1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
4  *
5  *  Modifications for ppc64:
6  *      Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
7  *
8  *  Copyright 2008 Michael Ellerman, IBM Corporation.
9  */
10 
11 #include <linux/types.h>
12 #include <linux/jump_label.h>
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/init.h>
16 #include <linux/sched/mm.h>
17 #include <asm/cputable.h>
18 #include <asm/code-patching.h>
19 #include <asm/page.h>
20 #include <asm/sections.h>
21 #include <asm/setup.h>
22 #include <asm/security_features.h>
23 #include <asm/firmware.h>
24 #include <asm/inst.h>
25 
26 struct fixup_entry {
27 	unsigned long	mask;
28 	unsigned long	value;
29 	long		start_off;
30 	long		end_off;
31 	long		alt_start_off;
32 	long		alt_end_off;
33 };
34 
35 static struct ppc_inst *calc_addr(struct fixup_entry *fcur, long offset)
36 {
37 	/*
38 	 * We store the offset to the code as a negative offset from
39 	 * the start of the alt_entry, to support the VDSO. This
40 	 * routine converts that back into an actual address.
41 	 */
42 	return (struct ppc_inst *)((unsigned long)fcur + offset);
43 }
44 
45 static int patch_alt_instruction(struct ppc_inst *src, struct ppc_inst *dest,
46 				 struct ppc_inst *alt_start, struct ppc_inst *alt_end)
47 {
48 	int err;
49 	struct ppc_inst instr;
50 
51 	instr = ppc_inst_read(src);
52 
53 	if (instr_is_relative_branch(*src)) {
54 		struct ppc_inst *target = (struct ppc_inst *)branch_target(src);
55 
56 		/* Branch within the section doesn't need translating */
57 		if (target < alt_start || target > alt_end) {
58 			err = translate_branch(&instr, dest, src);
59 			if (err)
60 				return 1;
61 		}
62 	}
63 
64 	raw_patch_instruction(dest, instr);
65 
66 	return 0;
67 }
68 
69 static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
70 {
71 	struct ppc_inst *start, *end, *alt_start, *alt_end, *src, *dest, nop;
72 
73 	start = calc_addr(fcur, fcur->start_off);
74 	end = calc_addr(fcur, fcur->end_off);
75 	alt_start = calc_addr(fcur, fcur->alt_start_off);
76 	alt_end = calc_addr(fcur, fcur->alt_end_off);
77 
78 	if ((alt_end - alt_start) > (end - start))
79 		return 1;
80 
81 	if ((value & fcur->mask) == fcur->value)
82 		return 0;
83 
84 	src = alt_start;
85 	dest = start;
86 
87 	for (; src < alt_end; src = ppc_inst_next(src, src),
88 			      dest = ppc_inst_next(dest, dest)) {
89 		if (patch_alt_instruction(src, dest, alt_start, alt_end))
90 			return 1;
91 	}
92 
93 	nop = ppc_inst(PPC_INST_NOP);
94 	for (; dest < end; dest = ppc_inst_next(dest, &nop))
95 		raw_patch_instruction(dest, nop);
96 
97 	return 0;
98 }
99 
100 void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
101 {
102 	struct fixup_entry *fcur, *fend;
103 
104 	fcur = fixup_start;
105 	fend = fixup_end;
106 
107 	for (; fcur < fend; fcur++) {
108 		if (patch_feature_section(value, fcur)) {
109 			WARN_ON(1);
110 			printk("Unable to patch feature section at %p - %p" \
111 				" with %p - %p\n",
112 				calc_addr(fcur, fcur->start_off),
113 				calc_addr(fcur, fcur->end_off),
114 				calc_addr(fcur, fcur->alt_start_off),
115 				calc_addr(fcur, fcur->alt_end_off));
116 		}
117 	}
118 }
119 
120 #ifdef CONFIG_PPC_BOOK3S_64
121 static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
122 {
123 	unsigned int instrs[3], *dest;
124 	long *start, *end;
125 	int i;
126 
127 	start = PTRRELOC(&__start___stf_entry_barrier_fixup),
128 	end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
129 
130 	instrs[0] = 0x60000000; /* nop */
