xref: /openbmc/linux/arch/sh/boards/mach-se/7724/sdram.S (revision b2441318)
1/*
2 * MS7724SE sdram self/auto-refresh setup code
3 *
4 *  Copyright (C) 2009 Magnus Damm
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License.  See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/sys.h>
12#include <linux/errno.h>
13#include <linux/linkage.h>
14#include <asm/asm-offsets.h>
15#include <asm/suspend.h>
16#include <asm/romimage-macros.h>
17
18/* code to enter and leave self-refresh. must be self-contained.
19 * this code will be copied to on-chip memory and executed from there.
20 */
21	.balign 4
22ENTRY(ms7724se_sdram_enter_start)
23
24	/* DBSC: put memory in self-refresh mode */
25
26	ED 0xFD000010, 0x00000000 /* DBEN */
27	ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
28	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
29	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
30	ED 0xFD000040, 0x00000001 /* DBRFPDN0 */
31
32	rts
33	 nop
34
35ENTRY(ms7724se_sdram_enter_end)
36
37	.balign 4
38ENTRY(ms7724se_sdram_leave_start)
39
40	/* DBSC: put memory in auto-refresh mode */
41
42	mov.l	@(SH_SLEEP_MODE, r5), r0
43	tst	#SUSP_SH_RSTANDBY, r0
44	bf	resume_rstandby
45
46	ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
47	WAIT 1
48	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
49	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
50	ED 0xFD000010, 0x00000001 /* DBEN */
51	ED 0xFD000040, 0x00010000 /* DBRFPDN0 */
52
53	rts
54	 nop
55
56resume_rstandby:
57
58	/* CPG: setup clocks before restarting external memory */
59
60	ED 0xA4150024, 0x00004000 /* PLLCR */
61
62	mov.l	FRQCRA,r0
63	mov.l	@r0,r3
64	mov.l	KICK,r1
65	or	r1, r3
66	mov.l	r3, @r0
67
68	mov.l	LSTATS,r0
69	mov	#1,r1
70WAIT_LSTATS:
71	mov.l	@r0,r3
72	tst	r1,r3
73	bf	WAIT_LSTATS
74
75	/* DBSC: re-initialize and put in auto-refresh */
76
77	ED 0xFD000108, 0x00000181 /* DBPDCNT0 */
78	ED 0xFD000020, 0x015B0002 /* DBCONF */
79	ED 0xFD000030, 0x03071502 /* DBTR0 */
80	ED 0xFD000034, 0x02020102 /* DBTR1 */
81	ED 0xFD000038, 0x01090405 /* DBTR2 */
82	ED 0xFD00003C, 0x00000002 /* DBTR3 */
83	ED 0xFD000008, 0x00000005 /* DBKIND */
84	ED 0xFD000040, 0x00000001 /* DBRFPDN0 */
85	ED 0xFD000040, 0x00000000 /* DBRFPDN0 */
86	ED 0xFD000018, 0x00000001 /* DBCKECNT */
87
88	mov	#100,r0
89WAIT_400NS:
90	dt	r0
91	bf	WAIT_400NS
92
93	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
94	ED 0xFD000060, 0x00020000 /* DBMRCNT (EMR2) */
95	ED 0xFD000060, 0x00030000 /* DBMRCNT (EMR3) */
96	ED 0xFD000060, 0x00010004 /* DBMRCNT (EMR) */
97	ED 0xFD000060, 0x00000532 /* DBMRCNT (MRS) */
98	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
99	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
100	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
101	ED 0xFD000060, 0x00000432 /* DBMRCNT (MRS) */
102	ED 0xFD000060, 0x000103c0 /* DBMRCNT (EMR) */
103	ED 0xFD000060, 0x00010040 /* DBMRCNT (EMR) */
104
105	mov	#100,r0
106WAIT_400NS_2:
107	dt	r0
108	bf	WAIT_400NS_2
109
110	ED 0xFD000010, 0x00000001 /* DBEN */
111	ED 0xFD000044, 0x0000050f /* DBRFPDN1 */
112	ED 0xFD000048, 0x236800e6 /* DBRFPDN2 */
113
114	mov.l	DUMMY,r0
115	mov.l	@r0, r1 /* force single dummy read */
116
117	ED 0xFD000014, 0x00000002 /* DBCMDCNT (PALL) */
118	ED 0xFD000014, 0x00000004 /* DBCMDCNT (REF) */
119	ED 0xFD000108, 0x00000080 /* DBPDCNT0 */
120	ED 0xFD000040, 0x00010000 /* DBRFPDN0 */
121
122	rts
123	 nop
124
125	.balign 4
126DUMMY:	.long	0xac400000
127FRQCRA:	.long	0xa4150000
128KICK:	.long	0x80000000
129LSTATS:	.long	0xa4150060
130
131ENTRY(ms7724se_sdram_leave_end)
132