xref: /openbmc/linux/arch/arm/mach-tegra/sleep.S (revision 842ed298)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * arch/arm/mach-tegra/sleep.S
4 *
5 * Copyright (c) 2010-2011, NVIDIA Corporation.
6 * Copyright (c) 2011, Google, Inc.
7 *
8 * Author: Colin Cross <ccross@android.com>
9 *         Gary King <gking@nvidia.com>
10 */
11
12#include <linux/linkage.h>
13
14#include <asm/assembler.h>
15#include <asm/cache.h>
16#include <asm/cp15.h>
17#include <asm/hardware/cache-l2x0.h>
18
19#include "iomap.h"
20#include "sleep.h"
21
22#define CLK_RESET_CCLK_BURST	0x20
23#define CLK_RESET_CCLK_DIVIDER  0x24
24
25#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
26/*
27 * tegra_disable_clean_inv_dcache
28 *
29 * disable, clean & invalidate the D-cache
30 *
31 * Corrupted registers: r1-r3, r6, r8, r9-r11
32 */
33ENTRY(tegra_disable_clean_inv_dcache)
34	stmfd	sp!, {r0, r4-r5, r7, r9-r11, lr}
35	dmb					@ ensure ordering
36
37	/* Disable the D-cache */
38	mrc	p15, 0, r2, c1, c0, 0
39	tst	r2, #CR_C			@ see tegra_sleep_cpu()
40	bic	r2, r2, #CR_C
41	mcrne	p15, 0, r2, c1, c0, 0
42	isb
43
44	/* Flush the D-cache */
45	cmp	r0, #TEGRA_FLUSH_CACHE_ALL
46	blne	v7_flush_dcache_louis
47	bleq	v7_flush_dcache_all
48
49	/* Trun off coherency */
50	exit_smp r4, r5
51
52	ldmfd	sp!, {r0, r4-r5, r7, r9-r11, pc}
53ENDPROC(tegra_disable_clean_inv_dcache)
54#endif
55
56#ifdef CONFIG_PM_SLEEP
57/*
58 * tegra_init_l2_for_a15
59 *
60 * set up the correct L2 cache data RAM latency
61 */
62ENTRY(tegra_init_l2_for_a15)
63	mrc	p15, 0, r0, c0, c0, 5
64	ubfx	r0, r0, #8, #4
65	tst	r0, #1				@ only need for cluster 0
66	bne	_exit_init_l2_a15
67
68	mrc	p15, 0x1, r0, c9, c0, 2
69	and	r0, r0, #7
70	cmp	r0, #2
71	bicne	r0, r0, #7
72	orrne	r0, r0, #2
73	mcrne	p15, 0x1, r0, c9, c0, 2
74_exit_init_l2_a15:
75
76	ret	lr
77ENDPROC(tegra_init_l2_for_a15)
78
79/*
80 * tegra_sleep_cpu_finish(unsigned long v2p)
81 *
82 * enters suspend in LP2 by turning off the mmu and jumping to
83 * tegra?_tear_down_cpu
84 */
85ENTRY(tegra_sleep_cpu_finish)
86	mov	r4, r0
87	/* Flush and disable the L1 data cache */
88	mov	r0, #TEGRA_FLUSH_CACHE_ALL
89	bl	tegra_disable_clean_inv_dcache
90
91	mov	r0, r4
92	mov32	r6, tegra_tear_down_cpu
93	ldr	r1, [r6]
94	add	r1, r1, r0
95
96	mov32	r3, tegra_shut_off_mmu
97	add	r3, r3, r0
98	mov	r0, r1
99
100	ret	r3
101ENDPROC(tegra_sleep_cpu_finish)
102
103/*
104 * tegra_shut_off_mmu
105 *
106 * r0 = physical address to jump to with mmu off
107 *
108 * called with VA=PA mapping
109 * turns off MMU, icache, dcache and branch prediction
110 */
111	.align	L1_CACHE_SHIFT
112	.pushsection	.idmap.text, "ax"
113ENTRY(tegra_shut_off_mmu)
114	mrc	p15, 0, r3, c1, c0, 0
115	movw	r2, #CR_I | CR_Z | CR_C | CR_M
116	bic	r3, r3, r2
117	dsb
118	mcr	p15, 0, r3, c1, c0, 0
119	isb
120#ifdef CONFIG_CACHE_L2X0
121	/* Disable L2 cache */
122	check_cpu_part_num 0xc09, r9, r10
123	retne	r0
124
125	mov32	r2, TEGRA_ARM_PERIF_BASE + 0x3000
126	ldr	r3, [r2, #L2X0_CTRL]
127	tst	r3, #L2X0_CTRL_EN		@ see tegra_sleep_cpu()
128	mov	r3, #0
129	strne	r3, [r2, #L2X0_CTRL]
130#endif
131	ret	r0
132ENDPROC(tegra_shut_off_mmu)
133	.popsection
134
135/*
136 * tegra_switch_cpu_to_pllp
137 *
138 * In LP2 the normal cpu clock pllx will be turned off. Switch the CPU to pllp
139 */
140ENTRY(tegra_switch_cpu_to_pllp)
141	/* in LP2 idle (SDRAM active), set the CPU burst policy to PLLP */
142	mov32	r5, TEGRA_CLK_RESET_BASE
143	mov	r0, #(2 << 28)			@ burst policy = run mode
144	orr	r0, r0, #(4 << 4)		@ use PLLP in run mode burst
145	str	r0, [r5, #CLK_RESET_CCLK_BURST]
146	mov	r0, #0
147	str	r0, [r5, #CLK_RESET_CCLK_DIVIDER]
148	ret	lr
149ENDPROC(tegra_switch_cpu_to_pllp)
150#endif
151