131 	instrs[1] = 0x60000000; /* nop */
132 	instrs[2] = 0x60000000; /* nop */
133 
134 	i = 0;
135 	if (types & STF_BARRIER_FALLBACK) {
136 		instrs[i++] = 0x7d4802a6; /* mflr r10		*/
137 		instrs[i++] = 0x60000000; /* branch patched below */
138 		instrs[i++] = 0x7d4803a6; /* mtlr r10		*/
139 	} else if (types & STF_BARRIER_EIEIO) {
140 		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
141 	} else if (types & STF_BARRIER_SYNC_ORI) {
142 		instrs[i++] = 0x7c0004ac; /* hwsync		*/
143 		instrs[i++] = 0xe94d0000; /* ld r10,0(r13)	*/
144 		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
145 	}
146 
147 	for (i = 0; start < end; start++, i++) {
148 		dest = (void *)start + *start;
149 
150 		pr_devel("patching dest %lx\n", (unsigned long)dest);
151 
152 		patch_instruction((struct ppc_inst *)dest, ppc_inst(instrs[0]));
153 
154 		if (types & STF_BARRIER_FALLBACK)
155 			patch_branch((struct ppc_inst *)(dest + 1),
156 				     (unsigned long)&stf_barrier_fallback,
157 				     BRANCH_SET_LINK);
158 		else
159 			patch_instruction((struct ppc_inst *)(dest + 1),
160 					  ppc_inst(instrs[1]));
161 
162 		patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
163 	}
164 
165 	printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
166 		(types == STF_BARRIER_NONE)                  ? "no" :
167 		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
168 		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
169 		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
170 		                                           : "unknown");
171 }
172 
173 static void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
174 {
175 	unsigned int instrs[6], *dest;
176 	long *start, *end;
177 	int i;
178 
179 	start = PTRRELOC(&__start___stf_exit_barrier_fixup),
180 	end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
181 
182 	instrs[0] = 0x60000000; /* nop */
183 	instrs[1] = 0x60000000; /* nop */
184 	instrs[2] = 0x60000000; /* nop */
185 	instrs[3] = 0x60000000; /* nop */
186 	instrs[4] = 0x60000000; /* nop */
187 	instrs[5] = 0x60000000; /* nop */
188 
189 	i = 0;
190 	if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
191 		if (cpu_has_feature(CPU_FTR_HVMODE)) {
192 			instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
193 			instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
194 		} else {
195 			instrs[i++] = 0x7db243a6; /* mtsprg 2,r13	*/
196 			instrs[i++] = 0x7db142a6; /* mfsprg r13,1    */
197 	        }
198 		instrs[i++] = 0x7c0004ac; /* hwsync		*/
199 		instrs[i++] = 0xe9ad0000; /* ld r13,0(r13)	*/
200 		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
201 		if (cpu_has_feature(CPU_FTR_HVMODE)) {
202 			instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
203 		} else {
204 			instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
205 		}
206 	} else if (types & STF_BARRIER_EIEIO) {
207 		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
208 	}
209 
210 	for (i = 0; start < end; start++, i++) {
211 		dest = (void *)start + *start;
212 
213 		pr_devel("patching dest %lx\n", (unsigned long)dest);
214 
215 		patch_instruction((struct ppc_inst *)dest, ppc_inst(instrs[0]));
216 		patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
217 		patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
218 		patch_instruction((struct ppc_inst *)(dest + 3), ppc_inst(instrs[3]));
219 		patch_instruction((struct ppc_inst *)(dest + 4), ppc_inst(instrs[4]));
220 		patch_instruction((struct ppc_inst *)(dest + 5), ppc_inst(instrs[5]));
221 	}
