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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [acpi/] [processor.c] - Blame information for rev 1774

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/*
 * acpi_processor.c - ACPI Processor Driver ($Revision: 1.1.1.1 $)
 *
 *  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.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *  TBD:
 *      1. Make # power/performance states dynamic.
 *      2. Support duty_cycle values that span bit 4.
 *      3. Optimize by having scheduler determine business instead of
 *         having us try to calculate it here.
 *      4. Need C1 timing -- must modify kernel (IRQ handler) to get this.
 */
 
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pm.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/delay.h>
#include <linux/compatmac.h>
#include <linux/proc_fs.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
 
 
#define _COMPONENT              ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME                ("acpi_processor")
 
MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION(ACPI_PROCESSOR_DRIVER_NAME);
MODULE_LICENSE("GPL");
 
#define PREFIX                          "ACPI: "
 
#define US_TO_PM_TIMER_TICKS(t)         ((t * (PM_TIMER_FREQUENCY/1000)) / 1000)
#define C2_OVERHEAD                     4       /* 1us (3.579 ticks per us) */
#define C3_OVERHEAD                     4       /* 1us (3.579 ticks per us) */
 
#define ACPI_PROCESSOR_BUSY_METRIC      10
 
#define ACPI_PROCESSOR_MAX_POWER        ACPI_C_STATE_COUNT
#define ACPI_PROCESSOR_MAX_C2_LATENCY   100
#define ACPI_PROCESSOR_MAX_C3_LATENCY   1000
 
#define ACPI_PROCESSOR_MAX_PERFORMANCE  8
 
#define ACPI_PROCESSOR_MAX_THROTTLING   16
#define ACPI_PROCESSOR_MAX_THROTTLE     250     /* 25% */
#define ACPI_PROCESSOR_MAX_DUTY_WIDTH   4
 
#define ACPI_PROCESSOR_LIMIT_USER       0
#define ACPI_PROCESSOR_LIMIT_THERMAL    1
 
static int acpi_processor_add (struct acpi_device *device);
static int acpi_processor_remove (struct acpi_device *device, int type);
 
static struct acpi_driver acpi_processor_driver = {
        .name =         ACPI_PROCESSOR_DRIVER_NAME,
        .class =        ACPI_PROCESSOR_CLASS,
        .ids =          ACPI_PROCESSOR_HID,
        .ops =          {
                                .add =          acpi_processor_add,
                                .remove =       acpi_processor_remove,
                        },
};
 
/* Power Management */
 
struct acpi_processor_cx_policy {
        u32                     count;
        int                     state;
        struct {
                u32                     time;
                u32                     ticks;
                u32                     count;
                u32                     bm;
        }                       threshold;
};
 
struct acpi_processor_cx {
        u8                      valid;
        u32                     address;
        u32                     latency;
        u32                     latency_ticks;
        u32                     power;
        u32                     usage;
        struct acpi_processor_cx_policy promotion;
        struct acpi_processor_cx_policy demotion;
};
 
struct acpi_processor_power {
        int                     state;
        int                     default_state;
        u32                     bm_activity;
        struct acpi_processor_cx states[ACPI_PROCESSOR_MAX_POWER];
};
 
/* Performance Management */
 
struct acpi_pct_register {
        u8                      descriptor;
        u16                     length;
        u8                      space_id;
        u8                      bit_width;
        u8                      bit_offset;
        u8                      reserved;
        u64                     address;
} __attribute__ ((packed));
 
struct acpi_processor_px {
        acpi_integer            core_frequency;         /* megahertz */
        acpi_integer            power;                  /* milliWatts */
        acpi_integer            transition_latency;     /* microseconds */
        acpi_integer            bus_master_latency;     /* microseconds */
        acpi_integer            control;                /* control value */
        acpi_integer            status;                 /* success indicator */
};
 
struct acpi_processor_performance {
        int                     state;
        int                     platform_limit;
        u16                     control_register;
        u16                     status_register;
        u8                      control_register_bit_width;
        u8                      status_register_bit_width;
        int                     state_count;
        struct acpi_processor_px states[ACPI_PROCESSOR_MAX_PERFORMANCE];
};
 
 
/* Throttling Control */
 
struct acpi_processor_tx {
        u16                     power;
        u16                     performance;
};
 
struct acpi_processor_throttling {
        int                     state;
        u32                     address;
        u8                      duty_offset;
        u8                      duty_width;
        int                     state_count;
        struct acpi_processor_tx states[ACPI_PROCESSOR_MAX_THROTTLING];
};
 
/* Limit Interface */
 
struct acpi_processor_lx {
        int                     px;             /* performace state */
        int                     tx;             /* throttle level */
};
 
struct acpi_processor_limit {
        struct acpi_processor_lx state;         /* current limit */
        struct acpi_processor_lx thermal;       /* thermal limit */
        struct acpi_processor_lx user;          /* user limit */
};
 
 
struct acpi_processor_flags {
        u8                      power:1;
        u8                      performance:1;
        u8                      throttling:1;
        u8                      limit:1;
        u8                      bm_control:1;
        u8                      bm_check:1;
        u8                      reserved:2;
};
 
struct acpi_processor {
        acpi_handle             handle;
        u32                     acpi_id;
        u32                     id;
        struct acpi_processor_flags flags;
        struct acpi_processor_power power;
        struct acpi_processor_performance performance;
        struct acpi_processor_throttling throttling;
        struct acpi_processor_limit limit;
};
 
struct acpi_processor_errata {
        u8                      smp;
        struct {
                u8                      throttle:1;
                u8                      fdma:1;
                u8                      reserved:6;
                u32                     bmisx;
        }                       piix4;
};
 
static struct acpi_processor    *processors[NR_CPUS];
static struct acpi_processor_errata errata;
static void (*pm_idle_save)(void);
 
 
/* --------------------------------------------------------------------------
                                Errata Handling
   -------------------------------------------------------------------------- */
 
int
acpi_processor_errata_piix4 (
        struct pci_dev          *dev)
{
        u8                      rev = 0;
        u8                      value1 = 0;
        u8                      value2 = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_errata_piix4");
 
        if (!dev)
                return_VALUE(-EINVAL);
 
        /*
         * Note that 'dev' references the PIIX4 ACPI Controller.
         */
 
        pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
 
        switch (rev) {
        case 0:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
                break;
        case 1:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
                break;
        case 2:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
                break;
        case 3:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
                break;
        default:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
                break;
        }
 
        switch (rev) {
 
        case 0:          /* PIIX4 A-step */
        case 1:         /* PIIX4 B-step */
                /*
                 * See specification changes #13 ("Manual Throttle Duty Cycle")
                 * and #14 ("Enabling and Disabling Manual Throttle"), plus
                 * erratum #5 ("STPCLK# Deassertion Time") from the January
                 * 2002 PIIX4 specification update.  Applies to only older
                 * PIIX4 models.
                 */
                errata.piix4.throttle = 1;
 
        case 2:         /* PIIX4E */
        case 3:         /* PIIX4M */
                /*
                 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
                 * Livelock") from the January 2002 PIIX4 specification update.
                 * Applies to all PIIX4 models.
                 */
 
                /*
                 * BM-IDE
                 * ------
                 * Find the PIIX4 IDE Controller and get the Bus Master IDE
                 * Status register address.  We'll use this later to read
                 * each IDE controller's DMA status to make sure we catch all
                 * DMA activity.
                 */
                dev = pci_find_subsys(PCI_VENDOR_ID_INTEL,
                           PCI_DEVICE_ID_INTEL_82371AB,
                           PCI_ANY_ID, PCI_ANY_ID, NULL);
                if (dev)
                        errata.piix4.bmisx = pci_resource_start(dev, 4);
 
