From 4eb5a2908392b33efb8ac73667a7b912fd913fc6 Mon Sep 17 00:00:00 2001
From: ths <ths>
Date: Sun, 26 Aug 2007 17:37:23 +0000
Subject: [PATCH] Disable 64-bit instructions on 32-bit CPU, by Aurelien Jarno.

---
 target-mips/helper.c         |  9 ++++++---
 target-mips/op.c             | 15 +++++++++------
 target-mips/translate.c      | 16 ++++++++--------
 target-mips/translate_init.c | 16 +++++++++-------
 4 files changed, 32 insertions(+), 24 deletions(-)

diff --git a/target-mips/helper.c b/target-mips/helper.c
index c1a7792f72..1c83704705 100644
--- a/target-mips/helper.c
+++ b/target-mips/helper.c
@@ -369,7 +369,8 @@ void do_interrupt (CPUState *env)
         }
     enter_debug_mode:
         env->hflags |= MIPS_HFLAG_DM;
-        env->hflags |= MIPS_HFLAG_64;
+        if ((env->CP0_Config0 & (0x3 << CP0C0_AT)))
+            env->hflags |= MIPS_HFLAG_64;
         env->hflags &= ~MIPS_HFLAG_UM;
         /* EJTAG probe trap enable is not implemented... */
         if (!(env->CP0_Status & (1 << CP0St_EXL)))
@@ -395,7 +396,8 @@ void do_interrupt (CPUState *env)
             env->CP0_ErrorEPC = env->PC;
         }
         env->CP0_Status |= (1 << CP0St_ERL) | (1 << CP0St_BEV);
-        env->hflags |= MIPS_HFLAG_64;
+        if ((env->CP0_Config0 & (0x3 << CP0C0_AT)))
+            env->hflags |= MIPS_HFLAG_64;
         env->hflags &= ~MIPS_HFLAG_UM;
         if (!(env->CP0_Status & (1 << CP0St_EXL)))
             env->CP0_Cause &= ~(1 << CP0Ca_BD);
@@ -494,7 +496,8 @@ void do_interrupt (CPUState *env)
                 env->CP0_Cause &= ~(1 << CP0Ca_BD);
             }
             env->CP0_Status |= (1 << CP0St_EXL);
-            env->hflags |= MIPS_HFLAG_64;
+            if ((env->CP0_Config0 & (0x3 << CP0C0_AT)))
+                env->hflags |= MIPS_HFLAG_64;
             env->hflags &= ~MIPS_HFLAG_UM;
         }
         env->hflags &= ~MIPS_HFLAG_BMASK;
diff --git a/target-mips/op.c b/target-mips/op.c
index 4aa63e3463..12498d0335 100644
--- a/target-mips/op.c
+++ b/target-mips/op.c
@@ -1358,9 +1358,10 @@ void op_mtc0_status (void)
         (val & (1 << CP0St_UM)))
         env->hflags |= MIPS_HFLAG_UM;
 #ifdef TARGET_MIPS64
-    if ((env->hflags & MIPS_HFLAG_UM) &&
+    if (!(env->CP0_Config0 & (0x3 << CP0C0_AT)) ||
+        ((env->hflags & MIPS_HFLAG_UM) &&
         !(val & (1 << CP0St_PX)) &&
-        !(val & (1 << CP0St_UX)))
+        !(val & (1 << CP0St_UX))))
         env->hflags &= ~MIPS_HFLAG_64;
 #endif
     if (val & (1 << CP0St_CU1))
@@ -2318,9 +2319,10 @@ void op_eret (void)
         (env->CP0_Status & (1 << CP0St_UM)))
         env->hflags |= MIPS_HFLAG_UM;
 #ifdef TARGET_MIPS64
-    if ((env->hflags & MIPS_HFLAG_UM) &&
+    if (!(env->CP0_Config0 & (0x3 << CP0C0_AT)) ||
+        ((env->hflags & MIPS_HFLAG_UM) &&
         !(env->CP0_Status & (1 << CP0St_PX)) &&
-        !(env->CP0_Status & (1 << CP0St_UX)))
+        !(env->CP0_Status & (1 << CP0St_UX))))
         env->hflags &= ~MIPS_HFLAG_64;
 #endif
     if (loglevel & CPU_LOG_EXEC)
@@ -2341,9 +2343,10 @@ void op_deret (void)
         (env->CP0_Status & (1 << CP0St_UM)))
         env->hflags |= MIPS_HFLAG_UM;
 #ifdef TARGET_MIPS64
-    if ((env->hflags & MIPS_HFLAG_UM) &&
+    if (!(env->CP0_Config0 & (0x3 << CP0C0_AT)) ||
+        ((env->hflags & MIPS_HFLAG_UM) &&
         !(env->CP0_Status & (1 << CP0St_PX)) &&
-        !(env->CP0_Status & (1 << CP0St_UX)))
+        !(env->CP0_Status & (1 << CP0St_UX))))
         env->hflags &= ~MIPS_HFLAG_64;
 #endif
     if (loglevel & CPU_LOG_EXEC)
diff --git a/target-mips/translate.c b/target-mips/translate.c
index 7f5141c33c..07dca14595 100644
--- a/target-mips/translate.c
+++ b/target-mips/translate.c
@@ -2225,6 +2225,8 @@ static void gen_mfc0 (CPUState *env, DisasContext *ctx, int reg, int sel)
         switch (sel) {
         case 0:
 #ifdef TARGET_MIPS64
+	    if (!(ctx->hflags & MIPS_HFLAG_64))
+	        goto die;
             gen_op_mfc0_xcontext();
             rn = "XContext";