222 	printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
223 		(types == STF_BARRIER_NONE)                  ? "no" :
224 		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
225 		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
226 		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
227 		                                           : "unknown");
228 }
229 
230 
231 void do_stf_barrier_fixups(enum stf_barrier_type types)
232 {
233 	do_stf_entry_barrier_fixups(types);
234 	do_stf_exit_barrier_fixups(types);
235 }
236 
237 void do_rfi_flush_fixups(enum l1d_flush_type types)
238 {
239 	unsigned int instrs[3], *dest;
240 	long *start, *end;
241 	int i;
242 
243 	start = PTRRELOC(&__start___rfi_flush_fixup),
244 	end = PTRRELOC(&__stop___rfi_flush_fixup);
245 
246 	instrs[0] = 0x60000000; /* nop */
247 	instrs[1] = 0x60000000; /* nop */
248 	instrs[2] = 0x60000000; /* nop */
249 
250 	if (types & L1D_FLUSH_FALLBACK)
251 		/* b .+16 to fallback flush */
252 		instrs[0] = 0x48000010;
253 
254 	i = 0;
255 	if (types & L1D_FLUSH_ORI) {
256 		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
257 		instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
258 	}
259 
260 	if (types & L1D_FLUSH_MTTRIG)
261 		instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
262 
263 	for (i = 0; start < end; start++, i++) {
264 		dest = (void *)start + *start;
265 
266 		pr_devel("patching dest %lx\n", (unsigned long)dest);
267 
268 		patch_instruction((struct ppc_inst *)dest, ppc_inst(instrs[0]));
269 		patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instrs[1]));
270 		patch_instruction((struct ppc_inst *)(dest + 2), ppc_inst(instrs[2]));
271 	}
272 
273 	printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
274 		(types == L1D_FLUSH_NONE)       ? "no" :
275 		(types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
276 		(types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
277 							? "ori+mttrig type"
278 							: "ori type" :
279 		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
280 						: "unknown");
281 }
282 
283 void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
284 {
285 	unsigned int instr, *dest;
286 	long *start, *end;
287 	int i;
288 
289 	start = fixup_start;
290 	end = fixup_end;
291 
292 	instr = 0x60000000; /* nop */
293 
294 	if (enable) {
295 		pr_info("barrier-nospec: using ORI speculation barrier\n");
296 		instr = 0x63ff0000; /* ori 31,31,0 speculation barrier */
297 	}
298 
299 	for (i = 0; start < end; start++, i++) {
300 		dest = (void *)start + *start;
301 
302 		pr_devel("patching dest %lx\n", (unsigned long)dest);
303 		patch_instruction((struct ppc_inst *)dest, ppc_inst(instr));
304 	}
305 
306 	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
307 }
308 
309 #endif /* CONFIG_PPC_BOOK3S_64 */
310 
311 #ifdef CONFIG_PPC_BARRIER_NOSPEC
312 void do_barrier_nospec_fixups(bool enable)
313 {
314 	void *start, *end;
315 
316 	start = PTRRELOC(&__start___barrier_nospec_fixup),
317 	end = PTRRELOC(&__stop___barrier_nospec_fixup);
318 
319 	do_barrier_nospec_fixups_range(enable, start, end);
320 }
321 #endif /* CONFIG_PPC_BARRIER_NOSPEC */
322 
323 #ifdef CONFIG_PPC_FSL_BOOK3E
324 void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
325 {
326 	unsigned int instr[2], *dest;
327 	long *start, *end;
328 	int i;
329 
330 	start = fixup_start;
331 	end = fixup_end;
332 
333 	instr[0] = PPC_INST_NOP;
334 	instr[1] = PPC_INST_NOP;
335 
336 	if (enable) {
337 		pr_info("barrier-nospec: using isync; sync as speculation barrier\n");
