xref: /openbmc/linux/arch/arm/mach-tegra/sleep.S (revision 7b6d864b)
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
34#include "flowctrl.h"
35#include "sleep.h"
36
37#define CLK_RESET_CCLK_BURST	0x20
38#define CLK_RESET_CCLK_DIVIDER  0x24
39
40#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
41/*
42 * tegra_disable_clean_inv_dcache
43 *
44 * disable, clean & invalidate the D-cache
45 *
46 * Corrupted registers: r1-r3, r6, r8, r9-r11
47 */
48ENTRY(tegra_disable_clean_inv_dcache)
49	stmfd	sp!, {r0, r4-r5, r7, r9-r11, lr}
50	dmb					@ ensure ordering
51
52	/* Disable the D-cache */
53	mrc	p15, 0, r2, c1, c0, 0
54	bic	r2, r2, #CR_C
55	mcr	p15, 0, r2, c1, c0, 0
56	isb
57
58	/* Flush the D-cache */
59	bl	v7_flush_dcache_louis
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_sleep_cpu_finish(unsigned long v2p)
71 *
72 * enters suspend in LP2 by turning off the mmu and jumping to
73 * tegra?_tear_down_cpu
74 */
75ENTRY(tegra_sleep_cpu_finish)
76	/* Flush and disable the L1 data cache */
77	bl	tegra_disable_clean_inv_dcache
78
79	mov32	r6, tegra_tear_down_cpu
80	ldr	r1, [r6]
81	add	r1, r1, r0
82
83	mov32	r3, tegra_shut_off_mmu
84	add	r3, r3, r0
85	mov	r0, r1
86
87	mov	pc, r3
88ENDPROC(tegra_sleep_cpu_finish)
89
90/*
91 * tegra_shut_off_mmu
92 *
93 * r0 = physical address to jump to with mmu off
94 *
95 * called with VA=PA mapping
96 * turns off MMU, icache, dcache and branch prediction
97 */
98	.align	L1_CACHE_SHIFT
99	.pushsection	.idmap.text, "ax"
100ENTRY(tegra_shut_off_mmu)
101	mrc	p15, 0, r3, c1, c0, 0
102	movw	r2, #CR_I | CR_Z | CR_C | CR_M
103	bic	r3, r3, r2
104	dsb
105	mcr	p15, 0, r3, c1, c0, 0
106	isb
107#ifdef CONFIG_CACHE_L2X0
108	/* Disable L2 cache */
109	check_cpu_part_num 0xc09, r9, r10
110	movweq	r4, #:lower16:(TEGRA_ARM_PERIF_BASE + 0x3000)
111	movteq	r4, #:upper16:(TEGRA_ARM_PERIF_BASE + 0x3000)
112	moveq	r5, #0
113	streq	r5, [r4, #L2X0_CTRL]
114#endif
115	mov	pc, r0
116ENDPROC(tegra_shut_off_mmu)
117	.popsection
118
119/*
120 * tegra_switch_cpu_to_pllp
121 *
122 * In LP2 the normal cpu clock pllx will be turned off. Switch the CPU to pllp
123 */
124ENTRY(tegra_switch_cpu_to_pllp)
125	/* in LP2 idle (SDRAM active), set the CPU burst policy to PLLP */
126	mov32	r5, TEGRA_CLK_RESET_BASE
127	mov	r0, #(2 << 28)			@ burst policy = run mode
128	orr	r0, r0, #(4 << 4)		@ use PLLP in run mode burst
129	str	r0, [r5, #CLK_RESET_CCLK_BURST]
130	mov	r0, #0
131	str	r0, [r5, #CLK_RESET_CCLK_DIVIDER]
132	mov	pc, lr
133ENDPROC(tegra_switch_cpu_to_pllp)
134#endif
135