[Qemu-devel] [PATCH v2] target-mips: add PC, XNP reg numbers to RDHWR

[Yongbok Kim]

Add Performance Counter (4) and XNP (5) register numbers to RDHWR.
Add check_hwrena() to simplify access control checkings.
Add RDHWR support to microMIPS R6.

Signed-off-by: Yongbok Kim <address@hidden>
---
 target-mips/cpu.h       |    1 +
 target-mips/helper.h    |    2 +
 target-mips/op_helper.c |   64 +++++++++++++++++++++++++---------------------
 target-mips/translate.c |   28 ++++++++++++++++++--
 4 files changed, 63 insertions(+), 32 deletions(-)

diff --git a/target-mips/cpu.h b/target-mips/cpu.h
index c68681d..fa919c1 100644
--- a/target-mips/cpu.h
+++ b/target-mips/cpu.h
@@ -469,6 +469,7 @@ struct CPUMIPSState {
 #define CP0C5_CV         29
 #define CP0C5_EVA        28
 #define CP0C5_MSAEn      27
+#define CP0C5_XNP        13
 #define CP0C5_UFE        9
 #define CP0C5_FRE        8
 #define CP0C5_SBRI       6
diff --git a/target-mips/helper.h b/target-mips/helper.h
index d8cc766..95b9149 100644
--- a/target-mips/helper.h
+++ b/target-mips/helper.h
@@ -358,6 +358,8 @@ DEF_HELPER_1(rdhwr_cpunum, tl, env)
 DEF_HELPER_1(rdhwr_synci_step, tl, env)
 DEF_HELPER_1(rdhwr_cc, tl, env)
 DEF_HELPER_1(rdhwr_ccres, tl, env)
+DEF_HELPER_1(rdhwr_performance, tl, env)
+DEF_HELPER_1(rdhwr_xnp, tl, env)
 DEF_HELPER_2(pmon, void, env, int)
 DEF_HELPER_1(wait, void, env)
 
diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c
index 6739fff..ff03465 100644
--- a/target-mips/op_helper.c
+++ b/target-mips/op_helper.c
@@ -1357,6 +1357,13 @@ void helper_mtc0_hwrena(CPUMIPSState *env, target_ulong 
arg1)
 {
     uint32_t mask = 0x0000000F;
 
+    if ((env->CP0_Config1 & (1 << CP0C1_PC)) &&
+            (env->insn_flags & ISA_MIPS32R6)) {
+        mask |= (1 << 4);
+    }
+    if (env->insn_flags & ISA_MIPS32R6) {
+        mask |= (1 << 5);
+    }
     if (env->CP0_Config3 & (1 << CP0C3_ULRI)) {
         mask |= (1 << 29);
 
@@ -2185,53 +2192,52 @@ void helper_deret(CPUMIPSState *env)
 }
 #endif /* !CONFIG_USER_ONLY */
 
-target_ulong helper_rdhwr_cpunum(CPUMIPSState *env)
+static inline void check_hwrena(CPUMIPSState *env, int reg)
 {
-    if ((env->hflags & MIPS_HFLAG_CP0) ||
-        (env->CP0_HWREna & (1 << 0)))
-        return env->CP0_EBase & 0x3ff;
-    else
-        do_raise_exception(env, EXCP_RI, GETPC());
+    if ((env->hflags & MIPS_HFLAG_CP0) || (env->CP0_HWREna & (1 << reg))) {
+        return;
+    }
+    do_raise_exception(env, EXCP_RI, GETPC());
+}
 
-    return 0;
+target_ulong helper_rdhwr_cpunum(CPUMIPSState *env)
+{
+    check_hwrena(env, 0);
+    return env->CP0_EBase & 0x3ff;
 }
 
 target_ulong helper_rdhwr_synci_step(CPUMIPSState *env)
 {
-    if ((env->hflags & MIPS_HFLAG_CP0) ||
-        (env->CP0_HWREna & (1 << 1)))
-        return env->SYNCI_Step;
-    else
-        do_raise_exception(env, EXCP_RI, GETPC());
-
-    return 0;
+    check_hwrena(env, 1);
+    return env->SYNCI_Step;
 }
 
 target_ulong helper_rdhwr_cc(CPUMIPSState *env)
 {
-    if ((env->hflags & MIPS_HFLAG_CP0) ||
-        (env->CP0_HWREna & (1 << 2))) {
+    check_hwrena(env, 2);
 #ifdef CONFIG_USER_ONLY
-        return env->CP0_Count;
+    return env->CP0_Count;
 #else
-        return (int32_t)cpu_mips_get_count(env);
+    return (int32_t)cpu_mips_get_count(env);
 #endif
-    } else {
-        do_raise_exception(env, EXCP_RI, GETPC());
-    }
-
-    return 0;
 }
 
