xref: /openbmc/linux/arch/arm/mm/proc-v7.S (revision 78c99ba1) 
1/*
2 *  linux/arch/arm/mm/proc-v7.S
3 *
4 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 *  This is the "shell" of the ARMv7 processor support.
11 */
12#include <linux/init.h>
13#include <linux/linkage.h>
14#include <asm/assembler.h>
15#include <asm/asm-offsets.h>
16#include <asm/hwcap.h>
17#include <asm/pgtable-hwdef.h>
18#include <asm/pgtable.h>
19
20#include "proc-macros.S"
21
22#define TTB_C		(1 << 0)
23#define TTB_S		(1 << 1)
24#define TTB_RGN_NC	(0 << 3)
25#define TTB_RGN_OC_WBWA	(1 << 3)
26#define TTB_RGN_OC_WT	(2 << 3)
27#define TTB_RGN_OC_WB	(3 << 3)
28
29#ifndef CONFIG_SMP
30#define TTB_FLAGS	TTB_C|TTB_RGN_OC_WB		@ mark PTWs cacheable, outer WB
31#else
32#define TTB_FLAGS	TTB_C|TTB_S|TTB_RGN_OC_WBWA	@ mark PTWs cacheable and shared, outer WBWA
33#endif
34
35ENTRY(cpu_v7_proc_init)
36	mov	pc, lr
37ENDPROC(cpu_v7_proc_init)
38
39ENTRY(cpu_v7_proc_fin)
40	mov	pc, lr
41ENDPROC(cpu_v7_proc_fin)
42
43/*
44 *	cpu_v7_reset(loc)
45 *
46 *	Perform a soft reset of the system.  Put the CPU into the
47 *	same state as it would be if it had been reset, and branch
48 *	to what would be the reset vector.
49 *
50 *	- loc   - location to jump to for soft reset
51 *
52 *	It is assumed that:
53 */
54	.align	5
55ENTRY(cpu_v7_reset)
56	mov	pc, r0
57ENDPROC(cpu_v7_reset)
58
59/*
60 *	cpu_v7_do_idle()
61 *
62 *	Idle the processor (eg, wait for interrupt).
63 *
64 *	IRQs are already disabled.
65 */
66ENTRY(cpu_v7_do_idle)
67	dsb					@ WFI may enter a low-power mode
68	wfi
69	mov	pc, lr
70ENDPROC(cpu_v7_do_idle)
71
72ENTRY(cpu_v7_dcache_clean_area)
73#ifndef TLB_CAN_READ_FROM_L1_CACHE
74	dcache_line_size r2, r3
751:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
76	add	r0, r0, r2
77	subs	r1, r1, r2
78	bhi	1b
79	dsb
80#endif
81	mov	pc, lr
82ENDPROC(cpu_v7_dcache_clean_area)
83
84/*
85 *	cpu_v7_switch_mm(pgd_phys, tsk)
86 *
87 *	Set the translation table base pointer to be pgd_phys
88 *
89 *	- pgd_phys - physical address of new TTB
90 *
91 *	It is assumed that:
92 *	- we are not using split page tables
93 */
94ENTRY(cpu_v7_switch_mm)
95#ifdef CONFIG_MMU
96	mov	r2, #0
97	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
98	orr	r0, r0, #TTB_FLAGS
99#ifdef CONFIG_ARM_ERRATA_430973
100	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB
101#endif
102	mcr	p15, 0, r2, c13, c0, 1		@ set reserved context ID
103	isb
1041:	mcr	p15, 0, r0, c2, c0, 0		@ set TTB 0
105	isb
106	mcr	p15, 0, r1, c13, c0, 1		@ set context ID
107	isb
108#endif
109	mov	pc, lr
110ENDPROC(cpu_v7_switch_mm)
111
112/*
113 *	cpu_v7_set_pte_ext(ptep, pte)
114 *
115 *	Set a level 2 translation table entry.
