svn commit: r219277 - stable/8/sys/x86/cpufreq

[Jung-uk Kim]

Author: jkim
Date: Fri Mar  4 22:59:14 2011
New Revision: 219277
URL: http://svn.freebsd.org/changeset/base/219277

Log:
  MFC:	r219046
  
  Set C1 "I/O then Halt" capability bit for Intel EIST.  Some broken BIOSes
  refuse to load external SSDTs if this bit is unset for _PDC.

Modified:
  stable/8/sys/x86/cpufreq/est.c
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)

Modified: stable/8/sys/x86/cpufreq/est.c
==============================================================================
--- stable/8/sys/x86/cpufreq/est.c	Fri Mar  4 22:26:41 2011	(r219276)
+++ stable/8/sys/x86/cpufreq/est.c	Fri Mar  4 22:59:14 2011	(r219277)
@@ -945,8 +945,11 @@ static int
 est_features(driver_t *driver, u_int *features)
 {
 
-	/* Notify the ACPI CPU that we support direct access to MSRs */
-	*features = ACPI_CAP_PERF_MSRS;
+	/*
+	 * Notify the ACPI CPU that we support direct access to MSRs.
+	 * XXX C1 "I/O then Halt" seems necessary for some broken BIOS.
+	 */
+	*features = ACPI_CAP_PERF_MSRS | ACPI_CAP_C1_IO_HALT;
 	return (0);
 }