                /*
                 * Type-F DMA
                 * ----------
                 * Find the PIIX4 ISA Controller and read the Motherboard
                 * DMA controller's status to see if Type-F (Fast) DMA mode
                 * is enabled (bit 7) on either channel.  Note that we'll
                 * disable C3 support if this is enabled, as some legacy
                 * devices won't operate well if fast DMA is disabled.
                 */
                dev = pci_find_subsys(PCI_VENDOR_ID_INTEL,
                        PCI_DEVICE_ID_INTEL_82371AB_0,
                        PCI_ANY_ID, PCI_ANY_ID, NULL);
                if (dev) {
                        pci_read_config_byte(dev, 0x76, &value1);
                        pci_read_config_byte(dev, 0x77, &value2);
                        if ((value1 & 0x80) || (value2 & 0x80))
                                errata.piix4.fdma = 1;
                }
 
                break;
        }
 
        if (errata.piix4.bmisx)
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Bus master activity detection (BM-IDE) erratum enabled\n"));
        if (errata.piix4.fdma)
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Type-F DMA livelock erratum (C3 disabled)\n"));
 
        return_VALUE(0);
}
 
 
int
acpi_processor_errata (
        struct acpi_processor   *pr)
{
        int                     result = 0;
        struct pci_dev          *dev = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_errata");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        /*
         * PIIX4
         */
        dev = pci_find_subsys(PCI_VENDOR_ID_INTEL,
                PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, PCI_ANY_ID, NULL);
        if (dev)
                result = acpi_processor_errata_piix4(dev);
 
        return_VALUE(result);
}
 
 
/* --------------------------------------------------------------------------
                                Power Management
   -------------------------------------------------------------------------- */
 
static inline u32
ticks_elapsed (
        u32                     t1,
        u32                     t2)
{
        if (t2 >= t1)
                return (t2 - t1);
        else if (!acpi_fadt.tmr_val_ext)
                return (((0x00FFFFFF - t1) + t2) & 0x00FFFFFF);
        else
                return ((0xFFFFFFFF - t1) + t2);
}
 
 
static void
acpi_processor_power_activate (
        struct acpi_processor   *pr,
        int                     state)
{
        if (!pr)
                return;
 
        pr->power.states[pr->power.state].promotion.count = 0;
        pr->power.states[pr->power.state].demotion.count = 0;
 
        /* Cleanup from old state. */
        switch (pr->power.state) {
        case ACPI_STATE_C3:
                /* Disable bus master reload */
                acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 0, ACPI_MTX_DO_NOT_LOCK);
                break;
        }
 
        /* Prepare to use new state. */
        switch (state) {
        case ACPI_STATE_C3:
                /* Enable bus master reload */
                acpi_set_register(ACPI_BITREG_BUS_MASTER_RLD, 1, ACPI_MTX_DO_NOT_LOCK);
                break;
        }
 
        pr->power.state = state;
 
        return;
}
 
 
static void
acpi_processor_idle (void)
{
        struct acpi_processor   *pr = NULL;
        struct acpi_processor_cx *cx = NULL;
        int                     next_state = 0;
        int                     sleep_ticks = 0;
        u32                     t1, t2 = 0;
 
        pr = processors[smp_processor_id()];
        if (!pr)
                return;
 
        /*
         * Interrupts must be disabled during bus mastering calculations and
         * for C2/C3 transitions.
         */
        __cli();
 
        cx = &(pr->power.states[pr->power.state]);
 
        /*
         * Check BM Activity
         * -----------------
         * Check for bus mastering activity (if required), record, and check
         * for demotion.
         */
        if (pr->flags.bm_check) {
                u32             bm_status = 0;
 
                pr->power.bm_activity <<= 1;
 
                acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS,
                        &bm_status, ACPI_MTX_DO_NOT_LOCK);
                if (bm_status) {
                        pr->power.bm_activity++;
                        acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS,
                                1, ACPI_MTX_DO_NOT_LOCK);
                }
                /*
                 * PIIX4 Erratum #18: Note that BM_STS doesn't always reflect
                 * the true state of bus mastering activity; forcing us to
                 * manually check the BMIDEA bit of each IDE channel.
                 */
                else if (errata.piix4.bmisx) {
                        if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
                                || (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
                                pr->power.bm_activity++;
                }
                /*
                 * Apply bus mastering demotion policy.  Automatically demote
                 * to avoid a faulty transition.  Note that the processor
                 * won't enter a low-power state during this call (to this
                 * funciton) but should upon the next.
                 *
                 * TBD: A better policy might be to fallback to the demotion
                 *      state (use it for this quantum only) istead of
                 *      demoting -- and rely on duration as our sole demotion
                 *      qualification.  This may, however, introduce DMA
                 *      issues (e.g. floppy DMA transfer overrun/underrun).
                 */
                if (pr->power.bm_activity & cx->demotion.threshold.bm) {
                        __sti();
                        next_state = cx->demotion.state;
                        goto end;
                }
        }
 
        cx->usage++;
 
        /*
         * Sleep:
         * ------
         * Invoke the current Cx state to put the processor to sleep.
         */
        switch (pr->power.state) {
 
        case ACPI_STATE_C1:
                /* Invoke C1. */
                safe_halt();
                /*
                 * TBD: Can't get time duration while in C1, as resumes
                 *      go to an ISR rather than here.  Need to instrument
                 *      base interrupt handler.
                 */
                sleep_ticks = 0xFFFFFFFF;
                break;
 
        case ACPI_STATE_C2:
                /* Get start time (ticks) */
                t1 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Invoke C2 */
                inb(pr->power.states[ACPI_STATE_C2].address);
                /* Dummy op - must do something useless after P_LVL2 read */
                t2 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Get end time (ticks) */
                t2 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Re-enable interrupts */
                __sti();
                /* Compute time (ticks) that we were actually asleep */
                sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD;
                break;
 
        case ACPI_STATE_C3:
                /* Disable bus master arbitration */
                acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1, ACPI_MTX_DO_NOT_LOCK);
                /* Get start time (ticks) */
                t1 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Invoke C3 */
                inb(pr->power.states[ACPI_STATE_C3].address);
                /* Dummy op - must do something useless after P_LVL3 read */
                t2 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Get end time (ticks) */
                t2 = inl(acpi_fadt.xpm_tmr_blk.address);
                /* Enable bus master arbitration */
                acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0, ACPI_MTX_DO_NOT_LOCK);
                /* Re-enable interrupts */
                __sti();
                /* Compute time (ticks) that we were actually asleep */
                sleep_ticks = ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD;
                break;
 
        default:
                __sti();
                return;
        }
 
        next_state = pr->power.state;
 
        /*
         * Promotion?
         * ----------
         * Track the number of longs (time asleep is greater than threshold)
         * and promote when the count threshold is reached.  Note that bus
         * mastering activity may prevent promotions.
         */
        if (cx->promotion.state) {
                if (sleep_ticks > cx->promotion.threshold.ticks) {
                        cx->promotion.count++;
                        cx->demotion.count = 0;
                        if (cx->promotion.count >= cx->promotion.threshold.count) {
                                if (pr->flags.bm_check) {
                                        if (!(pr->power.bm_activity & cx->promotion.threshold.bm)) {
                                                next_state = cx->promotion.state;
                                                goto end;
                                        }
                                }
                                else {
                                        next_state = cx->promotion.state;
                                        goto end;
                                }
                        }
                }
        }
 
        /*
         * Demotion?
         * ---------
         * Track the number of shorts (time asleep is less than time threshold)
         * and demote when the usage threshold is reached.
         */
        if (cx->demotion.state) {
                if (sleep_ticks < cx->demotion.threshold.ticks) {
                        cx->demotion.count++;
                        cx->promotion.count = 0;
                        if (cx->demotion.count >= cx->demotion.threshold.count) {
                                next_state = cx->demotion.state;
                                goto end;
                        }
                }
        }
 
end:
        /*
         * New Cx State?
         * -------------
         * If we're going to start using a new Cx state we must clean up
         * from the previous and prepare to use the new.
         */
        if (next_state != pr->power.state)
                acpi_processor_power_activate(pr, next_state);
 
        return;
}
 
 
static int
acpi_processor_set_power_policy (
        struct acpi_processor   *pr)
{
        ACPI_FUNCTION_TRACE("acpi_processor_set_power_policy");
 
