path: root/drivers/acpi/osl.c

/*
 *  acpi_osl.c - OS-dependent functions ($Revision: 83 $)
 *
 *  Copyright (C) 2000       Andrew Henroid
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/dmi.h>
#include <linux/workqueue.h>
#include <linux/nmi.h>
#include <linux/acpi.h>
#include <acpi/acpi.h>
#include <asm/io.h>
#include <acpi/acpi_bus.h>
#include <acpi/processor.h>
#include <asm/uaccess.h>

#include <linux/efi.h>

#define _COMPONENT		ACPI_OS_SERVICES
ACPI_MODULE_NAME("osl");
#define PREFIX		"ACPI: "
struct acpi_os_dpc {
	acpi_osd_exec_callback function;
	void *context;
	struct work_struct work;
};

#ifdef CONFIG_ACPI_CUSTOM_DSDT
#include CONFIG_ACPI_CUSTOM_DSDT_FILE
#endif

#ifdef ENABLE_DEBUGGER
#include <linux/kdb.h>

/* stuff for debugger support */
int acpi_in_debugger;
EXPORT_SYMBOL(acpi_in_debugger);

extern char line_buf[80];
#endif				/*ENABLE_DEBUGGER */

static unsigned int acpi_irq_irq;
static acpi_osd_handler acpi_irq_handler;
static void *acpi_irq_context;
static struct workqueue_struct *kacpid_wq;
static struct workqueue_struct *kacpi_notify_wq;

#define	OSI_STRING_LENGTH_MAX 64	/* arbitrary */
static char osi_additional_string[OSI_STRING_LENGTH_MAX];

/*
 * "Ode to _OSI(Linux)"
 *
 * osi_linux -- Control response to BIOS _OSI(Linux) query.
 *
 * As Linux evolves, the features that it supports change.
 * So an OSI string such as "Linux" is not specific enough
 * to be useful across multiple versions of Linux.  It
 * doesn't identify any particular feature, interface,
 * or even any particular version of Linux...
 *
 * Unfortunately, Linux-2.6.22 and earlier responded "yes"
 * to a BIOS _OSI(Linux) query.  When
 * a reference mobile BIOS started using it, its use
 * started to spread to many vendor platforms.
 * As it is not supportable, we need to halt that spread.
 *
 * Today, most BIOS references to _OSI(Linux) are noise --
 * they have no functional effect and are just dead code
 * carried over from the reference BIOS.
 *
 * The next most common case is that _OSI(Linux) harms Linux,
 * usually by causing the BIOS to follow paths that are
 * not tested during Windows validation.
 *
 * Finally, there is a short list of platforms
 * where OSI(Linux) benefits Linux.
 *
 * In Linux-2.6.23, OSI(Linux) is first disabled by default.
 * DMI is used to disable the dmesg warning about OSI(Linux)
 * on platforms where it is known to have no effect.
 * But a dmesg warning remains for systems where
 * we do not know if OSI(Linux) is good or bad for the system.
 * DMI is also used to enable OSI(Linux) for the machines
 * that are known to need it.
 *
 * BIOS writers should NOT query _OSI(Linux) on future systems.
 * It will be ignored by default, and to get Linux to
 * not ignore it will require a kernel source update to
 * add a DMI entry, or a boot-time "acpi_osi=Linux" invocation.
 */
#define OSI_LINUX_ENABLE 0

static struct osi_linux {
	unsigned int	enable:1;
	unsigned int	dmi:1;
	unsigned int	cmdline:1;
	unsigned int	known:1;
} osi_linux = { OSI_LINUX_ENABLE, 0, 0, 0};

static void __init acpi_request_region (struct acpi_generic_address *addr,
	unsigned int length, char *desc)
{
	struct resource *res;

	if (!addr->address || !