arch/arm/mach-sa1100/pm.c

   1 /*
   2  * SA1100 Power Management Routines
   3  *
   4  * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License.
   8  *
   9  * History:
  10  *
  11  * 2001-02-06:  Cliff Brake         Initial code
  12  *
  13  * 2001-02-25:  Sukjae Cho <sjcho@east.isi.edu> &
  14  *              Chester Kuo <chester@linux.org.tw>
  15  *                      Save more value for the resume function! Support
  16  *                      Bitsy/Assabet/Freebird board
  17  *
  18  * 2001-08-29:  Nicolas Pitre <nico@cam.org>
  19  *                      Cleaned up, pushed platform dependent stuff
  20  *                      in the platform specific files.
  21  *
  22  * 2002-05-27:  Nicolas Pitre   Killed sleep.h and the kmalloced save array.
  23  *                              Storage is local on the stack now.
  24  */
  25 #include <linux/init.h>
  26 #include <linux/suspend.h>
  27 #include <linux/errno.h>
  28 #include <linux/time.h>
  29
  30 #include <asm/hardware.h>
  31 #include <asm/memory.h>
  32 #include <asm/system.h>
  33 #include <asm/mach/time.h>
  34
  35 extern void sa1100_cpu_suspend(void);
  36 extern void sa1100_cpu_resume(void);
  37
  38 #define SAVE(x)         sleep_save[SLEEP_SAVE_##x] = x
  39 #define RESTORE(x)      x = sleep_save[SLEEP_SAVE_##x]
  40
  41 /*
  42  * List of global SA11x0 peripheral registers to preserve.
  43  * More ones like CP and general purpose register values are preserved
  44  * on the stack and then the stack pointer is stored last in sleep.S.
  45  */
  46 enum {  SLEEP_SAVE_SP = 0,
  47
  48         SLEEP_SAVE_GPDR, SLEEP_SAVE_GAFR,
  49         SLEEP_SAVE_PPDR, SLEEP_SAVE_PPSR, SLEEP_SAVE_PPAR, SLEEP_SAVE_PSDR,
  50
  51         SLEEP_SAVE_Ser1SDCR0,
  52
  53         SLEEP_SAVE_SIZE
  54 };
  55
  56
  57 static int sa11x0_pm_enter(suspend_state_t state)
  58 {
  59         unsigned long gpio, sleep_save[SLEEP_SAVE_SIZE];
  60         struct timespec delta, rtc;
  61
  62         if (state != PM_SUSPEND_MEM)
  63                 return -EINVAL;
  64
  65         /* preserve current time */
  66         rtc.tv_sec = RCNR;
  67         rtc.tv_nsec = 0;
  68         save_time_delta(&delta, &rtc);
  69         gpio = GPLR;
  70
  71         /* save vital registers */
  72         SAVE(GPDR);
  73         SAVE(GAFR);
  74
  75         SAVE(PPDR);
  76         SAVE(PPSR);
  77         SAVE(PPAR);
  78         SAVE(PSDR);
  79
  80         SAVE(Ser1SDCR0);
  81
  82         /* Clear previous reset status */
  83         RCSR = RCSR_HWR | RCSR_SWR | RCSR_WDR | RCSR_SMR;
  84
  85         /* set resume return address */
  86         PSPR = virt_to_phys(sa1100_cpu_resume);
  87
  88         /* go zzz */
  89         sa1100_cpu_suspend();
  90
  91         cpu_init();
  92
  93         /*
  94          * Ensure not to come back here if it wasn't intended
  95          */
  96         PSPR = 0;
  97
  98         /*
  99          * Ensure interrupt sources are disabled; we will re-init
 100          * the interrupt subsystem via the device manager.
 101          */
 102         ICLR = 0;
 103         ICCR = 1;
 104         ICMR = 0;
 105
 106         /* restore registers */
 107         RESTORE(GPDR);
 108         RESTORE(GAFR);
 109
 110         RESTORE(PPDR);
 111         RESTORE(PPSR);
 112         RESTORE(PPAR);
 113         RESTORE(PSDR);
 114
 115         RESTORE(Ser1SDCR0);
 116
 117         GPSR = gpio;
 118         GPCR = ~gpio;
 119
 120         /*
 121          * Clear the peripheral sleep-hold bit.
 122          */
 123         PSSR = PSSR_PH;
 124
 125         /* restore current time */
 126         rtc.tv_sec = RCNR;
 127         restore_time_delta(&delta, &rtc);
 128
 129         return 0;
 130 }
 131
 132 unsigned long sleep_phys_sp(void *sp)
 133 {
 134         return virt_to_phys(sp);
 135 }
 136
 137 /*
 138  * Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
 139  */
 140 static struct pm_ops sa11x0_pm_ops = {
 141         .pm_disk_mode   = PM_DISK_FIRMWARE,
 142         .enter          = sa11x0_pm_enter,
 143 };
 144
 145 static int __init sa11x0_pm_init(void)
 146 {
 147         pm_set_ops(&sa11x0_pm_ops);
 148         return 0;
 149 }
 150
 151 late_initcall(sa11x0_pm_init);