2 * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
4 * Modifications for ppc64:
5 * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
7 * Copyright 2008 Michael Ellerman, IBM Corporation.
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.
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>
24 #include <asm/sections.h>
25 #include <asm/setup.h>
26 #include <asm/firmware.h>
37 static unsigned int *calc_addr(struct fixup_entry
*fcur
, long offset
)
40 * We store the offset to the code as a negative offset from
41 * the start of the alt_entry, to support the VDSO. This
42 * routine converts that back into an actual address.
44 return (unsigned int *)((unsigned long)fcur
+ offset
);
47 static int patch_alt_instruction(unsigned int *src
, unsigned int *dest
,
48 unsigned int *alt_start
, unsigned int *alt_end
)
54 if (instr_is_relative_branch(*src
)) {
55 unsigned int *target
= (unsigned int *)branch_target(src
);
57 /* Branch within the section doesn't need translating */
58 if (target
< alt_start
|| target
>= alt_end
) {
59 instr
= translate_branch(dest
, src
);
65 patch_instruction(dest
, instr
);
70 static int patch_feature_section(unsigned long value
, struct fixup_entry
*fcur
)
72 unsigned int *start
, *end
, *alt_start
, *alt_end
, *src
, *dest
;
74 start
= calc_addr(fcur
, fcur
->start_off
);
75 end
= calc_addr(fcur
, fcur
->end_off
);
76 alt_start
= calc_addr(fcur
, fcur
->alt_start_off
);
77 alt_end
= calc_addr(fcur
, fcur
->alt_end_off
);
79 if ((alt_end
- alt_start
) > (end
- start
))
82 if ((value
& fcur
->mask
) == fcur
->value
)
88 for (; src
< alt_end
; src
++, dest
++) {
89 if (patch_alt_instruction(src
, dest
, alt_start
, alt_end
))
93 for (; dest
< end
; dest
++)
94 patch_instruction(dest
, PPC_INST_NOP
);
99 void do_feature_fixups(unsigned long value
, void *fixup_start
, void *fixup_end
)
101 struct fixup_entry
*fcur
, *fend
;
106 for (; fcur
< fend
; fcur
++) {
107 if (patch_feature_section(value
, fcur
)) {
109 printk("Unable to patch feature section at %p - %p" \
111 calc_addr(fcur
, fcur
->start_off
),
112 calc_addr(fcur
, fcur
->end_off
),
113 calc_addr(fcur
, fcur
->alt_start_off
),
114 calc_addr(fcur
, fcur
->alt_end_off
));
119 #ifdef CONFIG_PPC_BOOK3S_64
120 void do_rfi_flush_fixups(enum l1d_flush_type types
)
122 unsigned int instrs
[3], *dest
;
126 start
= PTRRELOC(&__start___rfi_flush_fixup
),
127 end
= PTRRELOC(&__stop___rfi_flush_fixup
);
129 instrs
[0] = 0x60000000; /* nop */
130 instrs
[1] = 0x60000000; /* nop */
131 instrs
[2] = 0x60000000; /* nop */
133 if (types
& L1D_FLUSH_FALLBACK
)
134 /* b .+16 to fallback flush */
135 instrs
[0] = 0x48000010;
138 if (types
& L1D_FLUSH_ORI
) {
139 instrs
[i
++] = 0x63ff0000; /* ori 31,31,0 speculation barrier */
140 instrs
[i
++] = 0x63de0000; /* ori 30,30,0 L1d flush*/
143 if (types
& L1D_FLUSH_MTTRIG
)
144 instrs
[i
++] = 0x7c12dba6; /* mtspr TRIG2,r0 (SPR #882) */
146 for (i
= 0; start
< end
; start
++, i
++) {
147 dest
= (void *)start
+ *start
;
149 pr_devel("patching dest %lx\n", (unsigned long)dest
);
151 patch_instruction(dest
, instrs
[0]);
152 patch_instruction(dest
+ 1, instrs
[1]);
153 patch_instruction(dest
+ 2, instrs
[2]);
156 printk(KERN_DEBUG
"rfi-flush: patched %d locations (%s flush)\n", i
,
157 (types
== L1D_FLUSH_NONE
) ? "no" :
158 (types
== L1D_FLUSH_FALLBACK
) ? "fallback displacement" :
159 (types
& L1D_FLUSH_ORI
) ? (types
& L1D_FLUSH_MTTRIG
)
162 (types
& L1D_FLUSH_MTTRIG
) ? "mttrig type"
