b6a3780dad
Commit:
44be28e9dd98 ("x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag")
sets pm_power_off to efi_power_off() when the acpi_gbl_reduced_hardware
flag is set.
According to its commit message this is necessary because: "BayTrail-T
class of hardware requires EFI in order to powerdown and reboot and no
other reliable method exists".
But I have a Bay Trail CR tablet where the EFI_RESET_SHUTDOWN call does
not work, it simply returns without doing anything (AFAICT).
So it seems that some Bay Trail devices must use EFI for power-off, while
for others only ACPI works.
Note that efi_power_off() only gets used if the platform code defines
efi_poweroff_required() and that returns true, this currently only ever
happens on x86.
Since on the devices which need ACPI for power-off the EFI_RESET_SHUTDOWN
call simply returns, this patch makes the efi-reboot code remember the
old pm_power_off handler and if EFI_RESET_SHUTDOWN returns it falls back
to calling that.
This seems preferable to dmi-quirking our way out of this, since there
are likely quite a few devices suffering from this.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170818194947.19347-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
77 lines
1.7 KiB
C
77 lines
1.7 KiB
C
/*
|
|
* Copyright (C) 2014 Intel Corporation; author Matt Fleming
|
|
* Copyright (c) 2014 Red Hat, Inc., Mark Salter <msalter@redhat.com>
|
|
*/
|
|
#include <linux/efi.h>
|
|
#include <linux/reboot.h>
|
|
|
|
void (*orig_pm_power_off)(void);
|
|
|
|
int efi_reboot_quirk_mode = -1;
|
|
|
|
void efi_reboot(enum reboot_mode reboot_mode, const char *__unused)
|
|
{
|
|
const char *str[] = { "cold", "warm", "shutdown", "platform" };
|
|
int efi_mode, cap_reset_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;
|
|
}
|
|
|
|
/*
|
|
* If a quirk forced an EFI reset mode, always use that.
|
|
*/
|
|
if (efi_reboot_quirk_mode != -1)
|
|
efi_mode = efi_reboot_quirk_mode;
|
|
|
|
if (efi_capsule_pending(&cap_reset_mode)) {
|
|
if (efi_mode != cap_reset_mode)
|
|
printk(KERN_CRIT "efi: %s reset requested but pending "
|
|
"capsule update requires %s reset... Performing "
|
|
"%s reset.\n", str[efi_mode], str[cap_reset_mode],
|
|
str[cap_reset_mode]);
|
|
efi_mode = cap_reset_mode;
|
|
}
|
|
|
|
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);
|
|
/*
|
|
* The above call should not return, if it does fall back to
|
|
* the original power off method (typically ACPI poweroff).
|
|
*/
|
|
if (orig_pm_power_off)
|
|
orig_pm_power_off();
|
|
}
|
|
|
|
static int __init efi_shutdown_init(void)
|
|
{
|
|
if (!efi_enabled(EFI_RUNTIME_SERVICES))
|
|
return -ENODEV;
|
|
|
|
if (efi_poweroff_required()) {
|
|
orig_pm_power_off = pm_power_off;
|
|
pm_power_off = efi_power_off;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
late_initcall(efi_shutdown_init);
|