summaryrefslogtreecommitdiffstats
path: root/arch/arm/mm/proc-v6.S
blob: 203dff89ab1abd769ace8009279b09393faad635 (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
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  linux/arch/arm/mm/proc-v6.S
 *
 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
 *  Modified by Catalin Marinas for noMMU support
 *
 *  This is the "shell" of the ARMv6 processor support.
 */
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/pgtable.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>

#include "proc-macros.S"

#define D_CACHE_LINE_SIZE	32

#define TTB_C		(1 << 0)
#define TTB_S		(1 << 1)
#define TTB_IMP		(1 << 2)
#define TTB_RGN_NC	(0 << 3)
#define TTB_RGN_WBWA	(1 << 3)
#define TTB_RGN_WT	(2 << 3)
#define TTB_RGN_WB	(3 << 3)

#define TTB_FLAGS_UP	TTB_RGN_WBWA
#define PMD_FLAGS_UP	PMD_SECT_WB
#define TTB_FLAGS_SMP	TTB_RGN_WBWA|TTB_S
#define PMD_FLAGS_SMP	PMD_SECT_WBWA|PMD_SECT_S

.arch armv6

ENTRY(cpu_v6_proc_init)
	ret	lr

ENTRY(cpu_v6_proc_fin)
	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
	bic	r0, r0, #0x1000			@ ...i............
	bic	r0, r0, #0x0006			@ .............ca.
	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
	ret	lr

/*
 *	cpu_v6_reset(loc)
 *
 *	Perform a soft reset of the system.  Put the CPU into the
 *	same state as it would be if it had been reset, and branch
 *	to what would be the reset vector.
 *
 *	- loc   - location to jump to for soft reset
 */
	.align	5
	.pushsection	.idmap.text, "ax"
ENTRY(cpu_v6_reset)
	mrc	p15, 0, r1, c1, c0, 0		@ ctrl register
	bic	r1, r1, #0x1			@ ...............m
	mcr	p15, 0, r1, c1, c0, 0		@ disable MMU
	mov	r1, #0
	mcr	p15, 0, r1, c7, c5, 4		@ ISB
	ret	r0
ENDPROC(cpu_v6_reset)
	.popsection

/*
 *	cpu_v6_do_idle()
 *
 *	Idle the processor (eg, wait for interrupt).
 *
 *	IRQs are already disabled.
 */
ENTRY(cpu_v6_do_idle)
	mov	r1, #0
	mcr	p15, 0, r1, c7, c10, 4		@ DWB - WFI may enter a low-power mode
	mcr	p15, 0, r1, c7, c0, 4		@ wait for interrupt
	ret	lr

ENTRY(cpu_v6_dcache_clean_area)
1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
	add	r0, r0, #D_CACHE_LINE_SIZE
	subs	r1, r1, #D_CACHE_LINE_SIZE
	bhi	1b
	ret	lr

/*
 *	cpu_v6_switch_mm(pgd_phys, tsk)
 *
 *	Set the translation table base pointer to be pgd_phys
 *
 *	- pgd_phys - physical address of new TTB
 *
 *	It is assumed that:
 *	- we are not using split page tables
 */
ENTRY(cpu_v6_switch_mm)
#ifdef CONFIG_MMU
	mov	r2, #0
	mmid	r1, r1				@ get mm->context.id
	ALT_SMP(orr	r0, r0, #TTB_FLAGS_SMP)
	ALT_UP(orr	r0, r0, #TTB_FLAGS_UP)
	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB
	mcr	p15, 0, r2, c7, c10, 4		@ drain write buffer
	mcr	p15, 0, r0, c2, c0, 0		@ set TTB 0
#ifdef CONFIG_PID_IN_CONTEXTIDR
	mrc	p15, 0, r2, c13, c0, 1		@ read current context ID
	bic	r2, r2, #0xff			@ extract the PID
	and	r1, r1, #0xff
	orr	r1, r1, r2			@ insert into new context ID
#endif
	mcr	p15, 0, r1, c13, c0, 1		@ set context ID
#endif
	ret	lr