338 		instr[0] = PPC_INST_ISYNC;
339 		instr[1] = PPC_INST_SYNC;
340 	}
341 
342 	for (i = 0; start < end; start++, i++) {
343 		dest = (void *)start + *start;
344 
345 		pr_devel("patching dest %lx\n", (unsigned long)dest);
346 		patch_instruction((struct ppc_inst *)dest, ppc_inst(instr[0]));
347 		patch_instruction((struct ppc_inst *)(dest + 1), ppc_inst(instr[1]));
348 	}
349 
350 	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
351 }
352 
353 static void patch_btb_flush_section(long *curr)
354 {
355 	unsigned int *start, *end;
356 
357 	start = (void *)curr + *curr;
358 	end = (void *)curr + *(curr + 1);
359 	for (; start < end; start++) {
360 		pr_devel("patching dest %lx\n", (unsigned long)start);
361 		patch_instruction((struct ppc_inst *)start, ppc_inst(PPC_INST_NOP));
362 	}
363 }
364 
365 void do_btb_flush_fixups(void)
366 {
367 	long *start, *end;
368 
369 	start = PTRRELOC(&__start__btb_flush_fixup);
370 	end = PTRRELOC(&__stop__btb_flush_fixup);
371 
372 	for (; start < end; start += 2)
373 		patch_btb_flush_section(start);
374 }
375 #endif /* CONFIG_PPC_FSL_BOOK3E */
376 
377 void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
378 {
379 	long *start, *end;
380 	struct ppc_inst *dest;
381 
382 	if (!(value & CPU_FTR_LWSYNC))
383 		return ;
384 
385 	start = fixup_start;
386 	end = fixup_end;
387 
388 	for (; start < end; start++) {
389 		dest = (void *)start + *start;
390 		raw_patch_instruction(dest, ppc_inst(PPC_INST_LWSYNC));
391 	}
392 }
393 
394 static void do_final_fixups(void)
395 {
396 #if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
397 	struct ppc_inst inst, *src, *dest, *end;
398 
399 	if (PHYSICAL_START == 0)
400 		return;
401 
402 	src = (struct ppc_inst *)(KERNELBASE + PHYSICAL_START);
403 	dest = (struct ppc_inst *)KERNELBASE;
404 	end = (void *)src + (__end_interrupts - _stext);
405 
406 	while (src < end) {
407 		inst = ppc_inst_read(src);
408 		raw_patch_instruction(dest, inst);
409 		src = ppc_inst_next(src, src);
410 		dest = ppc_inst_next(dest, dest);
411 	}
412 #endif
413 }
414 
415 static unsigned long __initdata saved_cpu_features;
416 static unsigned int __initdata saved_mmu_features;
417 #ifdef CONFIG_PPC64
418 static unsigned long __initdata saved_firmware_features;
419 #endif
420 
421 void __init apply_feature_fixups(void)
422 {
423 	struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));
424 
425 	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
426 	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
427 
428 	/*
429 	 * Apply the CPU-specific and firmware specific fixups to kernel text
430 	 * (nop out sections not relevant to this CPU or this firmware).
431 	 */
432 	do_feature_fixups(spec->cpu_features,
433 			  PTRRELOC(&__start___ftr_fixup),
434 			  PTRRELOC(&__stop___ftr_fixup));
435 
436 	do_feature_fixups(spec->mmu_features,
437 			  PTRRELOC(&__start___mmu_ftr_fixup),
438 			  PTRRELOC(&__stop___mmu_ftr_fixup));
439 
440 	do_lwsync_fixups(spec->cpu_features,
441 			 PTRRELOC(&__start___lwsync_fixup),
442 			 PTRRELOC(&__stop___lwsync_fixup));
443 
444 #ifdef CONFIG_PPC64
445 	saved_firmware_features = powerpc_firmware_features;
446 	do_feature_fixups(powerpc_firmware_features,
447 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
448 #endif
449 	do_final_fixups();
450 }
451 
452 void __init setup_feature_keys(void)
453 {
454 	/*
455 	 * Initialise jump label. This causes all the cpu/mmu_has_feature()
456 	 * checks to take on their correct polarity based on the current set of
457 	 * CPU/MMU features.
