SYS-OSS/FRET-qemu
4
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

target/riscv: Implement Smdbltrp sret, mret and mnret behavior

Browse Source 
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>
Message-ID: <20250110125441.3208676-8-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This commit is contained in:
Clément Léger 2025-01-10 13:54:38 +01:00 committed by Alistair Francis
parent d2e92f1c6d
commit f2efb6e793
1 changed files with 12 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
target/riscv/op_helper.c
View File

@ -306,6 +306,9 @@ 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);
}
@ -391,6 +394,9 @@ 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);
}
@ -436,6 +442,12 @@ 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);
}