[Qemu-devel] [PULL 05/34] target-mips: update PageGrain and m{t, f}c0 EntryLo{0, 1}

[Leon Alrae <leon.alrae@imgtec.com>]

PageGrain needs rw bitmask which differs between MIPS architectures.
In pre-R6 if RIXI is supported, PageGrain.XIE and PageGrain.RIE are writeable,
whereas in R6 they are read-only 1.

On MIPS64 mtc0 instruction left shifts bits 31:30 for MIPS32 backward
compatiblity, therefore there are separate mtc0 and dmtc0 helpers.

Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Yongbok Kim <yongbok.kim@imgtec.com>
---
 target-mips/cpu.h            |  4 ++++
 target-mips/helper.h         |  5 +++++
 target-mips/op_helper.c      | 25 ++++++++++++++++++++++---
 target-mips/translate.c      | 26 ++++++++++++++++++++++++--
 target-mips/translate_init.c |  2 ++
 5 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/target-mips/cpu.h b/target-mips/cpu.h
index 13f3a48..38f90f2 100644
--- a/target-mips/cpu.h
+++ b/target-mips/cpu.h
@@ -243,7 +243,10 @@ struct CPUMIPSState {
     target_ulong CP0_Context;
     target_ulong CP0_KScratch[MIPS_KSCRATCH_NUM];
     int32_t CP0_PageMask;
+    int32_t CP0_PageGrain_rw_bitmask;
     int32_t CP0_PageGrain;
+#define CP0PG_RIE 31
+#define CP0PG_XIE 30
     int32_t CP0_Wired;
     int32_t CP0_SRSConf0_rw_bitmask;
     int32_t CP0_SRSConf0;
@@ -377,6 +380,7 @@ struct CPUMIPSState {
 #define CP0C3_M    31
 #define CP0C3_ISA_ON_EXC 16
 #define CP0C3_ULRI 13
+#define CP0C3_RXI  12
 #define CP0C3_DSPP 10
 #define CP0C3_LPA  7
 #define CP0C3_VEIC 6
diff --git a/target-mips/helper.h b/target-mips/helper.h
index a127db5..e7e0c8c 100644
--- a/target-mips/helper.h
+++ b/target-mips/helper.h
@@ -152,6 +152,11 @@ DEF_HELPER_2(mtc0_datalo, void, env, tl)
 DEF_HELPER_2(mtc0_taghi, void, env, tl)
 DEF_HELPER_2(mtc0_datahi, void, env, tl)
 
+#if defined(TARGET_MIPS64)
+DEF_HELPER_2(dmtc0_entrylo0, void, env, i64)
+DEF_HELPER_2(dmtc0_entrylo1, void, env, i64)
+#endif
+
 /* MIPS MT functions */
 DEF_HELPER_2(mftgpr, tl, env, i32)
 DEF_HELPER_2(mftlo, tl, env, i32)
diff --git a/target-mips/op_helper.c b/target-mips/op_helper.c
index 582c84e..024a6a2 100644
--- a/target-mips/op_helper.c
+++ b/target-mips/op_helper.c
@@ -1099,9 +1099,18 @@ void helper_mtc0_entrylo0(CPUMIPSState *env, target_ulong arg1)
 {
     /* Large physaddr (PABITS) not implemented */
     /* 1k pages not implemented */
-    env->CP0_EntryLo0 = arg1 & 0x3FFFFFFF;
+    target_ulong rxi = arg1 & (env->CP0_PageGrain & (3u << CP0PG_XIE));
+    env->CP0_EntryLo0 = (arg1 & 0x3FFFFFFF) | (rxi << (CP0EnLo_XI - 30));
 }
 
+#if defined(TARGET_MIPS64)
+void helper_dmtc0_entrylo0(CPUMIPSState *env, uint64_t arg1)
+{
+    uint64_t rxi = arg1 & ((env->CP0_PageGrain & (3ull << CP0PG_XIE)) << 32);
+    env->CP0_EntryLo0 = (arg1 & 0x3FFFFFFF) | rxi;
+}
+#endif
+
 void helper_mtc0_tcstatus(CPUMIPSState *env, target_ulong arg1)
 {
     uint32_t mask = env->CP0_TCStatus_rw_bitmask;
@@ -1266,9 +1275,18 @@ void helper_mtc0_entrylo1(CPUMIPSState *env, target_ulong arg1)
 {
     /* Large physaddr (PABITS) not implemented */
     /* 1k pages not implemented */
-    env->CP0_EntryLo1 = arg1 & 0x3FFFFFFF;
+    target_ulong rxi = arg1 & (env->CP0_PageGrain & (3u << CP0PG_XIE));
+    env->CP0_EntryLo1 = (arg1 & 0x3FFFFFFF) | (rxi << (CP0EnLo_XI - 30));
 }
 
