diff mbox series

[v6,7/9] target/riscv: Implement Smdbltrp sret, mret and mnret behavior

Message ID 20241128141230.284320-8-cleger@rivosinc.com (mailing list archive)
State New
Headers show
Series target/riscv: Add support for Smdbltrp and Ssdbltrp extensions | expand

Commit Message

Clément Léger Nov. 28, 2024, 2:12 p.m. UTC 
When the Ssdbltrp extension is enabled, SSTATUS.MDT field is cleared
when executing sret if executed in M-mode. When executing mret/mnret,
SSTATUS.MDT is cleared.

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
---
 target/riscv/op_helper.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c
index eeacb2d1a1..9de4df207c 100644
--- a/target/riscv/op_helper.c
+++ b/target/riscv/op_helper.c
@@ -299,6 +299,9 @@  target_ulong helper_sret(CPURISCVState *env)
         }
         mstatus = set_field(mstatus, MSTATUS_SDT, 0);
     }
+    if (riscv_cpu_cfg(env)->ext_smdbltrp && env->priv >= PRV_M) {
+        mstatus = set_field(mstatus, MSTATUS_MDT, 0);
+    }
     if (env->priv_ver >= PRIV_VERSION_1_12_0) {
         mstatus = set_field(mstatus, MSTATUS_MPRV, 0);
     }
@@ -384,6 +387,9 @@  target_ulong helper_mret(CPURISCVState *env)
     if (riscv_cpu_cfg(env)->ext_ssdbltrp) {
         mstatus = ssdbltrp_mxret(env, mstatus, prev_priv, prev_virt);
     }
+    if (riscv_cpu_cfg(env)->ext_smdbltrp) {
+        mstatus = set_field(mstatus, MSTATUS_MDT, 0);
+    }
     if ((env->priv_ver >= PRIV_VERSION_1_12_0) && (prev_priv != PRV_M)) {
         mstatus = set_field(mstatus, MSTATUS_MPRV, 0);
     }
@@ -429,6 +435,12 @@  target_ulong helper_mnret(CPURISCVState *env)
         env->mstatus = ssdbltrp_mxret(env, env->mstatus, prev_priv, prev_virt);
     }
 
+    if (riscv_cpu_cfg(env)->ext_smdbltrp) {
+        if (prev_priv < PRV_M) {
+            env->mstatus = set_field(env->mstatus, MSTATUS_MDT, 0);
+        }
+    }
+
     if (riscv_has_ext(env, RVH) && prev_virt) {
         riscv_cpu_swap_hypervisor_regs(env);
     }