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v4.17
 
  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
 15#include <linux/types.h>
 16#include <linux/jump_label.h>
 17#include <linux/kernel.h>
 18#include <linux/string.h>
 19#include <linux/init.h>
 20#include <linux/sched/mm.h>
 21#include <asm/cputable.h>
 22#include <asm/code-patching.h>
 23#include <asm/page.h>
 24#include <asm/sections.h>
 25#include <asm/setup.h>
 26#include <asm/security_features.h>
 27#include <asm/firmware.h>
 28
 29struct fixup_entry {
 30	unsigned long	mask;
 31	unsigned long	value;
 32	long		start_off;
 33	long		end_off;
 34	long		alt_start_off;
 35	long		alt_end_off;
 36};
 37
 38static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
 39{
 40	/*
 41	 * We store the offset to the code as a negative offset from
 42	 * the start of the alt_entry, to support the VDSO. This
 43	 * routine converts that back into an actual address.
 44	 */
 45	return (unsigned int *)((unsigned long)fcur + offset);
 46}
 47
 48static int patch_alt_instruction(unsigned int *src, unsigned int *dest,
 49				 unsigned int *alt_start, unsigned int *alt_end)
 50{
 51	unsigned int instr;
 52
 53	instr = *src;
 54
 55	if (instr_is_relative_branch(*src)) {
 56		unsigned int *target = (unsigned int *)branch_target(src);
 57
 58		/* Branch within the section doesn't need translating */
 59		if (target < alt_start || target > alt_end) {
 60			instr = translate_branch(dest, src);
 61			if (!instr)
 62				return 1;
 63		}
 64	}
 65
 66	raw_patch_instruction(dest, instr);
 67
 68	return 0;
 69}
 70
 71static int patch_feature_section(unsigned long value, struct fixup_entry *fcur)
 72{
 73	unsigned int *start, *end, *alt_start, *alt_end, *src, *dest;
 74
 75	start = calc_addr(fcur, fcur->start_off);
 76	end = calc_addr(fcur, fcur->end_off);
 77	alt_start = calc_addr(fcur, fcur->alt_start_off);
 78	alt_end = calc_addr(fcur, fcur->alt_end_off);
 79
 80	if ((alt_end - alt_start) > (end - start))
 81		return 1;
 82
 83	if ((value & fcur->mask) == fcur->value)
 84		return 0;
 85
 86	src = alt_start;
 87	dest = start;
 88
 89	for (; src < alt_end; src++, dest++) {
 90		if (patch_alt_instruction(src, dest, alt_start, alt_end))
 91			return 1;
 92	}
 93
 94	for (; dest < end; dest++)
 95		raw_patch_instruction(dest, PPC_INST_NOP);
 96
 97	return 0;
 98}
 99
100void 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
121void 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(dest, instrs[0]);
153
154		if (types & STF_BARRIER_FALLBACK)
155			patch_branch(dest + 1, (unsigned long)&stf_barrier_fallback,
156				     BRANCH_SET_LINK);
157		else
158			patch_instruction(dest + 1, instrs[1]);
159
160		patch_instruction(dest + 2, instrs[2]);
161	}
162
163	printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
164		(types == STF_BARRIER_NONE)                  ? "no" :
165		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
166		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
167		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
168		                                           : "unknown");
169}
170
171void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
172{
173	unsigned int instrs[6], *dest;
174	long *start, *end;
175	int i;
176
177	start = PTRRELOC(&__start___stf_exit_barrier_fixup),
178	end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
179
180	instrs[0] = 0x60000000; /* nop */
181	instrs[1] = 0x60000000; /* nop */
182	instrs[2] = 0x60000000; /* nop */
183	instrs[3] = 0x60000000; /* nop */
184	instrs[4] = 0x60000000; /* nop */
185	instrs[5] = 0x60000000; /* nop */
186
187	i = 0;
188	if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
189		if (cpu_has_feature(CPU_FTR_HVMODE)) {
190			instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
191			instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
192		} else {
193			instrs[i++] = 0x7db243a6; /* mtsprg 2,r13	*/
194			instrs[i++] = 0x7db142a6; /* mfsprg r13,1    */
195	        }
196		instrs[i++] = 0x7c0004ac; /* hwsync		*/
197		instrs[i++] = 0xe9ad0000; /* ld r13,0(r13)	*/
198		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
199		if (cpu_has_feature(CPU_FTR_HVMODE)) {
200			instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
201		} else {
202			instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
203		}
204	} else if (types & STF_BARRIER_EIEIO) {
205		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
206	}
207
208	for (i = 0; start < end; start++, i++) {
209		dest = (void *)start + *start;
210
211		pr_devel("patching dest %lx\n", (unsigned long)dest);
212
