[PATCH V3 5/6] target/riscv: Fix checks in hmode/hmode32

[Weiwei Li]

Add check for the implicit dependence between H and S

Csrs only existed in RV32 will not trigger virtual instruction fault
when not in RV32 based on section 8.6.1 of riscv-privileged spec
(draft-20220717)

Signed-off-by: Weiwei Li <liweiwei@iscas.ac.cn>
Signed-off-by: Junqiang Wang <wangjunqiang@iscas.ac.cn>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 target/riscv/cpu.c | 5 +++++
 target/riscv/csr.c | 9 ++-------
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index b8ce0959cb..455787a940 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -738,6 +738,11 @@ static void riscv_cpu_realize(DeviceState *dev, Error 
**errp)
             return;
         }
 
+        if (cpu->cfg.ext_h && !cpu->cfg.ext_s) {
+            error_setg(errp, "H extension implicitly requires S-mode");
+            return;
+        }
+
         if (cpu->cfg.ext_f && !cpu->cfg.ext_icsr) {
             error_setg(errp, "F extension requires Zicsr");
             return;
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index 5c69dc838c..cf15aa67b7 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -311,8 +311,7 @@ static int aia_smode32(CPURISCVState *env, int csrno)
 
 static RISCVException hmode(CPURISCVState *env, int csrno)
 {
-    if (riscv_has_ext(env, RVS) &&
-        riscv_has_ext(env, RVH)) {
+    if (riscv_has_ext(env, RVH)) {
         /* Hypervisor extension is supported */
         if ((env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
             env->priv == PRV_M) {
@@ -328,11 +327,7 @@ static RISCVException hmode(CPURISCVState *env, int csrno)
 static RISCVException hmode32(CPURISCVState *env, int csrno)
 {
     if (riscv_cpu_mxl(env) != MXL_RV32) {
-        if (!riscv_cpu_virt_enabled(env)) {
-            return RISCV_EXCP_ILLEGAL_INST;
-        } else {
-            return RISCV_EXCP_VIRT_INSTRUCTION_FAULT;
-        }
+        return RISCV_EXCP_ILLEGAL_INST;
     }
 
     return hmode(env, csrno);
-- 
2.17.1