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authorRafael J. Wysocki <rjw@sisk.pl>2010-07-23 16:59:09 -0400
committerLen Brown <len.brown@intel.com>2010-07-24 23:26:09 -0400
commit72ad5d77fb981963edae15eee8196c80238f5ed0 (patch)
treea6fa9a0b9ba924fd2dd91debf3e8ab04e8084338 /drivers/acpi/sleep.c
parentb37fa16e78d6f9790462b3181602a26b5af36260 (diff)
ACPI / Sleep: Allow the NVS saving to be skipped during suspend to RAM
Commit 2a6b69765ad794389f2fc3e14a0afa1a995221c2 (ACPI: Store NVS state even when entering suspend to RAM) caused the ACPI suspend code save the NVS area during suspend and restore it during resume unconditionally, although it is known that some systems need to use acpi_sleep=s4_nonvs for hibernation to work. To allow the affected systems to avoid saving and restoring the NVS area during suspend to RAM and resume, introduce kernel command line option acpi_sleep=nonvs and make acpi_sleep=s4_nonvs work as its alias temporarily (add acpi_sleep=s4_nonvs to the feature removal file). Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16396 . Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Reported-and-tested-by: tomas m <tmezzadra@gmail.com> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/sleep.c')
-rw-r--r--drivers/acpi/sleep.c35
1 files changed, 17 insertions, 18 deletions
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index 5b7c52e4a00f..2862c781b372 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -82,6 +82,20 @@ static int acpi_sleep_prepare(u32 acpi_state)
82static u32 acpi_target_sleep_state = ACPI_STATE_S0; 82static u32 acpi_target_sleep_state = ACPI_STATE_S0;
83 83
84/* 84/*
85 * The ACPI specification wants us to save NVS memory regions during hibernation
86 * and to restore them during the subsequent resume. Windows does that also for
87 * suspend to RAM. However, it is known that this mechanism does not work on
88 * all machines, so we allow the user to disable it with the help of the
89 * 'acpi_sleep=nonvs' kernel command line option.
90 */
91static bool nvs_nosave;
92
93void __init acpi_nvs_nosave(void)
94{
95 nvs_nosave = true;
96}
97
98/*
85 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the 99 * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
86 * user to request that behavior by using the 'acpi_old_suspend_ordering' 100 * user to request that behavior by using the 'acpi_old_suspend_ordering'
87 * kernel command line option that causes the following variable to be set. 101 * kernel command line option that causes the following variable to be set.
@@ -197,8 +211,7 @@ static int acpi_suspend_begin(suspend_state_t pm_state)
197 u32 acpi_state = acpi_suspend_states[pm_state]; 211 u32 acpi_state = acpi_suspend_states[pm_state];
198 int error = 0; 212 int error = 0;
199 213
200 error = suspend_nvs_alloc(); 214 error = nvs_nosave ? 0 : suspend_nvs_alloc();
201
202 if (error) 215 if (error)
203 return error; 216 return error;
204 217
@@ -388,20 +401,6 @@ static struct dmi_system_id __initdata acpisleep_dmi_table[] = {
388#endif /* CONFIG_SUSPEND */ 401#endif /* CONFIG_SUSPEND */
389 402
390#ifdef CONFIG_HIBERNATION 403#ifdef CONFIG_HIBERNATION
391/*
392 * The ACPI specification wants us to save NVS memory regions during hibernation
393 * and to restore them during the subsequent resume. However, it is not certain
394 * if this mechanism is going to work on all machines, so we allow the user to
395 * disable this mechanism using the 'acpi_sleep=s4_nonvs' kernel command line
396 * option.
397 */
398static bool s4_no_nvs;
399
400void __init acpi_s4_no_nvs(void)
401{
402 s4_no_nvs = true;
403}
404
405static unsigned long s4_hardware_signature; 404static unsigned long s4_hardware_signature;
406static struct acpi_table_facs *facs; 405static struct acpi_table_facs *facs;
407static bool nosigcheck; 406static bool nosigcheck;
@@ -415,7 +414,7 @@ static int acpi_hibernation_begin(void)
415{ 414{
416 int error; 415 int error;
417 416
418 error = s4_no_nvs ? 0 : suspend_nvs_alloc(); 417 error = nvs_nosave ? 0 : suspend_nvs_alloc();
419 if (!error) { 418 if (!error) {
420 acpi_target_sleep_state = ACPI_STATE_S4; 419 acpi_target_sleep_state = ACPI_STATE_S4;
421 acpi_sleep_tts_switch(acpi_target_sleep_state); 420 acpi_sleep_tts_switch(acpi_target_sleep_state);
@@ -510,7 +509,7 @@ static int acpi_hibernation_begin_old(void)
510 error = acpi_sleep_prepare(ACPI_STATE_S4); 509 error = acpi_sleep_prepare(ACPI_STATE_S4);
511 510
512 if (!error) { 511 if (!error) {
513 if (!s4_no_nvs) 512 if (!nvs_nosave)
514 error = suspend_nvs_alloc(); 513 error = suspend_nvs_alloc();
515 if (!error) 514 if (!error)
516 acpi_target_sleep_state = ACPI_STATE_S4; 515 acpi_target_sleep_state = ACPI_STATE_S4;