213		patch_instruction(dest, instrs[0]);
214		patch_instruction(dest + 1, instrs[1]);
215		patch_instruction(dest + 2, instrs[2]);
216		patch_instruction(dest + 3, instrs[3]);
217		patch_instruction(dest + 4, instrs[4]);
218		patch_instruction(dest + 5, instrs[5]);
219	}
220	printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
221		(types == STF_BARRIER_NONE)                  ? "no" :
222		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
223		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
224		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
225		                                           : "unknown");
226}
227
228
229void do_stf_barrier_fixups(enum stf_barrier_type types)
230{
231	do_stf_entry_barrier_fixups(types);
232	do_stf_exit_barrier_fixups(types);
233}
234
235void do_rfi_flush_fixups(enum l1d_flush_type types)
236{
237	unsigned int instrs[3], *dest;
238	long *start, *end;
239	int i;
240
241	start = PTRRELOC(&__start___rfi_flush_fixup),
242	end = PTRRELOC(&__stop___rfi_flush_fixup);
243
244	instrs[0] = 0x60000000; /* nop */
245	instrs[1] = 0x60000000; /* nop */
246	instrs[2] = 0x60000000; /* nop */
247
248	if (types & L1D_FLUSH_FALLBACK)
249		/* b .+16 to fallback flush */
250		instrs[0] = 0x48000010;
251
252	i = 0;
253	if (types & L1D_FLUSH_ORI) {
254		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
255		instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
256	}
257
258	if (types & L1D_FLUSH_MTTRIG)
259		instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
260
261	for (i = 0; start < end; start++, i++) {
262		dest = (void *)start + *start;
263
264		pr_devel("patching dest %lx\n", (unsigned long)dest);
265
266		patch_instruction(dest, instrs[0]);
267		patch_instruction(dest + 1, instrs[1]);
268		patch_instruction(dest + 2, instrs[2]);
269	}
270
271	printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
272		(types == L1D_FLUSH_NONE)       ? "no" :
273		(types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
274		(types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
275							? "ori+mttrig type"
276							: "ori type" :
277		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
278						: "unknown");
279}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
280#endif /* CONFIG_PPC_BOOK3S_64 */
281
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
282void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
283{
284	long *start, *end;
285	unsigned int *dest;
286
287	if (!(value & CPU_FTR_LWSYNC))
288		return ;
289
290	start = fixup_start;
291	end = fixup_end;
292
293	for (; start < end; start++) {
294		dest = (void *)start + *start;
295		raw_patch_instruction(dest, PPC_INST_LWSYNC);
296	}
297}
298
299static void do_final_fixups(void)
300{
301#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
302	int *src, *dest;
303	unsigned long length;
304
305	if (PHYSICAL_START == 0)
306		return;
307
308	src = (int *)(KERNELBASE + PHYSICAL_START);
309	dest = (int *)KERNELBASE;
310	length = (__end_interrupts - _stext) / sizeof(int);
311
312	while (length--) {
313		raw_patch_instruction(dest, *src);
314		src++;
315		dest++;
316	}
317#endif
318}
319
320static unsigned long __initdata saved_cpu_features;
321static unsigned int __initdata saved_mmu_features;
322#ifdef CONFIG_PPC64
323static unsigned long __initdata saved_firmware_features;
324#endif
325
326void __init apply_feature_fixups(void)
327{
328	struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));
329
330	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
331	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
332
333	/*
334	 * Apply the CPU-specific and firmware specific fixups to kernel text
335	 * (nop out sections not relevant to this CPU or this firmware).
336	 */
337	do_feature_fixups(spec->cpu_features,
338			  PTRRELOC(&__start___ftr_fixup),
339			  PTRRELOC(&__stop___ftr_fixup));
340
341	do_feature_fixups(spec->mmu_features,
342			  PTRRELOC(&__start___mmu_ftr_fixup),
343			  PTRRELOC(&__stop___mmu_ftr_fixup));
344
345	do_lwsync_fixups(spec->cpu_features,
346			 PTRRELOC(&__start___lwsync_fixup),
347			 PTRRELOC(&__stop___lwsync_fixup));
348
349#ifdef CONFIG_PPC64
350	saved_firmware_features = powerpc_firmware_features;
351	do_feature_fixups(powerpc_firmware_features,
352			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
353#endif
354	do_final_fixups();
355}
356
357void __init setup_feature_keys(void)
358{
359	/*
360	 * Initialise jump label. This causes all the cpu/mmu_has_feature()
361	 * checks to take on their correct polarity based on the current set of
362	 * CPU/MMU features.
