target-microblaze: mmu: Add a configurable output address mask

Add a configurable output address mask, used to mimic the
configurable physical address bit width.
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.c

@@ -128,6 +128,7 @@ static void mb_cpu_reset(CPUState *s)
     env->mmu.c_mmu = 3;
     env->mmu.c_mmu_tlb_access = 3;
     env->mmu.c_mmu_zones = 16;
+    env->mmu.c_addr_mask = MAKE_64BIT_MASK(0, cpu->cfg.addr_size);
 #endif
 }
 

target/microblaze/mmu.c

@@ -164,6 +164,7 @@ unsigned int mmu_translate(struct microblaze_mmu *mmu,
             tlb_rpn = d & TLB_RPN_MASK;
 
             lu->vaddr = tlb_tag;
+            lu->paddr = tlb_rpn & mmu->c_addr_mask;
             lu->paddr = tlb_rpn;
             lu->size = tlb_size;
             lu->err = ERR_HIT;

target/microblaze/mmu.h

@@ -72,6 +72,7 @@ struct microblaze_mmu
     int c_mmu;
     int c_mmu_tlb_access;
     int c_mmu_zones;
+    uint64_t c_addr_mask; /* Mask to apply to physical addresses.  */
 };
 
 struct microblaze_mmu_lookup