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>
 *  Copyright (c) 2008 Intel Corporation
 *   Author: Matthew Wilcox <willy@linux.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/highmem.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/kmod.h>
#include <linux/delay.h>
#include <linux/workqueue.h>
#include <linux/nmi.h>
#include <linux/acpi.h>
#include <linux/acpi_io.h>
#include <linux/efi.h>
#include <linux/ioport.h>
#include <linux/list.h>
#include <linux/jiffies.h>
#include <linux/semaphore.h>

#include <asm/io.h>
#include <asm/uaccess.h>

#include <acpi/acpi.h>
#include <acpi/acpi_bus.h>
#include <acpi/processor.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;
	int wait;
};

#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 int (*__acpi_os_prepare_sleep)(u8 sleep_state, u32 pm1a_ctrl,
				      u32 pm1b_ctrl);

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;
struct workqueue_struct *kacpi_hotplug_wq;
EXPORT_SYMBOL(kacpi_hotplug_wq);

/*
 * This list of permanent mappings is for memory that may be accessed from
 * interrupt context, where we can't do the ioremap().
 */
struct acpi_ioremap {
	struct list_head list;
	void __iomem *virt;
	acpi_physical_address phys;
	acpi_size size;
	unsigned long refcount;
};

static LIST_HEAD(acpi_ioremaps);
static DEFINE_MUTEX(acpi_ioremap_lock);

static void __init acpi_osi_setup_late(void);

/*
 * The story of _OSI(Linux)
 *
 * From pre-history through Linux-2.6.22,
 * Linux responded TRUE upon a BIOS OSI(Linux) query.
 *
 * Unfortunately, reference BIOS writers got wind of this
 * and put OSI(Linux) in their example code, quickly exposing
 * this string as ill-conceived and opening the door to
 * an un-bounded number of BIOS incompatibilities.
 *
 * For example, OSI(Linux) was used on resume to re-POST a
 * video card on one system, because Linux at that time
 * could not do a speedy restore in its native driver.
 * But then upon gaining quick native restore capability,
 * Linux has no way to tell the BIOS to skip the time-consuming
 * POST -- putting Linux at a permanent performance disadvantage.
 * On another system, the BIOS writer used OSI(Linux)
 * to infer native OS support for IPMI!  On other systems,
 * OSI(Linux) simply got in the way of Linux claiming to
 * be compatible with other operating systems, exposing
 * BIOS issues such as skipped device initialization.
 *
 * So "Linux" turned out to be a really poor chose of
 * OSI string, and from Linux-2.6.23 onward we respond FALSE.
 *
 * BIOS writers should NOT query _OSI(Linux) on future systems.
 * Linux will complain on the console when it sees it, and return FALSE.
 * To get Linux to return TRUE for your system  will require
 * a kernel source update to add a DMI entry,
 * or boot with "acpi_osi=Linux"
 */

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

static u32 acpi_osi_handler(acpi_string interface, u32 supported)
{
	if (!strcmp("Linux", interface)) {

		printk_once(KERN_NOTICE FW_BUG PREFIX
			"BIOS _OSI(Linux) query %s%s\n",
			osi_linux.enable ? "honored" : "ignored",
			osi_linux.cmdline ? " via cmdline" :
			osi_linux.dmi ? " via DMI" : "");
	}

	return supported;
}

static void __init acpi_request_region (struct acpi_generic_address *gas,
	unsigned int length, char *desc)
{
	u64 addr;

	/* Handle possible alignment issues */
	memcpy(&addr, &gas->address, sizeof(addr));
	if (!addr || !length)
		return;

	/* Resources are never freed */
	if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
		request_region(addr, length, desc);
	else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
		request_mem_region(addr, length, desc);
}

static int __init acpi_reserve_resources(void)
{
	acpi_request_region(&acpi_gbl_FADT.xpm1a_event_block, acpi_gbl_FADT.pm1_event_length,
		"ACPI PM1a_EVT_BLK");

	acpi_request_region(&acpi_gbl_FADT.xpm1b_event_block, acpi_gbl_FADT