xref: /openbmc/linux/arch/arm/mach-tegra/sleep.S (revision 6d99a79c)
1/*
2 * arch/arm/mach-tegra/sleep.S
3 *
4 * Copyright (c) 2010-2011, NVIDIA Corporation.
5 * Copyright (c) 2011, Google, Inc.
6 *
7 * Author: Colin Cross <ccross@android.com>
8 *         Gary King <gking@nvidia.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
17 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
18 * more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
23 */
24
25#include <linux/linkage.h>
26
27#include <asm/assembler.h>
28#include <asm/cache.h>
29#include <asm/cp15.h>
30#include <asm/hardware/cache-l2x0.h>
31
32#include "iomap.h"
33#include "sleep.h"
34
35#define CLK_RESET_CCLK_BURST	0x20
36#define CLK_RESET_CCLK_DIVIDER  0x24
37
38#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
39/*
40 * tegra_disable_clean_inv_dcache
41 *
42 * disable, clean & invalidate the D-cache
43 *
44 * Corrupted registers: r1-r3, r6, r8, r9-r11
45 */
46ENTRY(tegra_disable_clean_inv_dcache)
47	stmfd	sp!, {r0, r4-r5, r7, r9-r11, lr}
48	dmb					@ ensure ordering
49
50	/* Disable the D-cache */
51	mrc	p15, 0, r2, c1, c0, 0
52	bic	r2, r2, #CR_C
53	mcr	p15, 0, r2, c1, c0, 0
54	isb
55
56	/* Flush the D-cache */
57	cmp	r0, #TEGRA_FLUSH_CACHE_ALL
58	blne	v7_flush_dcache_louis
59	bleq	v7_flush_dcache_all
60
61	/* Trun off coherency */
62	exit_smp r4, r5
63
64	ldmfd	sp!, {r0, r4-r5, r7, r9-r11, pc}
65ENDPROC(tegra_disable_clean_inv_dcache)
66#endif
67
68#ifdef CONFIG_PM_SLEEP
69/*
70 * tegra_init_l2_for_a15
71 *
72 * set up the correct L2 cache data RAM latency
73 */
74ENTRY(tegra_init_l2_for_a15)
75	mrc	p15, 0, r0, c0, c0, 5
76	ubfx	r0, r0, #8, #4
77	tst	r0, #1				@ only need for cluster 0
78	bne	_exit_init_l2_a15
79
80	mrc	p15, 0x1, r0, c9, c0, 2
81	and	r0, r0, #7
82	cmp	r0, #2
83	bicne	r0, r0, #7
84	orrne	r0, r0, #2
85	mcrne	p15, 0x1, r0, c9, c0, 2
86_exit_init_l2_a15:
87
88	ret	lr
89ENDPROC(tegra_init_l2_for_a15)
90
91/*
92 * tegra_sleep_cpu_finish(unsigned long v2p)
93 *
94 * enters suspend in LP2 by turning off the mmu and jumping to
95 * tegra?_tear_down_cpu
96 */
97ENTRY(tegra_sleep_cpu_finish)
98	mov	r4, r0
99	/* Flush and disable the L1 data cache */
100	mov	r0, #TEGRA_FLUSH_CACHE_ALL
101	bl	tegra_disable_clean_inv_dcache
102
103	mov	r0, r4
104	mov32	r6, tegra_tear_down_cpu
105	ldr	r1, [r6]
106	add	r1, r1, r0
107
108	mov32	r3, tegra_shut_off_mmu
109	add	r3, r3, r0
110	mov	r0, r1
111
112	ret	r3
113ENDPROC(tegra_sleep_cpu_finish)
114
115/*
116 * tegra_shut_off_mmu
117 *
118 * r0 = physical address to jump to with mmu off
119 *
120 * called with VA=PA mapping
121 * turns off MMU, icache, dcache and branch prediction
122 */
123	.align	L1_CACHE_SHIFT
124	.pushsection	.idmap.text, "ax"
125ENTRY(tegra_shut_off_mmu)
126	mrc	p15, 0, r3, c1, c0, 0
127	movw	r2, #CR_I | CR_Z | CR_C | CR_M
128	bic	r3, r3, r2
129	dsb
130	mcr	p15, 0, r3, c1, c0, 0
131	isb
132#ifdef CONFIG_CACHE_L2X0
133	/* Disable L2 cache */
134	check_cpu_part_num 0xc09, r9, r10
135	movweq	r2, #:lower16:(TEGRA_ARM_PERIF_BASE + 0x3000)
136	movteq	r2, #:upper16:(TEGRA_ARM_PERIF_BASE + 0x3000)
137	moveq	r3, #0
138	streq	r3, [r2, #L2X0_CTRL]
139#endif
140	ret	r0
141ENDPROC(tegra_shut_off_mmu)
142	.popsection
143
144/*
145 * tegra_switch_cpu_to_pllp
146 *
147 * In LP2 the normal cpu clock pllx will be turned off. Switch the CPU to pllp
148 */
149ENTRY(tegra_switch_cpu_to_pllp)
150	/* in LP2 idle (SDRAM active), set the CPU burst policy to PLLP */
151	mov32	r5, TEGRA_CLK_RESET_BASE
152	mov	r0, #(2 << 28)			@ burst policy = run mode
153	orr	r0, r0, #(4 << 4)		@ use PLLP in run mode burst
154	str	r0, [r5, #CLK_RESET_CCLK_BURST]
155	mov	r0, #0
156	str	r0, [r5, #CLK_RESET_CCLK_DIVIDER]
157	ret	lr
158ENDPROC(tegra_switch_cpu_to_pllp)
159#endif
160