xref: /openbmc/linux/arch/arm/mach-omap1/sleep.S (revision 7effbd18) 
1/*
2 * linux/arch/arm/mach-omap1/sleep.S
3 *
4 * Low-level OMAP7XX/1510/1610 sleep/wakeUp support
5 *
6 * Initial SA1110 code:
7 * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
8 *
9 * Adapted for PXA by Nicolas Pitre:
10 * Copyright (c) 2002 Monta Vista Software, Inc.
11 *
12 * Support for OMAP1510/1610 by Dirk Behme <dirk.behme@de.bosch.com>
13 *
14 * This program is free software; you can redistribute it and/or modify it
15 * under the terms of the GNU General Public License as published by the
16 * Free Software Foundation; either version 2 of the License, or (at your
17 * option) any later version.
18 *
19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
22 * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
25 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
26 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 *
30 * You should have received a copy of the GNU General Public License along
31 * with this program; if not, write to the Free Software Foundation, Inc.,
32 * 675 Mass Ave, Cambridge, MA 02139, USA.
33 */
34
35#include <linux/linkage.h>
36
37#include <asm/assembler.h>
38
39#include "hardware.h"
40
41#include "iomap.h"
42#include "pm.h"
43
44		.text
45
46
47/*
48 * Forces OMAP into deep sleep state
49 *
50 * omapXXXX_cpu_suspend()
51 *
52 * The values of the registers ARM_IDLECT1 and ARM_IDLECT2 are passed
53 * as arg0 and arg1 from caller. arg0 is stored in register r0 and arg1
54 * in register r1.
55 *
56 * Note: This code get's copied to internal SRAM at boot. When the OMAP
57 *	 wakes up it continues execution at the point it went to sleep.
58 *
59 * Note: Because of errata work arounds we have processor specific functions
60 *       here. They are mostly the same, but slightly different.
61 *
62 */
63
64#ifdef CONFIG_ARCH_OMAP15XX
65	.align	3
66ENTRY(omap1510_cpu_suspend)
67
68	@ save registers on stack
69	stmfd	sp!, {r0 - r12, lr}
70
71	@ load base address of Traffic Controller
72	mov	r4, #TCMIF_ASM_BASE & 0xff000000
73	orr	r4, r4, #TCMIF_ASM_BASE & 0x00ff0000
74	orr	r4, r4, #TCMIF_ASM_BASE & 0x0000ff00
75
76	@ work around errata of OMAP1510 PDE bit for TC shut down
77	@ clear PDE bit
78	ldr	r5, [r4, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
79	bic	r5, r5, #PDE_BIT & 0xff
80	str	r5, [r4, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
81
82	@ set PWD_EN bit
83	and	r5, r5, #PWD_EN_BIT & 0xff
84	str	r5, [r4, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
85
86	@ prepare to put SDRAM into self-refresh manually
87	ldr	r5, [r4, #EMIFF_SDRAM_CONFIG_ASM_OFFSET & 0xff]
88	orr	r5, r5, #SELF_REFRESH_MODE & 0xff000000
89	orr	r5, r5, #SELF_REFRESH_MODE & 0x000000ff
90	str	r5, [r4, #EMIFF_SDRAM_CONFIG_ASM_OFFSET & 0xff]
91
92	@ prepare to put EMIFS to Sleep
93	ldr	r5, [r4, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
94	orr	r5, r5, #IDLE_EMIFS_REQUEST & 0xff
95	str	r5, [r4, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
96
97	@ load base address of ARM_IDLECT1 and ARM_IDLECT2
98	mov	r4, #CLKGEN_REG_ASM_BASE & 0xff000000
99	orr	r4, r4, #CLKGEN_REG_ASM_BASE & 0x00ff0000
100	orr	r4, r4, #CLKGEN_REG_ASM_BASE & 0x0000ff00
101
102	@ turn off clock domains
103	mov	r5, #OMAP1510_IDLE_CLOCK_DOMAINS & 0xff
104	orr	r5, r5, #OMAP1510_IDLE_CLOCK_DOMAINS & 0xff00
105	strh	r5, [r4, #ARM_IDLECT2_ASM_OFFSET & 0xff]
106
107	@ request ARM idle
108	mov	r3, #OMAP1510_DEEP_SLEEP_REQUEST & 0xff
109	orr	r3, r3, #OMAP1510_DEEP_SLEEP_REQUEST & 0xff00
110	strh	r3, [r4, #ARM_IDLECT1_ASM_OFFSET & 0xff]
111
112	mov	r5, #IDLE_WAIT_CYCLES & 0xff
113	orr	r5, r5, #IDLE_WAIT_CYCLES & 0xff00
114l_1510_2:
115	subs	r5, r5, #1
116	bne	l_1510_2
117/*
118 * Let's wait for the next wake up event to wake us up. r0 can't be
119 * used here because r0 holds ARM_IDLECT1
120 */
121	mov	r2, #0
122	mcr	p15, 0, r2, c7, c0, 4		@ wait for interrupt
123/*
124 * omap1510_cpu_suspend()'s resume point.
125 *
126 * It will just start executing here, so we'll restore stuff from the
127 * stack, reset the ARM_IDLECT1 and ARM_IDLECT2.
