summaryrefslogtreecommitdiff
path: root/arch/arm64/mm/proc.S
blob: 7783ff05f74cc262c643b1a96932a717e47445c5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
/*
 * Based on arch/arm/mm/proc.S
 *
 * Copyright (C) 2001 Deep Blue Solutions Ltd.
 * Copyright (C) 2012 ARM Ltd.
 * Author: Catalin Marinas <catalin.marinas@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>

#include "proc-macros.S"

#ifdef CONFIG_ARM64_64K_PAGES
#define TCR_TG_FLAGS	TCR_TG0_64K | TCR_TG1_64K
#else
#define TCR_TG_FLAGS	TCR_TG0_4K | TCR_TG1_4K
#endif

#define TCR_SMP_FLAGS	TCR_SHARED

/* PTWs cacheable, inner/outer WBWA */
#define TCR_CACHE_FLAGS	TCR_IRGN_WBWA | TCR_ORGN_WBWA

#define MAIR(attr, mt)	((attr) << ((mt) * 8))

/*
 *	cpu_do_idle()
 *
 *	Idle the processor (wait for interrupt).
 */
ENTRY(cpu_do_idle)
	dsb	sy				// WFI may enter a low-power mode
	wfi
	ret
ENDPROC(cpu_do_idle)

#ifdef CONFIG_CPU_PM
/**
 * cpu_do_suspend - save CPU registers context
 *
 * x0: virtual address of context pointer
 */
ENTRY(cpu_do_suspend)
	mrs	x2, tpidr_el0
	mrs	x3, tpidrro_el0
	mrs	x4, contextidr_el1
	mrs	x5, mair_el1
	mrs	x6, cpacr_el1
	mrs	x7, ttbr1_el1
	mrs	x8, tcr_el1
	mrs	x9, vbar_el1
	mrs	x10, mdscr_el1
	mrs	x11, oslsr_el1
	mrs	x12, sctlr_el1
	stp	x2, x3, [x0]
	stp	x4, x5, [x0, #16]
	stp	x6, x7, [x0, #32]
	stp	x8, x9, [x0, #48]
	stp	x10, x11, [x0, #64]
	str	x12, [x0, #80]
	ret
ENDPROC(cpu_do_suspend)

/**
 * cpu_do_resume - restore CPU register context
 *
 * x0: Physical address of context pointer
 * x1: ttbr0_el1 to be restored
 *
 * Returns:
 *	sctlr_el1 value in x0
 */
ENTRY(cpu_do_resume)
	/*
	 * Invalidate local tlb entries before turning on MMU
	 */
	tlbi	vmalle1
	ldp	x2, x3, [x0]
	ldp	x4, x5, [x0, #16]
	ldp	x6, x7, [x0, #32]
	ldp	x8, x9, [x0, #48]
	ldp	x10, x11, [x0, #64]
	ldr	x12, [x0, #80]
	msr	tpidr_el0, x2
	msr	tpidrro_el0, x3
	msr	contextidr_el1, x4
	msr	mair_el1, x5
	msr	cpacr_el1, x6
	msr	ttbr0_el1, x1
	msr	ttbr1_el1, x7
	tcr_set_idmap_t0sz x8, x7
	msr	tcr_el1, x8
	msr	vbar_el1, x9
	msr	mdscr_el1, x10
	/*
	 * Restore oslsr_el1 by writing oslar_el1
	 */
	ubfx	x11, x11, #1, #1
	msr	oslar_el1, x11
	mov	x0, x12
	dsb	nsh		// Make sure local tlb invalidation completed
	isb
	ret
ENDPROC(cpu_do_resume)
#endif

/*
 *	cpu_do_switch_mm(pgd_phys, tsk)
 *
 *	Set the translation table base pointer to be pgd_phys.
 *
 *	- pgd_phys - physical address of new TTB
 */
ENTRY(cpu_do_switch_mm)
	mmid	w1, x1				// get mm->context.id
	bfi	x0, x1, #48, #16		// set the ASID
	msr	ttbr0_el1, x0			// set TTBR0
	isb
	ret
ENDPROC(cpu_do_switch_mm)

