| blob | f9fca524c57afa920431d5cd20a41959928fd21e |
1 /*
2 * linux/arch/arm26/mm/proc-arm2,3.S
3 *
4 * Copyright (C) 1997-1999 Russell King
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 * MMU functions for ARM2,3
11 *
12 * These are the low level assembler for performing cache
13 * and memory functions on ARM2, ARM250 and ARM3 processors.
14 */
15 #include <linux/linkage.h>
16 #include <asm/assembler.h>
17 #include <asm/asm-offsets.h>
18 #include <asm/procinfo.h>
19 #include <asm/ptrace.h>
21 /*
22 * MEMC workhorse code. It's both a horse which things it's a pig.
23 */
24 /*
25 * Function: cpu_memc_update_entry(pgd_t *pgd, unsigned long phys_pte, unsigned long addr)
26 * Params : pgd Page tables/MEMC mapping
27 * : phys_pte physical address, or PTE
28 * : addr virtual address
29 */
30 ENTRY(cpu_memc_update_entry)
31 tst r1, #PAGE_PRESENT @ is the page present
32 orreq r1, r1, #PAGE_OLD | PAGE_CLEAN
33 moveq r2, #0x01f00000
34 mov r3, r1, lsr #13 @ convert to physical page nr
35 and r3, r3, #0x3fc
36 adr ip, memc_phys_table_32
37 ldr r3, [ip, r3]
38 tst r1, #PAGE_OLD | PAGE_NOT_USER
39 biceq r3, r3, #0x200
40 tsteq r1, #PAGE_READONLY | PAGE_CLEAN
41 biceq r3, r3, #0x300
42 mov r2, r2, lsr #15 @ virtual -> nr
43 orr r3, r3, r2, lsl #15
44 and r2, r2, #0x300
45 orr r3, r3, r2, lsl #2
46 and r2, r3, #255
47 sub r0, r0, #256 * 4
48 str r3, [r0, r2, lsl #2]
49 strb r3, [r3]
50 movs pc, lr
51 /*
52 * Params : r0 = preserved
53 * : r1 = memc table base (preserved)
54 * : r2 = page table entry
55 * : r3 = preserved
56 * : r4 = unused
57 * : r5 = memc physical address translation table
58 * : ip = virtual address (preserved)
59 */
60 update_pte:
61 mov r4, r2, lsr #13
62 and r4, r4, #0x3fc
63 ldr r4, [r5, r4] @ covert to MEMC page
65 tst r2, #PAGE_OLD | PAGE_NOT_USER @ check for MEMC read
66 biceq r4, r4, #0x200
67 tsteq r2, #PAGE_READONLY | PAGE_CLEAN @ check for MEMC write
68 biceq r4, r4, #0x300
70 orr r4, r4, ip
71 and r2, ip, #0x01800000
72 orr r4, r4, r2, lsr #13
74 and r2, r4, #255
75 str r4, [r1, r2, lsl #2]
76 movs pc, lr
78 /*
79 * Params : r0 = preserved
80 * : r1 = memc table base (preserved)
81 * : r2 = page table base
82 * : r3 = preserved
83 * : r4 = unused
84 * : r5 = memc physical address translation table
85 * : ip = virtual address (updated)
86 */
87 update_pte_table:
88 stmfd sp!, {r0, lr}
89 bic r0, r2, #3
90 1: ldr r2, [r0], #4 @ get entry
91 tst r2, #PAGE_PRESENT @ page present
92 blne update_pte @ process pte
93 add ip, ip, #32768 @ increment virt addr
94 ldr r2, [r0], #4 @ get entry
95 tst r2, #PAGE_PRESENT @ page present
96 blne update_pte @ process pte
97 add ip, ip, #32768 @ increment virt addr
98 ldr r2, [r0], #4 @ get entry
99 tst r2, #PAGE_PRESENT @ page present
100 blne update_pte @ process pte
101 add ip, ip, #32768 @ increment virt addr
102 ldr r2, [r0], #4 @ get entry
103 tst r2, #PAGE_PRESENT @ page present
104 blne update_pte @ process pte
105 add ip, ip, #32768 @ increment virt addr
106 tst ip, #32768 * 31 @ finished?