363	 */
364	jump_label_init();
365	cpu_feature_keys_init();
366	mmu_feature_keys_init();
367}
368
369static int __init check_features(void)
370{
371	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
372	     "CPU features changed after feature patching!\n");
373	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
374	     "MMU features changed after feature patching!\n");
375#ifdef CONFIG_PPC64
376	WARN(saved_firmware_features != powerpc_firmware_features,
377	     "Firmware features changed after feature patching!\n");
378#endif
379
380	return 0;
381}
382late_initcall(check_features);
383
384#ifdef CONFIG_FTR_FIXUP_SELFTEST
385
386#define check(x)	\
387	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
388
389/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
390static struct fixup_entry fixup;
391
392static long calc_offset(struct fixup_entry *entry, unsigned int *p)
393{
394	return (unsigned long)p - (unsigned long)entry;
395}
396
397static void test_basic_patching(void)
398{
399	extern unsigned int ftr_fixup_test1[];
400	extern unsigned int end_ftr_fixup_test1[];
401	extern unsigned int ftr_fixup_test1_orig[];
402	extern unsigned int ftr_fixup_test1_expected[];
403	int size = end_ftr_fixup_test1 - ftr_fixup_test1;
404
405	fixup.value = fixup.mask = 8;
406	fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
407	fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
408	fixup.alt_start_off = fixup.alt_end_off = 0;
409
410	/* Sanity check */
411	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
412
413	/* Check we don't patch if the value matches */
414	patch_feature_section(8, &fixup);
415	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
416
417	/* Check we do patch if the value doesn't match */
418	patch_feature_section(0, &fixup);
419	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
420
421	/* Check we do patch if the mask doesn't match */
422	memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
423	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
424	patch_feature_section(~8, &fixup);
425	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
426}
427
428static void test_alternative_patching(void)
429{
430	extern unsigned int ftr_fixup_test2[];
431	extern unsigned int end_ftr_fixup_test2[];
432	extern unsigned int ftr_fixup_test2_orig[];
433	extern unsigned int ftr_fixup_test2_alt[];
434	extern unsigned int ftr_fixup_test2_expected[];
435	int size = end_ftr_fixup_test2 - ftr_fixup_test2;
436
437	fixup.value = fixup.mask = 0xF;
438	fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
439	fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
440	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
441	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
442
443	/* Sanity check */
444	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
445
446	/* Check we don't patch if the value matches */
447	patch_feature_section(0xF, &fixup);
448	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
449
450	/* Check we do patch if the value doesn't match */
451	patch_feature_section(0, &fixup);
452	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
453
454	/* Check we do patch if the mask doesn't match */
455	memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
456	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
457	patch_feature_section(~0xF, &fixup);
458	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
459}
460
461static void test_alternative_case_too_big(void)
462{
463	extern unsigned int ftr_fixup_test3[];
464	extern unsigned int end_ftr_fixup_test3[];
465	extern unsigned int ftr_fixup_test3_orig[];
466	extern unsigned int ftr_fixup_test3_alt[];
467	int size = end_ftr_fixup_test3 - ftr_fixup_test3;
468
469	fixup.value = fixup.mask = 0xC;
470	fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
471	fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
472	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
473	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
474
475	/* Sanity check */
476	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
477
478	/* Expect nothing to be patched, and the error returned to us */
479	check(patch_feature_section(0xF, &fixup) == 1);
480	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
481	check(patch_feature_section(0, &fixup) == 1);
482	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
483	check(patch_feature_section(~0xF, &fixup) == 1);
484	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
485}
486
487static void test_alternative_case_too_small(void)
488{
489	extern unsigned int ftr_fixup_test4[];
490	extern unsigned int end_ftr_fixup_test4[];
491	extern unsigned int ftr_fixup_test4_orig[];
492	extern unsigned int ftr_fixup_test4_alt[];
493	extern unsigned int ftr_fixup_test4_expected[];
494	int size = end_ftr_fixup_test4 - ftr_fixup_test4;
495	unsigned long flag;
496
497	/* Check a high-bit flag */
498	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