165 #endif /* CONFIG_PPC_BOOK3S_64 */
167 void do_lwsync_fixups(unsigned long value
, void *fixup_start
, void *fixup_end
)
172 if (!(value
& CPU_FTR_LWSYNC
))
178 for (; start
< end
; start
++) {
179 dest
= (void *)start
+ *start
;
180 patch_instruction(dest
, PPC_INST_LWSYNC
);
184 static void do_final_fixups(void)
186 #if defined(CONFIG_PPC64) && defined(CONFIG_RELOCATABLE)
188 unsigned long length
;
190 if (PHYSICAL_START
== 0)
193 src
= (int *)(KERNELBASE
+ PHYSICAL_START
);
194 dest
= (int *)KERNELBASE
;
195 length
= (__end_interrupts
- _stext
) / sizeof(int);
198 patch_instruction(dest
, *src
);
205 static unsigned long __initdata saved_cpu_features
;
206 static unsigned int __initdata saved_mmu_features
;
208 static unsigned long __initdata saved_firmware_features
;
211 void __init
apply_feature_fixups(void)
213 struct cpu_spec
*spec
= PTRRELOC(*PTRRELOC(&cur_cpu_spec
));
215 *PTRRELOC(&saved_cpu_features
) = spec
->cpu_features
;
216 *PTRRELOC(&saved_mmu_features
) = spec
->mmu_features
;
219 * Apply the CPU-specific and firmware specific fixups to kernel text
220 * (nop out sections not relevant to this CPU or this firmware).
222 do_feature_fixups(spec
->cpu_features
,
223 PTRRELOC(&__start___ftr_fixup
),
224 PTRRELOC(&__stop___ftr_fixup
));
226 do_feature_fixups(spec
->mmu_features
,
227 PTRRELOC(&__start___mmu_ftr_fixup
),
228 PTRRELOC(&__stop___mmu_ftr_fixup
));
230 do_lwsync_fixups(spec
->cpu_features
,
231 PTRRELOC(&__start___lwsync_fixup
),
232 PTRRELOC(&__stop___lwsync_fixup
));
235 saved_firmware_features
= powerpc_firmware_features
;
236 do_feature_fixups(powerpc_firmware_features
,
237 &__start___fw_ftr_fixup
, &__stop___fw_ftr_fixup
);
242 void __init
setup_feature_keys(void)
245 * Initialise jump label. This causes all the cpu/mmu_has_feature()
246 * checks to take on their correct polarity based on the current set of
250 cpu_feature_keys_init();
251 mmu_feature_keys_init();
254 static int __init
check_features(void)
256 WARN(saved_cpu_features
!= cur_cpu_spec
->cpu_features
,
257 "CPU features changed after feature patching!\n");
258 WARN(saved_mmu_features
!= cur_cpu_spec
->mmu_features
,
259 "MMU features changed after feature patching!\n");
261 WARN(saved_firmware_features
!= powerpc_firmware_features
,
262 "Firmware features changed after feature patching!\n");
267 late_initcall(check_features
);
269 #ifdef CONFIG_FTR_FIXUP_SELFTEST
272 if (!(x)) printk("feature-fixups: test failed at line %d\n", __LINE__);
274 /* This must be after the text it fixes up, vmlinux.lds.S enforces that atm */
275 static struct fixup_entry fixup
;
277 static long calc_offset(struct fixup_entry
*entry
, unsigned int *p
)
279 return (unsigned long)p
- (unsigned long)entry
;
282 static void test_basic_patching(void)
284 extern unsigned int ftr_fixup_test1
[];
285 extern unsigned int end_ftr_fixup_test1
[];
286 extern unsigned int ftr_fixup_test1_orig
[];
287 extern unsigned int ftr_fixup_test1_expected
[];
288 int size
= end_ftr_fixup_test1
- ftr_fixup_test1
;
290 fixup
.value
= fixup
.mask
= 8;
291 fixup
.start_off
= calc_offset(&fixup
, ftr_fixup_test1
+ 1);
292 fixup
.end_off
= calc_offset(&fixup
, ftr_fixup_test1
+ 2);
293 fixup
.alt_start_off
= fixup
.alt_end_off
= 0;
296 check(memcmp(ftr_fixup_test1
, ftr_fixup_test1_orig
, size
) == 0);
298 /* Check we don't patch if the value matches */
299 patch_feature_section(8, &fixup
);
300 check(memcmp(ftr_fixup_test1
, ftr_fixup_test1_orig
, size