	.section ".text.init", #alloc, #execinstr

/*
 *	__cpu_setup
 *
 *	Initialise the processor for turning the MMU on.  Return in x0 the
 *	value of the SCTLR_EL1 register.
 */
ENTRY(__cpu_setup)
	tlbi	vmalle1is			// invalidate I + D TLBs
	dsb	ish

	mov	x0, #3 << 20
	msr	cpacr_el1, x0			// Enable FP/ASIMD
	mov	x0, #1 << 12			// Reset mdscr_el1 and disable
	msr	mdscr_el1, x0			// access to the DCC from EL0
	/*
	 * Memory region attributes for LPAE:
	 *
	 *   n = AttrIndx[2:0]
	 *			n	MAIR
	 *   DEVICE_nGnRnE	000	00000000
	 *   DEVICE_nGnRE	001	00000100
	 *   DEVICE_GRE		010	00001100
	 *   NORMAL_NC		011	01000100
	 *   NORMAL		100	11111111
	 *   NORMAL_WT		101	10111011
	 */
	ldr	x5, =MAIR(0x00, MT_DEVICE_nGnRnE) | \
		     MAIR(0x04, MT_DEVICE_nGnRE) | \
		     MAIR(0x0c, MT_DEVICE_GRE) | \
		     MAIR(0x44, MT_NORMAL_NC) | \
		     MAIR(0xff, MT_NORMAL) | \
		     MAIR(0xbb, MT_NORMAL_WT)
	msr	mair_el1, x5
	/*
	 * Prepare SCTLR
	 */
	adr	x5, crval
	ldp	w5, w6, [x5]
	mrs	x0, sctlr_el1
	bic	x0, x0, x5			// clear bits
	orr	x0, x0, x6			// set bits
	/*
	 * Set/prepare TCR and TTBR. We use 512GB (39-bit) address range for
	 * both user and kernel.
	 */
	ldr	x10, =TCR_TxSZ(VA_BITS) | TCR_CACHE_FLAGS | TCR_SMP_FLAGS | \
			TCR_TG_FLAGS | TCR_ASID16 | TCR_TBI0
	tcr_set_idmap_t0sz	x10, x9

	/*
	 * Read the PARange bits from ID_AA64MMFR0_EL1 and set the IPS bits in
	 * TCR_EL1.
	 */
	mrs	x9, ID_AA64MMFR0_EL1
	bfi	x10, x9, #32, #3
#ifdef CONFIG_ARM64_HW_AFDBM
	/*
	 * Hardware update of the Access and Dirty bits.
	 */
	mrs	x9, ID_AA64MMFR1_EL1
	and	x9, x9, #0xf
	cbz	x9, 2f
	cmp	x9, #2
	b.lt	1f
	orr	x10, x10, #TCR_HD		// hardware Dirty flag update
1:	orr	x10, x10, #TCR_HA		// hardware Access flag update
2:
#endif	/* CONFIG_ARM64_HW_AFDBM */
	msr	tcr_el1, x10
	ret					// return to head.S
ENDPROC(__cpu_setup)

	/*
	 * We set the desired value explicitly, including those of the
	 * reserved bits. The values of bits EE & E0E were set early in
	 * el2_setup, which are left untouched below.
	 *
	 *                 n n            T
	 *       U E      WT T UD     US IHBS
	 *       CE0      XWHW CZ     ME TEEA S
	 * .... .IEE .... NEAI TE.I ..AD DEN0 ACAM
	 * 0011 0... 1101 ..0. ..0. 10.. .0.. .... < hardware reserved
	 * .... .1.. .... 01.1 11.1 ..01 0.01 1101 < software settings
	 */
	.type	crval, #object
crval:
	.word	0xfcffffff			// clear
	.word	0x34d5d91d			// set