From 96f15efcea94545987715f453a8c2b8ea592d000 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Fri, 17 Apr 2009 23:32:20 -0400 Subject: ACPI: Disable _GTS and _BFS support by default Executing BIOS code paths not exercised by Windows tends to get Linux into trouble. However, if a system does benefit from _GTS or _BFS, acpi.gts=1 an acpi.bfs=1 are now available to enable them. http://bugzilla.kernel.org/show_bug.cgi?id=13041 Signed-off-by: Len Brown --- drivers/acpi/sleep.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'drivers/acpi/sleep.c') diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 779e4e500df4..9042875ac942 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -713,6 +713,32 @@ static void acpi_power_off(void) acpi_enter_sleep_state(ACPI_STATE_S5); } +/* + * ACPI 2.0 created the optional _GTS and _BFS, + * but industry adoption has been neither rapid nor broad. + * + * Linux gets into trouble when it executes poorly validated + * paths through the BIOS, so disable _GTS and _BFS by default, + * but do speak up and offer the option to enable them. + */ +void __init acpi_gts_bfs_check(void) +{ + acpi_handle dummy; + + if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__GTS, &dummy))) + { + printk(KERN_NOTICE PREFIX "BIOS offers _GTS\n"); + printk(KERN_NOTICE PREFIX "If \"acpi.gts=1\" improves suspend, " + "please notify linux-acpi@vger.kernel.org\n"); + } + if (ACPI_SUCCESS(acpi_get_handle(ACPI_ROOT_OBJECT, METHOD_NAME__BFS, &dummy))) + { + printk(KERN_NOTICE PREFIX "BIOS offers _BFS\n"); + printk(KERN_NOTICE PREFIX "If \"acpi.bfs=1\" improves resume, " + "please notify linux-acpi@vger.kernel.org\n"); + } +} + int __init acpi_sleep_init(void) { acpi_status status; @@ -771,5 +797,6 @@ int __init acpi_sleep_init(void) * object can also be evaluated when the system enters S5. */ register_reboot_notifier(&tts_notifier); + acpi_gts_bfs_check(); return 0; } -- cgit v1.2.1 From 6a7c7eaf71b636f197d73b381a2ab729ebdcfb2e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 19 Apr 2009 20:08:42 +0200 Subject: PM/Suspend: Introduce two new platform callbacks to avoid breakage Commit 900af0d973856d6feb6fc088c2d0d3fde57707d3 (PM: Change suspend code ordering) changed the ordering of suspend code in such a way that the platform .prepare() callback is now executed after the device drivers' late suspend callbacks have run. Unfortunately, this turns out to break ARM platforms that need to talk via I2C to power control devices during the .prepare() callback. For this reason introduce two new platform suspend callbacks, .prepare_late() and .wake(), that will be called just prior to disabling non-boot CPUs and right after bringing them back on line, respectively, and use them instead of .prepare() and .finish() for ACPI suspend. Make the PM core execute the .prepare() and .finish() platform suspend callbacks where they were executed previously (that is, right after calling the regular suspend methods provided by device drivers and right before executing their regular resume methods, respectively). It is not necessary to make analogous changes to the hibernation code and data structures at the moment, because they are only used by ACPI platforms. Signed-off-by: Rafael J. Wysocki Reported-by: Russell King Acked-by: Len Brown --- drivers/acpi/sleep.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/acpi/sleep.c') diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index 779e4e500df4..d060e6fd7fd5 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -300,9 +300,9 @@ static int acpi_suspend_state_valid(suspend_state_t pm_state) static struct platform_suspend_ops acpi_suspend_ops = { .valid = acpi_suspend_state_valid, .begin = acpi_suspend_begin, - .prepare = acpi_pm_prepare, + .prepare_late = acpi_pm_prepare, .enter = acpi_suspend_enter, - .finish = acpi_pm_finish, + .wake = acpi_pm_finish, .end = acpi_pm_end, }; @@ -328,9 +328,9 @@ static int acpi_suspend_begin_old(suspend_state_t pm_state) static struct platform_suspend_ops acpi_suspend_ops_old = { .valid = acpi_suspend_state_valid, .begin = acpi_suspend_begin_old, - .prepare = acpi_pm_disable_gpes, + .prepare_late = acpi_pm_disable_gpes, .enter = acpi_suspend_enter, - .finish = acpi_pm_finish, + .wake = acpi_pm_finish, .end = acpi_pm_end, .recover = acpi_pm_finish, }; -- cgit v1.2.1