        /*
         * This function sets the default Cx state policy (OS idle handler).
         * Our scheme is to promote quickly to C2 but more conservatively
         * to C3.  We're favoring C2  for its characteristics of low latency
         * (quick response), good power savings, and ability to allow bus
         * mastering activity.  Note that the Cx state policy is completely
         * customizable and can be altered dynamically.
         */
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        /*
         * C0/C1
         * -----
         */
        pr->power.state = ACPI_STATE_C1;
        pr->power.default_state = ACPI_STATE_C1;
 
        /*
         * C1/C2
         * -----
         * Set the default C1 promotion and C2 demotion policies, where we
         * promote from C1 to C2 after several (10) successive C1 transitions,
         * as we cannot (currently) measure the time spent in C1. Demote from
         * C2 to C1 anytime we experience a 'short' (time spent in C2 is less
         * than the C2 transtion latency).  Note the simplifying assumption
         * that the 'cost' of a transition is amortized when we sleep for at
         * least as long as the transition's latency (thus the total transition
         * time is two times the latency).
         *
         * TBD: Measure C1 sleep times by instrumenting the core IRQ handler.
         * TBD: Demote to default C-State after long periods of activity.
         * TBD: Investigate policy's use of CPU utilization -vs- sleep duration.
         */
        if (pr->power.states[ACPI_STATE_C2].valid) {
                pr->power.states[ACPI_STATE_C1].promotion.threshold.count = 10;
                pr->power.states[ACPI_STATE_C1].promotion.threshold.ticks =
                        pr->power.states[ACPI_STATE_C2].latency_ticks;
                pr->power.states[ACPI_STATE_C1].promotion.state = ACPI_STATE_C2;
 
                pr->power.states[ACPI_STATE_C2].demotion.threshold.count = 1;
                pr->power.states[ACPI_STATE_C2].demotion.threshold.ticks =
                        pr->power.states[ACPI_STATE_C2].latency_ticks;
                pr->power.states[ACPI_STATE_C2].demotion.state = ACPI_STATE_C1;
        }
 
        /*
         * C2/C3
         * -----
         * Set default C2 promotion and C3 demotion policies, where we promote
         * from C2 to C3 after several (4) cycles of no bus mastering activity
         * while maintaining sleep time criteria.  Demote immediately on a
         * short or whenever bus mastering activity occurs.
         */
        if ((pr->power.states[ACPI_STATE_C2].valid) &&
                (pr->power.states[ACPI_STATE_C3].valid)) {
                pr->power.states[ACPI_STATE_C2].promotion.threshold.count = 4;
                pr->power.states[ACPI_STATE_C2].promotion.threshold.ticks =
                        pr->power.states[ACPI_STATE_C3].latency_ticks;
                pr->power.states[ACPI_STATE_C2].promotion.threshold.bm = 0x0F;
                pr->power.states[ACPI_STATE_C2].promotion.state = ACPI_STATE_C3;
 
                pr->power.states[ACPI_STATE_C3].demotion.threshold.count = 1;
                pr->power.states[ACPI_STATE_C3].demotion.threshold.ticks =
                        pr->power.states[ACPI_STATE_C3].latency_ticks;
                pr->power.states[ACPI_STATE_C3].demotion.threshold.bm = 0x0F;
                pr->power.states[ACPI_STATE_C3].demotion.state = ACPI_STATE_C2;
        }
 
        return_VALUE(0);
}
 
 
int
acpi_processor_get_power_info (
        struct acpi_processor   *pr)
{
        int                     result = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_power_info");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "lvl2[0x%08x] lvl3[0x%08x]\n",
                pr->power.states[ACPI_STATE_C2].address,
                pr->power.states[ACPI_STATE_C3].address));
 
        /* TBD: Support ACPI 2.0 objects */
 
        /*
         * C0
         * --
         * This state exists only as filler in our array.
         */
        pr->power.states[ACPI_STATE_C0].valid = 1;
 
        /*
         * C1
         * --
         * ACPI requires C1 support for all processors.
         *
         * TBD: What about PROC_C1?
         */
        pr->power.states[ACPI_STATE_C1].valid = 1;
 
        /*
         * C2
         * --
         * We're (currently) only supporting C2 on UP systems.
         *
         * TBD: Support for C2 on MP (P_LVL2_UP).
         */
        if (pr->power.states[ACPI_STATE_C2].address) {
 
                pr->power.states[ACPI_STATE_C2].latency = acpi_fadt.plvl2_lat;
 
                /*
                 * C2 latency must be less than or equal to 100 microseconds.
                 */
                if (acpi_fadt.plvl2_lat > ACPI_PROCESSOR_MAX_C2_LATENCY)
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C2 latency too large [%d]\n",
                                acpi_fadt.plvl2_lat));
                /*
                 * Only support C2 on UP systems (see TBD above).
                 */
                else if (errata.smp)
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C2 not supported in SMP mode\n"));
                /*
                 * Otherwise we've met all of our C2 requirements.
                 * Normalize the C2 latency to expidite policy.
                 */
                else {
                        pr->power.states[ACPI_STATE_C2].valid = 1;
                        pr->power.states[ACPI_STATE_C2].latency_ticks =
                                US_TO_PM_TIMER_TICKS(acpi_fadt.plvl2_lat);
                }
        }
 
        /*
         * C3
         * --
         * TBD: Investigate use of WBINVD on UP/SMP system in absence of
         *      bm_control.
         */
        if (pr->power.states[ACPI_STATE_C3].address) {
 
                pr->power.states[ACPI_STATE_C3].latency = acpi_fadt.plvl3_lat;
 
                /*
                 * C3 latency must be less than or equal to 1000 microseconds.
                 */
                if (acpi_fadt.plvl3_lat > ACPI_PROCESSOR_MAX_C3_LATENCY)
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C3 latency too large [%d]\n",
                                acpi_fadt.plvl3_lat));
                /*
                 * Only support C3 when bus mastering arbitration control
                 * is present (able to disable bus mastering to maintain
                 * cache coherency while in C3).
                 */
                else if (!pr->flags.bm_control)
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C3 support requires bus mastering control\n"));
                /*
                 * Only support C3 on UP systems, as bm_control is only viable
                 * on a UP system and flushing caches (e.g. WBINVD) is simply
                 * too costly (at this time).
                 */
                else if (errata.smp)
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C3 not supported in SMP mode\n"));
                /*
                 * PIIX4 Erratum #18: We don't support C3 when Type-F (fast)
                 * DMA transfers are used by any ISA device to avoid livelock.
                 * Note that we could disable Type-F DMA (as recommended by
                 * the erratum), but this is known to disrupt certain ISA
                 * devices thus we take the conservative approach.
                 */
                else if (errata.piix4.fdma) {
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                "C3 not supported on PIIX4 with Type-F DMA\n"));
                }
                /*
                 * Otherwise we've met all of our C3 requirements.
                 * Normalize the C2 latency to expidite policy.  Enable
                 * checking of bus mastering status (bm_check) so we can
                 * use this in our C3 policy.
                 */
                else {
                        pr->power.states[ACPI_STATE_C3].valid = 1;
                        pr->power.states[ACPI_STATE_C3].latency_ticks =
                                US_TO_PM_TIMER_TICKS(acpi_fadt.plvl3_lat);
                        pr->flags.bm_check = 1;
                }
        }
 
        /*
         * Set Default Policy
         * ------------------
         * Now that we know which state are supported, set the default
         * policy.  Note that this policy can be changed dynamically
         * (e.g. encourage deeper sleeps to conserve battery life when
         * not on AC).
         */
        result = acpi_processor_set_power_policy(pr);
        if (result)
                return_VALUE(result);
 
