[src/trunk]: src/sys/arch/x86/x86 Interim workaround for modern Xeons that do...

[sborrill <sborrill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/33f39b88fc25
branches:  trunk
changeset: 749594:33f39b88fc25
user:      sborrill <sborrill%NetBSD.org@localhost>
date:      Thu Dec 03 14:47:15 2009 +0000

description:
Interim workaround for modern Xeons that don't have the simplistic view of
bus speed and therefore do not support MSR_FSB_FREQ (e.g. X3400). In the
long-term, ACPI should be used for this (c.f. FreeBSD).

diffstat:

 sys/arch/x86/x86/intel_busclock.c |  16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)

diffs (37 lines):

diff -r 2d4c6b4ec2f3 -r 33f39b88fc25 sys/arch/x86/x86/intel_busclock.c
--- a/sys/arch/x86/x86/intel_busclock.c Thu Dec 03 14:44:12 2009 +0000
+++ b/sys/arch/x86/x86/intel_busclock.c Thu Dec 03 14:47:15 2009 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: intel_busclock.c,v 1.8 2009/10/02 15:05:42 jmcneill Exp $      */
+/*     $NetBSD: intel_busclock.c,v 1.9 2009/12/03 14:47:15 sborrill Exp $      */
 
 /*-
  * Copyright (c) 1999, 2000, 2001 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: intel_busclock.c,v 1.8 2009/10/02 15:05:42 jmcneill Exp $");
+__KERNEL_RCSID(0, "$NetBSD: intel_busclock.c,v 1.9 2009/12/03 14:47:15 sborrill Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -127,6 +127,18 @@
                }
                break;
        case 0xe: /* Core Duo/Solo */
+               /*
+                * XXX
+                * Newer CPUs will GP when attemping to access MSR_FSB_FREQ.
+                * In the long-term, use ACPI instead of all this.
+                */
+               switch (CPUID2EXTMODEL(ci->ci_signature)) {
+               case 0x1:
+                       aprint_debug("%s: unable to determine bus speed",
+                           device_xname(ci->ci_dev));
+                       goto print_msr;
+               }
+               /* FALLTHROUGH */
        case 0xf: /* Core Xeon */
                msr = rdmsr(MSR_FSB_FREQ);
                bus = (msr >> 0) & 0x7;