From b430acbd7c4b919886fa7fd92eeb7a695f1940d3 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Thu, 6 May 2010 17:41:08 -0400 Subject: ACPICA: simplify SCI_EN workaround acpi_hw_set_mode() double checks its effectiveness by calling acpi_hw_get_mode() -- polling up to 3 seconds. It would be more logical for its caller, acpi_enable() acpi_enable() to do the double-checking. (lets assume that acpi_disable() isn't interesting) The ACPI specification is unclear on this point. Some parts say that the BIOS sets SCI_EN and then returns to the OS, but one part says "OSPM polls the SCI_EN bit until it is sampled SET". The systems I have on hand do the former, SCI_EN is observed to be set upon return from the BIOS. So we move the check up out of acpi_hw_set_mode() up into acpi_enable() where it makes logical sense. Then we replace the 3-second polling loop with a single check. If this check fails, we'll see: "Hardware did not enter ACPI mode" and the system will bail out of ACPI initialization and likely fail to boot. If we see that in practice, we can restore the polling, but put it into acpi_enable. This patch is important if acpi_enable() is used in the resume from S3 path. Many systems today are seen coming back from S3 with SCI_EN off, and then failing to set SCI_EN in response to acpi_enable(). Those systems will take 3 seconds longer to resume due to this loop. However, it is possible that we will not use acpi_enable() in the S3 resume path, and bang SCI_EN directly, which would make the loop harmless, as it would be invisible to all systems except those that need it. Signed-off-by: Len Brown diff --git a/drivers/acpi/acpica/evxfevnt.c b/drivers/acpi/acpica/evxfevnt.c index 5ff32c7..bfbe291 100644 --- a/drivers/acpi/acpica/evxfevnt.c +++ b/drivers/acpi/acpica/evxfevnt.c @@ -69,7 +69,7 @@ acpi_ev_get_gpe_device(struct acpi_gpe_xrupt_info *gpe_xrupt_info, acpi_status acpi_enable(void) { - acpi_status status = AE_OK; + acpi_status status; ACPI_FUNCTION_TRACE(acpi_enable); @@ -84,21 +84,30 @@ acpi_status acpi_enable(void) if (acpi_hw_get_mode() == ACPI_SYS_MODE_ACPI) { ACPI_DEBUG_PRINT((ACPI_DB_INIT, "System is already in ACPI mode\n")); - } else { - /* Transition to ACPI mode */ + return_ACPI_STATUS(AE_OK); + } - status = acpi_hw_set_mode(ACPI_SYS_MODE_ACPI); - if (ACPI_FAILURE(status)) { - ACPI_ERROR((AE_INFO, - "Could not transition to ACPI mode")); - return_ACPI_STATUS(status); - } + /* Transition to ACPI mode */ - ACPI_DEBUG_PRINT((ACPI_DB_INIT, - "Transition to ACPI mode successful\n")); + status = acpi_hw_set_mode(ACPI_SYS_MODE_ACPI); + if (ACPI_FAILURE(status)) { + ACPI_ERROR((AE_INFO, + "Could not transition to ACPI mode")); + return_ACPI_STATUS(status); } - return_ACPI_STATUS(status); + /* Sanity check that transition succeeded */ + + if (acpi_hw_get_mode() != ACPI_SYS_MODE_ACPI) { + ACPI_ERROR((AE_INFO, + "Hardware did not enter ACPI mode")); + return_ACPI_STATUS(AE_NO_HARDWARE_RESPONSE); + } + + ACPI_DEBUG_PRINT((ACPI_DB_INIT, + "Transition to ACPI mode successful\n")); + + return_ACPI_STATUS(AE_OK); } ACPI_EXPORT_SYMBOL(acpi_enable) diff --git a/drivers/acpi/acpica/hwacpi.c b/drivers/acpi/acpica/hwacpi.c index 679a112..b44274a 100644 --- a/drivers/acpi/acpica/hwacpi.c +++ b/drivers/acpi/acpica/hwacpi.c @@ -63,7 +63,6 @@ acpi_status acpi_hw_set_mode(u32 mode) { acpi_status status; - u32 retry; ACPI_FUNCTION_TRACE(hw_set_mode); @@ -125,24 +124,7 @@ acpi_status acpi_hw_set_mode(u32 mode) return_ACPI_STATUS(status); } - /* - * Some hardware takes a LONG time to switch modes. Give them 3 sec to - * do so, but allow faster systems to proceed more quickly. - */ - retry = 3000; - while (retry) { - if (acpi_hw_get_mode() == mode) { - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Mode %X successfully enabled\n", - mode)); - return_ACPI_STATUS(AE_OK); - } - acpi_os_stall(1000); - retry--; - } - - ACPI_ERROR((AE_INFO, "Hardware did not change modes")); - return_ACPI_STATUS(AE_NO_HARDWARE_RESPONSE); + return_ACPI_STATUS(AE_OK); } /******************************************************************************* -- cgit v0.10.2 From b6dacf63e9fb2e7a1369843d6cef332f76fca6a3 Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Tue, 11 May 2010 13:49:25 -0400 Subject: ACPI: Unconditionally set SCI_EN on resume The ACPI spec tells us that the firmware will reenable SCI_EN on resume. Reality disagrees in some cases. The ACPI spec tells us that the only way to set SCI_EN is via an SMM call. https://bugzilla.kernel.org/show_bug.cgi?id=13745 shows us that doing so may break machines. Tracing the ACPI calls made by Windows shows that it unconditionally sets SCI_EN on resume with a direct register write, and therefore the overwhelming probability is that everything is fine with this behaviour. Signed-off-by: Matthew Garrett Tested-by: Rafael J. Wysocki Signed-off-by: Len Brown diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index f996103..82e5086 