1/*
2 *  linux/arch/arm/mm/proc-sa1100.S
3 *
4 *  Copyright (C) 1997-2002 Russell King
5 *  hacked for non-paged-MM by Hyok S. Choi, 2003.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 *  MMU functions for SA110
12 *
13 *  These are the low level assembler for performing cache and TLB
14 *  functions on the StrongARM-1100 and StrongARM-1110.
15 *
16 *  Note that SA1100 and SA1110 share everything but their name and CPU ID.
17 *
18 *  12-jun-2000, Erik Mouw (J.A.K.Mouw@its.tudelft.nl):
19 *    Flush the read buffer at context switches
20 */
21#include <linux/linkage.h>
22#include <linux/init.h>
23#include <asm/assembler.h>
24#include <asm/asm-offsets.h>
25#include <asm/elf.h>
26#include <asm/hardware.h>
27#include <asm/pgtable-hwdef.h>
28#include <asm/pgtable.h>
29
30#include "proc-macros.S"
31
32/*
33 * the cache line size of the I and D cache
34 */
35#define DCACHELINESIZE	32
36
37	__INIT
38
39/*
40 * cpu_sa1100_proc_init()
41 */
42ENTRY(cpu_sa1100_proc_init)
43	mov	r0, #0
44	mcr	p15, 0, r0, c15, c1, 2		@ Enable clock switching
45	mcr	p15, 0, r0, c9, c0, 5		@ Allow read-buffer operations from userland
46	mov	pc, lr
47
48	.previous
49
50/*
51 * cpu_sa1100_proc_fin()
52 *
53 * Prepare the CPU for reset:
54 *  - Disable interrupts
55 *  - Clean and turn off caches.
56 */
57ENTRY(cpu_sa1100_proc_fin)
58	stmfd	sp!, {lr}
59	mov	ip, #PSR_F_BIT | PSR_I_BIT | SVC_MODE
60	msr	cpsr_c, ip
61	bl	v4wb_flush_kern_cache_all
62	mcr	p15, 0, ip, c15, c2, 2		@ Disable clock switching
63	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
64	bic	r0, r0, #0x1000			@ ...i............
65	bic	r0, r0, #0x000e			@ ............wca.
66	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
67	ldmfd	sp!, {pc}
68
69/*
70 * cpu_sa1100_reset(loc)
71 *
72 * Perform a soft reset of the system.  Put the CPU into the
73 * same state as it would be if it had been reset, and branch
74 * to what would be the reset vector.
75 *
76 * loc: location to jump to for soft reset
77 */
78	.align	5
79ENTRY(cpu_sa1100_reset)
80	mov	ip, #0
81	mcr	p15, 0, ip, c7, c7, 0		@ invalidate I,D caches
82	mcr	p15, 0, ip, c7, c10, 4		@ drain WB
83#ifdef CONFIG_MMU
84	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
85#endif
86	mrc	p15, 0, ip, c1, c0, 0		@ ctrl register
87	bic	ip, ip, #0x000f			@ ............wcam
88	bic	ip, ip, #0x1100			@ ...i...s........
89	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
90	mov	pc, r0
91
92/*
93 * cpu_sa1100_do_idle(type)
94 *
95 * Cause the processor to idle
96 *
97 * type: call type:
98 *   0 = slow idle
99 *   1 = fast idle
100 *   2 = switch to slow processor clock
101 *   3 = switch to fast processor clock
102 */
103	.align	5
104ENTRY(cpu_sa1100_do_idle)
105	mov	r0, r0				@ 4 nop padding
106	mov	r0, r0
107	mov	r0, r0
108	mov	r0, r0				@ 4 nop padding
109	mov	r0, r0
110	mov	r0, r0
111	mov	r0, #0
112	ldr	r1, =UNCACHEABLE_ADDR		@ ptr to uncacheable address
113	@ --- aligned to a cache line
114	mcr	p15, 0, r0, c15, c2, 2		@ disable clock switching
115	ldr	r1, [r1, #0]			@ force switch to MCLK
116	mcr	p15, 0, r0, c15, c8, 2		@ wait for interrupt
117	mov	r0, r0				@ safety
118	mcr	p15, 0, r0, c15, c1, 2		@ enable clock switching
119	mov	pc, lr
120
121/* ================================= CACHE ================================ */
122
123/*
124 * cpu_sa1100_dcache_clean_area(addr,sz)
125 *
126 * Clean the specified entry of any caches such that the MMU
127 * translation fetches will obtain correct data.
128 *
129 * addr: cache-unaligned virtual address
130 */
131	.align	5
132ENTRY(cpu_sa1100_dcache_clean_area)
1331:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
134	add	r0, r0, #DCACHELINESIZE
135	subs	r1, r1, #DCACHELINESIZE
136	bhi	1b
137	mov	pc, lr
138
139/* =============================== PageTable ============================== */
140
141/*
142 * cpu_sa1100_switch_mm(pgd)
143 *
144 * Set the translation base pointer to be as described by pgd.
145 *
146 * pgd: new page tables
147 */
148	.align	5
149ENTRY(cpu_sa1100_switch_mm)
150#ifdef CONFIG_MMU
151	str	lr, [sp, #-4]!
152	bl	v4wb_flush_kern_cache_all	@ clears IP
153	mcr	p15, 0, ip, c9, c0, 0		@ invalidate RB
154	mcr	p15, 0, r0, c2, c0, 0		@ load page table pointer
155	mcr	p15, 0, ip, c8, c7, 0		@ invalidate I & D TLBs
156	ldr	pc, [sp], #4
157#else
158	mov	pc, lr
159#endif
160
161/*
162 * cpu_sa1100_set_pte_ext(ptep, pte, ext)
163 *
164 * Set a PTE and flush it out
165 */
166	.align	5
167ENTRY(cpu_sa1100_set_pte_ext)
168#ifdef CONFIG_MMU
169	str	r1, [r0], #-2048		@ linux version
170
171	eor	r1, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
172
173	bic	r2, r1, #PTE_SMALL_AP_MASK
174	bic	r2, r2, #PTE_TYPE_MASK
175	orr	r2, r2, #PTE_TYPE_SMALL
176
177	tst	r1, #L_PTE_USER			@ User?