458 	 */
459 	jump_label_init();
460 	cpu_feature_keys_init();
461 	mmu_feature_keys_init();
462 }
463 
464 static int __init check_features(void)
465 {
466 	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
467 	     "CPU features changed after feature patching!\n");
468 	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
469 	     "MMU features changed after feature patching!\n");
470 #ifdef CONFIG_PPC64
471 	WARN(saved_firmware_features != powerpc_firmware_features,
472 	     "Firmware features changed after feature patching!\n");
473 #endif
474 
475 	return 0;
476 }
477 late_initcall(check_features);
478 
479 #ifdef CONFIG_FTR_FIXUP_SELFTEST
480 
481 #define check(x)	\
482 	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
483 
484 /* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
485 static struct fixup_entry fixup;
486 
487 static long calc_offset(struct fixup_entry *entry, unsigned int *p)
488 {
489 	return (unsigned long)p - (unsigned long)entry;
490 }
491 
492 static void test_basic_patching(void)
493 {
494 	extern unsigned int ftr_fixup_test1[];
495 	extern unsigned int end_ftr_fixup_test1[];
496 	extern unsigned int ftr_fixup_test1_orig[];
497 	extern unsigned int ftr_fixup_test1_expected[];
498 	int size = 4 * (end_ftr_fixup_test1 - ftr_fixup_test1);
499 
500 	fixup.value = fixup.mask = 8;
501 	fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
502 	fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
503 	fixup.alt_start_off = fixup.alt_end_off = 0;
504 
505 	/* Sanity check */
506 	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
507 
508 	/* Check we don't patch if the value matches */
509 	patch_feature_section(8, &fixup);
510 	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
511 
512 	/* Check we do patch if the value doesn't match */
513 	patch_feature_section(0, &fixup);
514 	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
515 
516 	/* Check we do patch if the mask doesn't match */
517 	memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
518 	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
519 	patch_feature_section(~8, &fixup);
520 	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
521 }
522 
523 static void test_alternative_patching(void)
524 {
525 	extern unsigned int ftr_fixup_test2[];
526 	extern unsigned int end_ftr_fixup_test2[];
527 	extern unsigned int ftr_fixup_test2_orig[];
528 	extern unsigned int ftr_fixup_test2_alt[];
529 	extern unsigned int ftr_fixup_test2_expected[];
530 	int size = 4 * (end_ftr_fixup_test2 - ftr_fixup_test2);
531 
532 	fixup.value = fixup.mask = 0xF;
533 	fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
534 	fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
535 	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
536 	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
537 
538 	/* Sanity check */
539 	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
540 
541 	/* Check we don't patch if the value matches */
542 	patch_feature_section(0xF, &fixup);
543 	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
544 
545 	/* Check we do patch if the value doesn't match */
546 	patch_feature_section(0, &fixup);
547 	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
548 
549 	/* Check we do patch if the mask doesn't match */
550 	memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
551 	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
552 	patch_feature_section(~0xF, &fixup);
553 	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
554 }
555 
556 static void test_alternative_case_too_big(void)
557 {
558 	extern unsigned int ftr_fixup_test3[];
559 	extern unsigned int end_ftr_fixup_test3[];
560 	extern unsigned int ftr_fixup_test3_orig[];
561 	extern unsigned int ftr_fixup_test3_alt[];
562 	int size = 4 * (end_ftr_fixup_test3 - ftr_fixup_test3);
563 
564 	fixup.value = fixup.mask = 0xC;
565 	fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
566 	fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
567 	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
568 	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
569 
570 	/* Sanity check */
571 	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
