1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * linux/arch/arm/mm/arm946.S: utility functions for ARM946E-S
4 *
5 * Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com)
6 *
7 * (Many of cache codes are from proc-arm926.S)
8 */
9#include <linux/linkage.h>
10#include <linux/init.h>
11#include <linux/pgtable.h>
12#include <asm/assembler.h>
13#include <asm/hwcap.h>
14#include <asm/pgtable-hwdef.h>
15#include <asm/ptrace.h>
16#include "proc-macros.S"
17
18/*
19 * ARM946E-S is synthesizable to have 0KB to 1MB sized D-Cache,
20 * comprising 256 lines of 32 bytes (8 words).
21 */
22#define CACHE_DSIZE (CONFIG_CPU_DCACHE_SIZE) /* typically 8KB. */
23#define CACHE_DLINESIZE 32 /* fixed */
24#define CACHE_DSEGMENTS 4 /* fixed */
25#define CACHE_DENTRIES (CACHE_DSIZE / CACHE_DSEGMENTS / CACHE_DLINESIZE)
26#define CACHE_DLIMIT (CACHE_DSIZE * 4) /* benchmark needed */
27
28 .text
29/*
30 * cpu_arm946_proc_init()
31 * cpu_arm946_switch_mm()
32 *
33 * These are not required.
34 */
35ENTRY(cpu_arm946_proc_init)
36ENTRY(cpu_arm946_switch_mm)
37 ret lr
38
39/*
40 * cpu_arm946_proc_fin()
41 */
42ENTRY(cpu_arm946_proc_fin)
43 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
44 bic r0, r0, #0x00001000 @ i-cache
45 bic r0, r0, #0x00000004 @ d-cache
46 mcr p15, 0, r0, c1, c0, 0 @ disable caches
47 ret lr
48
49/*
50 * cpu_arm946_reset(loc)
51 * Params : r0 = address to jump to
52 * Notes : This sets up everything for a reset
53 */
54 .pushsection .idmap.text, "ax"
55ENTRY(cpu_arm946_reset)
56 mov ip, #0
57 mcr p15, 0, ip, c7, c5, 0 @ flush I cache
58 mcr p15, 0, ip, c7, c6, 0 @ flush D cache
59 mcr p15, 0, ip, c7, c10, 4 @ drain WB
60 mrc p15, 0, ip, c1, c0, 0 @ ctrl register
61 bic ip, ip, #0x00000005 @ .............c.p
62 bic ip, ip, #0x00001000 @ i-cache
63 mcr p15, 0, ip, c1, c0, 0 @ ctrl register
64 ret r0
65ENDPROC(cpu_arm946_reset)
66 .popsection
67
68/*
69 * cpu_arm946_do_idle()
70 */
71 .align 5
72ENTRY(cpu_arm946_do_idle)
73 mcr p15, 0, r0, c7, c0, 4 @ Wait for interrupt
74 ret lr
75
76/*
77 * flush_icache_all()
78 *
79 * Unconditionally clean and invalidate the entire icache.
80 */
81ENTRY(arm946_flush_icache_all)
82 mov r0, #0
83 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
84 ret lr
85ENDPROC(arm946_flush_icache_all)
86
87/*
88 * flush_user_cache_all()
89 */
90ENTRY(arm946_flush_user_cache_all)
91 /* FALLTHROUGH */
92
93/*
94 * flush_kern_cache_all()
95 *
96 * Clean and invalidate the entire cache.
97 */
98ENTRY(arm946_flush_kern_cache_all)
99 mov r2, #VM_EXEC
100 mov ip, #0
101__flush_whole_cache:
102#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
103 mcr p15, 0, ip, c7, c6, 0 @ flush D cache
104#else
105 mov r1, #(CACHE_DSEGMENTS - 1) << 29 @ 4 segments
1061: orr r3, r1, #(CACHE_DENTRIES - 1) << 4 @ n entries
1072: mcr p15, 0, r3, c7, c14, 2 @ clean/flush D index
108 subs r3, r3, #1 << 4
109 bcs 2b @ entries n to 0
110 subs r1, r1, #1 << 29
111 bcs 1b @ segments 3 to 0
112#endif
113 tst r2, #VM_EXEC
114 mcrne p15, 0, ip, c7, c5, 0 @ flush I cache
115 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
116 ret lr
117
118/*
119 * flush_user_cache_range(start, end, flags)
120 *
121 * Clean and invalidate a range of cache entries in the
122 * specified address range.
