ACPI: introduce kernel parameter acpi_sleep=sci_force_enable

Introduce kernel parameter acpi_sleep=sci_force_enable some laptop requires SCI_EN being set directly on resume, or else they hung somewhere in the resume code path. We already have a blacklist for these laptops but we still need this option, especially when debugging some suspend/resume problems, in case there are systems that need this workaround and are not yet in the blacklist. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>

ACPI: introduce kernel parameter acpi_sleep=sci_force_enable
Introduce kernel parameter acpi_sleep=sci_force_enable some laptop requires SCI_EN being set directly on resume, or else they hung somewhere in the resume code path. We already have a blacklist for these laptops but we still need this option, especially when debugging some suspend/resume problems, in case there are systems that need this workaround and are not yet in the blacklist. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
Zhang Rui · Len Brown
1 parent 6b7b284958
Showing 4 changed files with 24 additions and 13 deletions Side-by-side Diff
Documentation/kernel-parameters.txt
arch/x86/kernel/acpi/sleep.c
drivers/acpi/sleep.c
include/linux/acpi.h
@@ -240,7 +240,7 @@
  
 	acpi_sleep=	[HW,ACPI] Sleep options
 			Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
-				  old_ordering, s4_nonvs }
+				  old_ordering, s4_nonvs, sci_force_enable }
 			See Documentation/power/video.txt for information on
 			s3_bios and s3_mode.
 			s3_beep is for debugging; it makes the PC's speaker beep
@@ -253,6 +253,9 @@
 			of _PTS is used by default).
 			s4_nonvs prevents the kernel from saving/restoring the
 			ACPI NVS memory during hibernation.
+			sci_force_enable causes the kernel to set SCI_EN directly
+			on resume from S1/S3 (which is against the ACPI spec,
+			but some broken systems don't work without it).
  
 	acpi_use_timer_override [HW,ACPI]
 			Use timer override. For some broken Nvidia NF5 boards
@@ -162,6 +162,8 @@
 #endif
 		if (strncmp(str, "old_ordering", 12) == 0)
 			acpi_old_suspend_ordering();
+		if (strncmp(str, "sci_force_enable", 16) == 0)
+			acpi_set_sci_en_on_resume();
 		str = strchr(str, ',');
 		if (str != NULL)
 			str += strspn(str, ", \t");
@@ -81,6 +81,23 @@
 #ifdef CONFIG_ACPI_SLEEP
 static u32 acpi_target_sleep_state = ACPI_STATE_S0;
 /*
+ * According to the ACPI specification the BIOS should make sure that ACPI is
+ * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states.  Still,
+ * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
+ * on such systems during resume.  Unfortunately that doesn't help in
+ * particularly pathological cases in which SCI_EN has to be set directly on
+ * resume, although the specification states very clearly that this flag is
+ * owned by the hardware.  The set_sci_en_on_resume variable will be set in such
+ * cases.
+ */
+static bool set_sci_en_on_resume;
+
+void __init acpi_set_sci_en_on_resume(void)
+{
+	set_sci_en_on_resume = true;
+}
+
+/*
  * ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
  * user to request that behavior by using the 'acpi_old_suspend_ordering'
  * kernel command line option that causes the following variable to be set.
@@ -170,18 +187,6 @@
 #endif /* CONFIG_ACPI_SLEEP */
  
 #ifdef CONFIG_SUSPEND
-/*
- * According to the ACPI specification the BIOS should make sure that ACPI is
- * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states.  Still,
- * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
- * on such systems during resume.  Unfortunately that doesn't help in
- * particularly pathological cases in which SCI_EN has to be set directly on
- * resume, although the specification states very clearly that this flag is
- * owned by the hardware.  The set_sci_en_on_resume variable will be set in such
- * cases.
- */
-static bool set_sci_en_on_resume;
-
 extern void do_suspend_lowlevel(void);
  
 static u32 acpi_suspend_states[] = {
@@ -251,6 +251,7 @@
 void __init acpi_no_s4_hw_signature(void);
 void __init acpi_old_suspend_ordering(void);
 void __init acpi_s4_no_nvs(void);
+void __init acpi_set_sci_en_on_resume(void);
 #endif /* CONFIG_PM_SLEEP */
  