             break;
@@ -2781,6 +2783,8 @@ static void gen_mtc0 (CPUState *env, DisasContext *ctx, int reg, int sel)
         switch (sel) {
         case 0:
 #ifdef TARGET_MIPS64
+	    if (!(ctx->hflags & MIPS_HFLAG_64))
+	        goto die;
             gen_op_mtc0_xcontext();
             rn = "XContext";
             break;
@@ -3331,11 +3335,9 @@ static void gen_dmfc0 (CPUState *env, DisasContext *ctx, int reg, int sel)
     case 20:
         switch (sel) {
         case 0:
-#ifdef TARGET_MIPS64
             gen_op_dmfc0_xcontext();
             rn = "XContext";
             break;
-#endif
         default:
             goto die;
         }
@@ -3878,11 +3880,9 @@ static void gen_dmtc0 (CPUState *env, DisasContext *ctx, int reg, int sel)
     case 20:
         switch (sel) {
         case 0:
-#ifdef TARGET_MIPS64
             gen_op_mtc0_xcontext();
             rn = "XContext";
             break;
-#endif
         default:
             goto die;
         }
@@ -4107,6 +4107,8 @@ static void gen_cp0 (CPUState *env, DisasContext *ctx, uint32_t opc, int rt, int
         break;
 #ifdef TARGET_MIPS64
     case OPC_DMFC0:
+        if (!(ctx->hflags & MIPS_HFLAG_64))
+            generate_exception(ctx, EXCP_RI);
         if (rt == 0) {
             /* Treat as NOP */
             return;
@@ -4116,6 +4118,8 @@ static void gen_cp0 (CPUState *env, DisasContext *ctx, uint32_t opc, int rt, int
         opn = "dmfc0";
         break;
     case OPC_DMTC0:
+        if (!(ctx->hflags & MIPS_HFLAG_64))
+            generate_exception(ctx, EXCP_RI);
         GEN_LOAD_REG_TN(T0, rt);
         gen_dmtc0(env,ctx, rd, ctx->opcode & 0x7);
         opn = "dmtc0";
@@ -6183,11 +6187,7 @@ void cpu_reset (CPUMIPSState *env)
     } else {
         env->CP0_ErrorEPC = env->PC;
     }
-#ifdef TARGET_MIPS64
-    env->hflags = MIPS_HFLAG_64;
-#else
     env->hflags = 0;
-#endif
     env->PC = (int32_t)0xBFC00000;
     env->CP0_Wired = 0;
     /* SMP not implemented */
diff --git a/target-mips/translate_init.c b/target-mips/translate_init.c
index 85d5032a2b..d327312e55 100644
--- a/target-mips/translate_init.c
+++ b/target-mips/translate_init.c
@@ -86,7 +86,6 @@ static mips_def_t mips_defs[] =
         .SYNCI_Step = 32,
         .CCRes = 2,
         .Status_rw_bitmask = 0x3278FF17,
-        .SEGBITS = 32,
     },
     {
         .name = "4KEcR1",
@@ -100,7 +99,6 @@ static mips_def_t mips_defs[] =
         .SYNCI_Step = 32,
         .CCRes = 2,
         .Status_rw_bitmask = 0x3278FF17,
-        .SEGBITS = 32,
     },
     {
         .name = "4KEc",
@@ -114,7 +112,6 @@ static mips_def_t mips_defs[] =
         .SYNCI_Step = 32,
         .CCRes = 2,
         .Status_rw_bitmask = 0x3278FF17,
-        .SEGBITS = 32,
     },
     {
         .name = "24Kc",
@@ -128,7 +125,6 @@ static mips_def_t mips_defs[] =
         .SYNCI_Step = 32,
         .CCRes = 2,
         .Status_rw_bitmask = 0x3278FF17,
-        .SEGBITS = 32,
     },
     {
         .name = "24Kf",
@@ -144,7 +140,6 @@ static mips_def_t mips_defs[] =
         .Status_rw_bitmask = 0x3678FF17,
         .CP1_fcr0 = (1 << FCR0_F64) | (1 << FCR0_L) | (1 << FCR0_W) |
                     (1 << FCR0_D) | (1 << FCR0_S) | (0x93 << FCR0_PRID),
-        .SEGBITS = 32,
     },
 #ifdef TARGET_MIPS64
     {
@@ -293,8 +288,15 @@ int cpu_mips_register (CPUMIPSState *env, mips_def_t *def)
     env->Status_rw_bitmask = def->Status_rw_bitmask;
     env->fcr0 = def->CP1_fcr0;
 #ifdef TARGET_MIPS64
-    env->SEGBITS = def->SEGBITS;
-    env->SEGMask = (3ULL << 62) | ((1ULL << def->SEGBITS) - 1);
+    if ((env->CP0_Config0 & (0x3 << CP0C0_AT)))
+    {
+        env->hflags |= MIPS_HFLAG_64;
+        env->SEGBITS = def->SEGBITS;
+        env->SEGMask = (3ULL << 62) | ((1ULL << def->SEGBITS) - 1);
+    } else {
+        env->SEGBITS = 32;
+        env->SEGMask = 0xFFFFFFFF;
+    }
 #endif
 #ifdef CONFIG_USER_ONLY
     if (env->CP0_Config1 & (1 << CP0C1_FP))
-- 
2.11.4.GIT