[PATCH 1/5] target/riscv: make mnstatus.MNPELP writable with Zicfilp

Zicfilp adds MNPELP to mnstatus, and MNRET consumes it when restoring ELP.
Include the field in write_mnstatus() when Zicfilp is implemented.
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/4222

Signed-off-by: wangyang <[email protected]>
---
 target/riscv/tcg/csr.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/target/riscv/tcg/csr.c b/target/riscv/tcg/csr.c
index 36f2004..5ffd858 100644
--- a/target/riscv/tcg/csr.c
+++ b/target/riscv/tcg/csr.c
@@ -5563,6 +5563,10 @@ static RISCVException write_mnstatus(CPURISCVState *env, int csrno,
         mask |= MNSTATUS_MNPV;
     }
 
+    if (env_archcpu(env)->cfg.ext_zicfilp) {
+        mask |= MNSTATUS_MNPELP;
+    }
+
     /* mnstatus.mnie can only be cleared by hardware. */
     env->mnstatus = (env->mnstatus & MNSTATUS_NMIE) | (val & mask);
     return RISCV_EXCP_NONE;
-- 
2.55.0.windows.2