Return to acpi_pm.c CVS log

Up to [Development] / linux-2.6-xfs / drivers / clocksource

Update 2.6.x-xfs to 2.6.23-rc4.

Also update fs/xfs with external mainline changes.
There were 12 such missing commits that I detected:

--------
commit ad690ef9e690f6c31f7d310b09ef1314bcec9033
Author: Al Viro <viro@ftp.linux.org.uk>
    xfs ioctl __user annotations

commit 20c2df83d25c6a95affe6157a4c9cac4cf5ffaac
Author: Paul Mundt <lethal@linux-sh.org>
    mm: Remove slab destructors from kmem_cache_create().

commit d0217ac04ca6591841e5665f518e38064f4e65bd
Author: Nick Piggin <npiggin@suse.de>
    mm: fault feedback #1

commit 54cb8821de07f2ffcd28c380ce9b93d5784b40d7
Author: Nick Piggin <npiggin@suse.de>
    mm: merge populate and nopage into fault (fixes nonlinear)

commit d00806b183152af6d24f46f0c33f14162ca1262a
Author: Nick Piggin <npiggin@suse.de>
    mm: fix fault vs invalidate race for linear mappings

commit a569425512253992cc64ebf8b6d00a62f986db3e
Author: Christoph Hellwig <hch@infradead.org>
    knfsd: exportfs: add exportfs.h header

commit 831441862956fffa17b9801db37e6ea1650b0f69
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Freezer: make kernel threads nonfreezable by default

commit 8e1f936b73150f5095448a0fee6d4f30a1f9001d
Author: Rusty Russell <rusty@rustcorp.com.au>
    mm: clean up and kernelify shrinker registration

commit 5ffc4ef45b3b0a57872f631b4e4ceb8ace0d7496
Author: Jens Axboe <jens.axboe@oracle.com>
    sendfile: remove .sendfile from filesystems that use generic_file_sendfile()

commit 8bb7844286fb8c9fce6f65d8288aeb09d03a5e0d
Author: Rafael J. Wysocki <rjw@sisk.pl>
    Add suspend-related notifications for CPU hotplug

commit 59c51591a0ac7568824f541f57de967e88adaa07
Author: Michael Opdenacker <michael@free-electrons.com>
    Fix occurrences of "the the "

commit 0ceb331433e8aad9c5f441a965d7c681f8b9046f
Author: Dmitriy Monakhov <dmonakhov@openvz.org>
    mm: move common segment checks to separate helper function
--------
Merge of 2.6.x-xfs-melb:linux:29656b by kenmcd.

/*
 * linux/drivers/clocksource/acpi_pm.c
 *
 * This file contains the ACPI PM based clocksource.
 *
 * This code was largely moved from the i386 timer_pm.c file
 * which was (C) Dominik Brodowski <linux@brodo.de> 2003
 * and contained the following comments:
 *
 * Driver to use the Power Management Timer (PMTMR) available in some
 * southbridges as primary timing source for the Linux kernel.
 *
 * Based on parts of linux/drivers/acpi/hardware/hwtimer.c, timer_pit.c,
 * timer_hpet.c, and on Arjan van de Ven's implementation for 2.4.
 *
 * This file is licensed under the GPL v2.
 */

#include <linux/acpi_pmtmr.h>
#include <linux/clocksource.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <asm/io.h>

/*
 * The I/O port the PMTMR resides at.
 * The location is detected during setup_arch(),
 * in arch/i386/kernel/acpi/boot.c
 */
u32 pmtmr_ioport __read_mostly;

static inline u32 read_pmtmr(void)
{
	/* mask the output to 24 bits */
	return inl(pmtmr_ioport) & ACPI_PM_MASK;
}

u32 acpi_pm_read_verified(void)
{
	u32 v1 = 0, v2 = 0, v3 = 0;

	/*
	 * It has been reported that because of various broken
	 * chipsets (ICH4, PIIX4 and PIIX4E) where the ACPI PM clock
	 * source is not latched, you must read it multiple
	 * times to ensure a safe value is read:
	 */
	do {
		v1 = read_pmtmr();
		v2 = read_pmtmr();
		v3 = read_pmtmr();
	} while (unlikely((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
			  || (v3 > v1 && v3 < v2)));

	return v2;
}

static cycle_t acpi_pm_read_slow(void)
{
	return (cycle_t)acpi_pm_read_verified();
}

static cycle_t acpi_pm_read(void)
{
	return (cycle_t)read_pmtmr();
}

static struct clocksource clocksource_acpi_pm = {
	.name		= "acpi_pm",
	.rating		= 200,
	.read		= acpi_pm_read,
	.mask		= (cycle_t)ACPI_PM_MASK,
	.mult		= 0, /*to be calculated*/
	.shift		= 22,
	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,