572 
573 	/* Expect nothing to be patched, and the error returned to us */
574 	check(patch_feature_section(0xF, &fixup) == 1);
575 	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
576 	check(patch_feature_section(0, &fixup) == 1);
577 	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
578 	check(patch_feature_section(~0xF, &fixup) == 1);
579 	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
580 }
581 
582 static void test_alternative_case_too_small(void)
583 {
584 	extern unsigned int ftr_fixup_test4[];
585 	extern unsigned int end_ftr_fixup_test4[];
586 	extern unsigned int ftr_fixup_test4_orig[];
587 	extern unsigned int ftr_fixup_test4_alt[];
588 	extern unsigned int ftr_fixup_test4_expected[];
589 	int size = 4 * (end_ftr_fixup_test4 - ftr_fixup_test4);
590 	unsigned long flag;
591 
592 	/* Check a high-bit flag */
593 	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
594 	fixup.value = fixup.mask = flag;
595 	fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
596 	fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
597 	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
598 	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
599 
600 	/* Sanity check */
601 	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
602 
603 	/* Check we don't patch if the value matches */
604 	patch_feature_section(flag, &fixup);
605 	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
606 
607 	/* Check we do patch if the value doesn't match */
608 	patch_feature_section(0, &fixup);
609 	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
610 
611 	/* Check we do patch if the mask doesn't match */
612 	memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
613 	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
614 	patch_feature_section(~flag, &fixup);
615 	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
616 }
617 
618 static void test_alternative_case_with_branch(void)
619 {
620 	extern unsigned int ftr_fixup_test5[];
621 	extern unsigned int end_ftr_fixup_test5[];
622 	extern unsigned int ftr_fixup_test5_expected[];
623 	int size = 4 * (end_ftr_fixup_test5 - ftr_fixup_test5);
624 
625 	check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
626 }
627 
628 static void test_alternative_case_with_external_branch(void)
629 {
630 	extern unsigned int ftr_fixup_test6[];
631 	extern unsigned int end_ftr_fixup_test6[];
632 	extern unsigned int ftr_fixup_test6_expected[];
633 	int size = 4 * (end_ftr_fixup_test6 - ftr_fixup_test6);
634 
635 	check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
636 }
637 
638 static void test_alternative_case_with_branch_to_end(void)
639 {
640 	extern unsigned int ftr_fixup_test7[];
641 	extern unsigned int end_ftr_fixup_test7[];
642 	extern unsigned int ftr_fixup_test7_expected[];
643 	int size = 4 * (end_ftr_fixup_test7 - ftr_fixup_test7);
644 
645 	check(memcmp(ftr_fixup_test7, ftr_fixup_test7_expected, size) == 0);
646 }
647 
648 static void test_cpu_macros(void)
649 {
650 	extern u8 ftr_fixup_test_FTR_macros[];
651 	extern u8 ftr_fixup_test_FTR_macros_expected[];
652 	unsigned long size = ftr_fixup_test_FTR_macros_expected -
653 			     ftr_fixup_test_FTR_macros;
654 
655 	/* The fixups have already been done for us during boot */
656 	check(memcmp(ftr_fixup_test_FTR_macros,
657 		     ftr_fixup_test_FTR_macros_expected, size) == 0);
658 }
659 
660 static void test_fw_macros(void)
661 {
662 #ifdef CONFIG_PPC64
663 	extern u8 ftr_fixup_test_FW_FTR_macros[];
664 	extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
665 	unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
666 			     ftr_fixup_test_FW_FTR_macros;
667 
668 	/* The fixups have already been done for us during boot */
669 	check(memcmp(ftr_fixup_test_FW_FTR_macros,
670 		     ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
671 #endif
672 }
673 
674 static void test_lwsync_macros(void)
675 {
676 	extern u8 lwsync_fixup_test[];
677 	extern u8 end_lwsync_fixup_test[];
678 	extern u8 lwsync_fixup_test_expected_LWSYNC[];
679 	extern u8 lwsync_fixup_test_expected_SYNC[];
680 	unsigned long size = end_lwsync_fixup_test -
681 			     lwsync_fixup_test;
682 
683 	/* The fixups have already been done for us during boot */
