From 9ebb4b712e1d6c97a999652d0b9105847eabd134 Mon Sep 17 00:00:00 2001
From: Alejandro Soto <alejandro@34project.org>
Date: Fri, 16 Dec 2022 22:20:01 -0600
Subject: Implement mode privilege checks in MMU

---
 rtl/core/psr.sv | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

(limited to 'rtl/core/psr.sv')

diff --git a/rtl/core/psr.sv b/rtl/core/psr.sv
index c1fe0fd..41982c0 100644
--- a/rtl/core/psr.sv
+++ b/rtl/core/psr.sv
@@ -17,7 +17,8 @@ module core_psr
 	output psr_intmask mask,
 	output psr_mode    mode,
 	output word        cpsr_rd,
-	                   spsr_rd
+	                   spsr_rd,
+	output logic       privileged
 );
 
 	typedef struct packed
@@ -54,6 +55,7 @@ module core_psr
 	assign wr_word = psr_wr;
 	assign cpsr_rd = cpsr_word;
 	assign spsr_rd = spsr_word;
+	assign privileged = |mode[3:0]; // Not user
 	assign {wr_state.flags, wr_state.mask, wr_state.mode} = {wr_word.nzcv, wr_word.if_, wr_word.m};
 
 `ifdef VERILATOR
-- 
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