Previous ELP is restored by xRET

riscv · Nov 28, 2023 · 2501abc · 2501abc
1 parent 97e3fcf
commit 2501abc
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/model/riscv_sys_control.sail b/model/riscv_sys_control.sail
@@ -477,6 +477,10 @@ function trap_handler(del_priv : Privilege, intr : bool, c : exc_code, pc : xlen
   };
 }
 
+/* Zicfilp : extension to restore elp */
+val zicfilp_set_elp_to_mpelp : (unit) -> unit
+val zicfilp_set_elp_to_spelp : (unit) -> unit
+
 function exception_handler(cur_priv : Privilege, ctl : ctl_result,
                            pc: xlenbits) -> xlenbits = {
   match (cur_priv, ctl) {
@@ -496,6 +500,9 @@ function exception_handler(cur_priv : Privilege, ctl : ctl_result,
       if   cur_privilege != Machine
       then mstatus->MPRV() = 0b0;
 
+      /* Zicfilp: extension to restore ELP */
+      zicfilp_set_elp_to_mpelp();
+
       if   get_config_print_reg()
       then print_reg("CSR mstatus <- " ^ BitStr(mstatus.bits()));
       if   get_config_print_platform()
@@ -513,6 +520,9 @@ function exception_handler(cur_priv : Privilege, ctl : ctl_result,
       if   cur_privilege != Machine
       then mstatus->MPRV() = 0b0;
 
+      /* Zicfilp: extension to restore ELP */
+      zicfilp_set_elp_to_spelp();
+
       if   get_config_print_reg()
       then print_reg("CSR mstatus <- " ^ BitStr(mstatus.bits()));
       if   get_config_print_platform()