178	orrne	r2, r2, #PTE_SMALL_AP_URO_SRW
179
180	tst	r1, #L_PTE_WRITE | L_PTE_DIRTY	@ Write and Dirty?
181	orreq	r2, r2, #PTE_SMALL_AP_UNO_SRW
182
183	tst	r1, #L_PTE_PRESENT | L_PTE_YOUNG	@ Present and Young?
184	movne	r2, #0
185
186	str	r2, [r0]			@ hardware version
187	mov	r0, r0
188	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
189	mcr	p15, 0, r0, c7, c10, 4		@ drain WB
190#endif
191	mov	pc, lr
192
193	__INIT
194
195	.type	__sa1100_setup, #function
196__sa1100_setup:
197	mov	r0, #0
198	mcr	p15, 0, r0, c7, c7		@ invalidate I,D caches on v4
199	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer on v4
200#ifdef CONFIG_MMU
201	mcr	p15, 0, r0, c8, c7		@ invalidate I,D TLBs on v4
202#endif
203	adr	r5, sa1100_crval
204	ldmia	r5, {r5, r6}
205	mrc	p15, 0, r0, c1, c0		@ get control register v4
206	bic	r0, r0, r5
207	orr	r0, r0, r6
208	mov	pc, lr
209	.size	__sa1100_setup, . - __sa1100_setup
210
211	/*
212	 *  R
213	 * .RVI ZFRS BLDP WCAM
214	 * ..11 0001 ..11 1101
215	 *
216	 */
217	.type	sa1100_crval, #object
218sa1100_crval:
219	crval	clear=0x00003f3f, mmuset=0x0000313d, ucset=0x00001130
220
221	__INITDATA
222
223/*
224 * Purpose : Function pointers used to access above functions - all calls
225 *	     come through these
226 */
227
228/*
229 * SA1100 and SA1110 share the same function calls
230 */
231	.type	sa1100_processor_functions, #object
232ENTRY(sa1100_processor_functions)
233	.word	v4_early_abort
234	.word	cpu_sa1100_proc_init
235	.word	cpu_sa1100_proc_fin
236	.word	cpu_sa1100_reset
237	.word	cpu_sa1100_do_idle
238	.word	cpu_sa1100_dcache_clean_area
239	.word	cpu_sa1100_switch_mm
240	.word	cpu_sa1100_set_pte_ext
241	.size	sa1100_processor_functions, . - sa1100_processor_functions
242
243	.section ".rodata"
244
245	.type	cpu_arch_name, #object
246cpu_arch_name:
247	.asciz	"armv4"
248	.size	cpu_arch_name, . - cpu_arch_name
249
250	.type	cpu_elf_name, #object
251cpu_elf_name:
252	.asciz	"v4"
253	.size	cpu_elf_name, . - cpu_elf_name
254
255	.type	cpu_sa1100_name, #object
256cpu_sa1100_name:
257	.asciz	"StrongARM-1100"
258	.size	cpu_sa1100_name, . - cpu_sa1100_name
259
260	.type	cpu_sa1110_name, #object
261cpu_sa1110_name:
262	.asciz	"StrongARM-1110"
263	.size	cpu_sa1110_name, . - cpu_sa1110_name
264
265	.align
266
267	.section ".proc.info.init", #alloc, #execinstr
268
269	.type	__sa1100_proc_info,#object
270__sa1100_proc_info:
271	.long	0x4401a110
272	.long	0xfffffff0
273	.long   PMD_TYPE_SECT | \
274		PMD_SECT_BUFFERABLE | \
275		PMD_SECT_CACHEABLE | \
276		PMD_SECT_AP_WRITE | \
277		PMD_SECT_AP_READ
278	.long   PMD_TYPE_SECT | \
279		PMD_SECT_AP_WRITE | \
280		PMD_SECT_AP_READ
281	b	__sa1100_setup
282	.long	cpu_arch_name
283	.long	cpu_elf_name
284	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_26BIT | HWCAP_FAST_MULT
285	.long	cpu_sa1100_name
286	.long	sa1100_processor_functions
287	.long	v4wb_tlb_fns
288	.long	v4_mc_user_fns
289	.long	v4wb_cache_fns
290	.size	__sa1100_proc_info, . - __sa1100_proc_info
291
292	.type	__sa1110_proc_info,#object
293__sa1110_proc_info:
294	.long	0x6901b110
295	.long	0xfffffff0
296	.long   PMD_TYPE_SECT | \
297		PMD_SECT_BUFFERABLE | \
298		PMD_SECT_CACHEABLE | \
299		PMD_SECT_AP_WRITE | \
300		PMD_SECT_AP_READ
301	.long   PMD_TYPE_SECT | \
302		PMD_SECT_AP_WRITE | \
303		PMD_SECT_AP_READ
304	b	__sa1100_setup
305	.long	cpu_arch_name
306	.long	cpu_elf_name
307	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_26BIT | HWCAP_FAST_MULT
308	.long	cpu_sa1110_name
309	.long	sa1100_processor_functions
310	.long	v4wb_tlb_fns
311	.long	v4_mc_user_fns
312	.long	v4wb_cache_fns
313	.size	__sa1110_proc_info, . - __sa1110_proc_info
314