1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * copy_page, __copy_user_page, __copy_user im
4 *
5 * Copyright (C) 2001 Niibe Yutaka & Kaz Koji
6 * Copyright (C) 2002 Toshinobu Sugioka
7 * Copyright (C) 2006 Paul Mundt
8 */
9 #include <linux/linkage.h>
10 #include <asm/page.h>
11
12 /*
13 * copy_page
14 * @to: P1 address
15 * @from: P1 address
16 *
17 * void copy_page(void *to, void *from)
18 */
19
20 /*
21 * r0, r1, r2, r3, r4, r5, r6, r7 --- scratch
22 * r8 --- from + PAGE_SIZE
23 * r9 --- not used
24 * r10 --- to
25 * r11 --- from
26 */
27 ENTRY(copy_page)
28 mov.l r8,@-r15
29 mov.l r10,@-r15
30 mov.l r11,@-r15
31 mov r4,r10
32 mov r5,r11
33 mov r5,r8
34 mov #(PAGE_SIZE >> 10), r0
35 shll8 r0
36 shll2 r0
37 add r0,r8
38 !
39 1: mov.l @r11+,r0
40 mov.l @r11+,r1
41 mov.l @r11+,r2
42 mov.l @r11+,r3
43 mov.l @r11+,r4
44 mov.l @r11+,r5
45 mov.l @r11+,r6
46 mov.l @r11+,r7
47 #if defined(CONFIG_CPU_SH4)
48 movca.l r0,@r10
49 #else
50 mov.l r0,@r10
51 #endif
52 add #32,r10
53 mov.l r7,@-r10
54 mov.l r6,@-r10
55 mov.l r5,@-r10
56 mov.l r4,@-r10
57 mov.l r3,@-r10
58 mov.l r2,@-r10
59 mov.l r1,@-r10
60 cmp/eq r11,r8
61 bf/s 1b
62 add #28,r10
63 !
64 mov.l @r15+,r11
65 mov.l @r15+,r10
66 mov.l @r15+,r8
67 rts
68 nop
69
70 /*
71 * __kernel_size_t __copy_user(void *to, const
72 * Return the number of bytes NOT copied
73 */
74 #define EX(...) \
75 9999: __VA_ARGS__ ; \
76 .section __ex_table, "a"; \
77 .long 9999b, 6000f ; \
78 .previous
79 #define EX_NO_POP(...) \
80 9999: __VA_ARGS__ ; \
81 .section __ex_table, "a"; \
82 .long 9999b, 6005f ; \
83 .previous
84 ENTRY(__copy_user)
85 ! Check if small number of bytes
86 mov #11,r0
87 mov r4,r3
88 cmp/gt r0,r6 ! r6 (len) > r
89 bf/s .L_cleanup_loop_no_pop
90 add r6,r3 ! last destina
91
92 ! Calculate bytes needed to align to s
93 mov.l r11,@-r15
94 neg r5,r0
95 mov.l r10,@-r15
96 add #4,r0
97 mov.l r9,@-r15
98 and #3,r0
99 mov.l r8,@-r15
100 tst r0,r0
101 bt 2f
102
103 1:
104 ! Copy bytes to long word align src
105 EX( mov.b @r5+,r1 )
106 dt r0
107 add #-1,r6
108 EX( mov.b r1,@r4 )
109 bf/s 1b
110 add #1,r4
111
112 ! Jump to appropriate routine dependin
113 2: mov #3,r1
114 mov r6, r2
115 and r4,r1
116 shlr2 r2
117 shll2 r1
118 mova .L_jump_tbl,r0
119 mov.l @(r0,r1),r1
120 jmp @r1
121 nop
122
123 .align 2
124 .L_jump_tbl:
125 .long .L_dest00
126 .long .L_dest01
127 .long .L_dest10
128 .long .L_dest11
129
130 /*
131 * Come here if there are less than 12 bytes t
132 *
133 * Keep the branch target close, so the bf/s c
134 * and result in a more expensive branch being
135 * fast-path for small copies, the jump via th
136 * default slow-path cleanup. -PFM.