/*
 *	cpu_v6_set_pte_ext(ptep, pte, ext)
 *
 *	Set a level 2 translation table entry.
 *
 *	- ptep  - pointer to level 2 translation table entry
 *		  (hardware version is stored at -1024 bytes)
 *	- pte   - PTE value to store
 *	- ext	- value for extended PTE bits
 */
	armv6_mt_table cpu_v6

ENTRY(cpu_v6_set_pte_ext)
#ifdef CONFIG_MMU
	armv6_set_pte_ext cpu_v6
#endif
	ret	lr

/* Suspend/resume support: taken from arch/arm/mach-s3c64xx/sleep.S */
.globl	cpu_v6_suspend_size
.equ	cpu_v6_suspend_size, 4 * 6
#ifdef CONFIG_ARM_CPU_SUSPEND
ENTRY(cpu_v6_do_suspend)
	stmfd	sp!, {r4 - r9, lr}
	mrc	p15, 0, r4, c13, c0, 0	@ FCSE/PID
#ifdef CONFIG_MMU
	mrc	p15, 0, r5, c3, c0, 0	@ Domain ID
	mrc	p15, 0, r6, c2, c0, 1	@ Translation table base 1
#endif
	mrc	p15, 0, r7, c1, c0, 1	@ auxiliary control register
	mrc	p15, 0, r8, c1, c0, 2	@ co-processor access control
	mrc	p15, 0, r9, c1, c0, 0	@ control register
	stmia	r0, {r4 - r9}
	ldmfd	sp!, {r4- r9, pc}
ENDPROC(cpu_v6_do_suspend)

ENTRY(cpu_v6_do_resume)
	mov	ip, #0
	mcr	p15, 0, ip, c7, c14, 0	@ clean+invalidate D cache
	mcr	p15, 0, ip, c7, c5, 0	@ invalidate I cache
	mcr	p15, 0, ip, c7, c15, 0	@ clean+invalidate cache
	mcr	p15, 0, ip, c7, c10, 4	@ drain write buffer
	mcr	p15, 0, ip, c13, c0, 1	@ set reserved context ID
	ldmia	r0, {r4 - r9}
	mcr	p15, 0, r4, c13, c0, 0	@ FCSE/PID
#ifdef CONFIG_MMU
	mcr	p15, 0, r5, c3, c0, 0	@ Domain ID
	ALT_SMP(orr	r1, r1, #TTB_FLAGS_SMP)
	ALT_UP(orr	r1, r1, #TTB_FLAGS_UP)
	mcr	p15, 0, r1, c2, c0, 0	@ Translation table base 0
	mcr	p15, 0, r6, c2, c0, 1	@ Translation table base 1
	mcr	p15, 0, ip, c2, c0, 2	@ TTB control register
#endif
	mcr	p15, 0, r7, c1, c0, 1	@ auxiliary control register
	mcr	p15, 0, r8, c1, c0, 2	@ co-processor access control
	mcr	p15, 0, ip, c7, c5, 4	@ ISB
	mov	r0, r9			@ control register
	b	cpu_resume_mmu
ENDPROC(cpu_v6_do_resume)
#endif

	string	cpu_v6_name, "ARMv6-compatible processor"

	.align

/*
 *	__v6_setup
 *
 *	Initialise TLB, Caches, and MMU state ready to switch the MMU
 *	on.  Return in r0 the new CP15 C1 control register setting.
 *
 *	We automatically detect if we have a Harvard cache, and use the
 *	Harvard cache control instructions insead of the unified cache
 *	control instructions.
 *
 *	This should be able to cover all ARMv6 cores.
 *
 *	It is assumed that:
 *	- cache type register is implemented
 */
__v6_setup:
#ifdef CONFIG_SMP
	ALT_SMP(mrc	p15, 0, r0, c1, c0, 1)	@ Enable SMP/nAMP mode
	ALT_UP(nop)
	orr	r0, r0, #0x20
	ALT_SMP(mcr	p15, 0, r0, c1, c0, 1)
	ALT_UP(nop)
#endif