128 */
129	strh	r1, [r4, #ARM_IDLECT2_ASM_OFFSET & 0xff]
130	strh	r0, [r4, #ARM_IDLECT1_ASM_OFFSET & 0xff]
131
132	@ restore regs and return
133	ldmfd	sp!, {r0 - r12, pc}
134
135ENTRY(omap1510_cpu_suspend_sz)
136	.word	. - omap1510_cpu_suspend
137#endif /* CONFIG_ARCH_OMAP15XX */
138
139#if defined(CONFIG_ARCH_OMAP16XX)
140	.align	3
141ENTRY(omap1610_cpu_suspend)
142
143	@ save registers on stack
144	stmfd	sp!, {r0 - r12, lr}
145
146	@ Drain write cache
147	mov	r4, #0
148	mcr	p15, 0, r0, c7, c10, 4
149	nop
150
151	@ Load base address of Traffic Controller
152	mov	r6, #TCMIF_ASM_BASE & 0xff000000
153	orr	r6, r6, #TCMIF_ASM_BASE & 0x00ff0000
154	orr	r6, r6, #TCMIF_ASM_BASE & 0x0000ff00
155
156	@ Prepare to put SDRAM into self-refresh manually
157	ldr	r7, [r6, #EMIFF_SDRAM_CONFIG_ASM_OFFSET & 0xff]
158	orr	r9, r7, #SELF_REFRESH_MODE & 0xff000000
159	orr	r9, r9, #SELF_REFRESH_MODE & 0x000000ff
160	str	r9, [r6, #EMIFF_SDRAM_CONFIG_ASM_OFFSET & 0xff]
161
162	@ Prepare to put EMIFS to Sleep
163	ldr	r8, [r6, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
164	orr	r9, r8, #IDLE_EMIFS_REQUEST & 0xff
165	str	r9, [r6, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
166
167	@ Load base address of ARM_IDLECT1 and ARM_IDLECT2
168	mov	r4, #CLKGEN_REG_ASM_BASE & 0xff000000
169	orr	r4, r4, #CLKGEN_REG_ASM_BASE & 0x00ff0000
170	orr	r4, r4, #CLKGEN_REG_ASM_BASE & 0x0000ff00
171
172	@ Turn off clock domains
173	@ Do not disable PERCK (0x04)
174	mov	r5, #OMAP1610_IDLECT2_SLEEP_VAL & 0xff
175	orr	r5, r5, #OMAP1610_IDLECT2_SLEEP_VAL & 0xff00
176	strh	r5, [r4, #ARM_IDLECT2_ASM_OFFSET & 0xff]
177
178	@ Request ARM idle
179	mov	r3, #OMAP1610_IDLECT1_SLEEP_VAL & 0xff
180	orr	r3, r3, #OMAP1610_IDLECT1_SLEEP_VAL & 0xff00
181	strh	r3, [r4, #ARM_IDLECT1_ASM_OFFSET & 0xff]
182
183/*
184 * Let's wait for the next wake up event to wake us up. r0 can't be
185 * used here because r0 holds ARM_IDLECT1
186 */
187	mov	r2, #0
188	mcr	p15, 0, r2, c7, c0, 4		@ wait for interrupt
189
190	@ Errata (HEL3SU467, section 1.4.4) specifies nop-instructions
191	@ according to this formula:
192	@ 2 + (4*DPLL_MULT)/DPLL_DIV/ARMDIV
193	@ Max DPLL_MULT = 18
194	@ DPLL_DIV = 1
195	@ ARMDIV = 1
196	@ => 74 nop-instructions
197	nop
198	nop
199	nop
200	nop
201	nop
202	nop
203	nop
204	nop
205	nop
206	nop	@10
207	nop
208	nop
209	nop
210	nop
211	nop
212	nop
213	nop
214	nop
215	nop
216	nop	@20
217	nop
218	nop
219	nop
220	nop
221	nop
222	nop
223	nop
224	nop
225	nop
226	nop	@30
227	nop
228	nop
229	nop
230	nop
231	nop
232	nop
233	nop
234	nop
235	nop
236	nop	@40
237	nop
238	nop
239	nop
240	nop
241	nop
242	nop
243	nop
244	nop
245	nop
246	nop	@50
247	nop
248	nop
249	nop
250	nop
251	nop
252	nop
253	nop
254	nop
255	nop
256	nop	@60
257	nop
258	nop
259	nop
260	nop
261	nop
262	nop
263	nop
264	nop
265	nop
266	nop	@70
267	nop
268	nop
269	nop
270	nop	@74
271/*
272 * omap1610_cpu_suspend()'s resume point.
273 *
274 * It will just start executing here, so we'll restore stuff from the
275 * stack.
276 */
277	@ Restore the ARM_IDLECT1 and ARM_IDLECT2.
278	strh	r1, [r4, #ARM_IDLECT2_ASM_OFFSET & 0xff]
279	strh	r0, [r4, #ARM_IDLECT1_ASM_OFFSET & 0xff]
280
281	@ Restore EMIFF controls
282	str	r7, [r6, #EMIFF_SDRAM_CONFIG_ASM_OFFSET & 0xff]
283	str	r8, [r6, #EMIFS_CONFIG_ASM_OFFSET & 0xff]
284
285	@ Restore regs and return
286	ldmfd	sp!, {r0 - r12, pc}
287
288ENTRY(omap1610_cpu_suspend_sz)
289	.word	. - omap1610_cpu_suspend
290#endif /* CONFIG_ARCH_OMAP16XX */
291