target-microblaze: Consolidate MMU enabled checks

Consolidate MMU enabled checks to cpu_mmu_index().
No functional changes.
Suggested-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NAlistair Francis <alistair.francis@wdc.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>

target/microblaze/cpu.h

@@ -360,8 +360,10 @@ int cpu_mb_signal_handler(int host_signum, void *pinfo,
 
 static inline int cpu_mmu_index (CPUMBState *env, bool ifetch)
 {
+    MicroBlazeCPU *cpu = mb_env_get_cpu(env);
+
     /* Are we in nommu mode?.  */
-    if (!(env->sregs[SR_MSR] & MSR_VM)) {
+    if (!(env->sregs[SR_MSR] & MSR_VM) || !cpu->cfg.use_mmu) {
         return MMU_NOMMU_IDX;
     }
 

target/microblaze/helper.c

@@ -58,8 +58,7 @@ int mb_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
     int prot;
 
     /* Translate if the MMU is available and enabled.  */
-    if (cpu->cfg.use_mmu && (env->sregs[SR_MSR] & MSR_VM)
-        && mmu_idx != MMU_NOMMU_IDX) {
+    if (mmu_idx != MMU_NOMMU_IDX) {
         uint32_t vaddr, paddr;
         struct microblaze_mmu_lookup lu;
 
@@ -270,9 +269,10 @@ hwaddr mb_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
     CPUMBState *env = &cpu->env;
     target_ulong vaddr, paddr = 0;
     struct microblaze_mmu_lookup lu;
+    int mmu_idx = cpu_mmu_index(env, false);
     unsigned int hit;
 
-    if (env->sregs[SR_MSR] & MSR_VM) {
+    if (mmu_idx != MMU_NOMMU_IDX) {
         hit = mmu_translate(&env->mmu, &lu, addr, 0, 0);
         if (hit) {
             vaddr = addr & TARGET_PAGE_MASK;