[PATCH v4 1/2] target/loongarch: Adjust the layout of hardware flags bit fields

[Rui Wang <wangrui@loongson.cn>]

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Rui Wang <wangrui@loongson.cn>
---
 target/loongarch/cpu.h                        | 27 ++++++++++++-------
 .../insn_trans/trans_privileged.c.inc         |  4 +--
 target/loongarch/tlb_helper.c                 |  4 +--
 target/loongarch/translate.c                  |  7 ++++-
 target/loongarch/translate.h                  |  3 ++-
 5 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index dbce176564..026cd6bb52 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -14,6 +14,7 @@
 #include "qemu/timer.h"
 #include "exec/memory.h"
 #include "hw/sysbus.h"
+#include "cpu-csr.h"
 
 #define IOCSRF_TEMP             0
 #define IOCSRF_NODECNT          1
@@ -373,24 +374,30 @@ struct LoongArchCPUClass {
  * 0 for kernel mode, 3 for user mode.
  * Define an extra index for DA(direct addressing) mode.
  */
-#define MMU_KERNEL_IDX   0
-#define MMU_USER_IDX     3
-#define MMU_DA_IDX       4
+#define MMU_PLV_KERNEL   0
+#define MMU_PLV_USER     3
+#define MMU_IDX_KERNEL   MMU_PLV_KERNEL
+#define MMU_IDX_USER     MMU_PLV_USER
+#define MMU_IDX_DA       4
 
 static inline int cpu_mmu_index(CPULoongArchState *env, bool ifetch)
 {
 #ifdef CONFIG_USER_ONLY
-    return MMU_USER_IDX;
+    return MMU_IDX_USER;
 #else
-    uint8_t pg = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PG);
-
-    if (!pg) {
-        return MMU_DA_IDX;
+    if (FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PG)) {
+        return FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PLV);
     }
-    return FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PLV);
+    return MMU_IDX_DA;
 #endif
 }
 
+/*
+ * LoongArch CPUs hardware flags.
+ */
+#define HW_FLAGS_PLV_MASK   R_CSR_CRMD_PLV_MASK  /* 0x03 */
+#define HW_FLAGS_CRMD_PG    R_CSR_CRMD_PG_MASK   /* 0x10 */
+
 static inline void cpu_get_tb_cpu_state(CPULoongArchState *env,
                                         target_ulong *pc,
                                         target_ulong *cs_base,
@@ -398,7 +405,7 @@ static inline void cpu_get_tb_cpu_state(CPULoongArchState *env,
 {
     *pc = env->pc;
     *cs_base = 0;
-    *flags = cpu_mmu_index(env, false);
+    *flags = env->CSR_CRMD & (R_CSR_CRMD_PLV_MASK | R_CSR_CRMD_PG_MASK);
 }
 
 void loongarch_cpu_list(void);
diff --git a/target/loongarch/insn_trans/trans_privileged.c.inc b/target/loongarch/insn_trans/trans_privileged.c.inc
index 9c4dcbfcfb..40f82becb0 100644
--- a/target/loongarch/insn_trans/trans_privileged.c.inc
+++ b/target/loongarch/insn_trans/trans_privileged.c.inc
@@ -159,7 +159,7 @@ static const CSRInfo csr_info[] = {
 
 static bool check_plv(DisasContext *ctx)
 {
-    if (ctx->base.tb->flags == MMU_USER_IDX) {
+    if (ctx->plv == MMU_PLV_USER) {
         generate_exception(ctx, EXCCODE_IPE);
         return true;
     }
@@ -335,7 +335,7 @@ TRANS(iocsrwr_d, gen_iocsrwr, gen_helper_iocsrwr_d)
 
 static void check_mmu_idx(DisasContext *ctx)
 {
-    if (ctx->mem_idx != MMU_DA_IDX) {
+    if (ctx->mem_idx != MMU_IDX_DA) {
         tcg_gen_movi_tl(cpu_pc, ctx->base.pc_next + 4);
         ctx->base.is_jmp = DISAS_EXIT;
     }
diff --git a/target/loongarch/tlb_helper.c b/target/loongarch/tlb_helper.c
index d2f8fb0c60..c6d1de50fe 100644
--- a/target/loongarch/tlb_helper.c
+++ b/target/loongarch/tlb_helper.c
@@ -170,8 +170,8 @@ static int get_physical_address(CPULoongArchState *env, hwaddr *physical,
                                 int *prot, target_ulong address,
                                 MMUAccessType access_type, int mmu_idx)
 {
-    int user_mode = mmu_idx == MMU_USER_IDX;
-    int kernel_mode = mmu_idx == MMU_KERNEL_IDX;
+    int user_mode = mmu_idx == MMU_IDX_USER;
+    int kernel_mode = mmu_idx == MMU_IDX_KERNEL;
     uint32_t plv, base_c, base_v;
     int64_t addr_high;
     uint8_t da = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, DA);
diff --git a/target/loongarch/translate.c b/target/loongarch/translate.c
index 6091772349..38ced69803 100644
--- a/target/loongarch/translate.c
+++ b/target/loongarch/translate.c
@@ -75,7 +75,12 @@ static void loongarch_tr_init_disas_context(DisasContextBase *dcbase,
     DisasContext *ctx = container_of(dcbase, DisasContext, base);
 
     ctx->page_start = ctx->base.pc_first & TARGET_PAGE_MASK;
-    ctx->mem_idx = ctx->base.tb->flags;
+    ctx->plv = ctx->base.tb->flags & HW_FLAGS_PLV_MASK;
+    if (ctx->base.tb->flags & HW_FLAGS_CRMD_PG) {
+        ctx->mem_idx = ctx->plv;
+    } else {
+        ctx->mem_idx = MMU_IDX_DA;
+    }
 
     /* Bound the number of insns to execute to those left on the page.  */
     bound = -(ctx->base.pc_first | TARGET_PAGE_MASK) / 4;
diff --git a/target/loongarch/translate.h b/target/loongarch/translate.h
index 9cc12512d1..6d2e382e8b 100644
--- a/target/loongarch/translate.h
+++ b/target/loongarch/translate.h
@@ -29,7 +29,8 @@ typedef struct DisasContext {
     DisasContextBase base;
     target_ulong page_start;
     uint32_t opcode;
-    int mem_idx;
+    uint16_t mem_idx;
+    uint16_t plv;
     TCGv zero;
     /* Space for 3 operands plus 1 extra for address computation. */
     TCGv temp[4];
-- 
2.38.1