From 0f6bcda4cd4a053e69d1b2c18d653e6ddfb3bf29 Mon Sep 17 00:00:00 2001
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Mon, 15 Jul 2013 06:30:57 +0000
Subject: [PATCH] MFi386: add ddb "show sysregs" command.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
---
 sys/amd64/amd64/machdep.c | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index a1c61eb2c07..7a39ef8f43b 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -1228,6 +1228,36 @@ DB_SHOW_COMMAND(idt, db_show_idt)
 		ip++;
 	}
 }
+
+/* Show privileged registers. */
+DB_SHOW_COMMAND(sysregs, db_show_sysregs)
+{
+	struct {
+		uint16_t limit;
+		uint64_t base;
+	} __packed idtr, gdtr;
+	uint16_t ldt, tr;
+
+	__asm __volatile("sidt %0" : "=m" (idtr));
+	db_printf("idtr\t0x%016lx/%04x\n",
+	    (u_long)idtr.base, (u_int)idtr.limit);
+	__asm __volatile("sgdt %0" : "=m" (gdtr));
+	db_printf("gdtr\t0x%016lx/%04x\n",
+	    (u_long)gdtr.base, (u_int)gdtr.limit);
+	__asm __volatile("sldt %0" : "=r" (ldt));
+	db_printf("ldtr\t0x%04x\n", ldt);
+	__asm __volatile("str %0" : "=r" (tr));
+	db_printf("tr\t0x%04x\n", tr);
+	db_printf("cr0\t0x%016lx\n", rcr0());
+	db_printf("cr2\t0x%016lx\n", rcr2());
+	db_printf("cr3\t0x%016lx\n", rcr3());
+	db_printf("cr4\t0x%016lx\n", rcr4());
+	db_printf("EFER\t%016lx\n", rdmsr(MSR_EFER));
+	db_printf("FEATURES_CTL\t%016lx\n", rdmsr(MSR_IA32_FEATURE_CONTROL));
+	db_printf("DEBUG_CTL\t%016lx\n", rdmsr(MSR_DEBUGCTLMSR));
+	db_printf("PAT\t%016lx\n", rdmsr(MSR_PAT));
+	db_printf("GSBASE\t%016lx\n", rdmsr(MSR_GSBASE));
+}
 #endif
 
 void