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/suspend.h>
  33 #include <asm/system.h>
  34 #include <asm/mach/time.h>
  35
  36 extern int sa1100_finish_suspend(unsigned long);
  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_GPDR, SLEEP_SAVE_GAFR,
  47         SLEEP_SAVE_PPDR, SLEEP_SAVE_PPSR, SLEEP_SAVE_PPAR, SLEEP_SAVE_PSDR,
  48
  49         SLEEP_SAVE_Ser1SDCR0,
  50
  51         SLEEP_SAVE_COUNT
  52 };
  53
  54
  55 static int sa11x0_pm_enter(suspend_state_t state)
  56 {
  57         unsigned long gpio, sleep_save[SLEEP_SAVE_COUNT];
  58
  59         gpio = GPLR;
  60
  61         /* save vital registers */
  62         SAVE(GPDR);
  63         SAVE(GAFR);
  64
  65         SAVE(PPDR);
  66         SAVE(PPSR);
  67         SAVE(PPAR);
  68         SAVE(PSDR);
  69
  70         SAVE(Ser1SDCR0);
  71
  72         /* Clear previous reset status */
  73         RCSR = RCSR_HWR | RCSR_SWR | RCSR_WDR | RCSR_SMR;
  74
  75         /* set resume return address */
  76         PSPR = virt_to_phys(cpu_resume);
  77
  78         /* go zzz */
  79         cpu_suspend(0, sa1100_finish_suspend);
  80
  81         /*
  82          * Ensure not to come back here if it wasn't intended
  83          */
  84         PSPR = 0;
  85
  86         /*
  87          * Ensure interrupt sources are disabled; we will re-init
  88          * the interrupt subsystem via the device manager.
  89          */
  90         ICLR = 0;
  91         ICCR = 1;
  92         ICMR = 0;
  93
  94         /* restore registers */
  95         RESTORE(GPDR);
  96         RESTORE(GAFR);
  97
  98         RESTORE(PPDR);
  99         RESTORE(PPSR);
 100         RESTORE(PPAR);
 101         RESTORE(PSDR);
 102
 103         RESTORE(Ser1SDCR0);
 104
 105         GPSR = gpio;
 106         GPCR = ~gpio;
 107
 108         /*
 109          * Clear the peripheral sleep-hold bit.
 110          */
 111         PSSR = PSSR_PH;
 112
 113         return 0;
 114 }
 115
 116 static const struct platform_suspend_ops sa11x0_pm_ops = {
 117         .enter          = sa11x0_pm_enter,
 118         .valid          = suspend_valid_only_mem,
 119 };
 120
 121 static int __init sa11x0_pm_init(void)
 122 {
 123         suspend_set_ops(&sa11x0_pm_ops);
 124         return 0;
 125 }
 126
 127 late_initcall(sa11x0_pm_init);