};


#ifdef CONFIG_PCI
static int __devinitdata acpi_pm_good;
static int __init acpi_pm_good_setup(char *__str)
{
	acpi_pm_good = 1;
	return 1;
}
__setup("acpi_pm_good", acpi_pm_good_setup);

static inline void acpi_pm_need_workaround(void)
{
	clocksource_acpi_pm.read = acpi_pm_read_slow;
	clocksource_acpi_pm.rating = 120;
}

/*
 * PIIX4 Errata:
 *
 * The power management timer may return improper results when read.
 * Although the timer value settles properly after incrementing,
 * while incrementing there is a 3 ns window every 69.8 ns where the
 * timer value is indeterminate (a 4.2% chance that the data will be
 * incorrect when read). As a result, the ACPI free running count up
 * timer specification is violated due to erroneous reads.
 */
static void __devinit acpi_pm_check_blacklist(struct pci_dev *dev)
{
	if (acpi_pm_good)
		return;

	/* the bug has been fixed in PIIX4M */
	if (dev->revision < 3) {
		printk(KERN_WARNING "* Found PM-Timer Bug on the chipset."
		       " Due to workarounds for a bug,\n"
		       "* this clock source is slow. Consider trying"
		       " other clock sources\n");

		acpi_pm_need_workaround();
	}
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3,
			acpi_pm_check_blacklist);

static void __devinit acpi_pm_check_graylist(struct pci_dev *dev)
{
	if (acpi_pm_good)
		return;

	printk(KERN_WARNING "* The chipset may have PM-Timer Bug. Due to"
	       " workarounds for a bug,\n"
	       "* this clock source is slow. If you are sure your timer"
	       " does not have\n"
	       "* this bug, please use \"acpi_pm_good\" to disable the"
	       " workaround\n");

	acpi_pm_need_workaround();
}
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
			acpi_pm_check_graylist);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE,
			acpi_pm_check_graylist);
#endif

#ifndef CONFIG_X86_64
#include "mach_timer.h"
#define PMTMR_EXPECTED_RATE \
  ((CALIBRATE_LATCH * (PMTMR_TICKS_PER_SEC >> 10)) / (CLOCK_TICK_RATE>>10))
/*
 * Some boards have the PMTMR running way too fast. We check
 * the PMTMR rate against PIT channel 2 to catch these cases.
 */
static int verify_pmtmr_rate(void)
{
	u32 value1, value2;
	unsigned long count, delta;

	mach_prepare_counter();
	value1 = read_pmtmr();
	mach_countup(&count);
	value2 = read_pmtmr();
	delta = (value2 - value1) & ACPI_PM_MASK;

	/* Check that the PMTMR delta is within 5% of what we expect */
	if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
	    delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
		printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% "
			"of normal - aborting.\n",
			100UL * delta / PMTMR_EXPECTED_RATE);
		return -1;
	}

	return 0;
}
#else
#define verify_pmtmr_rate() (0)
#endif

static int __init init_acpi_pm_clocksource(void)
{
	u32 value1, value2;
	unsigned int i;

	if (!pmtmr_ioport)
		return -ENODEV;

	clocksource_acpi_pm.mult = clocksource_hz2mult(PMTMR_TICKS_PER_SEC,
						clocksource_acpi_pm.shift);

	/* "verify" this timing source: */
	value1 = read_pmtmr();
	for (i = 0; i < 10000; i++) {
		value2 = read_pmtmr();
		if (value2 == value1)
			continue;
		if (value2 > value1)
			goto pm_good;
		if ((value2 < value1) && ((value2) < 0xFFF))
			goto pm_good;
		printk(KERN_INFO "PM-Timer had inconsistent results:"
			" 0x%#x, 0x%#x - aborting.\n", value1, value2);
		return -EINVAL;
	}
	printk(KERN_INFO "PM-Timer had no reasonable result:"
			" 0x%#x - aborting.\n", value1);
	return -ENODEV;

pm_good:
	if (verify_pmtmr_rate() != 0)
		return -ENODEV;

	return clocksource_register(&clocksource_acpi_pm);
}

/* We use fs_initcall because we want the PCI fixups to have run
 * but we still need to load before device_initcall
 */
fs_initcall(init_acpi_pm_clocksource);