684 	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
685 		check(memcmp(lwsync_fixup_test,
686 			     lwsync_fixup_test_expected_LWSYNC, size) == 0);
687 	} else {
688 		check(memcmp(lwsync_fixup_test,
689 			     lwsync_fixup_test_expected_SYNC, size) == 0);
690 	}
691 }
692 
693 #ifdef CONFIG_PPC64
694 static void __init test_prefix_patching(void)
695 {
696 	extern unsigned int ftr_fixup_prefix1[];
697 	extern unsigned int end_ftr_fixup_prefix1[];
698 	extern unsigned int ftr_fixup_prefix1_orig[];
699 	extern unsigned int ftr_fixup_prefix1_expected[];
700 	int size = sizeof(unsigned int) * (end_ftr_fixup_prefix1 - ftr_fixup_prefix1);
701 
702 	fixup.value = fixup.mask = 8;
703 	fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix1 + 1);
704 	fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix1 + 3);
705 	fixup.alt_start_off = fixup.alt_end_off = 0;
706 
707 	/* Sanity check */
708 	check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) == 0);
709 
710 	patch_feature_section(0, &fixup);
711 	check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_expected, size) == 0);
712 	check(memcmp(ftr_fixup_prefix1, ftr_fixup_prefix1_orig, size) != 0);
713 }
714 
715 static void __init test_prefix_alt_patching(void)
716 {
717 	extern unsigned int ftr_fixup_prefix2[];
718 	extern unsigned int end_ftr_fixup_prefix2[];
719 	extern unsigned int ftr_fixup_prefix2_orig[];
720 	extern unsigned int ftr_fixup_prefix2_expected[];
721 	extern unsigned int ftr_fixup_prefix2_alt[];
722 	int size = sizeof(unsigned int) * (end_ftr_fixup_prefix2 - ftr_fixup_prefix2);
723 
724 	fixup.value = fixup.mask = 8;
725 	fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix2 + 1);
726 	fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix2 + 3);
727 	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix2_alt);
728 	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix2_alt + 2);
729 	/* Sanity check */
730 	check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) == 0);
731 
732 	patch_feature_section(0, &fixup);
733 	check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_expected, size) == 0);
734 	check(memcmp(ftr_fixup_prefix2, ftr_fixup_prefix2_orig, size) != 0);
735 }
736 
737 static void __init test_prefix_word_alt_patching(void)
738 {
739 	extern unsigned int ftr_fixup_prefix3[];
740 	extern unsigned int end_ftr_fixup_prefix3[];
741 	extern unsigned int ftr_fixup_prefix3_orig[];
742 	extern unsigned int ftr_fixup_prefix3_expected[];
743 	extern unsigned int ftr_fixup_prefix3_alt[];
744 	int size = sizeof(unsigned int) * (end_ftr_fixup_prefix3 - ftr_fixup_prefix3);
745 
746 	fixup.value = fixup.mask = 8;
747 	fixup.start_off = calc_offset(&fixup, ftr_fixup_prefix3 + 1);
748 	fixup.end_off = calc_offset(&fixup, ftr_fixup_prefix3 + 4);
749 	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_prefix3_alt);
750 	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_prefix3_alt + 3);
751 	/* Sanity check */
752 	check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) == 0);
753 
754 	patch_feature_section(0, &fixup);
755 	check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_expected, size) == 0);
756 	patch_feature_section(0, &fixup);
757 	check(memcmp(ftr_fixup_prefix3, ftr_fixup_prefix3_orig, size) != 0);
758 }
759 #else
760 static inline void test_prefix_patching(void) {}
761 static inline void test_prefix_alt_patching(void) {}
762 static inline void test_prefix_word_alt_patching(void) {}
763 #endif /* CONFIG_PPC64 */
764 
765 static int __init test_feature_fixups(void)
766 {
767 	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
768 
769 	test_basic_patching();
770 	test_alternative_patching();
771 	test_alternative_case_too_big();
772 	test_alternative_case_too_small();
773 	test_alternative_case_with_branch();
774 	test_alternative_case_with_external_branch();
775 	test_alternative_case_with_branch_to_end();
776 	test_cpu_macros();
777 	test_fw_macros();
778 	test_lwsync_macros();
779 	test_prefix_patching();
780 	test_prefix_alt_patching();
781 	test_prefix_word_alt_patching();
782 
783 	return 0;
784 }
785 late_initcall(test_feature_fixups);
786 
787 #endif /* CONFIG_FTR_FIXUP_SELFTEST */
788