Commit | Line | Data |
---|---|---|
51c52e86 ME |
1 | /* |
2 | * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org) | |
3 | * | |
4 | * Modifications for ppc64: | |
5 | * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com> | |
6 | * | |
7 | * Copyright 2008 Michael Ellerman, IBM Corporation. | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU General Public License | |
11 | * as published by the Free Software Foundation; either version | |
12 | * 2 of the License, or (at your option) any later version. | |
13 | */ | |
14 | ||
3880ecb0 | 15 | #include <linux/types.h> |
51c52e86 | 16 | #include <linux/kernel.h> |
362e7701 ME |
17 | #include <linux/string.h> |
18 | #include <linux/init.h> | |
51c52e86 ME |
19 | #include <asm/cputable.h> |
20 | #include <asm/code-patching.h> | |
d715e433 AB |
21 | #include <asm/page.h> |
22 | #include <asm/sections.h> | |
51c52e86 ME |
23 | |
24 | ||
25 | struct fixup_entry { | |
26 | unsigned long mask; | |
27 | unsigned long value; | |
28 | long start_off; | |
29 | long end_off; | |
fac23fe4 ME |
30 | long alt_start_off; |
31 | long alt_end_off; | |
51c52e86 ME |
32 | }; |
33 | ||
9b1a735d | 34 | static unsigned int *calc_addr(struct fixup_entry *fcur, long offset) |
51c52e86 | 35 | { |
9b1a735d ME |
36 | /* |
37 | * We store the offset to the code as a negative offset from | |
38 | * the start of the alt_entry, to support the VDSO. This | |
39 | * routine converts that back into an actual address. | |
40 | */ | |
41 | return (unsigned int *)((unsigned long)fcur + offset); | |
42 | } | |
43 | ||
44 | static int patch_alt_instruction(unsigned int *src, unsigned int *dest, | |
45 | unsigned int *alt_start, unsigned int *alt_end) | |
46 | { | |
47 | unsigned int instr; | |
48 | ||
49 | instr = *src; | |
50 | ||
51 | if (instr_is_relative_branch(*src)) { | |
52 | unsigned int *target = (unsigned int *)branch_target(src); | |
53 | ||
54 | /* Branch within the section doesn't need translating */ | |
55 | if (target < alt_start || target >= alt_end) { | |
56 | instr = translate_branch(dest, src); | |
57 | if (!instr) | |
58 | return 1; | |
59 | } | |
60 | } | |
61 | ||
62 | patch_instruction(dest, instr); | |
63 | ||
64 | return 0; | |
65 | } | |
66 | ||
67 | static int patch_feature_section(unsigned long value, struct fixup_entry *fcur) | |
68 | { | |
69 | unsigned int *start, *end, *alt_start, *alt_end, *src, *dest; | |
70 | ||
71 | start = calc_addr(fcur, fcur->start_off); | |
72 | end = calc_addr(fcur, fcur->end_off); | |
73 | alt_start = calc_addr(fcur, fcur->alt_start_off); | |
74 | alt_end = calc_addr(fcur, fcur->alt_end_off); | |
75 | ||
76 | if ((alt_end - alt_start) > (end - start)) | |
77 | return 1; | |
51c52e86 ME |
78 | |
79 | if ((value & fcur->mask) == fcur->value) | |
9b1a735d | 80 | return 0; |
51c52e86 | 81 | |
9b1a735d ME |
82 | src = alt_start; |
83 | dest = start; | |
51c52e86 | 84 | |
9b1a735d ME |
85 | for (; src < alt_end; src++, dest++) { |
86 | if (patch_alt_instruction(src, dest, alt_start, alt_end)) | |
87 | return 1; | |
51c52e86 | 88 | } |
9b1a735d ME |
89 | |
90 | for (; dest < end; dest++) | |
16c57b36 | 91 | patch_instruction(dest, PPC_INST_NOP); |
9b1a735d ME |
92 | |
93 | return 0; | |
51c52e86 ME |
94 | } |
95 | ||
96 | void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end) | |
97 | { | |
98 | struct fixup_entry *fcur, *fend; | |
99 | ||
100 | fcur = fixup_start; | |
101 | fend = fixup_end; | |
102 | ||
9b1a735d ME |
103 | for (; fcur < fend; fcur++) { |
104 | if (patch_feature_section(value, fcur)) { | |
1856c020 | 105 | WARN_ON(1); |
9b1a735d ME |
106 | printk("Unable to patch feature section at %p - %p" \ |
107 | " with %p - %p\n", | |