107 bne 1b
108 ldmfd sp!, {r0, pc}^
110 /*
111 * Function: cpu_memc_update_all(pgd_t *pgd)
112 * Params : pgd Page tables/MEMC mapping
113 * Notes : this is optimised for 32k pages
114 */
115 ENTRY(cpu_memc_update_all)
116 stmfd sp!, {r4, r5, lr}
117 bl clear_tables
118 sub r1, r0, #256 * 4 @ start of MEMC tables
119 adr r5, memc_phys_table_32 @ Convert to logical page number
120 mov ip, #0 @ virtual address
121 1: ldmia r0!, {r2, r3} @ load two pgd entries
122 tst r2, #PAGE_PRESENT @ is pgd entry present?
123 addeq ip, ip, #1048576 @FIXME - PAGE_PRESENT is for PTEs technically...
124 blne update_pte_table
125 mov r2, r3
126 tst r2, #PAGE_PRESENT @ is pgd entry present?
127 addeq ip, ip, #1048576
128 blne update_pte_table
129 teq ip, #32 * 1048576
130 bne 1b
131 ldmfd sp!, {r4, r5, pc}^
133 /*
134 * Build the table to map from physical page number to memc page number
135 */
136 .type memc_phys_table_32, #object
137 memc_phys_table_32:
138 .irp b7, 0x00, 0x80
139 .irp b6, 0x00, 0x02
140 .irp b5, 0x00, 0x04
141 .irp b4, 0x00, 0x01
143 .irp b3, 0x00, 0x40
144 .irp b2, 0x00, 0x20
145 .irp b1, 0x00, 0x10
146 .irp b0, 0x00, 0x08
147 .long 0x03800300 + \b7 + \b6 + \b5 + \b4 + \b3 + \b2 + \b1 + \b0
148 .endr
149 .endr
150 .endr
151 .endr
153 .endr
154 .endr
155 .endr
156 .endr
157 .size memc_phys_table_32, . - memc_phys_table_32
159 /*
160 * helper for cpu_memc_update_all, this clears out all
161 * mappings, setting them close to the top of memory,
162 * and inaccessible (0x01f00000).
163 * Params : r0 = page table pointer
164 */
165 clear_tables: ldr r1, _arm3_set_pgd - 4
166 ldr r2, [r1]
167 sub r1, r0, #256 * 4 @ start of MEMC tables
168 add r2, r1, r2, lsl #2 @ end of tables
169 mov r3, #0x03f00000 @ Default mapping (null mapping)
170 orr r3, r3, #0x00000f00
171 orr r4, r3, #1
172 orr r5, r3, #2
173 orr ip, r3, #3
174 1: stmia r1!, {r3, r4, r5, ip}
175 add r3, r3, #4
176 add r4, r4, #4
177 add r5, r5, #4
178 add ip, ip, #4
179 stmia r1!, {r3, r4, r5, ip}
180 add r3, r3, #4
181 add r4, r4, #4
182 add r5, r5, #4
183 add ip, ip, #4
184 teq r1, r2
185 bne 1b
186 mov pc, lr
188 /*
189 * Function: *_set_pgd(pgd_t *pgd)
190 * Params : pgd New page tables/MEMC mapping
191 * Purpose : update MEMC hardware with new mapping
192 */
193 .word page_nr @ extern - declared in mm-memc.c
194 _arm3_set_pgd: mcr p15, 0, r1, c1, c0, 0 @ flush cache
195 _arm2_set_pgd: stmfd sp!, {lr}
196 ldr r1, _arm3_set_pgd - 4
197 ldr r2, [r1]
198 sub r0, r0, #256 * 4 @ start of MEMC tables
199 add r1, r0, r2, lsl #2 @ end of tables
200 1: ldmia r0!, {r2, r3, ip, lr}
201 strb r2, [r2]
202 strb r3, [r3]
203 strb ip, [ip]
204 strb lr, [lr]
205 ldmia r0!, {r2, r3, ip, lr}
206 strb r2, [r2]
207 strb r3, [r3]
208 strb ip, [ip]
209 strb lr, [lr]
210 teq r0, r1
211 bne 1b
212 ldmfd sp!, {pc}^
214 /*
215 * Function: *_proc_init (void)
216 * Purpose : Initialise the cache control registers
217 */
218 _arm3_proc_init:
219 mov r0, #0x001f0000
220 orr r0, r0, #0x0000ff00
221 orr r0, r0, #0x000000ff
222 mcr p15, 0, r0, c3, c0 @ ARM3 Cacheable
223 mcr p15, 0, r0, c4, c0 @ ARM3 Updateable
224 mov r0, #0
225 mcr p15, 0, r0, c5, c0 @ ARM3 Disruptive
226 mcr p15, 0, r0, c1, c0 @ ARM3 Flush
227 mov r0, #3
228 mcr p15, 0, r0, c2, c0 @ ARM3 Control
229 _arm2_proc_init:
230 movs pc, lr
232 /*
233 * Function: *_proc_fin (void)
234 * Purpose : Finalise processor (disable caches)
235 */
236 _arm3_proc_fin: mov r0, #2
237 mcr p15, 0, r0, c2, c0
238 _arm2_proc_fin: orrs pc, lr, #PSR_I_BIT|PSR_F_BIT
240 /*
241 * Function: *_xchg_1 (int new, volatile void *ptr)
242 * Params : new New value to store at...
