From 8562c99cdd30217dea3609e268572f8764f401a5 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 13 Jun 2014 12:22:22 +0100 Subject: efi/reboot: Add generic wrapper around EfiResetSystem() Implement efi_reboot(), which is really just a wrapper around the EfiResetSystem() EFI runtime service, but it does at least allow us to funnel all callers through a single location. It also simplifies the callsites since users no longer need to check to see whether EFI_RUNTIME_SERVICES are enabled. Cc: Tony Luck Tested-by: Mark Salter Signed-off-by: Matt Fleming --- drivers/firmware/efi/reboot.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) create mode 100644 drivers/firmware/efi/reboot.c (limited to 'drivers/firmware/efi/reboot.c') diff --git a/drivers/firmware/efi/reboot.c b/drivers/firmware/efi/reboot.c new file mode 100644 index 000000000000..81bf925f70f5 --- /dev/null +++ b/drivers/firmware/efi/reboot.c @@ -0,0 +1,26 @@ +/* + * Copyright (C) 2014 Intel Corporation; author Matt Fleming + * Copyright (c) 2014 Red Hat, Inc., Mark Salter + */ +#include +#include + +void efi_reboot(enum reboot_mode reboot_mode, const char *__unused) +{ + int efi_mode; + + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return; + + switch (reboot_mode) { + case REBOOT_WARM: + case REBOOT_SOFT: + efi_mode = EFI_RESET_WARM; + break; + default: + efi_mode = EFI_RESET_COLD; + break; + } + + efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL); +} -- cgit v1.2.3 From 0c5ed61adbdbf2ca5de934642d5be1e971c498c1 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 13 Jun 2014 12:35:21 +0100 Subject: efi/reboot: Allow powering off machines using EFI Not only can EfiResetSystem() be used to reboot, it can also be used to power down machines. By and large, this functionality doesn't work very well across the range of EFI machines in the wild, so it should definitely only be used as a last resort. In an ideal world, this wouldn't be needed at all. Unfortunately, we're starting to see machines where EFI is the *only* reliable way to power down, and nothing else, not PCI, not ACPI, works. efi_poweroff_required() should be implemented on a per-architecture basis, since exactly when we should be using EFI runtime services is a platform-specific decision. There's no analogue for reboot because each architecture handles reboot very differently - the x86 code in particular is pretty complex. Patches to enable this for specific classes of hardware will be submitted separately. Tested-by: Mark Salter Signed-off-by: Matt Fleming --- drivers/firmware/efi/reboot.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'drivers/firmware/efi/reboot.c') diff --git a/drivers/firmware/efi/reboot.c b/drivers/firmware/efi/reboot.c index 81bf925f70f5..e9eeeb3c6345 100644 --- a/drivers/firmware/efi/reboot.c +++ b/drivers/firmware/efi/reboot.c @@ -24,3 +24,25 @@ void efi_reboot(enum reboot_mode reboot_mode, const char *__unused) efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL); } + +bool __weak efi_poweroff_required(void) +{ + return false; +} + +static void efi_power_off(void) +{ + efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL); +} + +static int __init efi_shutdown_init(void) +{ + if (!efi_enabled(EFI_RUNTIME_SERVICES)) + return -ENODEV; + + if (efi_poweroff_required()) + pm_power_off = efi_power_off; + + return 0; +} +late_initcall(efi_shutdown_init); -- cgit v1.2.3 From 44be28e9dd9880dca3e2cbf7a844f2114e67f2cb Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 13 Jun 2014 12:39:55 +0100 Subject: x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag It appears that the BayTrail-T class of hardware requires EFI in order to powerdown and reboot and no other reliable method exists. This quirk is generally applicable to all hardware that has the ACPI Hardware Reduced bit set, since usually ACPI would be the preferred method. Cc: Len Brown Cc: Mark Salter Cc: "Rafael J. Wysocki" Signed-off-by: Matt Fleming --- drivers/firmware/efi/reboot.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/firmware/efi/reboot.c') diff --git a/drivers/firmware/efi/reboot.c b/drivers/firmware/efi/reboot.c index e9eeeb3c6345..9c59d1c795d1 100644 --- a/drivers/firmware/efi/reboot.c +++ b/drivers/firmware/efi/reboot.c @@ -5,6 +5,8 @@ #include #include +int efi_reboot_quirk_mode = -1; + void efi_reboot(enum reboot_mode reboot_mode, const char *__unused) { int efi_mode; @@ -22,6 +24,12 @@ void efi_reboot(enum reboot_mode reboot_mode, const char *__unused) break; } + /* + * If a quirk forced an EFI reset mode, always use that. + */ + if (efi_reboot_quirk_mode != -1) + efi_mode = efi_reboot_quirk_mode; + efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL); } -- cgit v1.2.3