108 | calc_addr(fcur, fcur->start_off), | |
109 | calc_addr(fcur, fcur->end_off), | |
110 | calc_addr(fcur, fcur->alt_start_off), | |
111 | calc_addr(fcur, fcur->alt_end_off)); | |
112 | } | |
113 | } | |
51c52e86 | 114 | } |
362e7701 | 115 | |
2d1b2027 KG |
116 | void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end) |
117 | { | |
3d98ffbf BH |
118 | long *start, *end; |
119 | unsigned int *dest; | |
2d1b2027 KG |
120 | |
121 | if (!(value & CPU_FTR_LWSYNC)) | |
122 | return ; | |
123 | ||
124 | start = fixup_start; | |
125 | end = fixup_end; | |
126 | ||
127 | for (; start < end; start++) { | |
128 | dest = (void *)start + *start; | |
16c57b36 | 129 | patch_instruction(dest, PPC_INST_LWSYNC); |
2d1b2027 KG |
130 | } |
131 | } | |
132 | ||
d715e433 AB |
133 | void do_final_fixups(void) |
134 | { | |
135 | #if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE) | |
136 | int *src, *dest; | |
137 | unsigned long length; | |
138 | ||
139 | if (PHYSICAL_START == 0) | |
140 | return; | |
141 | ||
142 | src = (int *)(KERNELBASE + PHYSICAL_START); | |
143 | dest = (int *)KERNELBASE; | |
144 | length = (__end_interrupts - _stext) / sizeof(int); | |
145 | ||
146 | while (length--) { | |
147 | patch_instruction(dest, *src); | |
148 | src++; | |
149 | dest++; | |
150 | } | |
151 | #endif | |
152 | } | |
153 | ||
362e7701 ME |
154 | #ifdef CONFIG_FTR_FIXUP_SELFTEST |
155 | ||
156 | #define check(x) \ | |
157 | if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__); | |
158 | ||
159 | /* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */ | |
160 | static struct fixup_entry fixup; | |
161 | ||
162 | static long calc_offset(struct fixup_entry *entry, unsigned int *p) | |
163 | { | |
164 | return (unsigned long)p - (unsigned long)entry; | |
165 | } | |
166 | ||
e51df2c1 | 167 | static void test_basic_patching(void) |
362e7701 ME |
168 | { |
169 | extern unsigned int ftr_fixup_test1; | |
170 | extern unsigned int end_ftr_fixup_test1; | |
171 | extern unsigned int ftr_fixup_test1_orig; | |
172 | extern unsigned int ftr_fixup_test1_expected; | |
173 | int size = &end_ftr_fixup_test1 - &ftr_fixup_test1; | |
174 | ||
175 | fixup.value = fixup.mask = 8; | |
176 | fixup.start_off = calc_offset(&fixup, &ftr_fixup_test1 + 1); | |
177 | fixup.end_off = calc_offset(&fixup, &ftr_fixup_test1 + 2); | |
178 | fixup.alt_start_off = fixup.alt_end_off = 0; | |
179 | ||
180 | /* Sanity check */ | |
181 | check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0); | |
182 | ||
183 | /* Check we don't patch if the value matches */ | |
184 | patch_feature_section(8, &fixup); | |
185 | check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0); | |
186 | ||
187 | /* Check we do patch if the value doesn't match */ | |
188 | patch_feature_section(0, &fixup); | |
189 | check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0); | |
190 | ||
191 | /* Check we do patch if the mask doesn't match */ | |
192 | memcpy(&ftr_fixup_test1, &ftr_fixup_test1_orig, size); | |
193 | check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_orig, size) == 0); | |
194 | patch_feature_section(~8, &fixup); | |
195 | check(memcmp(&ftr_fixup_test1, &ftr_fixup_test1_expected, size) == 0); | |
196 | } | |
197 | ||
198 | static void test_alternative_patching(void) | |
199 | { | |
200 | extern unsigned int ftr_fixup_test2; | |
201 | extern unsigned int end_ftr_fixup_test2; | |
202 | extern unsigned int ftr_fixup_test2_orig; | |
203 | extern unsigned int ftr_fixup_test2_alt; | |
204 | extern unsigned int ftr_fixup_test2_expected; | |
205 | int size = &end_ftr_fixup_test2 - &ftr_fixup_test2; | |
206 | ||
207 | fixup.value = fixup.mask = 0xF; | |
208 | fixup.start_off = calc_offset(&fixup, &ftr_fixup_test2 + 1); | |