) == 0);
302 /* Check we do patch if the value doesn't match */
303 patch_feature_section(0, &fixup
);
304 check(memcmp(ftr_fixup_test1
, ftr_fixup_test1_expected
, size
) == 0);
306 /* Check we do patch if the mask doesn't match */
307 memcpy(ftr_fixup_test1
, ftr_fixup_test1_orig
, size
);
308 check(memcmp(ftr_fixup_test1
, ftr_fixup_test1_orig
, size
) == 0);
309 patch_feature_section(~8, &fixup
);
310 check(memcmp(ftr_fixup_test1
, ftr_fixup_test1_expected
, size
) == 0);
313 static void test_alternative_patching(void)
315 extern unsigned int ftr_fixup_test2
[];
316 extern unsigned int end_ftr_fixup_test2
[];
317 extern unsigned int ftr_fixup_test2_orig
[];
318 extern unsigned int ftr_fixup_test2_alt
[];
319 extern unsigned int ftr_fixup_test2_expected
[];
320 int size
= end_ftr_fixup_test2
- ftr_fixup_test2
;
322 fixup
.value
= fixup
.mask
= 0xF;
323 fixup
.start_off
= calc_offset(&fixup
, ftr_fixup_test2
+ 1);
324 fixup
.end_off
= calc_offset(&fixup
, ftr_fixup_test2
+ 2);
325 fixup
.alt_start_off
= calc_offset(&fixup
, ftr_fixup_test2_alt
);
326 fixup
.alt_end_off
= calc_offset(&fixup
, ftr_fixup_test2_alt
+ 1);
329 check(memcmp(ftr_fixup_test2
, ftr_fixup_test2_orig
, size
) == 0);
331 /* Check we don't patch if the value matches */
332 patch_feature_section(0xF, &fixup
);
333 check(memcmp(ftr_fixup_test2
, ftr_fixup_test2_orig
, size
) == 0);
335 /* Check we do patch if the value doesn't match */
336 patch_feature_section(0, &fixup
);
337 check(memcmp(ftr_fixup_test2
, ftr_fixup_test2_expected
, size
) == 0);
339 /* Check we do patch if the mask doesn't match */
340 memcpy(ftr_fixup_test2
, ftr_fixup_test2_orig
, size
);
341 check(memcmp(ftr_fixup_test2
, ftr_fixup_test2_orig
, size
) == 0);
342 patch_feature_section(~0xF, &fixup
);
343 check(memcmp(ftr_fixup_test2
, ftr_fixup_test2_expected
, size
) == 0);
346 static void test_alternative_case_too_big(void)
348 extern unsigned int ftr_fixup_test3
[];
349 extern unsigned int end_ftr_fixup_test3
[];
350 extern unsigned int ftr_fixup_test3_orig
[];
351 extern unsigned int ftr_fixup_test3_alt
[];
352 int size
= end_ftr_fixup_test3
- ftr_fixup_test3
;
354 fixup
.value
= fixup
.mask
= 0xC;
355 fixup
.start_off
= calc_offset(&fixup
, ftr_fixup_test3
+ 1);
356 fixup
.end_off
= calc_offset(&fixup
, ftr_fixup_test3
+ 2);
357 fixup
.alt_start_off
= calc_offset(&fixup
, ftr_fixup_test3_alt
);
358 fixup
.alt_end_off
= calc_offset(&fixup
, ftr_fixup_test3_alt
+ 2);
361 check(memcmp(ftr_fixup_test3
, ftr_fixup_test3_orig
, size
) == 0);
363 /* Expect nothing to be patched, and the error returned to us */
364 check(patch_feature_section(0xF, &fixup
) == 1);
365 check(memcmp(ftr_fixup_test3
, ftr_fixup_test3_orig
, size
) == 0);
366 check(patch_feature_section(0, &fixup
) == 1);
367 check(memcmp(ftr_fixup_test3
, ftr_fixup_test3_orig
, size
) == 0);
368 check(patch_feature_section(~0xF, &fixup
) == 1);
369 check(memcmp(ftr_fixup_test3
, ftr_fixup_test3_orig
, size
) == 0);
372 static void test_alternative_case_too_small(void)
374 extern unsigned int ftr_fixup_test4
[];
375 extern unsigned int end_ftr_fixup_test4
[];
376 extern unsigned int ftr_fixup_test4_orig
[];
377 extern unsigned int ftr_fixup_test4_alt
[];
378 extern unsigned int ftr_fixup_test4_expected
[];
379 int size
= end_ftr_fixup_test4
- ftr_fixup_test4
;
382 /* Check a high-bit flag */
383 flag
= 1UL << ((sizeof(unsigned long) - 1) * 8);
384 fixup
.value
= fixup
.mask
= flag
;
385 fixup
.start_off
