target/mips: Add CP0 PWBase register

Add PWBase register (CP0 Register 5, Select 5).

The PWBase register contains the Page Table Base virtual address.

This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1.

Reviewed-by: Aleksandar Markovic <[email protected]>
Signed-off-by: Yongbok Kim <[email protected]>
Signed-off-by: Aleksandar Markovic <[email protected]>

diff --git a/target/mips/cpu.h b/target/mips/cpu.h
index 953643b037d71ec4b72bb2f8ff8ff8d3cb063210..9cbde99edd18dc13e5ef95bf9ba5857bd10a65f9 100644 (file)
--- a/target/mips/cpu.h
+++ b/target/mips/cpu.h
@@ -416,6 +416,7 @@ struct CPUMIPSState {
 #define CP0SC2_XR       56
 #define CP0SC2_XR_MASK  (0xFFULL << CP0SC2_XR)
 #define CP0SC2_MASK     (CP0SC_1GMASK | (CP0SC_1GMASK << 16) | CP0SC2_XR_MASK)
+    target_ulong CP0_PWBase;
 /*
  * CP0 Register 6
  */

diff --git a/target/mips/machine.c b/target/mips/machine.c
index 5ba78acd6d4dce7c1b7bc04b655bd5373d2fcc36..3592bb72e394cb45cd3a9ea37fc4605470797dd1 100644 (file)
--- a/target/mips/machine.c
+++ b/target/mips/machine.c
@@ -212,8 +212,8 @@ const VMStateDescription vmstate_tlb = {
 
 const VMStateDescription vmstate_mips_cpu = {
     .name = "cpu",
-    .version_id = 11,
-    .minimum_version_id = 11,
+    .version_id = 12,
+    .minimum_version_id = 12,
     .post_load = cpu_post_load,
     .fields = (VMStateField[]) {
         /* Active TC */
@@ -256,6 +256,7 @@ const VMStateDescription vmstate_mips_cpu = {
         VMSTATE_UINTTL(env.CP0_SegCtl0, MIPSCPU),
         VMSTATE_UINTTL(env.CP0_SegCtl1, MIPSCPU),
         VMSTATE_UINTTL(env.CP0_SegCtl2, MIPSCPU),
+        VMSTATE_UINTTL(env.CP0_PWBase, MIPSCPU),
         VMSTATE_INT32(env.CP0_Wired, MIPSCPU),
         VMSTATE_INT32(env.CP0_SRSConf0, MIPSCPU),
         VMSTATE_INT32(env.CP0_SRSConf1, MIPSCPU),

diff --git a/target/mips/translate.c b/target/mips/translate.c
index e26d54ac8cf3557d91dfe8cf731fb579cf42ac12..0896dccee3b4dc26e0ca79e11e1faab1df28dc0a 100644 (file)
--- a/target/mips/translate.c
+++ b/target/mips/translate.c
@@ -2478,6 +2478,19 @@ static inline void check_xnp(DisasContext *ctx)
     }
 }
 
+#ifndef CONFIG_USER_ONLY
+/*
+ * This code generates a "reserved instruction" exception if the
+ * Config3 PW bit is NOT set.
+ */
+static inline void check_pw(DisasContext *ctx)
+{
+    if (unlikely(!(ctx->CP0_Config3 & (1 << CP0C3_PW)))) {
+        generate_exception_end(ctx, EXCP_RI);
+    }
+}
+#endif
+
 /*
  * This code generates a "reserved instruction" exception if the
  * Config3 MT bit is NOT set.
@@ -6088,6 +6101,11 @@ static void gen_mfc0(DisasContext *ctx, TCGv arg, int reg, int sel)
             tcg_gen_ext32s_tl(arg, arg);
             rn = "SegCtl2";
             break;
+        case 5:
+            check_pw(ctx);
+            gen_mfc0_load32(arg, offsetof(CPUMIPSState, CP0_PWBase));
+            rn = "PWBase";
+            break;
         default:
             goto cp0_unimplemented;
         }
@@ -6789,6 +6807,11 @@ static void gen_mtc0(DisasContext *ctx, TCGv arg, int reg, int sel)
             gen_helper_mtc0_segctl2(cpu_env, arg);
             rn = "SegCtl2";
             break;
+        case 5:
+            check_pw(ctx);
+            gen_mtc0_store32(arg, offsetof(CPUMIPSState, CP0_PWBase));
+            rn = "PWBase";
+            break;
         default:
             goto cp0_unimplemented;
         }
@@ -7499,6 +7522,11 @@ static void gen_dmfc0(DisasContext *ctx, TCGv arg, int reg, int sel)
             tcg_gen_ld_tl(arg, cpu_env, offsetof(CPUMIPSState, CP0_SegCtl2));
             rn = "SegCtl2";
             break;
+        case 5:
+            check_pw(ctx);
+            tcg_gen_ld_tl(arg, cpu_env, offsetof(CPUMIPSState, CP0_PWBase));
+            rn = "PWBase";
+            break;
         default:
             goto cp0_unimplemented;
         }
@@ -8182,6 +8210,11 @@ static void gen_dmtc0(DisasContext *ctx, TCGv arg, int reg, int sel)
             gen_helper_mtc0_segctl2(cpu_env, arg);
             rn = "SegCtl2";
             break;
+        case 5:
+            check_pw(ctx);
+            tcg_gen_st_tl(arg, cpu_env, offsetof(CPUMIPSState, CP0_PWBase));
+            rn = "PWBase";
+            break;
         default:
             goto cp0_unimplemented;
         }