209 | fixup.end_off = calc_offset(&fixup, &ftr_fixup_test2 + 2); | |
210 | fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test2_alt); | |
211 | fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test2_alt + 1); | |
212 | ||
213 | /* Sanity check */ | |
214 | check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0); | |
215 | ||
216 | /* Check we don't patch if the value matches */ | |
217 | patch_feature_section(0xF, &fixup); | |
218 | check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0); | |
219 | ||
220 | /* Check we do patch if the value doesn't match */ | |
221 | patch_feature_section(0, &fixup); | |
222 | check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0); | |
223 | ||
224 | /* Check we do patch if the mask doesn't match */ | |
225 | memcpy(&ftr_fixup_test2, &ftr_fixup_test2_orig, size); | |
226 | check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_orig, size) == 0); | |
227 | patch_feature_section(~0xF, &fixup); | |
228 | check(memcmp(&ftr_fixup_test2, &ftr_fixup_test2_expected, size) == 0); | |
229 | } | |
230 | ||
231 | static void test_alternative_case_too_big(void) | |
232 | { | |
233 | extern unsigned int ftr_fixup_test3; | |
234 | extern unsigned int end_ftr_fixup_test3; | |
235 | extern unsigned int ftr_fixup_test3_orig; | |
236 | extern unsigned int ftr_fixup_test3_alt; | |
237 | int size = &end_ftr_fixup_test3 - &ftr_fixup_test3; | |
238 | ||
239 | fixup.value = fixup.mask = 0xC; | |
240 | fixup.start_off = calc_offset(&fixup, &ftr_fixup_test3 + 1); | |
241 | fixup.end_off = calc_offset(&fixup, &ftr_fixup_test3 + 2); | |
242 | fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test3_alt); | |
243 | fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test3_alt + 2); | |
244 | ||
245 | /* Sanity check */ | |
246 | check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0); | |
247 | ||
248 | /* Expect nothing to be patched, and the error returned to us */ | |
249 | check(patch_feature_section(0xF, &fixup) == 1); | |
250 | check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0); | |
251 | check(patch_feature_section(0, &fixup) == 1); | |
252 | check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0); | |
253 | check(patch_feature_section(~0xF, &fixup) == 1); | |
254 | check(memcmp(&ftr_fixup_test3, &ftr_fixup_test3_orig, size) == 0); | |
255 | } | |
256 | ||
257 | static void test_alternative_case_too_small(void) | |
258 | { | |
259 | extern unsigned int ftr_fixup_test4; | |
260 | extern unsigned int end_ftr_fixup_test4; | |
261 | extern unsigned int ftr_fixup_test4_orig; | |
262 | extern unsigned int ftr_fixup_test4_alt; | |
263 | extern unsigned int ftr_fixup_test4_expected; | |
264 | int size = &end_ftr_fixup_test4 - &ftr_fixup_test4; | |
265 | unsigned long flag; | |
266 | ||
267 | /* Check a high-bit flag */ | |
268 | flag = 1UL << ((sizeof(unsigned long) - 1) * 8); | |
269 | fixup.value = fixup.mask = flag; | |
270 | fixup.start_off = calc_offset(&fixup, &ftr_fixup_test4 + 1); | |
271 | fixup.end_off = calc_offset(&fixup, &ftr_fixup_test4 + 5); | |
272 | fixup.alt_start_off = calc_offset(&fixup, &ftr_fixup_test4_alt); | |
273 | fixup.alt_end_off = calc_offset(&fixup, &ftr_fixup_test4_alt + 2); | |
274 | ||
275 | /* Sanity check */ | |
276 | check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0); | |
277 | ||
278 | /* Check we don't patch if the value matches */ | |
279 | patch_feature_section(flag, &fixup); | |
280 | check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0); | |
281 | ||
282 | /* Check we do patch if the value doesn't match */ | |
283 | patch_feature_section(0, &fixup); | |
284 | check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0); | |