499	fixup.value = fixup.mask = flag;
500	fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
501	fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
502	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
503	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
504
505	/* Sanity check */
506	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
507
508	/* Check we don't patch if the value matches */
509	patch_feature_section(flag, &fixup);
510	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_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_test4, ftr_fixup_test4_expected, size) == 0);
515
516	/* Check we do patch if the mask doesn't match */
517	memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
518	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
519	patch_feature_section(~flag, &fixup);
520	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
521}
522
523static void test_alternative_case_with_branch(void)
524{
525	extern unsigned int ftr_fixup_test5[];
526	extern unsigned int end_ftr_fixup_test5[];
527	extern unsigned int ftr_fixup_test5_expected[];
528	int size = end_ftr_fixup_test5 - ftr_fixup_test5;
529
530	check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
531}
532
533static void test_alternative_case_with_external_branch(void)
534{
535	extern unsigned int ftr_fixup_test6[];
536	extern unsigned int end_ftr_fixup_test6[];
537	extern unsigned int ftr_fixup_test6_expected[];
538	int size = end_ftr_fixup_test6 - ftr_fixup_test6;
539
540	check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
541}
542
 
 
 
 
 
 
 
 
 
 
543static void test_cpu_macros(void)
544{
545	extern u8 ftr_fixup_test_FTR_macros[];
546	extern u8 ftr_fixup_test_FTR_macros_expected[];
547	unsigned long size = ftr_fixup_test_FTR_macros_expected -
548			     ftr_fixup_test_FTR_macros;
549
550	/* The fixups have already been done for us during boot */
551	check(memcmp(ftr_fixup_test_FTR_macros,
552		     ftr_fixup_test_FTR_macros_expected, size) == 0);
553}
554
555static void test_fw_macros(void)
556{
557#ifdef CONFIG_PPC64
558	extern u8 ftr_fixup_test_FW_FTR_macros[];
559	extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
560	unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
561			     ftr_fixup_test_FW_FTR_macros;
562
563	/* The fixups have already been done for us during boot */
564	check(memcmp(ftr_fixup_test_FW_FTR_macros,
565		     ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
566#endif
567}
568
569static void test_lwsync_macros(void)
570{
571	extern u8 lwsync_fixup_test[];
572	extern u8 end_lwsync_fixup_test[];
573	extern u8 lwsync_fixup_test_expected_LWSYNC[];
574	extern u8 lwsync_fixup_test_expected_SYNC[];
575	unsigned long size = end_lwsync_fixup_test -
576			     lwsync_fixup_test;
577
578	/* The fixups have already been done for us during boot */
579	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
580		check(memcmp(lwsync_fixup_test,
581			     lwsync_fixup_test_expected_LWSYNC, size) == 0);
582	} else {
583		check(memcmp(lwsync_fixup_test,
584			     lwsync_fixup_test_expected_SYNC, size) == 0);
585	}
586}
587
588static int __init test_feature_fixups(void)
589{
590	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
591
592	test_basic_patching();
593	test_alternative_patching();
594	test_alternative_case_too_big();
595	test_alternative_case_too_small();
596	test_alternative_case_with_branch();
597	test_alternative_case_with_external_branch();
 
598	test_cpu_macros();
599	test_fw_macros();
600	test_lwsync_macros();
601
602	return 0;
603}
604late_initcall(test_feature_fixups);
605
606#endif /* CONFIG_FTR_FIXUP_SELFTEST */
v5.4
  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
 25struct fixup_entry {
 26	unsigned long	mask;
 27	unsigned long	value;
 28	long		start_off;
 29	long		end_off;
 30	long		alt_start_off;
 31	long		alt_end_off;
 32};
 33
 34static unsigned int *calc_addr(struct fixup_entry *fcur, long offset)
 35{
 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
 44static 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	raw_patch_instruction(dest, instr);
 63
 64	return 0;
 65}
 66
 67static 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;
 78
 79	if ((value & fcur->mask) == fcur->value)
 80		return 0;
 81
 82	src = alt_start;
 83	dest = start;
 84
 85	for (; src < alt_end; src++, dest++) {
 86		if (patch_alt_instruction(src, dest, alt_start, alt_end))
 87			return 1;
 88	}
 89
 90	for (; dest < end; dest++)
 91		raw_patch_instruction(dest, PPC_INST_NOP);
 92
 93	return 0;
 94}
 95
 96void 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
103	for (; fcur < fend; fcur++) {
104		if (patch_feature_section(value, fcur)) {
105			WARN_ON(1);
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	}
114}
115
116#ifdef CONFIG_PPC_BOOK3S_64
117static void do_stf_entry_barrier_fixups(enum stf_barrier_type types)
118{
119	unsigned int instrs[3], *dest;
120	long *start, *end;
121	int i;
122
123	start = PTRRELOC(&__start___stf_entry_barrier_fixup),