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -162,8 +162,6 @@ static int __init acpi_sleep_setup(char *str) #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"); diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c index baa76bb..4ab2275 100644 --- a/drivers/acpi/sleep.c +++ b/drivers/acpi/sleep.c @@ -80,22 +80,6 @@ static int acpi_sleep_prepare(u32 acpi_state) #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 @@ -253,11 +237,8 @@ static int acpi_suspend_enter(suspend_state_t pm_state) break; } - /* If ACPI is not enabled by the BIOS, we need to enable it here. */ - if (set_sci_en_on_resume) - acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1); - else - acpi_enable(); + /* This violates the spec but is required for bug compatibility. */ + acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1); /* Reprogram control registers and execute _BFS */ acpi_leave_sleep_state_prep(acpi_state); @@ -346,12 +327,6 @@ static int __init init_old_suspend_ordering(const struct dmi_system_id *d) return 0; } -static int __init init_set_sci_en_on_resume(const struct dmi_system_id *d) -{ - set_sci_en_on_resume = true; - return 0; -} - static struct dmi_system_id __initdata acpisleep_dmi_table[] = { { .callback = init_old_suspend_ordering, @@ -370,22 +345,6 @@ static struct dmi_system_id __initdata acpisleep_dmi_table[] = { }, }, { - .callback = init_set_sci_en_on_resume, - .ident = "Apple MacBook 1,1", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."), - DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Apple MacMini 1,1", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."), - DMI_MATCH(DMI_PRODUCT_NAME, "Macmini1,1"), - }, - }, - { .callback = init_old_suspend_ordering, .ident = "Asus Pundit P1-AH2 (M2N8L motherboard)", .matches = { @@ -394,94 +353,6 @@ static struct dmi_system_id __initdata acpisleep_dmi_table[] = { }, }, { - .callback = init_set_sci_en_on_resume, - .ident = "Toshiba Satellite L300", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"), - DMI_MATCH(DMI_PRODUCT_NAME, "Satellite L300"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard HP G7000 Notebook PC", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "HP G7000 Notebook PC"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard HP Pavilion dv3 Notebook PC", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv3 Notebook PC"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard Pavilion dv4", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv4"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard Pavilion dv7", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dv7"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard Compaq Presario C700 Notebook PC", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario C700 Notebook PC"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Hewlett-Packard Compaq Presario CQ40 Notebook PC", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), - DMI_MATCH(DMI_PRODUCT_NAME, "Compaq Presario CQ40 Notebook PC"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Lenovo ThinkPad T410", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), - DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T410"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Lenovo ThinkPad T510", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), - DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T510"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Lenovo ThinkPad W510", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), - DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W510"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Lenovo ThinkPad X201[s]", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), - DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201"), - }, - }, - { .callback = init_old_suspend_ordering, .ident = "Panasonic CF51-2L", .matches = { @@ -490,30 +361,6 @@ static struct dmi_system_id __initdata acpisleep_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "CF51-2L"), }, }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Dell Studio 1558", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), - DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1558"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Dell Studio 1557", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), - DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1557"), - }, - }, - { - .callback = init_set_sci_en_on_resume, - .ident = "Dell Studio 1555", - .matches = { - DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), - DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1555"), - }, - }, {}, }; #endif /* CONFIG_SUSPEND */ diff --git a/include/linux/acpi.h b/include/linux/acpi.h index b926afe..87ca491 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -251,7 +251,6 @@ int acpi_check_mem_region(resource_size_t start, resource_size_t n, 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 { -- cgit v0.10.2