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         /*
  92          * Ensure not to come back here if it wasn't intended
  93          */
  94         PSPR = 0;
  95
  96         /*
  97          * Ensure interrupt sources are disabled; we will re-init
  98          * the interrupt subsystem via the device manager.
  99          */
 100         ICLR = 0;
 101         ICCR = 1;
 102         ICMR = 0;
 103
 104         /* restore registers */
 105         RESTORE(GPDR);
 106         RESTORE(GAFR);
 107
 108         RESTORE(PPDR);
 109         RESTORE(PPSR);
 110         RESTORE(PPAR);
 111         RESTORE(PSDR);
 112
 113         RESTORE(Ser1SDCR0);
 114
 115         GPSR = gpio;
 116         GPCR = ~gpio;
 117
 118         /*
 119          * Clear the peripheral sleep-hold bit.
 120          */
 121         PSSR = PSSR_PH;
 122
 123         /* restore current time */
 124         rtc.tv_sec = RCNR;
 125         restore_time_delta(&delta, &rtc);
 126
 127         return 0;
 128 }
 129
 130 unsigned long sleep_phys_sp(void *sp)
 131 {
 132         return virt_to_phys(sp);
 133 }
 134
 135 /*
 136  * Called after processes are frozen, but before we shut down devices.
 137  */
 138 static int sa11x0_pm_prepare(suspend_state_t state)
 139 {
 140         return 0;
 141 }
 142
 143 /*
 144  * Called after devices are re-setup, but before processes are thawed.
 145  */
 146 static int sa11x0_pm_finish(suspend_state_t state)
 147 {
 148         return 0;
 149 }
 150
 151 /*
 152  * Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
 153  */
 154 static struct pm_ops sa11x0_pm_ops = {
 155         .pm_disk_mode   = PM_DISK_FIRMWARE,
 156         .prepare        = sa11x0_pm_prepare,
 157         .enter          = sa11x0_pm_enter,
 158         .finish         = sa11x0_pm_finish,
 159 };
 160
 161 static int __init sa11x0_pm_init(void)
 162 {
 163         pm_set_ops(&sa11x0_pm_ops);
 164         return 0;
 165 }
 166
 167 late_initcall(sa11x0_pm_init);