124	end = PTRRELOC(&__stop___stf_entry_barrier_fixup);
125
126	instrs[0] = 0x60000000; /* nop */
127	instrs[1] = 0x60000000; /* nop */
128	instrs[2] = 0x60000000; /* nop */
129
130	i = 0;
131	if (types & STF_BARRIER_FALLBACK) {
132		instrs[i++] = 0x7d4802a6; /* mflr r10		*/
133		instrs[i++] = 0x60000000; /* branch patched below */
134		instrs[i++] = 0x7d4803a6; /* mtlr r10		*/
135	} else if (types & STF_BARRIER_EIEIO) {
136		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
137	} else if (types & STF_BARRIER_SYNC_ORI) {
138		instrs[i++] = 0x7c0004ac; /* hwsync		*/
139		instrs[i++] = 0xe94d0000; /* ld r10,0(r13)	*/
140		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
141	}
142
143	for (i = 0; start < end; start++, i++) {
144		dest = (void *)start + *start;
145
146		pr_devel("patching dest %lx\n", (unsigned long)dest);
147
148		patch_instruction(dest, instrs[0]);
149
150		if (types & STF_BARRIER_FALLBACK)
151			patch_branch(dest + 1, (unsigned long)&stf_barrier_fallback,
152				     BRANCH_SET_LINK);
153		else
154			patch_instruction(dest + 1, instrs[1]);
155
156		patch_instruction(dest + 2, instrs[2]);
157	}
158
159	printk(KERN_DEBUG "stf-barrier: patched %d entry locations (%s barrier)\n", i,
160		(types == STF_BARRIER_NONE)                  ? "no" :
161		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
162		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
163		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
164		                                           : "unknown");
165}
166
167static void do_stf_exit_barrier_fixups(enum stf_barrier_type types)
168{
169	unsigned int instrs[6], *dest;
170	long *start, *end;
171	int i;
172
173	start = PTRRELOC(&__start___stf_exit_barrier_fixup),
174	end = PTRRELOC(&__stop___stf_exit_barrier_fixup);
175
176	instrs[0] = 0x60000000; /* nop */
177	instrs[1] = 0x60000000; /* nop */
178	instrs[2] = 0x60000000; /* nop */
179	instrs[3] = 0x60000000; /* nop */
180	instrs[4] = 0x60000000; /* nop */
181	instrs[5] = 0x60000000; /* nop */
182
183	i = 0;
184	if (types & STF_BARRIER_FALLBACK || types & STF_BARRIER_SYNC_ORI) {
185		if (cpu_has_feature(CPU_FTR_HVMODE)) {
186			instrs[i++] = 0x7db14ba6; /* mtspr 0x131, r13 (HSPRG1) */
187			instrs[i++] = 0x7db04aa6; /* mfspr r13, 0x130 (HSPRG0) */
188		} else {
189			instrs[i++] = 0x7db243a6; /* mtsprg 2,r13	*/
190			instrs[i++] = 0x7db142a6; /* mfsprg r13,1    */
191	        }
192		instrs[i++] = 0x7c0004ac; /* hwsync		*/
193		instrs[i++] = 0xe9ad0000; /* ld r13,0(r13)	*/
194		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
195		if (cpu_has_feature(CPU_FTR_HVMODE)) {
196			instrs[i++] = 0x7db14aa6; /* mfspr r13, 0x131 (HSPRG1) */
197		} else {
198			instrs[i++] = 0x7db242a6; /* mfsprg r13,2 */
199		}
200	} else if (types & STF_BARRIER_EIEIO) {
201		instrs[i++] = 0x7e0006ac; /* eieio + bit 6 hint */
202	}
203
204	for (i = 0; start < end; start++, i++) {
205		dest = (void *)start + *start;
206
207		pr_devel("patching dest %lx\n", (unsigned long)dest);
208
209		patch_instruction(dest, instrs[0]);
210		patch_instruction(dest + 1, instrs[1]);
211		patch_instruction(dest + 2, instrs[2]);
212		patch_instruction(dest + 3, instrs[3]);
213		patch_instruction(dest + 4, instrs[4]);
214		patch_instruction(dest + 5, instrs[5]);
215	}
216	printk(KERN_DEBUG "stf-barrier: patched %d exit locations (%s barrier)\n", i,
217		(types == STF_BARRIER_NONE)                  ? "no" :
218		(types == STF_BARRIER_FALLBACK)              ? "fallback" :
219		(types == STF_BARRIER_EIEIO)                 ? "eieio" :
220		(types == (STF_BARRIER_SYNC_ORI))            ? "hwsync"
221		                                           : "unknown");
222}
223
224
225void do_stf_barrier_fixups(enum stf_barrier_type types)
226{
227	do_stf_entry_barrier_fixups(types);
228	do_stf_exit_barrier_fixups(types);
229}
230
231void do_rfi_flush_fixups(enum l1d_flush_type types)
232{
233	unsigned int instrs[3], *dest;
234	long *start, *end;
235	int i;
236
237	start = PTRRELOC(&__start___rfi_flush_fixup),
238	end = PTRRELOC(&__stop___rfi_flush_fixup);
239
240	instrs[0] = 0x60000000; /* nop */
241	instrs[1] = 0x60000000; /* nop */
242	instrs[2] = 0x60000000; /* nop */
243
244	if (types & L1D_FLUSH_FALLBACK)
245		/* b .+16 to fallback flush */
246		instrs[0] = 0x48000010;
247
248	i = 0;
249	if (types & L1D_FLUSH_ORI) {
250		instrs[i++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
251		instrs[i++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
252	}
253
254	if (types & L1D_FLUSH_MTTRIG)
255		instrs[i++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
256
257	for (i = 0; start < end; start++, i++) {
258		dest = (void *)start + *start;
259
260		pr_devel("patching dest %lx\n", (unsigned long)dest);
261
262		patch_instruction(dest, instrs[0]);
263		patch_instruction(dest + 1, instrs[1]);
264		patch_instruction(dest + 2, instrs[2]);
265	}
266
267	printk(KERN_DEBUG "rfi-flush: patched %d locations (%s flush)\n", i,