        /*
         * If this processor supports C2 or C3 we denote it as being 'power
         * manageable'.  Note that there's really no policy involved for
         * when only C1 is supported.
         */
        if (pr->power.states[ACPI_STATE_C2].valid
                || pr->power.states[ACPI_STATE_C3].valid)
                pr->flags.power = 1;
 
        return_VALUE(0);
}
 
 
/* --------------------------------------------------------------------------
                              Performance Management
   -------------------------------------------------------------------------- */
 
static int
acpi_processor_get_platform_limit (
        struct acpi_processor*  pr)
{
        acpi_status             status = 0;
        unsigned long           ppc = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_platform_limit");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        /*
         * _PPC indicates the maximum state currently supported by the platform
         * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
         */
        status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
        if(ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PPC\n"));
                return_VALUE(-ENODEV);
        }
 
        pr->performance.platform_limit = (int) ppc;
 
        return_VALUE(0);
}
 
 
static int
acpi_processor_get_performance_control (
        struct acpi_processor   *pr)
{
        int                     result = 0;
        acpi_status             status = 0;
        struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
        union acpi_object       *pct = NULL;
        union acpi_object       obj = {0};
        struct acpi_pct_register *reg = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_performance_control");
 
        status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
        if(ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PCT\n"));
                return_VALUE(-ENODEV);
        }
 
        pct = (union acpi_object *) buffer.pointer;
        if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
                || (pct->package.count != 2)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data\n"));
                result = -EFAULT;
                goto end;
        }
 
        /*
         * control_register
         */
 
        obj = pct->package.elements[0];
 
        if ((obj.type != ACPI_TYPE_BUFFER)
                || (obj.buffer.length < sizeof(struct acpi_pct_register))
                || (obj.buffer.pointer == NULL)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Invalid _PCT data (control_register)\n"));
                result = -EFAULT;
                goto end;
        }
 
        reg = (struct acpi_pct_register *) (obj.buffer.pointer);
 
        if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unsupported address space [%d] (control_register)\n",
                        (u32) reg->space_id));
                result = -EFAULT;
                goto end;
        }
 
        pr->performance.control_register = (u16) reg->address;
        pr->performance.control_register_bit_width = reg->bit_width;
        /*
         * status_register
         */
 
        obj = pct->package.elements[1];
 
        if ((obj.type != ACPI_TYPE_BUFFER)
                || (obj.buffer.length < sizeof(struct acpi_pct_register))
                || (obj.buffer.pointer == NULL)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Invalid _PCT data (status_register)\n"));
                result = -EFAULT;
                goto end;
        }
 
        reg = (struct acpi_pct_register *) (obj.buffer.pointer);
 
        if (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unsupported address space [%d] (status_register)\n",
                        (u32) reg->space_id));
                result = -EFAULT;
                goto end;
        }
 
        pr->performance.status_register = (u16) reg->address;
        pr->performance.status_register_bit_width = reg->bit_width;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "control_register[0x%04x] status_register[0x%04x]\n",
                pr->performance.control_register,
                pr->performance.status_register));
 
end:
        acpi_os_free(buffer.pointer);
 
        return_VALUE(result);
}
 
 
static int
acpi_processor_get_performance_states (
        struct acpi_processor*  pr)
{
        int                     result = 0;
        acpi_status             status = AE_OK;
        struct acpi_buffer      buffer = {ACPI_ALLOCATE_BUFFER, NULL};
        struct acpi_buffer      format = {sizeof("NNNNNN"), "NNNNNN"};
        struct acpi_buffer      state = {0, NULL};
        union acpi_object       *pss = NULL;
        int                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_performance_states");
 
        status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
        if(ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PSS\n"));
                return_VALUE(-ENODEV);
        }
 
        pss = (union acpi_object *) buffer.pointer;
        if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
                result = -EFAULT;
                goto end;
        }
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
                pss->package.count));
 
        if (pss->package.count > ACPI_PROCESSOR_MAX_PERFORMANCE) {
                pr->performance.state_count = ACPI_PROCESSOR_MAX_PERFORMANCE;
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Limiting number of states to max (%d)\n",
                        ACPI_PROCESSOR_MAX_PERFORMANCE));
        }
        else
                pr->performance.state_count = pss->package.count;
 
        if (pr->performance.state_count > 1)
                pr->flags.performance = 1;
 
        for (i = 0; i < pr->performance.state_count; i++) {
 
                struct acpi_processor_px *px = &(pr->performance.states[i]);
 
                state.length = sizeof(struct acpi_processor_px);
                state.pointer = px;
 
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));
 
                status = acpi_extract_package(&(pss->package.elements[i]),
                        &format, &state);
                if (ACPI_FAILURE(status)) {
                        ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
                        result = -EFAULT;
                        goto end;
                }
 
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
                        i,
                        (u32) px->core_frequency,
                        (u32) px->power,
                        (u32) px->transition_latency,
                        (u32) px->bus_master_latency,
                        (u32) px->control,
                        (u32) px->status));
        }
 
end:
        acpi_os_free(buffer.pointer);
 
        return_VALUE(result);
}
 
static int
acpi_processor_write_port(
        u16     port,
        u8      bit_width,
        u32     value)
{
        if (bit_width <= 8) {
                outb(value, port);
        } else if (bit_width <= 16) {
                outw(value, port);
        } else if (bit_width <= 32) {
                outl(value, port);
        } else {
                return -ENODEV;
        }
        return 0;
}
 
static int
acpi_processor_read_port(
        u16     port,
        u8      bit_width,
        u32     *ret)
{
        *ret = 0;
        if (bit_width <= 8) {
                *ret = inb(port);
        } else if (bit_width <= 16) {
                *ret = inw(port);
        } else if (bit_width <= 32) {
                *ret = inl(port);
        } else {
                return -ENODEV;
        }
        return 0;
}
 
static int
acpi_processor_set_performance (
        struct acpi_processor   *pr,
        int                     state)
{
        u16                     port = 0;
        u8                      bit_width = 0;
        int                     ret = 0;
        u32                     value = 0;
        int                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_set_performance");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        if (!pr->flags.performance)
                return_VALUE(-ENODEV);
 
        if (state >= pr->performance.state_count) {
                ACPI_DEBUG_PRINT((ACPI_DB_WARN,
                        "Invalid target state (P%d)\n", state));
                return_VALUE(-ENODEV);
        }
 
        if (state < pr->performance.platform_limit) {
                ACPI_DEBUG_PRINT((ACPI_DB_WARN,
                        "Platform limit (P%d) overrides target state (P%d)\n",
                        pr->performance.platform_limit, state));
                return_VALUE(-ENODEV);
        }
 
        if (state == pr->performance.state) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Already at target state (P%d)\n", state));
                return_VALUE(0);
        }
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Transitioning from P%d to P%d\n",
                pr->performance.state, state));
 
        /*
         * First we write the target state's 'control' value to the
         * control_register.
         */
 
        port = pr->performance.control_register;
        value = (u32) pr->performance.states[state].control;
        bit_width = pr->performance.control_register_bit_width;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Writing 0x%08x to port 0x%04x\n", value, port));
 
        ret = acpi_processor_write_port(port, bit_width, value);
        if (ret) {
                ACPI_DEBUG_PRINT((ACPI_DB_WARN,
                        "Invalid port width 0x%04x\n", bit_width));
                return_VALUE(ret);
        }
 