137 */
138 .L_cleanup_loop_no_pop:
139 tst r6,r6 ! Check explic
140 bt 1f
141
142 2:
143 EX_NO_POP( mov.b @r5+,r0 )
144 dt r6
145 EX_NO_POP( mov.b r0,@r4 )
146 bf/s 2b
147 add #1,r4
148
149 1: mov #0,r0 ! normal retur
150 5000:
151
152 # Exception handler:
153 .section .fixup, "ax"
154 6005:
155 mov.l 8000f,r1
156 mov r3,r0
157 jmp @r1
158 sub r4,r0
159 .align 2
160 8000: .long 5000b
161
162 .previous
163 rts
164 nop
165
166 ! Destination = 00
167
168 .L_dest00:
169 ! Skip the large copy for small transf
170 mov #(32+32-4), r0
171 cmp/gt r6, r0 ! r0 (60) > r6
172 bt 1f
173
174 ! Align dest to a 32 byte boundary
175 neg r4,r0
176 add #0x20, r0
177 and #0x1f, r0
178 tst r0, r0
179 bt 2f
180
181 sub r0, r6
182 shlr2 r0
183 3:
184 EX( mov.l @r5+,r1 )
185 dt r0
186 EX( mov.l r1,@r4 )
187 bf/s 3b
188 add #4,r4
189
190 2:
191 EX( mov.l @r5+,r0 )
192 EX( mov.l @r5+,r1 )
193 EX( mov.l @r5+,r2 )
194 EX( mov.l @r5+,r7 )
195 EX( mov.l @r5+,r8 )
196 EX( mov.l @r5+,r9 )
197 EX( mov.l @r5+,r10 )
198 EX( mov.l @r5+,r11 )
199 #ifdef CONFIG_CPU_SH4
200 EX( movca.l r0,@r4 )
201 #else
202 EX( mov.l r0,@r4 )
203 #endif
204 add #-32, r6
205 EX( mov.l r1,@(4,r4) )
206 mov #32, r0
207 EX( mov.l r2,@(8,r4) )
208 cmp/gt r6, r0 ! r0 (32) > r6
209 EX( mov.l r7,@(12,r4) )
210 EX( mov.l r8,@(16,r4) )
211 EX( mov.l r9,@(20,r4) )
212 EX( mov.l r10,@(24,r4) )
213 EX( mov.l r11,@(28,r4) )
214 bf/s 2b
215 add #32,r4
216
217 1: mov r6, r0
218 shlr2 r0
219 tst r0, r0
220 bt .L_cleanup
221 1:
222 EX( mov.l @r5+,r1 )
223 dt r0
224 EX( mov.l r1,@r4 )
225 bf/s 1b
226 add #4,r4
227
228 bra .L_cleanup
229 nop
230
231 ! Destination = 10
232
233 .L_dest10:
234 mov r2,r7
235 shlr2 r7
236 shlr r7
237 tst r7,r7
238 mov #7,r0
239 bt/s 1f
240 and r0,r2
241 2:
242 dt r7
243 #ifdef CONFIG_CPU_LITTLE_ENDIAN
244 EX( mov.l @r5+,r0 )
245 EX( mov.l @r5+,r1 )
246 EX( mov.l @r5+,r8 )
247 EX( mov.l @r5+,r9 )
248 EX( mov.l @r5+,r10 )
249 EX( mov.w r0,@r4 )
250 add #2,r4
251 xtrct r1,r0
252 xtrct r8,r1
253 xtrct r9,r8
254 xtrct r10,r9
255
256 EX( mov.l r0,@r4 )
257 EX( mov.l r1,@(4,r4) )
258 EX( mov.l r8,@(8,r4) )
259 EX( mov.l r9,@(12,r4) )
260
261 EX( mov.l @r5+,r1 )
262 EX( mov.l @r5+,r8 )
263 EX( mov.l @r5+,r0 )
264 xtrct r1,r10
265 xtrct r8,r1
266 xtrct r0,r8
267 shlr16 r0
268 EX( mov.l r10,@(16,r4) )