= calc_offset(&fixup
, ftr_fixup_test4
+ 1);
386 fixup
.end_off
= calc_offset(&fixup
, ftr_fixup_test4
+ 5);
387 fixup
.alt_start_off
= calc_offset(&fixup
, ftr_fixup_test4_alt
);
388 fixup
.alt_end_off
= calc_offset(&fixup
, ftr_fixup_test4_alt
+ 2);
391 check(memcmp(ftr_fixup_test4
, ftr_fixup_test4_orig
, size
) == 0);
393 /* Check we don't patch if the value matches */
394 patch_feature_section(flag
, &fixup
);
395 check(memcmp(ftr_fixup_test4
, ftr_fixup_test4_orig
, size
) == 0);
397 /* Check we do patch if the value doesn't match */
398 patch_feature_section(0, &fixup
);
399 check(memcmp(ftr_fixup_test4
, ftr_fixup_test4_expected
, size
) == 0);
401 /* Check we do patch if the mask doesn't match */
402 memcpy(ftr_fixup_test4
, ftr_fixup_test4_orig
, size
);
403 check(memcmp(ftr_fixup_test4
, ftr_fixup_test4_orig
, size
) == 0);
404 patch_feature_section(~flag
, &fixup
);
405 check(memcmp(ftr_fixup_test4
, ftr_fixup_test4_expected
, size
) == 0);
408 static void test_alternative_case_with_branch(void)
410 extern unsigned int ftr_fixup_test5
[];
411 extern unsigned int end_ftr_fixup_test5
[];
412 extern unsigned int ftr_fixup_test5_expected
[];
413 int size
= end_ftr_fixup_test5
- ftr_fixup_test5
;
415 check(memcmp(ftr_fixup_test5
, ftr_fixup_test5_expected
, size
) == 0);
418 static void test_alternative_case_with_external_branch(void)
420 extern unsigned int ftr_fixup_test6
[];
421 extern unsigned int end_ftr_fixup_test6
[];
422 extern unsigned int ftr_fixup_test6_expected
[];
423 int size
= end_ftr_fixup_test6
- ftr_fixup_test6
;
425 check(memcmp(ftr_fixup_test6
, ftr_fixup_test6_expected
, size
) == 0);
428 static void test_cpu_macros(void)
430 extern u8 ftr_fixup_test_FTR_macros
[];
431 extern u8 ftr_fixup_test_FTR_macros_expected
[];
432 unsigned long size
= ftr_fixup_test_FTR_macros_expected
-
433 ftr_fixup_test_FTR_macros
;
435 /* The fixups have already been done for us during boot */
436 check(memcmp(ftr_fixup_test_FTR_macros
,
437 ftr_fixup_test_FTR_macros_expected
, size
) == 0);
440 static void test_fw_macros(void)
443 extern u8 ftr_fixup_test_FW_FTR_macros
[];
444 extern u8 ftr_fixup_test_FW_FTR_macros_expected
[];
445 unsigned long size
= ftr_fixup_test_FW_FTR_macros_expected
-
446 ftr_fixup_test_FW_FTR_macros
;
448 /* The fixups have already been done for us during boot */
449 check(memcmp(ftr_fixup_test_FW_FTR_macros
,
450 ftr_fixup_test_FW_FTR_macros_expected
, size
) == 0);
454 static void test_lwsync_macros(void)
456 extern u8 lwsync_fixup_test
[];
457 extern u8 end_lwsync_fixup_test
[];
458 extern u8 lwsync_fixup_test_expected_LWSYNC
[];
459 extern u8 lwsync_fixup_test_expected_SYNC
[];
460 unsigned long size
= end_lwsync_fixup_test
-
463 /* The fixups have already been done for us during boot */
464 if (cur_cpu_spec
->cpu_features
& CPU_FTR_LWSYNC
) {
465 check(memcmp(lwsync_fixup_test
,
466 lwsync_fixup_test_expected_LWSYNC
, size
) == 0);
468 check(memcmp(lwsync_fixup_test
,
469 lwsync_fixup_test_expected_SYNC
, size
) == 0);
473 static int __init
test_feature_fixups(void)
475 printk(KERN_DEBUG
"Running feature fixup self-tests ...\n");
477 test_basic_patching();
478 test_alternative_patching();
479 test_alternative_case_too_big();
480 test_alternative_case_too_small();
481 test_alternative_case_with_branch();
482 test_alternative_case_with_external_branch();
485 test_lwsync_macros();
489 late_initcall(test_feature_fixups
);
491 #endif /* CONFIG_FTR_FIXUP_SELFTEST */