root/arch/sh/boards/mach-ecovec24/sdram.S

   1 /* SPDX-License-Identifier: GPL-2.0
   2  *
   3  * Ecovec24 sdram self/auto-refresh setup code
   4  *
   5  *  Copyright (C) 2009 Magnus Damm
   6  */
   7 
   8 #include <linux/sys.h>
   9 #include <linux/errno.h>
  10 #include <linux/linkage.h>
  11 #include <asm/asm-offsets.h>
  12 #include <asm/suspend.h>
  13 #include <asm/romimage-macros.h>
  14 
  15 /* code to enter and leave self-refresh. must be self-contained.
  16  * this code will be copied to on-chip memory and executed from there.
  17  */
  18         .balign 4
  19 ENTRY(ecovec24_sdram_enter_start)
  20 
  21         /* DBSC: put memory in self-refresh mode */
  22 
  23         ED 0xFD000010, 0x00000000 /* DBEN */
  24         ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
  25         ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
  26         ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
  27         ED 0xFD000040, 0x00000001 /* DBRFPDN0 */
  28 
  29         rts
  30          nop
  31 
  32 ENTRY(ecovec24_sdram_enter_end)
  33 
  34         .balign 4
  35 ENTRY(ecovec24_sdram_leave_start)
  36 
  37         mov.l   @(SH_SLEEP_MODE, r5), r0
  38         tst     #SUSP_SH_RSTANDBY, r0
  39         bf      resume_rstandby
  40 
  41         /* DBSC: put memory in auto-refresh mode */
  42 
  43         ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
  44         WAIT 1
  45         ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
  46         ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
  47         ED 0xFD000010, 0x00000001 /* DBEN */
  48         ED 0xFD000040, 0x00010000 /* DBRFPDN0 */
  49 
  50         rts
  51          nop
  52 
  53 resume_rstandby:
  54 
  55         /* DBSC: re-initialize and put in auto-refresh */
  56 
  57         ED 0xFD000108, 0x00000181 /* DBPDCNT0 */
  58         ED 0xFD000020, 0x015B0002 /* DBCONF */
  59         ED 0xFD000030, 0x03071502 /* DBTR0 */
  60         ED 0xFD000034, 0x02020102 /* DBTR1 */
  61         ED 0xFD000038, 0x01090405 /* DBTR2 */
  62         ED 0xFD00003C, 0x00000002 /* DBTR3 */
  63         ED 0xFD000008, 0x00000005 /* DBKIND */
  64         ED 0xFD000040, 0x00000001 /* DBRFPDN0 */
  65         ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
  66         ED 0xFD000018, 0x00000001 /* DBCKECNT */
  67 
  68         mov     #100,r0
  69 WAIT_400NS:
  70         dt      r0
  71         bf      WAIT_400NS
  72 
  73         ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
  74         ED 0xFD000060, 0x00020000 /* DBMRCNT (EMR2) */
  75         ED 0xFD000060, 0x00030000 /* DBMRCNT (EMR3) */
  76         ED 0xFD000060, 0x00010004 /* DBMRCNT (EMR) */
  77         ED 0xFD000060, 0x00000532 /* DBMRCNT (MRS) */
  78         ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
  79         ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
  80         ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
  81         ED 0xFD000060, 0x00000432 /* DBMRCNT (MRS) */
  82         ED 0xFD000060, 0x000103c0 /* DBMRCNT (EMR) */
  83         ED 0xFD000060, 0x00010040 /* DBMRCNT (EMR) */
  84 
  85         mov     #100,r0
  86 WAIT_400NS_2:
  87         dt      r0
  88         bf      WAIT_400NS_2
  89 
  90         ED 0xFD000010, 0x00000001 /* DBEN */
  91         ED 0xFD000044, 0x0000050f /* DBRFPDN1 */
  92         ED 0xFD000048, 0x236800e6 /* DBRFPDN2 */
  93 
  94         mov.l   DUMMY,r0
  95         mov.l   @r0, r1 /* force single dummy read */
  96 
  97         ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
  98         ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
  99         ED 0xFD000108, 0x00000080 /* DBPDCNT0 */
 100         ED 0xFD000040, 0x00010000 /* DBRFPDN0 */
 101 
 102         rts
 103          nop
 104 
 105         .balign 4
 106 DUMMY:  .long   0xac400000
 107 
 108 ENTRY(ecovec24_sdram_leave_end)