From 2cb9f413198d1af84f23f9a432070cc37525aafd Mon Sep 17 00:00:00 2001
From: kettenis <kettenis@openbsd.org>
Date: Mon, 27 Mar 2023 17:49:13 +0000
Subject: [PATCH] Show BT and SBSS features in dmesg.

ok deraadt@
---
 sys/arch/arm64/arm64/cpu.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/sys/arch/arm64/arm64/cpu.c b/sys/arch/arm64/arm64/cpu.c
index 3f27da56496..755d76e0ef5 100644
--- a/sys/arch/arm64/arm64/cpu.c
+++ b/sys/arch/arm64/arm64/cpu.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.c,v 1.86 2023/02/20 00:01:16 patrick Exp $	*/
+/*	$OpenBSD: cpu.c,v 1.87 2023/03/27 17:49:13 kettenis Exp $	*/
 
 /*
  * Copyright (c) 2016 Dale Rahn <drahn@dalerahn.com>
@@ -732,6 +732,23 @@ cpu_identify(struct cpu_info *ci)
 		sep = ",";
 	}
 
+	/*
+	 * ID_AA64PFR0
+	 */
+	id = READ_SPECIALREG(id_aa64pfr1_el1);
+
+	if (ID_AA64PFR1_BT(id) >= ID_AA64PFR1_BT_IMPL) {
+		printf("%sBT", sep);
+		sep = ",";
+	}
+
+	if (ID_AA64PFR1_SBSS(id) >= ID_AA64PFR1_SBSS_PSTATE) {
+		printf("%sSBSS", sep);
+		sep = ",";
+	}
+	if (ID_AA64PFR1_SBSS(id) >= ID_AA64PFR1_SBSS_PSTATE_MSR)
+		printf("+MSR");
+
 #ifdef CPU_DEBUG
 	id = READ_SPECIALREG(id_aa64afr0_el1);
 	printf("\nID_AA64AFR0_EL1: 0x%016llx", id);
-- 
2.20.1