123 *
124 * - start - start address (inclusive)
125 * - end - end address (exclusive)
126 * - flags - vm_flags describing address space
127 * (same as arm926)
128 */
129ENTRY(arm946_flush_user_cache_range)
130 mov ip, #0
131 sub r3, r1, r0 @ calculate total size
132 cmp r3, #CACHE_DLIMIT
133 bhs __flush_whole_cache
134
1351: tst r2, #VM_EXEC
136#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
137 mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
138 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
139 add r0, r0, #CACHE_DLINESIZE
140 mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
141 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
142 add r0, r0, #CACHE_DLINESIZE
143#else
144 mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
145 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
146 add r0, r0, #CACHE_DLINESIZE
147 mcr p15, 0, r0, c7, c14, 1 @ clean and invalidate D entry
148 mcrne p15, 0, r0, c7, c5, 1 @ invalidate I entry
149 add r0, r0, #CACHE_DLINESIZE
150#endif
151 cmp r0, r1
152 blo 1b
153 tst r2, #VM_EXEC
154 mcrne p15, 0, ip, c7, c10, 4 @ drain WB
155 ret lr
156
157/*
158 * coherent_kern_range(start, end)
159 *
160 * Ensure coherency between the Icache and the Dcache in the
161 * region described by start, end. If you have non-snooping
162 * Harvard caches, you need to implement this function.
163 *
164 * - start - virtual start address
165 * - end - virtual end address
166 */
167ENTRY(arm946_coherent_kern_range)
168 /* FALLTHROUGH */
169
170/*
171 * coherent_user_range(start, end)
172 *
173 * Ensure coherency between the Icache and the Dcache in the
174 * region described by start, end. If you have non-snooping
175 * Harvard caches, you need to implement this function.
176 *
177 * - start - virtual start address
178 * - end - virtual end address
179 * (same as arm926)
180 */
181ENTRY(arm946_coherent_user_range)
182 bic r0, r0, #CACHE_DLINESIZE - 1
1831: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
184 mcr p15, 0, r0, c7, c5, 1 @ invalidate I entry
185 add r0, r0, #CACHE_DLINESIZE
186 cmp r0, r1
187 blo 1b
188 mcr p15, 0, r0, c7, c10, 4 @ drain WB
189 mov r0, #0
190 ret lr
191
192/*
193 * flush_kern_dcache_area(void *addr, size_t size)
194 *
195 * Ensure no D cache aliasing occurs, either with itself or
196 * the I cache
197 *
198 * - addr - kernel address
199 * - size - region size
200 * (same as arm926)
201 */
202ENTRY(arm946_flush_kern_dcache_area)
203 add r1, r0, r1
2041: mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
205 add r0, r0, #CACHE_DLINESIZE
206 cmp r0, r1
207 blo 1b
208 mov r0, #0
209 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
210 mcr p15, 0, r0, c7, c10, 4 @ drain WB
211 ret lr
212
213/*
214 * dma_inv_range(start, end)
215 *
216 * Invalidate (discard) the specified virtual address range.
217 * May not write back any entries. If 'start' or 'end'
218 * are not cache line aligned, those lines must be written
219 * back.
220 *
221 * - start - virtual start address
222 * - end - virtual end address
223 * (same as arm926)
224 */
225arm946_dma_inv_range:
226#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
227 tst r0, #CACHE_DLINESIZE - 1
228 mcrne p15, 0, r0, c7, c10, 1 @ clean D entry
229 tst r1, #CACHE_DLINESIZE - 1
230 mcrne p15, 0, r1, c7, c10, 1 @ clean D entry
231#endif
232 bic r0, r0, #CACHE_DLINESIZE - 1
2331: mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
234 add r0, r0, #CACHE_DLINESIZE
235 cmp r0, r1
236 blo 1b
237 mcr p15, 0, r0, c7, c10, 4 @ drain WB
238 ret lr
239
240/*
241 * dma_clean_range(start, end)
242 *
243 * Clean the specified virtual address range.
244 *
245 * - start - virtual start address
246 * - end - virtual end address
247 *
248 * (same as arm926)
249 */
250arm946_dma_clean_range:
251#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
252 bic r0, r0, #CACHE_DLINESIZE - 1
2531: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
254 add r0, r0, #CACHE_DLINESIZE
255 cmp r0, r1
256 blo 1b
257#endif
258 mcr p15, 0, r0, c7, c10, 4 @ drain WB
259 ret lr
260
261/*
262 * dma_flush_range(start, end)
263 *
264 * Clean and invalidate the specified virtual address range.