        /*
         * Then we read the 'status_register' and compare the value with the
         * target state's 'status' to make sure the transition was successful.
         * Note that we'll poll for up to 1ms (100 cycles of 10us) before
         * giving up.
         */
 
        port = pr->performance.status_register;
        bit_width = pr->performance.status_register_bit_width;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Looking for 0x%08x from port 0x%04x\n",
                (u32) pr->performance.states[state].status, port));
 
        for (i=0; i<100; i++) {
                ret = acpi_processor_read_port(port, bit_width, &value);
                if (ret) {
                        ACPI_DEBUG_PRINT((ACPI_DB_WARN,
                                "Invalid port width 0x%04x\n", bit_width));
                        return_VALUE(ret);
                }
                if (value == (u32) pr->performance.states[state].status)
                        break;
                udelay(10);
        }
 
        if (value != (u32) pr->performance.states[state].status) {
                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Transition failed\n"));
                return_VALUE(-ENODEV);
        }
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Transition successful after %d microseconds\n",
                i * 10));
 
        pr->performance.state = state;
 
        return_VALUE(0);
}
 
 
static int
acpi_processor_get_performance_info (
        struct acpi_processor   *pr)
{
        int                     result = 0;
        acpi_status             status = AE_OK;
        acpi_handle             handle = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        status = acpi_get_handle(pr->handle, "_PCT", &handle);
        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "ACPI-based processor performance control unavailable\n"));
                return_VALUE(0);
        }
 
        result = acpi_processor_get_performance_control(pr);
        if (result)
                return_VALUE(result);
 
        result = acpi_processor_get_performance_states(pr);
        if (result)
                return_VALUE(result);
 
        result = acpi_processor_get_platform_limit(pr);
        if (result)
                return_VALUE(result);
 
        /*
         * TBD: Don't trust the latency values we get from BIOS, but rather
         *      measure the latencies during run-time (e.g. get_latencies).
         */
 
        return_VALUE(0);
}
 
 
/* --------------------------------------------------------------------------
                              Throttling Control
   -------------------------------------------------------------------------- */
 
static int
acpi_processor_get_throttling (
        struct acpi_processor   *pr)
{
        int                     state = 0;
        u32                     value = 0;
        u32                     duty_mask = 0;
        u32                     duty_value = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_throttling");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        if (!pr->flags.throttling)
                return_VALUE(-ENODEV);
 
        pr->throttling.state = 0;
 
        __cli();
 
        duty_mask = pr->throttling.state_count - 1;
 
        duty_mask <<= pr->throttling.duty_offset;
 
        value = inl(pr->throttling.address);
 
        /*
         * Compute the current throttling state when throttling is enabled
         * (bit 4 is on).
         */
        if (value & 0x10) {
                duty_value = value & duty_mask;
                duty_value >>= pr->throttling.duty_offset;
 
                if (duty_value)
                        state = pr->throttling.state_count-duty_value;
        }
 
        pr->throttling.state = state;
 
        __sti();
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Throttling state is T%d (%d%% throttling applied)\n",
                state, pr->throttling.states[state].performance));
 
        return_VALUE(0);
}
 
 
static int
acpi_processor_set_throttling (
        struct acpi_processor   *pr,
        int                     state)
{
        u32                     value = 0;
        u32                     duty_mask = 0;
        u32                     duty_value = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_set_throttling");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        if ((state < 0) || (state > (pr->throttling.state_count - 1)))
                return_VALUE(-EINVAL);
 
        if (!pr->flags.throttling)
                return_VALUE(-ENODEV);
 
        if (state == pr->throttling.state)
                return_VALUE(0);
 
        __cli();
 
        /*
         * Calculate the duty_value and duty_mask.
         */
        if (state) {
                duty_value = pr->throttling.state_count - state;
 
                duty_value <<= pr->throttling.duty_offset;
 
                /* Used to clear all duty_value bits */
                duty_mask = pr->throttling.state_count - 1;
 
                duty_mask <<= acpi_fadt.duty_offset;
                duty_mask = ~duty_mask;
        }
 
        /*
         * Disable throttling by writing a 0 to bit 4.  Note that we must
         * turn it off before you can change the duty_value.
         */
        value = inl(pr->throttling.address);
        if (value & 0x10) {
                value &= 0xFFFFFFEF;
                outl(value, pr->throttling.address);
        }
 
        /*
         * Write the new duty_value and then enable throttling.  Note
         * that a state value of 0 leaves throttling disabled.
         */
        if (state) {
                value &= duty_mask;
                value |= duty_value;
                outl(value, pr->throttling.address);
 
                value |= 0x00000010;
                outl(value, pr->throttling.address);
        }
 
        pr->throttling.state = state;
 
        __sti();
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "Throttling state set to T%d (%d%%)\n", state,
                (pr->throttling.states[state].performance?pr->throttling.states[state].performance/10:0)));
 
        return_VALUE(0);
}
 
 
static int
acpi_processor_get_throttling_info (
        struct acpi_processor   *pr)
{
        int                     result = 0;
        int                     step = 0;
        int                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_throttling_info");
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
                pr->throttling.address,
                pr->throttling.duty_offset,
                pr->throttling.duty_width));
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        /* TBD: Support ACPI 2.0 objects */
 
        if (!pr->throttling.address) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
                return_VALUE(0);
        }
        else if (!pr->throttling.duty_width) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling states\n"));
                return_VALUE(0);
        }
        /* TBD: Support duty_cycle values that span bit 4. */
        else if ((pr->throttling.duty_offset
                + pr->throttling.duty_width) > 4) {
                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "duty_cycle spans bit 4\n"));
                return_VALUE(0);
        }
 
        /*
         * PIIX4 Errata: We don't support throttling on the original PIIX4.
         * This shouldn't be an issue as few (if any) mobile systems ever
         * used this part.
         */
        if (errata.piix4.throttle) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Throttling not supported on PIIX4 A- or B-step\n"));
                return_VALUE(0);
        }
 
        pr->throttling.state_count = 1 << acpi_fadt.duty_width;
 
        /*
         * Compute state values. Note that throttling displays a linear power/
         * performance relationship (at 50% performance the CPU will consume
         * 50% power).  Values are in 1/10th of a percent to preserve accuracy.
         */
 
        step = (1000 / pr->throttling.state_count);
 
        for (i=0; i<pr->throttling.state_count; i++) {
                pr->throttling.states[i].performance = step * i;
                pr->throttling.states[i].power = step * i;
        }
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d throttling states\n",
                pr->throttling.state_count));
 
        pr->flags.throttling = 1;
 
        /*
         * Disable throttling (if enabled).  We'll let subsequent policy (e.g.
         * thermal) decide to lower performance if it so chooses, but for now
         * we'll crank up the speed.
         */
 
        result = acpi_processor_get_throttling(pr);
        if (result)
                goto end;
 
        if (pr->throttling.state) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Disabling throttling (was T%d)\n",
                        pr->throttling.state));
                result = acpi_processor_set_throttling(pr, 0);
                if (result)
                        goto end;
        }
 
end:
        if (result)
                pr->flags.throttling = 0;
 
        return_VALUE(result);
}
 
 
/* --------------------------------------------------------------------------
                                 Limit Interface
   -------------------------------------------------------------------------- */
 
static int
acpi_processor_apply_limit (
        struct acpi_processor*  pr)
{
        int                     result = 0;
        u16                     px = 0;
        u16                     tx = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_apply_limit");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        if (!pr->flags.limit)
                return_VALUE(-ENODEV);
 
        if (pr->flags.performance) {
                px = pr->performance.platform_limit;
                if (pr->limit.user.px > px)
                        px = pr->limit.user.px;
                if (pr->limit.thermal.px > px)
                        px = pr->limit.thermal.px;
 
                result = acpi_processor_set_performance(pr, px);
                if (result)
                        goto end;
        }
 
        if (pr->flags.throttling) {
                if (pr->limit.user.tx > tx)
                        tx = pr->limit.user.tx;
                if (pr->limit.thermal.tx > tx)
                        tx = pr->limit.thermal.tx;
 
                result = acpi_processor_set_throttling(pr, tx);
                if (result)
                        goto end;
        }
 
        pr->limit.state.px = px;
        pr->limit.state.tx = tx;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d] limit set to (P%d:T%d)\n",
                pr->id,
                pr->limit.state.px,
                pr->limit.state.tx));
 
end:
        if (result)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Unable to set limit\n"));
 
        return_VALUE(result);
}
 
 
int
acpi_processor_set_thermal_limit (
        acpi_handle             handle,
        int                     type)
{
        int                     result = 0;
        struct acpi_processor   *pr = NULL;
        struct acpi_device      *device = NULL;
        int                     px = 0;
        int                     tx = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_set_thermal_limit");
 
        if ((type < ACPI_PROCESSOR_LIMIT_NONE)
                || (type > ACPI_PROCESSOR_LIMIT_DECREMENT))
                return_VALUE(-EINVAL);
 
        result = acpi_bus_get_device(handle, &device);
        if (result)
                return_VALUE(result);
 
        pr = (struct acpi_processor *) acpi_driver_data(device);
        if (!pr)
                return_VALUE(-ENODEV);
 
        if (!pr->flags.limit)
                return_VALUE(-ENODEV);
 