 target_ulong helper_rdhwr_ccres(CPUMIPSState *env)
 {
-    if ((env->hflags & MIPS_HFLAG_CP0) ||
-        (env->CP0_HWREna & (1 << 3)))
-        return env->CCRes;
-    else
-        do_raise_exception(env, EXCP_RI, GETPC());
+    check_hwrena(env, 3);
+    return env->CCRes;
+}
 
-    return 0;
+target_ulong helper_rdhwr_performance(CPUMIPSState *env)
+{
+    check_hwrena(env, 4);
+    return env->CP0_Performance0;
+}
+
+target_ulong helper_rdhwr_xnp(CPUMIPSState *env)
+{
+    check_hwrena(env, 5);
+    return (env->CP0_Config5 >> CP0C5_XNP) & 1;
 }
 
 void helper_pmon(CPUMIPSState *env, int function)
diff --git a/target-mips/translate.c b/target-mips/translate.c
index df24d6b..9046c30 100644
--- a/target-mips/translate.c
+++ b/target-mips/translate.c
@@ -10334,7 +10334,7 @@ static void gen_flt3_arith (DisasContext *ctx, uint32_t 
opc,
     }
 }
 
-static void gen_rdhwr(DisasContext *ctx, int rt, int rd)
+static void gen_rdhwr(DisasContext *ctx, int rt, int rd, int sel)
 {
     TCGv t0;
 
@@ -10362,6 +10362,22 @@ static void gen_rdhwr(DisasContext *ctx, int rt, int 
rd)
         gen_helper_rdhwr_ccres(t0, cpu_env);
         gen_store_gpr(t0, rt);
         break;
+    case 4:
+        check_insn(ctx, ISA_MIPS32R6);
+        if (sel != 0) {
+            /* Performance counter registers are not implemented other than
+             * control register 0.
+             */
+            generate_exception(ctx, EXCP_RI);
+        }
+        gen_helper_rdhwr_performance(t0, cpu_env);
+        gen_store_gpr(t0, rt);
+        break;
+    case 5:
+        check_insn(ctx, ISA_MIPS32R6);
+        gen_helper_rdhwr_xnp(t0, cpu_env);
+        gen_store_gpr(t0, rt);
+        break;
     case 29:
 #if defined(CONFIG_USER_ONLY)
         tcg_gen_ld_tl(t0, cpu_env,
@@ -11980,6 +11996,7 @@ enum {
     ROTR = 0x3,
     SELEQZ = 0x5,
     SELNEZ = 0x6,
+    R6_RDHWR = 0x7,
 
     SLLV = 0x0,
     SRLV = 0x1,
@@ -12934,7 +12951,8 @@ static void gen_pool32axf (CPUMIPSState *env, 
DisasContext *ctx, int rt, int rs)
             gen_cl(ctx, mips32_op, rt, rs);
             break;
         case RDHWR:
-            gen_rdhwr(ctx, rt, rs);
+            check_insn_opc_removed(ctx, ISA_MIPS32R6);
+            gen_rdhwr(ctx, rt, rs, 0);
             break;
         case WSBH:
             gen_bshfl(ctx, OPC_WSBH, rs, rt);
@@ -13489,6 +13507,10 @@ static void decode_micromips32_opc(CPUMIPSState *env, 
DisasContext *ctx)
                 check_insn(ctx, ISA_MIPS32R6);
                 gen_cond_move(ctx, OPC_SELNEZ, rd, rs, rt);
                 break;
+            case R6_RDHWR:
+                check_insn(ctx, ISA_MIPS32R6);
+                gen_rdhwr(ctx, rt, rs, extract32(ctx->opcode, 11, 3));
+                break;
             default:
                 goto pool32a_invalid;
             }
@@ -17739,7 +17761,7 @@ static void decode_opc_special3(CPUMIPSState *env, 
DisasContext *ctx)
         break;
 #endif
     case OPC_RDHWR:
-        gen_rdhwr(ctx, rt, rd);
+        gen_rdhwr(ctx, rt, rd, extract32(ctx->opcode, 6, 3));
         break;
     case OPC_FORK:
         check_insn(ctx, ASE_MT);
-- 
1.7.1