target/riscv: Clear mstatus.MPRV when leaving M-mode for priv spec 1.12+

Since priv spec v1.12, MRET and SRET now clear mstatus.MPRV when
leaving M-mode.

Signed-off-by: Bin Meng <bmeng@tinylab.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221207090037.281452-2-bmeng@tinylab.org>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c
index a047d38152b47934e16e1e38ace98dc885a77fa1..878bcb03b8b227813976ff361a00da8c9bebfa63 100644 (file)
--- a/target/riscv/op_helper.c
+++ b/target/riscv/op_helper.c
@@ -154,6 +154,9 @@ target_ulong helper_sret(CPURISCVState *env)
                         get_field(mstatus, MSTATUS_SPIE));
     mstatus = set_field(mstatus, MSTATUS_SPIE, 1);
     mstatus = set_field(mstatus, MSTATUS_SPP, PRV_U);
+    if (env->priv_ver >= PRIV_VERSION_1_12_0) {
+        mstatus = set_field(mstatus, MSTATUS_MPRV, 0);
+    }
     env->mstatus = mstatus;
 
     if (riscv_has_ext(env, RVH) && !riscv_cpu_virt_enabled(env)) {
@@ -203,6 +206,9 @@ target_ulong helper_mret(CPURISCVState *env)
     mstatus = set_field(mstatus, MSTATUS_MPIE, 1);
     mstatus = set_field(mstatus, MSTATUS_MPP, PRV_U);
     mstatus = set_field(mstatus, MSTATUS_MPV, 0);
+    if ((env->priv_ver >= PRIV_VERSION_1_12_0) && (prev_priv != PRV_M)) {
+        mstatus = set_field(mstatus, MSTATUS_MPRV, 0);
+    }
     env->mstatus = mstatus;
     riscv_cpu_set_mode(env, prev_priv);