[PULL 49/59] target/riscv: Fix the relationship of PBMTE/STCE fields between menvcfg and henvcfg

[Palmer Dabbelt]

From: Weiwei Li <liwei...@iscas.ac.cn>

henvcfg.PBMTE/STCE are read-only zero if menvcfg.PBMTE/STCE are zero.

Signed-off-by: Weiwei Li <liwei...@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqi...@iscas.ac.cn>
Reviewed-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
Message-ID: <20230224040852.37109-3-liwei...@iscas.ac.cn>
Signed-off-by: Palmer Dabbelt <pal...@rivosinc.com>
---
 target/riscv/csr.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index b20b00a9a7..b86c1aa6fa 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -1956,7 +1956,11 @@ static RISCVException read_henvcfg(CPURISCVState *env, 
int csrno,
         return ret;
     }
 
-    *val = env->henvcfg;
+    /*
+     * henvcfg.pbmte is read_only 0 when menvcfg.pbmte = 0
+     * henvcfg.stce is read_only 0 when menvcfg.stce = 0
+     */
+    *val = env->henvcfg & (~(HENVCFG_PBMTE | HENVCFG_STCE) | env->menvcfg);
     return RISCV_EXCP_NONE;
 }
 
@@ -1972,7 +1976,7 @@ static RISCVException write_henvcfg(CPURISCVState *env, 
int csrno,
     }
 
     if (riscv_cpu_mxl(env) == MXL_RV64) {
-        mask |= HENVCFG_PBMTE | HENVCFG_STCE;
+        mask |= env->menvcfg & (HENVCFG_PBMTE | HENVCFG_STCE);
     }
 
     env->henvcfg = (env->henvcfg & ~mask) | (val & mask);
@@ -1990,14 +1994,15 @@ static RISCVException read_henvcfgh(CPURISCVState *env, 
int csrno,
         return ret;
     }
 
-    *val = env->henvcfg >> 32;
+    *val = (env->henvcfg & (~(HENVCFG_PBMTE | HENVCFG_STCE) |
+                            env->menvcfg)) >> 32;
     return RISCV_EXCP_NONE;
 }
 
 static RISCVException write_henvcfgh(CPURISCVState *env, int csrno,
                                   target_ulong val)
 {
-    uint64_t mask = HENVCFG_PBMTE | HENVCFG_STCE;
+    uint64_t mask = env->menvcfg & (HENVCFG_PBMTE | HENVCFG_STCE);
     uint64_t valh = (uint64_t)val << 32;
     RISCVException ret;
 
-- 
2.39.2