268		(types == L1D_FLUSH_NONE)       ? "no" :
269		(types == L1D_FLUSH_FALLBACK)   ? "fallback displacement" :
270		(types &  L1D_FLUSH_ORI)        ? (types & L1D_FLUSH_MTTRIG)
271							? "ori+mttrig type"
272							: "ori type" :
273		(types &  L1D_FLUSH_MTTRIG)     ? "mttrig type"
274						: "unknown");
275}
276
277void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
278{
279	unsigned int instr, *dest;
280	long *start, *end;
281	int i;
282
283	start = fixup_start;
284	end = fixup_end;
285
286	instr = 0x60000000; /* nop */
287
288	if (enable) {
289		pr_info("barrier-nospec: using ORI speculation barrier\n");
290		instr = 0x63ff0000; /* ori 31,31,0 speculation barrier */
291	}
292
293	for (i = 0; start < end; start++, i++) {
294		dest = (void *)start + *start;
295
296		pr_devel("patching dest %lx\n", (unsigned long)dest);
297		patch_instruction(dest, instr);
298	}
299
300	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
301}
302
303#endif /* CONFIG_PPC_BOOK3S_64 */
304
305#ifdef CONFIG_PPC_BARRIER_NOSPEC
306void do_barrier_nospec_fixups(bool enable)
307{
308	void *start, *end;
309
310	start = PTRRELOC(&__start___barrier_nospec_fixup),
311	end = PTRRELOC(&__stop___barrier_nospec_fixup);
312
313	do_barrier_nospec_fixups_range(enable, start, end);
314}
315#endif /* CONFIG_PPC_BARRIER_NOSPEC */
316
317#ifdef CONFIG_PPC_FSL_BOOK3E
318void do_barrier_nospec_fixups_range(bool enable, void *fixup_start, void *fixup_end)
319{
320	unsigned int instr[2], *dest;
321	long *start, *end;
322	int i;
323
324	start = fixup_start;
325	end = fixup_end;
326
327	instr[0] = PPC_INST_NOP;
328	instr[1] = PPC_INST_NOP;
329
330	if (enable) {
331		pr_info("barrier-nospec: using isync; sync as speculation barrier\n");
332		instr[0] = PPC_INST_ISYNC;
333		instr[1] = PPC_INST_SYNC;
334	}
335
336	for (i = 0; start < end; start++, i++) {
337		dest = (void *)start + *start;
338
339		pr_devel("patching dest %lx\n", (unsigned long)dest);
340		patch_instruction(dest, instr[0]);
341		patch_instruction(dest + 1, instr[1]);
342	}
343
344	printk(KERN_DEBUG "barrier-nospec: patched %d locations\n", i);
345}
346
347static void patch_btb_flush_section(long *curr)
348{
349	unsigned int *start, *end;
350
351	start = (void *)curr + *curr;
352	end = (void *)curr + *(curr + 1);
353	for (; start < end; start++) {
354		pr_devel("patching dest %lx\n", (unsigned long)start);
355		patch_instruction(start, PPC_INST_NOP);
356	}
357}
358
359void do_btb_flush_fixups(void)
360{
361	long *start, *end;
362
363	start = PTRRELOC(&__start__btb_flush_fixup);
364	end = PTRRELOC(&__stop__btb_flush_fixup);
365
366	for (; start < end; start += 2)
367		patch_btb_flush_section(start);
368}
369#endif /* CONFIG_PPC_FSL_BOOK3E */
370
371void do_lwsync_fixups(unsigned long value, void *fixup_start, void *fixup_end)
372{
373	long *start, *end;
374	unsigned int *dest;
375
376	if (!(value & CPU_FTR_LWSYNC))
377		return ;
378
379	start = fixup_start;
380	end = fixup_end;
381
382	for (; start < end; start++) {
383		dest = (void *)start + *start;
384		raw_patch_instruction(dest, PPC_INST_LWSYNC);
385	}
386}
387
388static void do_final_fixups(void)
389{
390#if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
391	int *src, *dest;
392	unsigned long length;
393
394	if (PHYSICAL_START == 0)
395		return;
396
397	src = (int *)(KERNELBASE + PHYSICAL_START);
398	dest = (int *)KERNELBASE;
399	length = (__end_interrupts - _stext) / sizeof(int);
400
401	while (length--) {
402		raw_patch_instruction(dest, *src);
403		src++;
404		dest++;
405	}
406#endif
407}
408
409static unsigned long __initdata saved_cpu_features;
410static unsigned int __initdata saved_mmu_features;
411#ifdef CONFIG_PPC64
412static unsigned long __initdata saved_firmware_features;
413#endif
414
415void __init apply_feature_fixups(void)
416{
417	struct cpu_spec *spec = PTRRELOC(*PTRRELOC(&cur_cpu_spec));
418
419	*PTRRELOC(&saved_cpu_features) = spec->cpu_features;
420	*PTRRELOC(&saved_mmu_features) = spec->mmu_features;
421
422	/*
423	 * Apply the CPU-specific and firmware specific fixups to kernel text
424	 * (nop out sections not relevant to this CPU or this firmware).
425	 */
426	do_feature_fixups(spec->cpu_features,
427			  PTRRELOC(&__start___ftr_fixup),
428			  PTRRELOC(&__stop___ftr_fixup));
429
430	do_feature_fixups(spec->mmu_features,
431			  PTRRELOC(&__start___mmu_ftr_fixup),
432			  PTRRELOC(&__stop___mmu_ftr_fixup));
433
434	do_lwsync_fixups(spec->cpu_features,
435			 PTRRELOC(&__start___lwsync_fixup),
436			 PTRRELOC(&__stop___lwsync_fixup));
437
438#ifdef CONFIG_PPC64
439	saved_firmware_features = powerpc_firmware_features;
440	do_feature_fixups(powerpc_firmware_features,
441			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
442#endif
443	do_final_fixups();
444}
445
446void __init setup_feature_keys(void)
447{
448	/*
449	 * Initialise jump label. This causes all the cpu/mmu_has_feature()
450	 * checks to take on their correct polarity based on the current set of
451	 * CPU/MMU features.