285 | ||
286 | /* Check we do patch if the mask doesn't match */ | |
287 | memcpy(&ftr_fixup_test4, &ftr_fixup_test4_orig, size); | |
288 | check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_orig, size) == 0); | |
289 | patch_feature_section(~flag, &fixup); | |
290 | check(memcmp(&ftr_fixup_test4, &ftr_fixup_test4_expected, size) == 0); | |
291 | } | |
292 | ||
293 | static void test_alternative_case_with_branch(void) | |
294 | { | |
295 | extern unsigned int ftr_fixup_test5; | |
296 | extern unsigned int end_ftr_fixup_test5; | |
297 | extern unsigned int ftr_fixup_test5_expected; | |
298 | int size = &end_ftr_fixup_test5 - &ftr_fixup_test5; | |
299 | ||
300 | check(memcmp(&ftr_fixup_test5, &ftr_fixup_test5_expected, size) == 0); | |
301 | } | |
302 | ||
303 | static void test_alternative_case_with_external_branch(void) | |
304 | { | |
305 | extern unsigned int ftr_fixup_test6; | |
306 | extern unsigned int end_ftr_fixup_test6; | |
307 | extern unsigned int ftr_fixup_test6_expected; | |
308 | int size = &end_ftr_fixup_test6 - &ftr_fixup_test6; | |
309 | ||
310 | check(memcmp(&ftr_fixup_test6, &ftr_fixup_test6_expected, size) == 0); | |
311 | } | |
312 | ||
313 | static void test_cpu_macros(void) | |
314 | { | |
3880ecb0 SR |
315 | extern u8 ftr_fixup_test_FTR_macros; |
316 | extern u8 ftr_fixup_test_FTR_macros_expected; | |
362e7701 ME |
317 | unsigned long size = &ftr_fixup_test_FTR_macros_expected - |
318 | &ftr_fixup_test_FTR_macros; | |
319 | ||
320 | /* The fixups have already been done for us during boot */ | |
321 | check(memcmp(&ftr_fixup_test_FTR_macros, | |
322 | &ftr_fixup_test_FTR_macros_expected, size) == 0); | |
323 | } | |
324 | ||
325 | static void test_fw_macros(void) | |
326 | { | |
327 | #ifdef CONFIG_PPC64 | |
3880ecb0 SR |
328 | extern u8 ftr_fixup_test_FW_FTR_macros; |
329 | extern u8 ftr_fixup_test_FW_FTR_macros_expected; | |
362e7701 ME |
330 | unsigned long size = &ftr_fixup_test_FW_FTR_macros_expected - |
331 | &ftr_fixup_test_FW_FTR_macros; | |
332 | ||
333 | /* The fixups have already been done for us during boot */ | |
334 | check(memcmp(&ftr_fixup_test_FW_FTR_macros, | |
335 | &ftr_fixup_test_FW_FTR_macros_expected, size) == 0); | |
336 | #endif | |
337 | } | |
338 | ||
2d1b2027 KG |
339 | static void test_lwsync_macros(void) |
340 | { | |
3880ecb0 SR |
341 | extern u8 lwsync_fixup_test; |
342 | extern u8 end_lwsync_fixup_test; | |
343 | extern u8 lwsync_fixup_test_expected_LWSYNC; | |
344 | extern u8 lwsync_fixup_test_expected_SYNC; | |
2d1b2027 KG |
345 | unsigned long size = &end_lwsync_fixup_test - |
346 | &lwsync_fixup_test; | |
347 | ||
348 | /* The fixups have already been done for us during boot */ | |
349 | if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) { | |
350 | check(memcmp(&lwsync_fixup_test, | |
351 | &lwsync_fixup_test_expected_LWSYNC, size) == 0); | |
352 | } else { | |
353 | check(memcmp(&lwsync_fixup_test, | |
354 | &lwsync_fixup_test_expected_SYNC, size) == 0); | |
355 | } | |
356 | } | |
357 | ||
362e7701 ME |
358 | static int __init test_feature_fixups(void) |
359 | { | |
360 | printk(KERN_DEBUG "Running feature fixup self-tests ...\n"); | |
361 | ||
362 | test_basic_patching(); | |
363 | test_alternative_patching(); | |
364 | test_alternative_case_too_big(); | |
365 | test_alternative_case_too_small(); | |
366 | test_alternative_case_with_branch(); | |
367 | test_alternative_case_with_external_branch(); | |
368 | test_cpu_macros(); | |
369 | test_fw_macros(); | |
2d1b2027 | 370 | test_lwsync_macros(); |
362e7701 ME |
371 | |
372 | return 0; | |
373 | } | |
374 | late_initcall(test_feature_fixups); | |
375 | ||
376 | #endif /* CONFIG_FTR_FIXUP_SELFTEST */ |