116 *
117 *	- ptep  - pointer to level 2 translation table entry
118 *		  (hardware version is stored at -1024 bytes)
119 *	- pte   - PTE value to store
120 *	- ext	- value for extended PTE bits
121 */
122ENTRY(cpu_v7_set_pte_ext)
123#ifdef CONFIG_MMU
124	str	r1, [r0], #-2048		@ linux version
125
126	bic	r3, r1, #0x000003f0
127	bic	r3, r3, #PTE_TYPE_MASK
128	orr	r3, r3, r2
129	orr	r3, r3, #PTE_EXT_AP0 | 2
130
131	tst	r1, #1 << 4
132	orrne	r3, r3, #PTE_EXT_TEX(1)
133
134	tst	r1, #L_PTE_WRITE
135	tstne	r1, #L_PTE_DIRTY
136	orreq	r3, r3, #PTE_EXT_APX
137
138	tst	r1, #L_PTE_USER
139	orrne	r3, r3, #PTE_EXT_AP1
140	tstne	r3, #PTE_EXT_APX
141	bicne	r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
142
143	tst	r1, #L_PTE_EXEC
144	orreq	r3, r3, #PTE_EXT_XN
145
146	tst	r1, #L_PTE_YOUNG
147	tstne	r1, #L_PTE_PRESENT
148	moveq	r3, #0
149
150	str	r3, [r0]
151	mcr	p15, 0, r0, c7, c10, 1		@ flush_pte
152#endif
153	mov	pc, lr
154ENDPROC(cpu_v7_set_pte_ext)
155
156cpu_v7_name:
157	.ascii	"ARMv7 Processor"
158	.align
159
160	__INIT
161
162/*
163 *	__v7_setup
164 *
165 *	Initialise TLB, Caches, and MMU state ready to switch the MMU
166 *	on.  Return in r0 the new CP15 C1 control register setting.
167 *
168 *	We automatically detect if we have a Harvard cache, and use the
169 *	Harvard cache control instructions insead of the unified cache
170 *	control instructions.
171 *
172 *	This should be able to cover all ARMv7 cores.
173 *
174 *	It is assumed that:
175 *	- cache type register is implemented
176 */
177__v7_setup:
178#ifdef CONFIG_SMP
179	mrc	p15, 0, r0, c1, c0, 1		@ Enable SMP/nAMP mode
180	orr	r0, r0, #(0x1 << 6)
181	mcr	p15, 0, r0, c1, c0, 1
182#endif
183	adr	r12, __v7_setup_stack		@ the local stack
184	stmia	r12, {r0-r5, r7, r9, r11, lr}
185	bl	v7_flush_dcache_all
186	ldmia	r12, {r0-r5, r7, r9, r11, lr}
187
188	mrc	p15, 0, r0, c0, c0, 0		@ read main ID register
189	and	r10, r0, #0xff000000		@ ARM?
190	teq	r10, #0x41000000
191	bne	2f
192	and	r5, r0, #0x00f00000		@ variant
193	and	r6, r0, #0x0000000f		@ revision
194	orr	r0, r6, r5, lsr #20-4		@ combine variant and revision
195
196#ifdef CONFIG_ARM_ERRATA_430973
197	teq	r5, #0x00100000			@ only present in r1p*
198	mrceq	p15, 0, r10, c1, c0, 1		@ read aux control register
199	orreq	r10, r10, #(1 << 6)		@ set IBE to 1
200	mcreq	p15, 0, r10, c1, c0, 1		@ write aux control register
201#endif
202#ifdef CONFIG_ARM_ERRATA_458693
203	teq	r0, #0x20			@ only present in r2p0
204	mrceq	p15, 0, r10, c1, c0, 1		@ read aux control register
205	orreq	r10, r10, #(1 << 5)		@ set L1NEON to 1
206	orreq	r10, r10, #(1 << 9)		@ set PLDNOP to 1
207	mcreq	p15, 0, r10, c1, c0, 1		@ write aux control register
208#endif
209#ifdef CONFIG_ARM_ERRATA_460075
210	teq	r0, #0x20			@ only present in r2p0
211	mrceq	p15, 1, r10, c9, c0, 2		@ read L2 cache aux ctrl register