	mov	r0, #0
	mcr	p15, 0, r0, c7, c14, 0		@ clean+invalidate D cache
	mcr	p15, 0, r0, c7, c5, 0		@ invalidate I cache
	mcr	p15, 0, r0, c7, c15, 0		@ clean+invalidate cache
#ifdef CONFIG_MMU
	mcr	p15, 0, r0, c8, c7, 0		@ invalidate I + D TLBs
	mcr	p15, 0, r0, c2, c0, 2		@ TTB control register
	ALT_SMP(orr	r4, r4, #TTB_FLAGS_SMP)
	ALT_UP(orr	r4, r4, #TTB_FLAGS_UP)
	ALT_SMP(orr	r8, r8, #TTB_FLAGS_SMP)
	ALT_UP(orr	r8, r8, #TTB_FLAGS_UP)
	mcr	p15, 0, r8, c2, c0, 1		@ load TTB1
#endif /* CONFIG_MMU */
	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer and
						@ complete invalidations
	adr	r5, v6_crval
	ldmia	r5, {r5, r6}
 ARM_BE8(orr	r6, r6, #1 << 25)		@ big-endian page tables
	mrc	p15, 0, r0, c1, c0, 0		@ read control register
	bic	r0, r0, r5			@ clear bits them
	orr	r0, r0, r6			@ set them
#ifdef CONFIG_ARM_ERRATA_364296
	/*
	 * Workaround for the 364296 ARM1136 r0p2 erratum (possible cache data
	 * corruption with hit-under-miss enabled). The conditional code below
	 * (setting the undocumented bit 31 in the auxiliary control register
	 * and the FI bit in the control register) disables hit-under-miss
	 * without putting the processor into full low interrupt latency mode.
	 */
	ldr	r6, =0x4107b362			@ id for ARM1136 r0p2
	mrc	p15, 0, r5, c0, c0, 0		@ get processor id
	teq	r5, r6				@ check for the faulty core
	mrceq	p15, 0, r5, c1, c0, 1		@ load aux control reg
	orreq	r5, r5, #(1 << 31)		@ set the undocumented bit 31
	mcreq	p15, 0, r5, c1, c0, 1		@ write aux control reg
	orreq	r0, r0, #(1 << 21)		@ low interrupt latency configuration
#endif
	ret	lr				@ return to head.S:__ret

	/*
	 *         V X F   I D LR
	 * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
	 * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
	 *         0 110       0011 1.00 .111 1101 < we want
	 */
	.type	v6_crval, #object
v6_crval:
	crval	clear=0x01e0fb7f, mmuset=0x00c0387d, ucset=0x00c0187c

	__INITDATA

	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
	define_processor_functions v6, dabort=v6_early_abort, pabort=v6_pabort, suspend=1

	.section ".rodata"

	string	cpu_arch_name, "armv6"
	string	cpu_elf_name, "v6"
	.align

	.section ".proc.info.init", "a"

	/*
	 * Match any ARMv6 processor core.
	 */
	.type	__v6_proc_info, #object
__v6_proc_info:
	.long	0x0007b000
	.long	0x0007f000
	ALT_SMP(.long \
		PMD_TYPE_SECT | \
		PMD_SECT_AP_WRITE | \
		PMD_SECT_AP_READ | \
		PMD_FLAGS_SMP)
	ALT_UP(.long \
		PMD_TYPE_SECT | \
		PMD_SECT_AP_WRITE | \
		PMD_SECT_AP_READ | \
		PMD_FLAGS_UP)
	.long   PMD_TYPE_SECT | \
		PMD_SECT_XN | \
		PMD_SECT_AP_WRITE | \
		PMD_SECT_AP_READ
	initfn	__v6_setup, __v6_proc_info
	.long	cpu_arch_name
	.long	cpu_elf_name
	/* See also feat_v6_fixup() for HWCAP_TLS */
	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP|HWCAP_JAVA|HWCAP_TLS
	.long	cpu_v6_name
	.long	v6_processor_functions
	.long	v6wbi_tlb_fns
	.long	v6_user_fns
	.long	v6_cache_fns
	.size	__v6_proc_info, . - __v6_proc_info