculating MMU indexes.

Signed-off-by: Glenn Miles <milesg@linux.ibm.com>
---

Changes from v2:
  - Split MMU changes from v2 patch 1

 target/ppc/helper_regs.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/target/ppc/helper_regs.c b/target/ppc/helper_regs.c
index aaefeffa66..29158342d5 100644
--- a/target/ppc/helper_regs.c
+++ b/target/ppc/helper_regs.c
@@ -186,6 +186,10 @@ static uint32_t hreg_compute_hflags_value(CPUPPCState *env)
     if (env->spr[SPR_LPCR] & LPCR_HR) {
         hflags |= 1 << HFLAGS_HR;
     }
+    if (unlikely(ppc_flags & POWERPC_FLAG_PPE42)) {
+        /* PPE42 has a single address space and no problem state */
+        msr = 0;
+    }
 
 #ifndef CONFIG_USER_ONLY
     if (!env->has_hv_mode || (msr & (1ull << MSR_HV))) {
-- 
2.43.0