On 8/30/24 09:34, Deepak Gupta wrote:
elp state is recorded in *status on trap entry (less privilege to higher
privilege) and restored in elp from *status on trap exit (higher to less
privilege).
Additionally this patch introduces a forward cfi helper function to
determine if current privilege has forward cfi is enabled or not based on
*envcfg (for U, VU, S, VU, HS) or mseccfg csr (for M). For qemu-user, a
new field `ufcfien` is introduced which is by default set to false and
helper function returns value deposited in `ufcfien` for qemu-user.
Patch description needs updating to remove ufcfien.
+bool cpu_get_fcfien(CPURISCVState *env)
+{
+ /* no cfi extension, return false */
+ if (!env_archcpu(env)->cfg.ext_zicfilp) {
+ return false;
+ }
+
+ switch (env->priv) {
+ case PRV_U:
+ if (riscv_has_ext(env, RVS)) {
+ return env->senvcfg & SENVCFG_LPE;
+ }
+ return env->menvcfg & MENVCFG_LPE;
+#ifndef CONFIG_USER_ONLY
+ case PRV_S:
+ if (env->virt_enabled) {
+ return env->henvcfg & HENVCFG_LPE;
+ }
+ return env->menvcfg & MENVCFG_LPE;
+ case PRV_M:
+ return env->mseccfg & MSECCFG_MLPE;
+#endif
+ default:
+ g_assert_not_reached();
+ }
+}
Excellent, thanks.
r~
