pm.c

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/*
 * SA1100 Power Management Routines
 *
 * Copyright (c) 2001 Cliff Brake <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License.
 *
 * History:
 *
 * 2001-02-06:  Cliff Brake         Initial code
 *
 * 2001-02-25:  Sukjae Cho <[email protected]> &
 *      Chester Kuo <[email protected]>
 *          Save more value for the resume function! Support
 *          Bitsy/Assabet/Freebird board
 *
 * 2001-08-29:  Nicolas Pitre <[email protected]>
 *          Cleaned up, pushed platform dependent stuff
 *          in the platform specific files.
 *
 * 2002-05-27:  Nicolas Pitre   Killed sleep.h and the kmalloced save array.
 *              Storage is local on the stack now.
 */
#include <linux/init.h>
#include <linux/io.h>
#include <linux/suspend.h>
#include <linux/errno.h>
#include <linux/time.h>

#include <mach/hardware.h>
#include <asm/memory.h>
#include <asm/suspend.h>
#include <asm/mach/time.h>

extern int sa1100_finish_suspend(unsigned long);

#define SAVE(x)     sleep_save[SLEEP_SAVE_##x] = x
#define RESTORE(x)  x = sleep_save[SLEEP_SAVE_##x]

/*
 * List of global SA11x0 peripheral registers to preserve.
 * More ones like CP and general purpose register values are preserved
 * on the stack and then the stack pointer is stored last in sleep.S.
 */
enum {  SLEEP_SAVE_GPDR, SLEEP_SAVE_GAFR,
    SLEEP_SAVE_PPDR, SLEEP_SAVE_PPSR, SLEEP_SAVE_PPAR, SLEEP_SAVE_PSDR,

    SLEEP_SAVE_Ser1SDCR0,

    SLEEP_SAVE_COUNT
};


static int sa11x0_pm_enter(suspend_state_t state)
{
    unsigned long gpio, sleep_save[SLEEP_SAVE_COUNT];

    gpio = GPLR;

    /* save vital registers */
    SAVE(GPDR);
    SAVE(GAFR);

    SAVE(PPDR);
    SAVE(PPSR);
    SAVE(PPAR);
    SAVE(PSDR);

    SAVE(Ser1SDCR0);

    /* Clear previous reset status */
    RCSR = RCSR_HWR | RCSR_SWR | RCSR_WDR | RCSR_SMR;

    /* set resume return address */
    PSPR = virt_to_phys(cpu_resume);

    /* go zzz */
    cpu_suspend(0, sa1100_finish_suspend);

    /*
     * Ensure not to come back here if it wasn't intended
     */
    PSPR = 0;

    /*
     * Ensure interrupt sources are disabled; we will re-init
     * the interrupt subsystem via the device manager.
     */
    ICLR = 0;
    ICCR = 1;
    ICMR = 0;

    /* restore registers */
    RESTORE(GPDR);
    RESTORE(GAFR);

    RESTORE(PPDR);
    RESTORE(PPSR);
    RESTORE(PPAR);
    RESTORE(PSDR);

    RESTORE(Ser1SDCR0);

    GPSR = gpio;
    GPCR = ~gpio;

    /*
     * Clear the peripheral sleep-hold bit.
     */
    PSSR = PSSR_PH;

    return 0;
}

static const struct platform_suspend_ops sa11x0_pm_ops = {
    .enter      = sa11x0_pm_enter,
    .valid      = suspend_valid_only_mem,
};

int __init sa11x0_pm_init(void)
{
    suspend_set_ops(&sa11x0_pm_ops);
    return 0;
}