target-sh4: MMU: separate execute and read/write permissions

On SH4, the ITLB and UTLB configurations are memory mapped, so loading
ITLB entries from UTLB has to be simulated correctly. For that the QEMU
TLB has to be handle the execute (ITLB) and read/write permissions
(UTLB) seperately.
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

target-sh4/helper.c

@@ -272,16 +272,6 @@ static int find_tlb_entry(CPUState * env, target_ulong address,
     return match;
 }
 
-static int same_tlb_entry_exists(const tlb_t * haystack, uint8_t nbtlb,
-				 const tlb_t * needle)
-{
-    int i;
-    for (i = 0; i < nbtlb; i++)
-        if (!memcmp(&haystack[i], needle, sizeof(tlb_t)))
-	    return 1;
-    return 0;
-}
-
 static void increment_urc(CPUState * env)
 {
     uint8_t urb, urc;
@@ -314,8 +304,7 @@ static int find_itlb_entry(CPUState * env, target_ulong address,
 	    n = itlb_replacement(env);
 	    ientry = &env->itlb[n];
 	    if (ientry->v) {
-		if (!same_tlb_entry_exists(env->utlb, UTLB_SIZE, ientry))
-		    tlb_flush_page(env, ientry->vpn << 10);
+                tlb_flush_page(env, ientry->vpn << 10);
 	    }
 	    *ientry = env->utlb[e];
 	    e = n;
@@ -362,7 +351,7 @@ static int get_mmu_address(CPUState * env, target_ulong * physical,
 	    if (!(env->sr & SR_MD) && !(matching->pr & 2))
 		n = MMU_ITLB_VIOLATION;
 	    else
-		*prot = PAGE_READ;
+		*prot = PAGE_EXEC;
 	}
     } else {
 	n = find_utlb_entry(env, address, use_asid);
@@ -418,14 +407,14 @@ static int get_physical_address(CPUState * env, target_ulong * physical,
 	} else {
 	    *physical = address;
 	}
-	*prot = PAGE_READ | PAGE_WRITE;
+	*prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
 	return MMU_OK;
     }
 
     /* If MMU is disabled, return the corresponding physical page */
     if (!env->mmucr & MMUCR_AT) {
 	*physical = address & 0x1FFFFFFF;
-	*prot = PAGE_READ | PAGE_WRITE;
+	*prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
 	return MMU_OK;
     }
 
@@ -506,9 +495,7 @@ void cpu_load_tlb(CPUSH4State * env)
     if (entry->v) {
         /* Overwriting valid entry in utlb. */
         target_ulong address = entry->vpn << 10;
-	if (!same_tlb_entry_exists(env->itlb, ITLB_SIZE, entry)) {
-	    tlb_flush_page(env, address);
-	}
+	tlb_flush_page(env, address);
     }
 
     /* Take values into cpu status from registers. */
@@ -623,9 +610,7 @@ void cpu_sh4_write_mmaped_utlb_addr(CPUSH4State *s, target_phys_addr_t addr,
 	if (entry->v) {
 	    /* Overwriting valid entry in utlb. */
             target_ulong address = entry->vpn << 10;
-	    if (!same_tlb_entry_exists(s->itlb, ITLB_SIZE, entry)) {
-	        tlb_flush_page(s, address);
-	    }
+	    tlb_flush_page(s, address);
 	}
 	entry->asid = asid;
 	entry->vpn = vpn;