        /* Thermal limits are always relative to the current Px/Tx state. */
        if (pr->flags.performance)
                pr->limit.thermal.px = pr->performance.state;
        if (pr->flags.throttling)
                pr->limit.thermal.tx = pr->throttling.state;
 
        /*
         * Our default policy is to only use throttling at the lowest
         * performance state.
         */
 
        px = pr->limit.thermal.px;
        tx = pr->limit.thermal.tx;
 
        switch (type) {
 
        case ACPI_PROCESSOR_LIMIT_NONE:
                px = 0;
                tx = 0;
                break;
 
        case ACPI_PROCESSOR_LIMIT_INCREMENT:
                if (pr->flags.performance) {
                        if (px == (pr->performance.state_count - 1))
                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                        "At maximum performance state\n"));
                        else {
                                px++;
                                goto end;
                        }
                }
                if (pr->flags.throttling) {
                        if (tx == (pr->throttling.state_count - 1))
                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                        "At maximum throttling state\n"));
                        else
                                tx++;
                }
                break;
 
        case ACPI_PROCESSOR_LIMIT_DECREMENT:
                if (pr->flags.performance) {
                        if (px == pr->performance.platform_limit)
                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                        "At minimum performance state\n"));
                        else  {
                                px--;
                                goto end;
                        }
                }
                if (pr->flags.throttling) {
                        if (tx == 0)
                                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                                        "At minimum throttling state\n"));
                        else
                                tx--;
                }
                break;
        }
 
end:
        pr->limit.thermal.px = px;
        pr->limit.thermal.tx = tx;
 
        result = acpi_processor_apply_limit(pr);
        if (result)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to set thermal limit\n"));
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Thermal limit now (P%d:T%d)\n",
                pr->limit.thermal.px,
                pr->limit.thermal.tx));
 
        return_VALUE(result);
}
 
 
static int
acpi_processor_get_limit_info (
        struct acpi_processor   *pr)
{
        ACPI_FUNCTION_TRACE("acpi_processor_get_limit_info");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
        if (pr->flags.performance || pr->flags.throttling)
                pr->flags.limit = 1;
 
        return_VALUE(0);
}
 
 
/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */
 
struct proc_dir_entry           *acpi_processor_dir = NULL;
 
static int
acpi_processor_read_info (
        char                    *page,
        char                    **start,
        off_t                   off,
        int                     count,
        int                     *eof,
        void                    *data)
{
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    *p = page;
        int                     len = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_read_info");
 
        if (!pr || (off != 0))
                goto end;
 
        p += sprintf(p, "processor id:            %d\n",
                pr->id);
 
        p += sprintf(p, "acpi id:                 %d\n",
                pr->acpi_id);
 
        p += sprintf(p, "bus mastering control:   %s\n",
                pr->flags.bm_control ? "yes" : "no");
 
        p += sprintf(p, "power management:        %s\n",
                pr->flags.power ? "yes" : "no");
 
        p += sprintf(p, "throttling control:      %s\n",
                pr->flags.throttling ? "yes" : "no");
 
        p += sprintf(p, "performance management:  %s\n",
                pr->flags.performance ? "yes" : "no");
 
        p += sprintf(p, "limit interface:         %s\n",
                pr->flags.limit ? "yes" : "no");
 
end:
        len = (p - page);
        if (len <= off+count) *eof = 1;
        *start = page + off;
        len -= off;
        if (len>count) len = count;
        if (len<0) len = 0;
 
        return_VALUE(len);
}
 
 
static int
acpi_processor_read_power (
        char                    *page,
        char                    **start,
        off_t                   off,
        int                     count,
        int                     *eof,
        void                    *data)
{
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    *p = page;
        int                     len = 0;
        int                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_read_power");
 
        if (!pr || (off != 0))
                goto end;
 
        p += sprintf(p, "active state:            C%d\n",
                pr->power.state);
 
        p += sprintf(p, "default state:           C%d\n",
                pr->power.default_state);
 
        p += sprintf(p, "bus master activity:     %08x\n",
                pr->power.bm_activity);
 
        p += sprintf(p, "states:\n");
 
        for (i=1; i<ACPI_C_STATE_COUNT; i++) {
 
                p += sprintf(p, "   %cC%d:                  ",
                        (i == pr->power.state?'*':' '), i);
 
                if (!pr->power.states[i].valid) {
                        p += sprintf(p, "<not supported>\n");
                        continue;
                }
 
                if (pr->power.states[i].promotion.state)
                        p += sprintf(p, "promotion[C%d] ",
                                pr->power.states[i].promotion.state);
                else
                        p += sprintf(p, "promotion[--] ");
 
                if (pr->power.states[i].demotion.state)
                        p += sprintf(p, "demotion[C%d] ",
                                pr->power.states[i].demotion.state);
                else
                        p += sprintf(p, "demotion[--] ");
 
                p += sprintf(p, "latency[%03d] usage[%08d]\n",
                        pr->power.states[i].latency,
                        pr->power.states[i].usage);
        }
 
end:
        len = (p - page);
        if (len <= off+count) *eof = 1;
        *start = page + off;
        len -= off;
        if (len>count) len = count;
        if (len<0) len = 0;
 
        return_VALUE(len);
}
 
 
static int
acpi_processor_read_performance (
        char                    *page,
        char                    **start,
        off_t                   off,
        int                     count,
        int                     *eof,
        void                    *data)
{
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    *p = page;
        int                     len = 0;
        int                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_read_performance");
 
        if (!pr || (off != 0))
                goto end;
 
        if (!pr->flags.performance) {
                p += sprintf(p, "<not supported>\n");
                goto end;
        }
 
        p += sprintf(p, "state count:             %d\n",
                pr->performance.state_count);
 
        p += sprintf(p, "active state:            P%d\n",
                pr->performance.state);
 
        p += sprintf(p, "states:\n");
 
        for (i=0; i<pr->performance.state_count; i++)
                p += sprintf(p, "   %cP%d:                  %d MHz, %d mW, %d uS\n",
                        (i == pr->performance.state?'*':' '), i,
                        (u32) pr->performance.states[i].core_frequency,
                        (u32) pr->performance.states[i].power,
                        (u32) pr->performance.states[i].transition_latency);
 
end:
        len = (p - page);
        if (len <= off+count) *eof = 1;
        *start = page + off;
        len -= off;
        if (len>count) len = count;
        if (len<0) len = 0;
 
        return_VALUE(len);
}
 
 
static int
acpi_processor_write_performance (
        struct file             *file,
        const char              *buffer,
        unsigned long           count,
        void                    *data)
{
        int                     result = 0;
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    state_string[12] = {'\0'};
 