452	 */
453	jump_label_init();
454	cpu_feature_keys_init();
455	mmu_feature_keys_init();
456}
457
458static int __init check_features(void)
459{
460	WARN(saved_cpu_features != cur_cpu_spec->cpu_features,
461	     "CPU features changed after feature patching!\n");
462	WARN(saved_mmu_features != cur_cpu_spec->mmu_features,
463	     "MMU features changed after feature patching!\n");
464#ifdef CONFIG_PPC64
465	WARN(saved_firmware_features != powerpc_firmware_features,
466	     "Firmware features changed after feature patching!\n");
467#endif
468
469	return 0;
470}
471late_initcall(check_features);
472
473#ifdef CONFIG_FTR_FIXUP_SELFTEST
474
475#define check(x)	\
476	if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
477
478/* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
479static struct fixup_entry fixup;
480
481static long calc_offset(struct fixup_entry *entry, unsigned int *p)
482{
483	return (unsigned long)p - (unsigned long)entry;
484}
485
486static void test_basic_patching(void)
487{
488	extern unsigned int ftr_fixup_test1[];
489	extern unsigned int end_ftr_fixup_test1[];
490	extern unsigned int ftr_fixup_test1_orig[];
491	extern unsigned int ftr_fixup_test1_expected[];
492	int size = 4 * (end_ftr_fixup_test1 - ftr_fixup_test1);
493
494	fixup.value = fixup.mask = 8;
495	fixup.start_off = calc_offset(&fixup, ftr_fixup_test1 + 1);
496	fixup.end_off = calc_offset(&fixup, ftr_fixup_test1 + 2);
497	fixup.alt_start_off = fixup.alt_end_off = 0;
498
499	/* Sanity check */
500	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
501
502	/* Check we don't patch if the value matches */
503	patch_feature_section(8, &fixup);
504	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
505
506	/* Check we do patch if the value doesn't match */
507	patch_feature_section(0, &fixup);
508	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
509
510	/* Check we do patch if the mask doesn't match */
511	memcpy(ftr_fixup_test1, ftr_fixup_test1_orig, size);
512	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_orig, size) == 0);
513	patch_feature_section(~8, &fixup);
514	check(memcmp(ftr_fixup_test1, ftr_fixup_test1_expected, size) == 0);
515}
516
517static void test_alternative_patching(void)
518{
519	extern unsigned int ftr_fixup_test2[];
520	extern unsigned int end_ftr_fixup_test2[];
521	extern unsigned int ftr_fixup_test2_orig[];
522	extern unsigned int ftr_fixup_test2_alt[];
523	extern unsigned int ftr_fixup_test2_expected[];
524	int size = 4 * (end_ftr_fixup_test2 - ftr_fixup_test2);
525
526	fixup.value = fixup.mask = 0xF;
527	fixup.start_off = calc_offset(&fixup, ftr_fixup_test2 + 1);
528	fixup.end_off = calc_offset(&fixup, ftr_fixup_test2 + 2);
529	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test2_alt);
530	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test2_alt + 1);
531
532	/* Sanity check */
533	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
534
535	/* Check we don't patch if the value matches */
536	patch_feature_section(0xF, &fixup);
537	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
538
539	/* Check we do patch if the value doesn't match */
540	patch_feature_section(0, &fixup);
541	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
542
543	/* Check we do patch if the mask doesn't match */
544	memcpy(ftr_fixup_test2, ftr_fixup_test2_orig, size);
545	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_orig, size) == 0);
546	patch_feature_section(~0xF, &fixup);
547	check(memcmp(ftr_fixup_test2, ftr_fixup_test2_expected, size) == 0);
548}
549
550static void test_alternative_case_too_big(void)
551{
552	extern unsigned int ftr_fixup_test3[];
553	extern unsigned int end_ftr_fixup_test3[];
554	extern unsigned int ftr_fixup_test3_orig[];
555	extern unsigned int ftr_fixup_test3_alt[];
556	int size = 4 * (end_ftr_fixup_test3 - ftr_fixup_test3);
557
558	fixup.value = fixup.mask = 0xC;
559	fixup.start_off = calc_offset(&fixup, ftr_fixup_test3 + 1);
560	fixup.end_off = calc_offset(&fixup, ftr_fixup_test3 + 2);
561	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test3_alt);
562	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test3_alt + 2);
563
564	/* Sanity check */
565	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
566
567	/* Expect nothing to be patched, and the error returned to us */
568	check(patch_feature_section(0xF, &fixup) == 1);
569	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
570	check(patch_feature_section(0, &fixup) == 1);
571	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
572	check(patch_feature_section(~0xF, &fixup) == 1);
573	check(memcmp(ftr_fixup_test3, ftr_fixup_test3_orig, size) == 0);
