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@fluxnic.net>
  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 <mach/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(long);
  36
  37 #define SAVE(x)         sleep_save[SLEEP_SAVE_##x] = x
  38 #define RESTORE(x)      x = sleep_save[SLEEP_SAVE_##x]
  39
  40 /*
  41  * List of global SA11x0 peripheral registers to preserve.
  42  * More ones like CP and general purpose register values are preserved
  43  * on the stack and then the stack pointer is stored last in sleep.S.
  44  */
  45 enum {  SLEEP_SAVE_GPDR, SLEEP_SAVE_GAFR,
  46         SLEEP_SAVE_PPDR, SLEEP_SAVE_PPSR, SLEEP_SAVE_PPAR, SLEEP_SAVE_PSDR,
  47
  48         SLEEP_SAVE_Ser1SDCR0,
  49
  50         SLEEP_SAVE_COUNT
  51 };
  52
  53
  54 static int sa11x0_pm_enter(suspend_state_t state)
  55 {
  56         unsigned long gpio, sleep_save[SLEEP_SAVE_COUNT];
  57
  58         gpio = GPLR;
  59
  60         /* save vital registers */
  61         SAVE(GPDR);
  62         SAVE(GAFR);
  63
  64         SAVE(PPDR);
  65         SAVE(PPSR);
  66         SAVE(PPAR);
  67         SAVE(PSDR);
  68
  69         SAVE(Ser1SDCR0);
  70
  71         /* Clear previous reset status */
  72         RCSR = RCSR_HWR | RCSR_SWR | RCSR_WDR | RCSR_SMR;
  73
  74         /* set resume return address */
  75         PSPR = virt_to_phys(cpu_resume);
  76
  77         /* go zzz */
  78         sa1100_cpu_suspend(PLAT_PHYS_OFFSET - PAGE_OFFSET);
  79
  80         cpu_init();
  81
  82         /*
  83          * Ensure not to come back here if it wasn't intended
  84          */
  85         PSPR = 0;
  86
  87         /*
  88          * Ensure interrupt sources are disabled; we will re-init
  89          * the interrupt subsystem via the device manager.
  90          */
  91         ICLR = 0;
  92         ICCR = 1;
  93         ICMR = 0;
  94
  95         /* restore registers */
  96         RESTORE(GPDR);
  97         RESTORE(GAFR);
  98
  99         RESTORE(PPDR);
 100         RESTORE(PPSR);
 101         RESTORE(PPAR);
 102         RESTORE(PSDR);
 103
 104         RESTORE(Ser1SDCR0);
 105
 106         GPSR = gpio;
 107         GPCR = ~gpio;
 108
 109         /*
 110          * Clear the peripheral sleep-hold bit.
 111          */
 112         PSSR = PSSR_PH;
 113
 114         return 0;
 115 }
 116
 117 static const struct platform_suspend_ops sa11x0_pm_ops = {
 118         .enter          = sa11x0_pm_enter,
 119         .valid          = suspend_valid_only_mem,
 120 };
 121
 122 static int __init sa11x0_pm_init(void)
 123 {
 124         suspend_set_ops(&sa11x0_pm_ops);
 125         return 0;
 126 }
 127
 128 late_initcall(sa11x0_pm_init);