        ACPI_FUNCTION_TRACE("acpi_processor_write_performance");
 
        if (!pr || (count > sizeof(state_string) - 1))
                return_VALUE(-EINVAL);
 
        if (copy_from_user(state_string, buffer, count))
                return_VALUE(-EFAULT);
 
        state_string[count] = '\0';
 
        result = acpi_processor_set_performance(pr,
                simple_strtoul(state_string, NULL, 0));
        if (result)
                return_VALUE(result);
 
        return_VALUE(count);
}
 
 
static int
acpi_processor_read_throttling (
        char                    *page,
        char                    **start,
        off_t                   off,
        int                     count,
        int                     *eof,
        void                    *data)
{
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    *p = page;
        int                     len = 0;
        int                     i = 0;
        int                     result = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_read_throttling");
 
        if (!pr || (off != 0))
                goto end;
 
        if (!(pr->throttling.state_count > 0)) {
                p += sprintf(p, "<not supported>\n");
                goto end;
        }
 
        result = acpi_processor_get_throttling(pr);
 
        if (result) {
                p += sprintf(p, "Could not determine current throttling state.\n");
                goto end;
        }
 
        p += sprintf(p, "state count:             %d\n",
                pr->throttling.state_count);
 
        p += sprintf(p, "active state:            T%d\n",
                pr->throttling.state);
 
        p += sprintf(p, "states:\n");
 
        for (i=0; i<pr->throttling.state_count; i++)
                p += sprintf(p, "   %cT%d:                  %02d%%\n",
                        (i == pr->throttling.state?'*':' '), i,
                        (pr->throttling.states[i].performance?pr->throttling.states[i].performance/10:0));
 
end:
        len = (p - page);
        if (len <= off+count) *eof = 1;
        *start = page + off;
        len -= off;
        if (len>count) len = count;
        if (len<0) len = 0;
 
        return_VALUE(len);
}
 
 
static int
acpi_processor_write_throttling (
        struct file             *file,
        const char              *buffer,
        unsigned long           count,
        void                    *data)
{
        int                     result = 0;
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    state_string[12] = {'\0'};
 
        ACPI_FUNCTION_TRACE("acpi_processor_write_throttling");
 
        if (!pr || (count > sizeof(state_string) - 1))
                return_VALUE(-EINVAL);
 
        if (copy_from_user(state_string, buffer, count))
                return_VALUE(-EFAULT);
 
        state_string[count] = '\0';
 
        result = acpi_processor_set_throttling(pr,
                simple_strtoul(state_string, NULL, 0));
        if (result)
                return_VALUE(result);
 
        return_VALUE(count);
}
 
 
static int
acpi_processor_read_limit (
        char                    *page,
        char                    **start,
        off_t                   off,
        int                     count,
        int                     *eof,
        void                    *data)
{
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    *p = page;
        int                     len = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_read_limit");
 
        if (!pr || (off != 0))
                goto end;
 
        if (!pr->flags.limit) {
                p += sprintf(p, "<not supported>\n");
                goto end;
        }
 
        p += sprintf(p, "active limit:            P%d:T%d\n",
                pr->limit.state.px, pr->limit.state.tx);
 
        p += sprintf(p, "platform limit:          P%d:T0\n",
                pr->flags.performance?pr->performance.platform_limit:0);
 
        p += sprintf(p, "user limit:              P%d:T%d\n",
                pr->limit.user.px, pr->limit.user.tx);
 
        p += sprintf(p, "thermal limit:           P%d:T%d\n",
                pr->limit.thermal.px, pr->limit.thermal.tx);
 
end:
        len = (p - page);
        if (len <= off+count) *eof = 1;
        *start = page + off;
        len -= off;
        if (len>count) len = count;
        if (len<0) len = 0;
 
        return_VALUE(len);
}
 
 
static int
acpi_processor_write_limit (
        struct file             *file,
        const char              *buffer,
        unsigned long           count,
        void                    *data)
{
        int                     result = 0;
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        char                    limit_string[25] = {'\0'};
        int                     px = 0;
        int                     tx = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_write_limit");
 
        if (!pr || (count > sizeof(limit_string) - 1)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid argument\n"));
                return_VALUE(-EINVAL);
        }
 
        if (copy_from_user(limit_string, buffer, count)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid data\n"));
                return_VALUE(-EFAULT);
        }
 
        limit_string[count] = '\0';
 
        if (sscanf(limit_string, "%d:%d", &px, &tx) != 2) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid data format\n"));
                return_VALUE(-EINVAL);
        }
 
        if (pr->flags.performance) {
                if ((px < pr->performance.platform_limit)
                        || (px > (pr->performance.state_count - 1))) {
                        ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid px\n"));
                        return_VALUE(-EINVAL);
                }
                pr->limit.user.px = px;
        }
 
        if (pr->flags.throttling) {
                if ((tx < 0) || (tx > (pr->throttling.state_count - 1))) {
                        ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid tx\n"));
                        return_VALUE(-EINVAL);
                }
                pr->limit.user.tx = tx;
        }
 
        result = acpi_processor_apply_limit(pr);
 
        return_VALUE(count);
}
 
 
static int
acpi_processor_add_fs (
        struct acpi_device      *device)
{
        struct proc_dir_entry   *entry = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_add_fs");
 
        if (!acpi_device_dir(device)) {
                acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
                        acpi_processor_dir);
                if (!acpi_device_dir(device))
                        return_VALUE(-ENODEV);
        }
 
        /* 'info' [R] */
        entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
                S_IRUGO, acpi_device_dir(device));
        if (!entry)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to create '%s' fs entry\n",
                        ACPI_PROCESSOR_FILE_INFO));
        else {
                entry->read_proc = acpi_processor_read_info;
                entry->data = acpi_driver_data(device);
        }
 
        /* 'power' [R] */
        entry = create_proc_entry(ACPI_PROCESSOR_FILE_POWER,
                S_IRUGO, acpi_device_dir(device));
        if (!entry)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to create '%s' fs entry\n",
                        ACPI_PROCESSOR_FILE_POWER));
        else {
                entry->read_proc = acpi_processor_read_power;
                entry->data = acpi_driver_data(device);
        }
 
        /* 'performance' [R/W] */
        entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
                S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
        if (!entry)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to create '%s' fs entry\n",
                        ACPI_PROCESSOR_FILE_PERFORMANCE));
        else {
                entry->read_proc = acpi_processor_read_performance;
                entry->write_proc = acpi_processor_write_performance;
                entry->data = acpi_driver_data(device);
        }
 
        /* 'throttling' [R/W] */
        entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
                S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
        if (!entry)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to create '%s' fs entry\n",
                        ACPI_PROCESSOR_FILE_THROTTLING));
        else {
                entry->read_proc = acpi_processor_read_throttling;
                entry->write_proc = acpi_processor_write_throttling;
                entry->data = acpi_driver_data(device);
        }
 
        /* 'limit' [R/W] */
        entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
                S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
        if (!entry)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Unable to create '%s' fs entry\n",
                        ACPI_PROCESSOR_FILE_LIMIT));
        else {
                entry->read_proc = acpi_processor_read_limit;
                entry->write_proc = acpi_processor_write_limit;
                entry->data = acpi_driver_data(device);
        }
 
        return_VALUE(0);
}
 
 
static int
acpi_processor_remove_fs (
        struct acpi_device      *device)
{
        ACPI_FUNCTION_TRACE("acpi_processor_remove_fs");
 
        if (acpi_device_dir(device)) {
                remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
                acpi_device_dir(device) = NULL;
        }
 
        return_VALUE(0);
}
 
 
/* --------------------------------------------------------------------------
                                 Driver Interface
   -------------------------------------------------------------------------- */
 
static int
acpi_processor_get_info (
        struct acpi_processor   *pr)
{
        acpi_status             status = 0;
        union acpi_object       object = {0};
        struct acpi_buffer      buffer = {sizeof(union acpi_object), &object};
        static int              cpu_index = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_get_info");
 
        if (!pr)
                return_VALUE(-EINVAL);
 
#ifdef CONFIG_SMP
        if (smp_num_cpus > 1)
                errata.smp = smp_num_cpus;
 
        /*
         *  Extra Processor objects may be enumerated on MP systems with
         *  less than the max # of CPUs. They should be ignored.
         */
        if ((cpu_index + 1) > smp_num_cpus)
                return_VALUE(-ENODEV);
#endif
 
        acpi_processor_errata(pr);
 
