target/riscv: Add additional xlen for address when MPRV=1

As specified in privilege spec:"When MPRV=1, load and store memory
addresses are treated as though the current XLEN were set to MPP’s
XLEN". So the xlen for address may be different from current xlen.

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230614032547.35895-2-liweiwei@iscas.ac.cn>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

target/riscv/cpu.h

@@ -500,6 +500,7 @@ FIELD(TB_FLAGS, ITRIGGER, 22, 1)
 /* Virtual mode enabled */
 FIELD(TB_FLAGS, VIRT_ENABLED, 23, 1)
 FIELD(TB_FLAGS, PRIV, 24, 2)
+FIELD(TB_FLAGS, AXL, 26, 2)
 
 #ifdef TARGET_RISCV32
 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
@@ -516,21 +517,28 @@ static inline const RISCVCPUConfig *riscv_cpu_cfg(CPURISCVState *env)
     return &env_archcpu(env)->cfg;
 }
 
-#if defined(TARGET_RISCV32)
-#define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
-#else
-static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
+#if !defined(CONFIG_USER_ONLY)
+static inline int cpu_address_mode(CPURISCVState *env)
+{
+    int mode = env->priv;
+
+    if (mode == PRV_M && get_field(env->mstatus, MSTATUS_MPRV)) {
+        mode = get_field(env->mstatus, MSTATUS_MPP);
+    }
+    return mode;
+}
+
+static inline RISCVMXL cpu_get_xl(CPURISCVState *env, target_ulong mode)
 {
     RISCVMXL xl = env->misa_mxl;
-#if !defined(CONFIG_USER_ONLY)
     /*
      * When emulating a 32-bit-only cpu, use RV32.
      * When emulating a 64-bit cpu, and MXL has been reduced to RV32,
      * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened
      * back to RV64 for lower privs.
      */
     if (xl != MXL_RV32) {
-        switch (env->priv) {
+        switch (mode) {
         case PRV_M:
             break;
         case PRV_U:
@@ -541,11 +549,38 @@ static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
             break;
         }
     }
-#endif
     return xl;
 }
 #endif
 
+#if defined(TARGET_RISCV32)
+#define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
+#else
+static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
+{
+#if !defined(CONFIG_USER_ONLY)
+    return cpu_get_xl(env, env->priv);
+#else
+    return env->misa_mxl;
+#endif
+}
+#endif
+
+#if defined(TARGET_RISCV32)
+#define cpu_address_xl(env)  ((void)(env), MXL_RV32)
+#else
+static inline RISCVMXL cpu_address_xl(CPURISCVState *env)
+{
+#ifdef CONFIG_USER_ONLY
+    return env->xl;
+#else
+    int mode = cpu_address_mode(env);
+
+    return cpu_get_xl(env, mode);
+#endif
+}
+#endif
+
 static inline int riscv_cpu_xlen(CPURISCVState *env)
 {
     return 16 << env->xl;

target/riscv/cpu_helper.c

@@ -135,6 +135,7 @@ void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc,
     flags = FIELD_DP32(flags, TB_FLAGS, FS, fs);
     flags = FIELD_DP32(flags, TB_FLAGS, VS, vs);
     flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl);
+    flags = FIELD_DP32(flags, TB_FLAGS, AXL, cpu_address_xl(env));
     if (env->cur_pmmask != 0) {
         flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1);
     }

target/riscv/translate.c

@@ -64,6 +64,7 @@ typedef struct DisasContext {
     target_ulong priv_ver;
     RISCVMXL misa_mxl_max;
     RISCVMXL xl;
+    RISCVMXL address_xl;
     uint32_t misa_ext;
     uint32_t opcode;
     RISCVExtStatus mstatus_fs;
@@ -129,6 +130,14 @@ static inline bool has_ext(DisasContext *ctx, uint32_t ext)
 #define get_xl(ctx)    ((ctx)->xl)
 #endif
 
+#ifdef TARGET_RISCV32
+#define get_address_xl(ctx)    MXL_RV32
+#elif defined(CONFIG_USER_ONLY)
+#define get_address_xl(ctx)    MXL_RV64
+#else
+#define get_address_xl(ctx)    ((ctx)->address_xl)
+#endif
+
 /* The word size for this machine mode. */
 static inline int __attribute__((unused)) get_xlen(DisasContext *ctx)
 {
@@ -575,12 +584,13 @@ static TCGv get_address(DisasContext *ctx, int rs1, int imm)
     tcg_gen_addi_tl(addr, src1, imm);
     if (ctx->pm_mask_enabled) {
         tcg_gen_andc_tl(addr, addr, pm_mask);
-    } else if (get_xl(ctx) == MXL_RV32) {
+    } else if (get_address_xl(ctx) == MXL_RV32) {
         tcg_gen_ext32u_tl(addr, addr);
     }
     if (ctx->pm_base_enabled) {
         tcg_gen_or_tl(addr, addr, pm_base);
     }
+
     return addr;
 }
 
@@ -1177,6 +1187,7 @@ static void riscv_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->vl_eq_vlmax = FIELD_EX32(tb_flags, TB_FLAGS, VL_EQ_VLMAX);
     ctx->misa_mxl_max = env->misa_mxl_max;
     ctx->xl = FIELD_EX32(tb_flags, TB_FLAGS, XL);
+    ctx->address_xl = FIELD_EX32(tb_flags, TB_FLAGS, AXL);
     ctx->cs = cs;
     ctx->pm_mask_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_MASK_ENABLED);
     ctx->pm_base_enabled = FIELD_EX32(tb_flags, TB_FLAGS, PM_BASE_ENABLED);