root/arch/arm/mach-s3c24xx/sleep-s3c2410.S

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (c) 2004 Simtec Electronics
   4  *      Ben Dooks <ben@simtec.co.uk>
   5  *
   6  * S3C2410 Power Manager (Suspend-To-RAM) support
   7  *
   8  * Based on PXA/SA1100 sleep code by:
   9  *      Nicolas Pitre, (c) 2002 Monta Vista Software Inc
  10  *      Cliff Brake, (c) 2001
  11  */
  12 
  13 #include <linux/linkage.h>
  14 #include <linux/serial_s3c.h>
  15 #include <asm/assembler.h>
  16 #include <mach/hardware.h>
  17 #include <mach/map.h>
  18 
  19 #include <mach/regs-gpio.h>
  20 #include <mach/regs-clock.h>
  21 
  22 #include "regs-mem.h"
  23 
  24         /* s3c2410_cpu_suspend
  25          *
  26          * put the cpu into sleep mode
  27         */
  28 
  29 ENTRY(s3c2410_cpu_suspend)
  30         @@ prepare cpu to sleep
  31 
  32         ldr     r4, =S3C2410_REFRESH
  33         ldr     r5, =S3C24XX_MISCCR
  34         ldr     r6, =S3C2410_CLKCON
  35         ldr     r7, [r4]                @ get REFRESH (and ensure in TLB)
  36         ldr     r8, [r5]                @ get MISCCR (and ensure in TLB)
  37         ldr     r9, [r6]                @ get CLKCON (and ensure in TLB)
  38 
  39         orr     r7, r7, #S3C2410_REFRESH_SELF   @ SDRAM sleep command
  40         orr     r8, r8, #S3C2410_MISCCR_SDSLEEP @ SDRAM power-down signals
  41         orr     r9, r9, #S3C2410_CLKCON_POWER   @ power down command
  42 
  43         teq     pc, #0                  @ first as a trial-run to load cache
  44         bl      s3c2410_do_sleep
  45         teq     r0, r0                  @ now do it for real
  46         b       s3c2410_do_sleep        @
  47 
  48         @@ align next bit of code to cache line
  49         .align  5
  50 s3c2410_do_sleep:
  51         streq   r7, [r4]                        @ SDRAM sleep command
  52         streq   r8, [r5]                        @ SDRAM power-down config
  53         streq   r9, [r6]                        @ CPU sleep
  54 1:      beq     1b
  55         ret     lr