        /*
         * Check to see if we have bus mastering arbitration control.  This
         * is required for proper C3 usage (to maintain cache coherency).
         */
        if (acpi_fadt.V1_pm2_cnt_blk && acpi_fadt.pm2_cnt_len) {
                pr->flags.bm_control = 1;
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Bus mastering arbitration control present\n"));
        }
        else
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "No bus mastering arbitration control\n"));
 
        /*
         * Evalute the processor object.  Note that it is common on SMP to
         * have the first (boot) processor with a valid PBLK address while
         * all others have a NULL address.
         */
        status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Error evaluating processor object\n"));
                return_VALUE(-ENODEV);
        }
 
        /*
         * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
         *      >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
         */
        pr->id = cpu_index++;
        pr->acpi_id = object.processor.proc_id;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
                pr->acpi_id));
 
        if (!object.processor.pblk_address)
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
        else if (object.processor.pblk_length != 6)
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid PBLK length [%d]\n",
                        object.processor.pblk_length));
        else {
                pr->throttling.address = object.processor.pblk_address;
                pr->throttling.duty_offset = acpi_fadt.duty_offset;
                pr->throttling.duty_width = acpi_fadt.duty_width;
                pr->power.states[ACPI_STATE_C2].address =
                        object.processor.pblk_address + 4;
                pr->power.states[ACPI_STATE_C3].address =
                        object.processor.pblk_address + 5;
        }
 
        acpi_processor_get_power_info(pr);
        acpi_processor_get_performance_info(pr);
        acpi_processor_get_throttling_info(pr);
        acpi_processor_get_limit_info(pr);
 
        return_VALUE(0);
}
 
 
static void
acpi_processor_notify (
        acpi_handle             handle,
        u32                     event,
        void                    *data)
{
        int                     result = 0;
        struct acpi_processor   *pr = (struct acpi_processor *) data;
        struct acpi_device      *device = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_notify");
 
        if (!pr)
                return_VOID;
 
        if (acpi_bus_get_device(pr->handle, &device))
                return_VOID;
 
        switch (event) {
        case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
                result = acpi_processor_get_platform_limit(pr);
                if (!result)
                        acpi_processor_apply_limit(pr);
 
                acpi_bus_generate_event(device, event,
                        pr->performance.platform_limit);
                break;
        case ACPI_PROCESSOR_NOTIFY_POWER:
                /* TBD */
                acpi_bus_generate_event(device, event, 0);
                break;
        default:
                ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                        "Unsupported event [0x%x]\n", event));
                break;
        }
 
        return_VOID;
}
 
 
static int
acpi_processor_add (
        struct acpi_device      *device)
{
        int                     result = 0;
        acpi_status             status = AE_OK;
        struct acpi_processor   *pr = NULL;
        u32                     i = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_add");
 
        if (!device)
                return_VALUE(-EINVAL);
 
        pr = kmalloc(sizeof(struct acpi_processor), GFP_KERNEL);
        if (!pr)
                return_VALUE(-ENOMEM);
        memset(pr, 0, sizeof(struct acpi_processor));
 
        pr->handle = device->handle;
        sprintf(acpi_device_name(device), "%s", ACPI_PROCESSOR_DEVICE_NAME);
        sprintf(acpi_device_class(device), "%s", ACPI_PROCESSOR_CLASS);
        acpi_driver_data(device) = pr;
 
        result = acpi_processor_get_info(pr);
        if (result)
                goto end;
 
        result = acpi_processor_add_fs(device);
        if (result)
                goto end;
 
        status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
                acpi_processor_notify, pr);
        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Error installing notify handler\n"));
                result = -ENODEV;
                goto end;
        }
 
        processors[pr->id] = pr;
 
        /*
         * Install the idle handler if processor power management is supported.
         * Note that the default idle handler (default_idle) will be used on
         * platforms that only support C1.
         */
        if ((pr->id == 0) && (pr->flags.power)) {
                pm_idle_save = pm_idle;
                pm_idle = acpi_processor_idle;
        }
 
        printk(KERN_INFO PREFIX "%s [%s] (supports",
                acpi_device_name(device), acpi_device_bid(device));
        for (i=1; i<ACPI_C_STATE_COUNT; i++)
                if (pr->power.states[i].valid)
                        printk(" C%d", i);
        if (pr->flags.performance)
                printk(", %d performance states", pr->performance.state_count);
        if (pr->flags.throttling)
                printk(", %d throttling states", pr->throttling.state_count);
        printk(")\n");
 
end:
        if (result) {
                acpi_processor_remove_fs(device);
                kfree(pr);
        }
 
        return_VALUE(result);
}
 
 
static int
acpi_processor_remove (
        struct acpi_device      *device,
        int                     type)
{
        acpi_status             status = AE_OK;
        struct acpi_processor   *pr = NULL;
 
        ACPI_FUNCTION_TRACE("acpi_processor_remove");
 
        if (!device || !acpi_driver_data(device))
                return_VALUE(-EINVAL);
 
        pr = (struct acpi_processor *) acpi_driver_data(device);
 
        /* Unregister the idle handler when processor #0 is removed. */
        if (pr->id == 0)
                pm_idle = pm_idle_save;
 
        status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
                acpi_processor_notify);
        if (ACPI_FAILURE(status)) {
                ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
                        "Error removing notify handler\n"));
        }
 
        acpi_processor_remove_fs(device);
 
        processors[pr->id] = NULL;
 
        kfree(pr);
 
        return_VALUE(0);
}
 
 
static int __init
acpi_processor_init (void)
{
        int                     result = 0;
 
        ACPI_FUNCTION_TRACE("acpi_processor_init");
 
        memset(&processors, 0, sizeof(processors));
        memset(&errata, 0, sizeof(errata));
 
        acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
        if (!acpi_processor_dir)
                return_VALUE(-ENODEV);
 
        result = acpi_bus_register_driver(&acpi_processor_driver);
        if (result < 0) {
                remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
                return_VALUE(-ENODEV);
        }
 
        return_VALUE(0);
}
 
 
static void __exit
acpi_processor_exit (void)
{
        ACPI_FUNCTION_TRACE("acpi_processor_exit");
 
        acpi_bus_unregister_driver(&acpi_processor_driver);
 
        remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
 
        return_VOID;
}
 
 
module_init(acpi_processor_init);
module_exit(acpi_processor_exit);
 
EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [acpi/] [processor.c] - Blame information for rev 1774

Line No.	Rev	Author	Line
1	1275	phoenix	`/*`
2			`* acpi_processor.c - ACPI Processor Driver ($Revision: 1.1.1.1 $)`
3			`*`
4			`* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>`
5			`* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>`
6			`*`
7			`* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`
8			`*`
9			`* This program is free software; you can redistribute it and/or modify`
10			`* it under the terms of the GNU General Public License as published by`
11			`* the Free Software Foundation; either version 2 of the License, or (at`
12			`* your option) any later version.`
13			`*`
14			`* This program is distributed in the hope that it will be useful, but`
15			`* WITHOUT ANY WARRANTY; without even the implied warranty of`
16			`* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU`
17			`* General Public License for more details.`
18			`*`
19			`* You should have received a copy of the GNU General Public License along`
20			`* with this program; if not, write to the Free Software Foundation, Inc.,`
21			`* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.`
22			`*`
23			`* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~`
24			`* TBD:`
25			`* 1. Make # power/performance states dynamic.`
26			`* 2. Support duty_cycle values that span bit 4.`
27			`* 3. Optimize by having scheduler determine business instead of`
28			`* having us try to calculate it here.`
29			`* 4. Need C1 timing -- must modify kernel (IRQ handler) to get this.`
30			`*/`
31
32			`#include <linux/kernel.h>`
33			`#include <linux/module.h>`
34			`#include <linux/init.h>`
35			`#include <linux/types.h>`
36			`#include <linux/pci.h>`
37			`#include <linux/pm.h>`
38			`#include <asm/io.h>`
39			`#include <asm/system.h>`
40			`#include <asm/delay.h>`