212	tsteq	r10, #1 << 22
213	orreq	r10, r10, #(1 << 22)		@ set the Write Allocate disable bit
214	mcreq	p15, 1, r10, c9, c0, 2		@ write the L2 cache aux ctrl register
215#endif
216
2172:	mov	r10, #0
218#ifdef HARVARD_CACHE
219	mcr	p15, 0, r10, c7, c5, 0		@ I+BTB cache invalidate
220#endif
221	dsb
222#ifdef CONFIG_MMU
223	mcr	p15, 0, r10, c8, c7, 0		@ invalidate I + D TLBs
224	mcr	p15, 0, r10, c2, c0, 2		@ TTB control register
225	orr	r4, r4, #TTB_FLAGS
226	mcr	p15, 0, r4, c2, c0, 1		@ load TTB1
227	mov	r10, #0x1f			@ domains 0, 1 = manager
228	mcr	p15, 0, r10, c3, c0, 0		@ load domain access register
229#endif
230	ldr	r5, =0xff0aa1a8
231	ldr	r6, =0x40e040e0
232	mcr	p15, 0, r5, c10, c2, 0		@ write PRRR
233	mcr	p15, 0, r6, c10, c2, 1		@ write NMRR
234	adr	r5, v7_crval
235	ldmia	r5, {r5, r6}
236   	mrc	p15, 0, r0, c1, c0, 0		@ read control register
237	bic	r0, r0, r5			@ clear bits them
238	orr	r0, r0, r6			@ set them
239	mov	pc, lr				@ return to head.S:__ret
240ENDPROC(__v7_setup)
241
242	/*   AT
243	 *  TFR   EV X F   I D LR
244	 * .EEE ..EE PUI. .T.T 4RVI ZFRS BLDP WCAM
245	 * rxxx rrxx xxx0 0101 xxxx xxxx x111 xxxx < forced
246	 *    1    0 110       0011 1.00 .111 1101 < we want
247	 */
248	.type	v7_crval, #object
249v7_crval:
250	crval	clear=0x0120c302, mmuset=0x10c0387d, ucset=0x00c0187c
251
252__v7_setup_stack:
253	.space	4 * 11				@ 11 registers
254
255	.type	v7_processor_functions, #object
256ENTRY(v7_processor_functions)
257	.word	v7_early_abort
258	.word	pabort_ifar
259	.word	cpu_v7_proc_init
260	.word	cpu_v7_proc_fin
261	.word	cpu_v7_reset
262	.word	cpu_v7_do_idle
263	.word	cpu_v7_dcache_clean_area
264	.word	cpu_v7_switch_mm
265	.word	cpu_v7_set_pte_ext
266	.size	v7_processor_functions, . - v7_processor_functions
267
268	.type	cpu_arch_name, #object
269cpu_arch_name:
270	.asciz	"armv7"
271	.size	cpu_arch_name, . - cpu_arch_name
272
273	.type	cpu_elf_name, #object
274cpu_elf_name:
275	.asciz	"v7"
276	.size	cpu_elf_name, . - cpu_elf_name
277	.align
278
279	.section ".proc.info.init", #alloc, #execinstr
280
281	/*
282	 * Match any ARMv7 processor core.
283	 */
284	.type	__v7_proc_info, #object
285__v7_proc_info:
286	.long	0x000f0000		@ Required ID value
287	.long	0x000f0000		@ Mask for ID
288	.long   PMD_TYPE_SECT | \
289		PMD_SECT_BUFFERABLE | \
290		PMD_SECT_CACHEABLE | \
291		PMD_SECT_AP_WRITE | \
292		PMD_SECT_AP_READ
293	.long   PMD_TYPE_SECT | \
294		PMD_SECT_XN | \
295		PMD_SECT_AP_WRITE | \
296		PMD_SECT_AP_READ
297	b	__v7_setup
298	.long	cpu_arch_name
299	.long	cpu_elf_name
300	.long	HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_EDSP
301	.long	cpu_v7_name
302	.long	v7_processor_functions
303	.long	v7wbi_tlb_fns
304	.long	v6_user_fns
305	.long	v7_cache_fns
306	.size	__v7_proc_info, . - __v7_proc_info
307