265 *
266 * - start - virtual start address
267 * - end - virtual end address
268 *
269 * (same as arm926)
270 */
271ENTRY(arm946_dma_flush_range)
272 bic r0, r0, #CACHE_DLINESIZE - 1
2731:
274#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
275 mcr p15, 0, r0, c7, c14, 1 @ clean+invalidate D entry
276#else
277 mcr p15, 0, r0, c7, c6, 1 @ invalidate D entry
278#endif
279 add r0, r0, #CACHE_DLINESIZE
280 cmp r0, r1
281 blo 1b
282 mcr p15, 0, r0, c7, c10, 4 @ drain WB
283 ret lr
284
285/*
286 * dma_map_area(start, size, dir)
287 * - start - kernel virtual start address
288 * - size - size of region
289 * - dir - DMA direction
290 */
291ENTRY(arm946_dma_map_area)
292 add r1, r1, r0
293 cmp r2, #DMA_TO_DEVICE
294 beq arm946_dma_clean_range
295 bcs arm946_dma_inv_range
296 b arm946_dma_flush_range
297ENDPROC(arm946_dma_map_area)
298
299/*
300 * dma_unmap_area(start, size, dir)
301 * - start - kernel virtual start address
302 * - size - size of region
303 * - dir - DMA direction
304 */
305ENTRY(arm946_dma_unmap_area)
306 ret lr
307ENDPROC(arm946_dma_unmap_area)
308
309 .globl arm946_flush_kern_cache_louis
310 .equ arm946_flush_kern_cache_louis, arm946_flush_kern_cache_all
311
312 @ define struct cpu_cache_fns (see <asm/cacheflush.h> and proc-macros.S)
313 define_cache_functions arm946
314
315ENTRY(cpu_arm946_dcache_clean_area)
316#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
3171: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
318 add r0, r0, #CACHE_DLINESIZE
319 subs r1, r1, #CACHE_DLINESIZE
320 bhi 1b
321#endif
322 mcr p15, 0, r0, c7, c10, 4 @ drain WB
323 ret lr
324
325 .type __arm946_setup, #function
326__arm946_setup:
327 mov r0, #0
328 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
329 mcr p15, 0, r0, c7, c6, 0 @ invalidate D cache
330 mcr p15, 0, r0, c7, c10, 4 @ drain WB
331
332 mcr p15, 0, r0, c6, c3, 0 @ disable memory region 3~7
333 mcr p15, 0, r0, c6, c4, 0
334 mcr p15, 0, r0, c6, c5, 0
335 mcr p15, 0, r0, c6, c6, 0
336 mcr p15, 0, r0, c6, c7, 0
337
338 mov r0, #0x0000003F @ base = 0, size = 4GB
339 mcr p15, 0, r0, c6, c0, 0 @ set region 0, default
340
341 ldr r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM
342 ldr r7, =CONFIG_DRAM_SIZE @ size of RAM (must be >= 4KB)
343 pr_val r3, r0, r7, #1
344 mcr p15, 0, r3, c6, c1, 0
345
346 ldr r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH
347 ldr r7, =CONFIG_FLASH_SIZE @ size of FLASH (must be >= 4KB)
348 pr_val r3, r0, r7, #1
349 mcr p15, 0, r3, c6, c2, 0
350
351 mov r0, #0x06
352 mcr p15, 0, r0, c2, c0, 0 @ region 1,2 d-cacheable
353 mcr p15, 0, r0, c2, c0, 1 @ region 1,2 i-cacheable
354#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
355 mov r0, #0x00 @ disable whole write buffer
356#else
357 mov r0, #0x02 @ region 1 write bufferred
358#endif
359 mcr p15, 0, r0, c3, c0, 0
360
361/*
362 * Access Permission Settings for future permission control by PU.
363 *
364 * priv. user
365 * region 0 (whole) rw -- : b0001
366 * region 1 (RAM) rw rw : b0011
367 * region 2 (FLASH) rw r- : b0010
368 * region 3~7 (none) -- -- : b0000
369 */
370 mov r0, #0x00000031
371 orr r0, r0, #0x00000200
372 mcr p15, 0, r0, c5, c0, 2 @ set data access permission
373 mcr p15, 0, r0, c5, c0, 3 @ set inst. access permission
374
375 mrc p15, 0, r0, c1, c0 @ get control register
376 orr r0, r0, #0x00001000 @ I-cache
377 orr r0, r0, #0x00000005 @ MPU/D-cache
378#ifdef CONFIG_CPU_CACHE_ROUND_ROBIN
379 orr r0, r0, #0x00004000 @ .1.. .... .... ....
380#endif
381 ret lr
382
383 .size __arm946_setup, . - __arm946_setup
384
385 __INITDATA
386
387 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
388 define_processor_functions arm946, dabort=nommu_early_abort, pabort=legacy_pabort, nommu=1
389
390 .section ".rodata"
391
392 string cpu_arch_name, "armv5te"
393 string cpu_elf_name, "v5t"
394 string cpu_arm946_name, "ARM946E-S"
395
396 .align
397
398 .section ".proc.info.init", "a"
399 .type __arm946_proc_info,#object
400__arm946_proc_info:
401 .long 0x41009460
402 .long 0xff00fff0
403 .long 0
404 .long 0
405 initfn __arm946_setup, __arm946_proc_info
406 .long cpu_arch_name
407 .long cpu_elf_name
408 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB
409 .long cpu_arm946_name
410 .long arm946_processor_functions
411 .long 0
412 .long 0
413 .long arm946_cache_fns
414 .size __arm946_proc_info, . - __arm946_proc_info
415
416

source code of linux/arch/arm/mm/proc-arm946.S