269 EX( mov.l r1,@(20,r4) )
270 EX( mov.l r8,@(24,r4) )
271 EX( mov.w r0,@(28,r4) )
272 bf/s 2b
273 add #30,r4
274 #else
275 EX( mov.l @(28,r5),r0 )
276 EX( mov.l @(24,r5),r8 )
277 EX( mov.l @(20,r5),r9 )
278 EX( mov.l @(16,r5),r10 )
279 EX( mov.w r0,@(30,r4) )
280 add #-2,r4
281 xtrct r8,r0
282 xtrct r9,r8
283 xtrct r10,r9
284 EX( mov.l r0,@(28,r4) )
285 EX( mov.l r8,@(24,r4) )
286 EX( mov.l r9,@(20,r4) )
287
288 EX( mov.l @(12,r5),r0 )
289 EX( mov.l @(8,r5),r8 )
290 xtrct r0,r10
291 EX( mov.l @(4,r5),r9 )
292 mov.l r10,@(16,r4)
293 EX( mov.l @r5,r10 )
294 xtrct r8,r0
295 xtrct r9,r8
296 xtrct r10,r9
297 EX( mov.l r0,@(12,r4) )
298 EX( mov.l r8,@(8,r4) )
299 swap.w r10,r0
300 EX( mov.l r9,@(4,r4) )
301 EX( mov.w r0,@(2,r4) )
302
303 add #32,r5
304 bf/s 2b
305 add #34,r4
306 #endif
307 tst r2,r2
308 bt .L_cleanup
309
310 1: ! Read longword, write two words per i
311 EX( mov.l @r5+,r0 )
312 dt r2
313 #ifdef CONFIG_CPU_LITTLE_ENDIAN
314 EX( mov.w r0,@r4 )
315 shlr16 r0
316 EX( mov.w r0,@(2,r4) )
317 #else
318 EX( mov.w r0,@(2,r4) )
319 shlr16 r0
320 EX( mov.w r0,@r4 )
321 #endif
322 bf/s 1b
323 add #4,r4
324
325 bra .L_cleanup
326 nop
327
328 ! Destination = 01 or 11
329
330 .L_dest01:
331 .L_dest11:
332 ! Read longword, write byte, word, byt
333 EX( mov.l @r5+,r0 )
334 dt r2
335 #ifdef CONFIG_CPU_LITTLE_ENDIAN
336 EX( mov.b r0,@r4 )
337 shlr8 r0
338 add #1,r4
339 EX( mov.w r0,@r4 )
340 shlr16 r0
341 EX( mov.b r0,@(2,r4) )
342 bf/s .L_dest01
343 add #3,r4
344 #else
345 EX( mov.b r0,@(3,r4) )
346 shlr8 r0
347 swap.w r0,r7
348 EX( mov.b r7,@r4 )
349 add #1,r4
350 EX( mov.w r0,@r4 )
351 bf/s .L_dest01
352 add #3,r4
353 #endif
354
355 ! Cleanup last few bytes
356 .L_cleanup:
357 mov r6,r0
358 and #3,r0
359 tst r0,r0
360 bt .L_exit
361 mov r0,r6
362
363 .L_cleanup_loop:
364 EX( mov.b @r5+,r0 )
365 dt r6
366 EX( mov.b r0,@r4 )
367 bf/s .L_cleanup_loop
368 add #1,r4
369
370 .L_exit:
371 mov #0,r0 ! normal retur
372
373 5000:
374
375 # Exception handler:
376 .section .fixup, "ax"
377 6000:
378 mov.l 8000f,r1
379 mov r3,r0
380 jmp @r1
381 sub r4,r0
382 .align 2
383 8000: .long 5000b
384
385 .previous
386 mov.l @r15+,r8
387 mov.l @r15+,r9
388 mov.l @r15+,r10
389 rts
390 mov.l @r15+,r11
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