sdram.S

  1/* SPDX-License-Identifier: GPL-2.0
  2 *
  3 * MS7724SE 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
 19ENTRY(ms7724se_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
 32ENTRY(ms7724se_sdram_enter_end)
 33
 34	.balign 4
 35ENTRY(ms7724se_sdram_leave_start)
 36
 37	/* DBSC: put memory in auto-refresh mode */
 38
 39	mov.l	@(SH_SLEEP_MODE, r5), r0
 40	tst	#SUSP_SH_RSTANDBY, r0
 41	bf	resume_rstandby
 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
 53resume_rstandby:
 54
 55	/* CPG: setup clocks before restarting external memory */
 56
 57	ED 0xA4150024, 0x00004000 /* PLLCR */
 58
 59	mov.l	FRQCRA,r0
 60	mov.l	@r0,r3
 61	mov.l	KICK,r1
 62	or	r1, r3
 63	mov.l	r3, @r0
 64
 65	mov.l	LSTATS,r0
 66	mov	#1,r1
 67WAIT_LSTATS:
 68	mov.l	@r0,r3
 69	tst	r1,r3
 70	bf	WAIT_LSTATS
 71
 72	/* DBSC: re-initialize and put in auto-refresh */
 73
 74	ED 0xFD000108, 0x00000181 /* DBPDCNT0 */
 75	ED 0xFD000020, 0x015B0002 /* DBCONF */
 76	ED 0xFD000030, 0x03071502 /* DBTR0 */
 77	ED 0xFD000034, 0x02020102 /* DBTR1 */
 78	ED 0xFD000038, 0x01090405 /* DBTR2 */
 79	ED 0xFD00003C, 0x00000002 /* DBTR3 */
 80	ED 0xFD000008, 0x00000005 /* DBKIND */
 81	ED 0xFD000040, 0x00000001 /* DBRFPDN0 */
 82	ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
 83	ED 0xFD000018, 0x00000001 /* DBCKECNT */
 84
 85	mov	#100,r0
 86WAIT_400NS:
 87	dt	r0
 88	bf	WAIT_400NS
 89
 90	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
 91	ED 0xFD000060, 0x00020000 /* DBMRCNT (EMR2) */
 92	ED 0xFD000060, 0x00030000 /* DBMRCNT (EMR3) */
 93	ED 0xFD000060, 0x00010004 /* DBMRCNT (EMR) */
 94	ED 0xFD000060, 0x00000532 /* DBMRCNT (MRS) */
 95	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
 96	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
 97	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
 98	ED 0xFD000060, 0x00000432 /* DBMRCNT (MRS) */
 99	ED 0xFD000060, 0x000103c0 /* DBMRCNT (EMR) */
100	ED 0xFD000060, 0x00010040 /* DBMRCNT (EMR) */
101
102	mov	#100,r0
103WAIT_400NS_2:
104	dt	r0
105	bf	WAIT_400NS_2
106
107	ED 0xFD000010, 0x00000001 /* DBEN */
108	ED 0xFD000044, 0x0000050f /* DBRFPDN1 */
109	ED 0xFD000048, 0x236800e6 /* DBRFPDN2 */
110
111	mov.l	DUMMY,r0
112	mov.l	@r0, r1 /* force single dummy read */
113
114	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
115	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
116	ED 0xFD000108, 0x00000080 /* DBPDCNT0 */
117	ED 0xFD000040, 0x00010000 /* DBRFPDN0 */
118
119	rts
120	 nop
121
122	.balign 4
123DUMMY:	.long	0xac400000
124FRQCRA:	.long	0xa4150000
125KICK:	.long	0x80000000
126LSTATS:	.long	0xa4150060
127
128ENTRY(ms7724se_sdram_leave_end)