 struct acpi_osc_context {
...	...	@@ -240,7 +240,7 @@
240	240
241	241	acpi_sleep= [HW,ACPI] Sleep options
242	242	Format: { s3_bios, s3_mode, s3_beep, s4_nohwsig,
243		- old_ordering, s4_nonvs }
	243	+ old_ordering, s4_nonvs, sci_force_enable }
244	244	See Documentation/power/video.txt for information on
245	245	s3_bios and s3_mode.
246	246	s3_beep is for debugging; it makes the PC's speaker beep
...	...	@@ -253,6 +253,9 @@
253	253	of _PTS is used by default).
254	254	s4_nonvs prevents the kernel from saving/restoring the
255	255	ACPI NVS memory during hibernation.
	256	+ sci_force_enable causes the kernel to set SCI_EN directly
	257	+ on resume from S1/S3 (which is against the ACPI spec,
	258	+ but some broken systems don't work without it).
256	259
257	260	acpi_use_timer_override [HW,ACPI]
258	261	Use timer override. For some broken Nvidia NF5 boards
...	...	@@ -162,6 +162,8 @@
162	162	#endif
163	163	if (strncmp(str, "old_ordering", 12) == 0)
164	164	acpi_old_suspend_ordering();
	165	+ if (strncmp(str, "sci_force_enable", 16) == 0)
	166	+ acpi_set_sci_en_on_resume();
165	167	str = strchr(str, ',');
166	168	if (str != NULL)
167	169	str += strspn(str, ", \t");
...	...	@@ -81,6 +81,23 @@
81	81	#ifdef CONFIG_ACPI_SLEEP
82	82	static u32 acpi_target_sleep_state = ACPI_STATE_S0;
83	83	/*
	84	+ * According to the ACPI specification the BIOS should make sure that ACPI is
	85	+ * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states. Still,
	86	+ * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
	87	+ * on such systems during resume. Unfortunately that doesn't help in
	88	+ * particularly pathological cases in which SCI_EN has to be set directly on
	89	+ * resume, although the specification states very clearly that this flag is
	90	+ * owned by the hardware. The set_sci_en_on_resume variable will be set in such
	91	+ * cases.
	92	+ */
	93	+static bool set_sci_en_on_resume;
	94	+
	95	+void __init acpi_set_sci_en_on_resume(void)
	96	+{
	97	+ set_sci_en_on_resume = true;
	98	+}
	99	+
	100	+/*
84	101	* ACPI 1.0 wants us to execute _PTS before suspending devices, so we allow the
85	102	* user to request that behavior by using the 'acpi_old_suspend_ordering'
86	103	* kernel command line option that causes the following variable to be set.
...	...	@@ -170,18 +187,6 @@
170	187	#endif /* CONFIG_ACPI_SLEEP */
171	188
172	189	#ifdef CONFIG_SUSPEND
173		-/*
174		- * According to the ACPI specification the BIOS should make sure that ACPI is
175		- * enabled and SCI_EN bit is set on wake-up from S1 - S3 sleep states. Still,
176		- * some BIOSes don't do that and therefore we use acpi_enable() to enable ACPI
177		- * on such systems during resume. Unfortunately that doesn't help in
178		- * particularly pathological cases in which SCI_EN has to be set directly on
179		- * resume, although the specification states very clearly that this flag is
180		- * owned by the hardware. The set_sci_en_on_resume variable will be set in such
181		- * cases.
182		- */
183		-static bool set_sci_en_on_resume;
184		-
185	190	extern void do_suspend_lowlevel(void);
186	191
187	192	static u32 acpi_suspend_states[] = {
...	...	@@ -251,6 +251,7 @@
251	251	void __init acpi_no_s4_hw_signature(void);
252	252	void __init acpi_old_suspend_ordering(void);
253	253	void __init acpi_s4_no_nvs(void);
	254	+void __init acpi_set_sci_en_on_resume(void);
254	255	#endif /* CONFIG_PM_SLEEP */
255	256
256	257	struct acpi_osc_context {