[src/trunk]: src/sys/arch/x86/acpi Add a comment.

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

details:   https://anonhg.NetBSD.org/src/rev/ac854bce2757
branches:  trunk
changeset: 760792:ac854bce2757
user:      jruoho <jruoho%NetBSD.org@localhost>
date:      Thu Jan 13 03:45:38 2011 +0000

description:
Add a comment.

diffstat:

 sys/arch/x86/acpi/acpi_wakeup.c |  23 +++++++++++++++--------
 1 files changed, 15 insertions(+), 8 deletions(-)

diffs (44 lines):

diff -r ca416c711131 -r ac854bce2757 sys/arch/x86/acpi/acpi_wakeup.c
--- a/sys/arch/x86/acpi/acpi_wakeup.c   Thu Jan 13 03:40:50 2011 +0000
+++ b/sys/arch/x86/acpi/acpi_wakeup.c   Thu Jan 13 03:45:38 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: acpi_wakeup.c,v 1.26 2010/12/31 09:19:43 jruoho Exp $  */
+/*     $NetBSD: acpi_wakeup.c,v 1.27 2011/01/13 03:45:38 jruoho Exp $  */
 
 /*-
  * Copyright (c) 2002 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: acpi_wakeup.c,v 1.26 2010/12/31 09:19:43 jruoho Exp $");
+__KERNEL_RCSID(0, "$NetBSD: acpi_wakeup.c,v 1.27 2011/01/13 03:45:38 jruoho Exp $");
 
 /*-
  * Copyright (c) 2001 Takanori Watanabe <takawata%jp.freebsd.org@localhost>
@@ -341,12 +341,19 @@
        initrtclock(TIMER_FREQ);
        inittodr(time_second);
 
-       AcpiClearEvent(ACPI_EVENT_PMTIMER);
-       AcpiClearEvent(ACPI_EVENT_GLOBAL);
-       AcpiClearEvent(ACPI_EVENT_POWER_BUTTON);
-       AcpiClearEvent(ACPI_EVENT_SLEEP_BUTTON);
-       AcpiClearEvent(ACPI_EVENT_RTC);
-       AcpiHwDisableAllGpes ();
+       /*
+        * Clear fixed events (see e.g. ACPI 3.0, p. 62).
+        * Also prevent GPEs from misfiring by disabling
+        * all GPEs before interrupts are enabled. The
+        * AcpiLeaveSleepState() function will enable
+        * and handle the general purpose events later.
+        */
+       (void)AcpiClearEvent(ACPI_EVENT_PMTIMER);
+       (void)AcpiClearEvent(ACPI_EVENT_GLOBAL);
+       (void)AcpiClearEvent(ACPI_EVENT_POWER_BUTTON);
+       (void)AcpiClearEvent(ACPI_EVENT_SLEEP_BUTTON);
+       (void)AcpiClearEvent(ACPI_EVENT_RTC);
+       (void)AcpiHwDisableAllGpes();
 
        acpi_pci_link_resume();