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Commit 4d387043 authored by Aaron Durbin's avatar Aaron Durbin Committed by Andi Kleen
Browse files

Add the ability to reset the machine using the RESET_REG in ACPI's FADT table. 



Signed-off-by: default avatarAaron Durbin <adurbin@google.com>
Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent c83642d5

drivers/acpi/Makefile

+1 −1
Original line number Original line Diff line number Diff line
@@ -21,7 +21,7 @@ obj-$(CONFIG_X86) += blacklist.o 
#

#

# ACPI Core Subsystem (Interpreter)

# ACPI Core Subsystem (Interpreter)

#

#

obj-y				+= osl.o utils.o \

obj-y				+= osl.o utils.o reboot.o\

				   dispatcher/ events/ executer/ hardware/ \

				   dispatcher/ events/ executer/ hardware/ \

				   namespace/ parser/ resources/ tables/ \

				   namespace/ parser/ resources/ tables/ \

				   utilities/

				   utilities/

drivers/acpi/reboot.c

0 → 100644
+50 −0
Original line number Original line Diff line number Diff line 


#include <linux/pci.h>

#include <linux/acpi.h>

#include <acpi/reboot.h>



void acpi_reboot(void)

{

	struct acpi_generic_address *rr;

	struct pci_bus *bus0;

	u8 reset_value;

	unsigned int devfn;



	if (acpi_disabled)

		return;



	rr = &acpi_gbl_FADT.reset_register;



	/* Is the reset register supported? */

	if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) ||

	    rr->bit_width != 8 || rr->bit_offset != 0)

		return;



	reset_value = acpi_gbl_FADT.reset_value;



	/* The reset register can only exist in I/O, Memory or PCI config space

	 * on a device on bus 0. */

	switch (rr->space_id) {

	case ACPI_ADR_SPACE_PCI_CONFIG:

		/* The reset register can only live on bus 0. */

		bus0 = pci_find_bus(0, 0);

		if (!bus0)

			return;

		/* Form PCI device/function pair. */

		devfn = PCI_DEVFN((rr->address >> 32) & 0xffff,

				  (rr->address >> 16) & 0xffff);

		printk(KERN_DEBUG "Resetting with ACPI PCI RESET_REG.");

		/* Write the value that resets us. */

		pci_bus_write_config_byte(bus0, devfn,

				(rr->address & 0xffff), reset_value);

		break;



	case ACPI_ADR_SPACE_SYSTEM_MEMORY:

	case ACPI_ADR_SPACE_SYSTEM_IO:

		printk(KERN_DEBUG "ACPI MEMORY or I/O RESET_REG.\n");

		acpi_hw_low_level_write(8, reset_value, rr);

		break;

	}

	/* Wait ten seconds */

	acpi_os_stall(10000000);

}

include/acpi/reboot.h

+8 −6
Original line number Original line Diff line number Diff line 
#ifndef __ACPI_REBOOT_H

#define __ACPI_REBOOT_H



#ifdef CONFIG_ACPI

extern void acpi_reboot(void);

#else

static inline void acpi_reboot(void) { }

#endif





/*

 * Dummy placeholder to make the EFI patches apply to the x86 tree.

 * Andrew/Len, please just kill this file if you encounter it.

 */

#ifndef acpi_reboot

# define acpi_reboot() do { } while (0)

#endif

#endif