+#if defined(TARGET_MIPS64)
+void helper_dmtc0_entrylo1(CPUMIPSState *env, uint64_t arg1)
+{
+    uint64_t rxi = arg1 & ((env->CP0_PageGrain & (3ull << CP0PG_XIE)) << 32);
+    env->CP0_EntryLo1 = (arg1 & 0x3FFFFFFF) | rxi;
+}
+#endif
+
 void helper_mtc0_context(CPUMIPSState *env, target_ulong arg1)
 {
     env->CP0_Context = (env->CP0_Context & 0x007FFFFF) | (arg1 & ~0x007FFFFF);
@@ -1285,7 +1303,8 @@ void helper_mtc0_pagegrain(CPUMIPSState *env, target_ulong arg1)
     /* SmartMIPS not implemented */
     /* Large physaddr (PABITS) not implemented */
     /* 1k pages not implemented */
-    env->CP0_PageGrain = 0;
+    env->CP0_PageGrain = (arg1 & env->CP0_PageGrain_rw_bitmask) |
+                         (env->CP0_PageGrain & ~env->CP0_PageGrain_rw_bitmask);
 }
 
 void helper_mtc0_wired(CPUMIPSState *env, target_ulong arg1)
diff --git a/target-mips/translate.c b/target-mips/translate.c
index 167f9bc..e8933a9 100644
--- a/target-mips/translate.c
+++ b/target-mips/translate.c
@@ -1171,6 +1171,7 @@ typedef struct DisasContext {
     target_ulong btarget;
     bool ulri;
     int kscrexist;
+    bool rxi;
 } DisasContext;
 
 enum {
@@ -4659,6 +4660,15 @@ static void gen_mfc0(DisasContext *ctx, TCGv arg, int reg, int sel)
         switch (sel) {
         case 0:
             tcg_gen_ld_tl(arg, cpu_env, offsetof(CPUMIPSState, CP0_EntryLo0));
+#if defined(TARGET_MIPS64)
+            if (ctx->rxi) {
+                TCGv tmp = tcg_temp_new();
+                tcg_gen_andi_tl(tmp, arg, (3ull << 62));
+                tcg_gen_shri_tl(tmp, tmp, 32);
+                tcg_gen_or_tl(arg, arg, tmp);
+                tcg_temp_free(tmp);
+            }
+#endif
             tcg_gen_ext32s_tl(arg, arg);
             rn = "EntryLo0";
             break;
@@ -4705,6 +4715,15 @@ static void gen_mfc0(DisasContext *ctx, TCGv arg, int reg, int sel)
         switch (sel) {
         case 0:
             tcg_gen_ld_tl(arg, cpu_env, offsetof(CPUMIPSState, CP0_EntryLo1));
+#if defined(TARGET_MIPS64)
+            if (ctx->rxi) {
+                TCGv tmp = tcg_temp_new();
+                tcg_gen_andi_tl(tmp, arg, (3ull << 62));
+                tcg_gen_shri_tl(tmp, tmp, 32);
+                tcg_gen_or_tl(arg, arg, tmp);
+                tcg_temp_free(tmp);
+            }
+#endif
             tcg_gen_ext32s_tl(arg, arg);
             rn = "EntryLo1";
             break;
@@ -6480,7 +6499,7 @@ static void gen_dmtc0(DisasContext *ctx, TCGv arg, int reg, int sel)
     case 2:
         switch (sel) {
         case 0:
-            gen_helper_mtc0_entrylo0(cpu_env, arg);
+            gen_helper_dmtc0_entrylo0(cpu_env, arg);
             rn = "EntryLo0";
             break;
         case 1:
@@ -6525,7 +6544,7 @@ static void gen_dmtc0(DisasContext *ctx, TCGv arg, int reg, int sel)
     case 3:
         switch (sel) {
         case 0:
-            gen_helper_mtc0_entrylo1(cpu_env, arg);
+            gen_helper_dmtc0_entrylo1(cpu_env, arg);
             rn = "EntryLo1";
             break;
         default:
@@ -17458,6 +17477,7 @@ gen_intermediate_code_internal(MIPSCPU *cpu, TranslationBlock *tb,
     ctx.tb = tb;
     ctx.bstate = BS_NONE;
     ctx.kscrexist = (env->CP0_Config4 >> CP0C4_KScrExist) & 0xff;
+    ctx.rxi = (env->CP0_Config3 >> CP0C3_RXI) & 1;
     /* Restore delay slot state from the tb context.  */
     ctx.hflags = (uint32_t)tb->flags; /* FIXME: maybe use 64 bits here? */
     ctx.ulri = env->CP0_Config3 & (1 << CP0C3_ULRI);
@@ -17840,6 +17860,8 @@ void cpu_state_reset(CPUMIPSState *env)
     env->CP0_SRSConf3 = env->cpu_model->CP0_SRSConf3;
     env->CP0_SRSConf4_rw_bitmask = env->cpu_model->CP0_SRSConf4_rw_bitmask;
     env->CP0_SRSConf4 = env->cpu_model->CP0_SRSConf4;
+    env->CP0_PageGrain_rw_bitmask = env->cpu_model->CP0_PageGrain_rw_bitmask;
+    env->CP0_PageGrain = env->cpu_model->CP0_PageGrain;
     env->active_fpu.fcr0 = env->cpu_model->CP1_fcr0;
     env->insn_flags = env->cpu_model->insn_flags;
 
diff --git a/target-mips/translate_init.c b/target-mips/translate_init.c
index 67b7837..779afff 100644
--- a/target-mips/translate_init.c
+++ b/target-mips/translate_init.c
@@ -96,6 +96,8 @@ struct mips_def_t {
     int32_t CP0_SRSConf3;
     int32_t CP0_SRSConf4_rw_bitmask;
     int32_t CP0_SRSConf4;
+    int32_t CP0_PageGrain_rw_bitmask;
+    int32_t CP0_PageGrain;
     int insn_flags;
     enum mips_mmu_types mmu_type;
 };
-- 
2.1.0