574}
575
576static void test_alternative_case_too_small(void)
577{
578	extern unsigned int ftr_fixup_test4[];
579	extern unsigned int end_ftr_fixup_test4[];
580	extern unsigned int ftr_fixup_test4_orig[];
581	extern unsigned int ftr_fixup_test4_alt[];
582	extern unsigned int ftr_fixup_test4_expected[];
583	int size = 4 * (end_ftr_fixup_test4 - ftr_fixup_test4);
584	unsigned long flag;
585
586	/* Check a high-bit flag */
587	flag = 1UL << ((sizeof(unsigned long) - 1) * 8);
588	fixup.value = fixup.mask = flag;
589	fixup.start_off = calc_offset(&fixup, ftr_fixup_test4 + 1);
590	fixup.end_off = calc_offset(&fixup, ftr_fixup_test4 + 5);
591	fixup.alt_start_off = calc_offset(&fixup, ftr_fixup_test4_alt);
592	fixup.alt_end_off = calc_offset(&fixup, ftr_fixup_test4_alt + 2);
593
594	/* Sanity check */
595	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
596
597	/* Check we don't patch if the value matches */
598	patch_feature_section(flag, &fixup);
599	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
600
601	/* Check we do patch if the value doesn't match */
602	patch_feature_section(0, &fixup);
603	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
604
605	/* Check we do patch if the mask doesn't match */
606	memcpy(ftr_fixup_test4, ftr_fixup_test4_orig, size);
607	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_orig, size) == 0);
608	patch_feature_section(~flag, &fixup);
609	check(memcmp(ftr_fixup_test4, ftr_fixup_test4_expected, size) == 0);
610}
611
612static void test_alternative_case_with_branch(void)
613{
614	extern unsigned int ftr_fixup_test5[];
615	extern unsigned int end_ftr_fixup_test5[];
616	extern unsigned int ftr_fixup_test5_expected[];
617	int size = 4 * (end_ftr_fixup_test5 - ftr_fixup_test5);
618
619	check(memcmp(ftr_fixup_test5, ftr_fixup_test5_expected, size) == 0);
620}
621
622static void test_alternative_case_with_external_branch(void)
623{
624	extern unsigned int ftr_fixup_test6[];
625	extern unsigned int end_ftr_fixup_test6[];
626	extern unsigned int ftr_fixup_test6_expected[];
627	int size = 4 * (end_ftr_fixup_test6 - ftr_fixup_test6);
628
629	check(memcmp(ftr_fixup_test6, ftr_fixup_test6_expected, size) == 0);
630}
631
632static void test_alternative_case_with_branch_to_end(void)
633{
634	extern unsigned int ftr_fixup_test7[];
635	extern unsigned int end_ftr_fixup_test7[];
636	extern unsigned int ftr_fixup_test7_expected[];
637	int size = 4 * (end_ftr_fixup_test7 - ftr_fixup_test7);
638
639	check(memcmp(ftr_fixup_test7, ftr_fixup_test7_expected, size) == 0);
640}
641
642static void test_cpu_macros(void)
643{
644	extern u8 ftr_fixup_test_FTR_macros[];
645	extern u8 ftr_fixup_test_FTR_macros_expected[];
646	unsigned long size = ftr_fixup_test_FTR_macros_expected -
647			     ftr_fixup_test_FTR_macros;
648
649	/* The fixups have already been done for us during boot */
650	check(memcmp(ftr_fixup_test_FTR_macros,
651		     ftr_fixup_test_FTR_macros_expected, size) == 0);
652}
653
654static void test_fw_macros(void)
655{
656#ifdef CONFIG_PPC64
657	extern u8 ftr_fixup_test_FW_FTR_macros[];
658	extern u8 ftr_fixup_test_FW_FTR_macros_expected[];
659	unsigned long size = ftr_fixup_test_FW_FTR_macros_expected -
660			     ftr_fixup_test_FW_FTR_macros;
661
662	/* The fixups have already been done for us during boot */
663	check(memcmp(ftr_fixup_test_FW_FTR_macros,
664		     ftr_fixup_test_FW_FTR_macros_expected, size) == 0);
665#endif
666}
667
668static void test_lwsync_macros(void)
669{
670	extern u8 lwsync_fixup_test[];
671	extern u8 end_lwsync_fixup_test[];
672	extern u8 lwsync_fixup_test_expected_LWSYNC[];
673	extern u8 lwsync_fixup_test_expected_SYNC[];
674	unsigned long size = end_lwsync_fixup_test -
675			     lwsync_fixup_test;
676
677	/* The fixups have already been done for us during boot */
678	if (cur_cpu_spec->cpu_features & CPU_FTR_LWSYNC) {
679		check(memcmp(lwsync_fixup_test,
680			     lwsync_fixup_test_expected_LWSYNC, size) == 0);
681	} else {
682		check(memcmp(lwsync_fixup_test,
683			     lwsync_fixup_test_expected_SYNC, size) == 0);
684	}
685}
686
687static int __init test_feature_fixups(void)
688{
689	printk(KERN_DEBUG "Running feature fixup self-tests ...\n");
690
691	test_basic_patching();
692	test_alternative_patching();
693	test_alternative_case_too_big();
694	test_alternative_case_too_small();
695	test_alternative_case_with_branch();
696	test_alternative_case_with_external_branch();
697	test_alternative_case_with_branch_to_end();
698	test_cpu_macros();
699	test_fw_macros();
700	test_lwsync_macros();
701
702	return 0;
703}
704late_initcall(test_feature_fixups);
705
706#endif /* CONFIG_FTR_FIXUP_SELFTEST */