243 * : ptr pointer to byte-wide location
244 * Purpose : Performs an exchange operation
245 * Returns : Original byte data at 'ptr'
246 */
247 _arm2_xchg_1: mov r2, pc
248 orr r2, r2, #PSR_I_BIT
249 teqp r2, #0
250 ldrb r2, [r1]
251 strb r0, [r1]
252 mov r0, r2
253 movs pc, lr
255 _arm3_xchg_1: swpb r0, r0, [r1]
256 movs pc, lr
258 /*
259 * Function: *_xchg_4 (int new, volatile void *ptr)
260 * Params : new New value to store at...
261 * : ptr pointer to word-wide location
262 * Purpose : Performs an exchange operation
263 * Returns : Original word data at 'ptr'
264 */
265 _arm2_xchg_4: mov r2, pc
266 orr r2, r2, #PSR_I_BIT
267 teqp r2, #0
268 ldr r2, [r1]
269 str r0, [r1]
270 mov r0, r2
271 movs pc, lr
273 _arm3_xchg_4: swp r0, r0, [r1]
274 movs pc, lr
276 _arm2_3_check_bugs:
277 bics pc, lr, #PSR_F_BIT @ Clear FIQ disable bit
279 armvlsi_name: .asciz "ARM/VLSI"
280 _arm2_name: .asciz "ARM 2"
281 _arm250_name: .asciz "ARM 250"
282 _arm3_name: .asciz "ARM 3"
284 .section ".init.text", #alloc, #execinstr
285 /*
286 * Purpose : Function pointers used to access above functions - all calls
287 * come through these
288 */
289 .globl arm2_processor_functions
290 arm2_processor_functions:
291 .word _arm2_3_check_bugs
292 .word _arm2_proc_init
293 .word _arm2_proc_fin
294 .word _arm2_set_pgd
295 .word _arm2_xchg_1
296 .word _arm2_xchg_4
298 cpu_arm2_info:
299 .long armvlsi_name
300 .long _arm2_name
302 .globl arm250_processor_functions
303 arm250_processor_functions:
304 .word _arm2_3_check_bugs
305 .word _arm2_proc_init
306 .word _arm2_proc_fin
307 .word _arm2_set_pgd
308 .word _arm3_xchg_1
309 .word _arm3_xchg_4
311 cpu_arm250_info:
312 .long armvlsi_name
313 .long _arm250_name
315 .globl arm3_processor_functions
316 arm3_processor_functions:
317 .word _arm2_3_check_bugs
318 .word _arm3_proc_init
319 .word _arm3_proc_fin
320 .word _arm3_set_pgd
321 .word _arm3_xchg_1
322 .word _arm3_xchg_4
324 cpu_arm3_info:
325 .long armvlsi_name
326 .long _arm3_name
328 arm2_arch_name: .asciz "armv1"
329 arm3_arch_name: .asciz "armv2"
330 arm2_elf_name: .asciz "v1"
331 arm3_elf_name: .asciz "v2"
332 .align
334 .section ".proc.info", #alloc, #execinstr
336 .long 0x41560200
337 .long 0xfffffff0
338 .long arm2_arch_name
339 .long arm2_elf_name
340 .long 0
341 .long cpu_arm2_info
342 .long arm2_processor_functions
344 .long 0x41560250
345 .long 0xfffffff0
346 .long arm3_arch_name
347 .long arm3_elf_name
348 .long 0
349 .long cpu_arm250_info
350 .long arm250_processor_functions
352 .long 0x41560300
353 .long 0xfffffff0
354 .long arm3_arch_name
355 .long arm3_elf_name
356 .long 0
357 .long cpu_arm3_info
358 .long arm3_processor_functions