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Linux 3.8-rc7
[cris-mirror.git] / arch / x86 / kernel / cpu / mtrr / cleanup.c
blob35ffda5d0727d19b11cccccdde0e0d461b9e15ee
1 /*
2 * MTRR (Memory Type Range Register) cleanup
3 *
4 * Copyright (C) 2009 Yinghai Lu
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/pci.h>
23 #include <linux/smp.h>
24 #include <linux/cpu.h>
25 #include <linux/mutex.h>
26 #include <linux/uaccess.h>
27 #include <linux/kvm_para.h>
28 #include <linux/range.h>
29
30 #include <asm/processor.h>
31 #include <asm/e820.h>
32 #include <asm/mtrr.h>
33 #include <asm/msr.h>
34
35 #include "mtrr.h"
36
37 struct var_mtrr_range_state {
38 unsigned long base_pfn;
39 unsigned long size_pfn;
40 mtrr_type type;
41 };
42
43 struct var_mtrr_state {
44 unsigned long range_startk;
45 unsigned long range_sizek;
46 unsigned long chunk_sizek;
47 unsigned long gran_sizek;
48 unsigned int reg;
49 };
50
51 /* Should be related to MTRR_VAR_RANGES nums */
52 #define RANGE_NUM 256
53
54 static struct range __initdata range[RANGE_NUM];
55 static int __initdata nr_range;
56
57 static struct var_mtrr_range_state __initdata range_state[RANGE_NUM];
58
59 static int __initdata debug_print;
60 #define Dprintk(x...) do { if (debug_print) printk(KERN_DEBUG x); } while (0)
61
62 #define BIOS_BUG_MSG KERN_WARNING \
63 "WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n"
64
65 static int __init
66 x86_get_mtrr_mem_range(struct range *range, int nr_range,
67 unsigned long extra_remove_base,
68 unsigned long extra_remove_size)
69 {
70 unsigned long base, size;
71 mtrr_type type;
72 int i;
73
74 for (i = 0; i < num_var_ranges; i++) {
75 type = range_state[i].type;
76 if (type != MTRR_TYPE_WRBACK)
77 continue;
78 base = range_state[i].base_pfn;
79 size = range_state[i].size_pfn;
80 nr_range = add_range_with_merge(range, RANGE_NUM, nr_range,
81 base, base + size);
82 }
83 if (debug_print) {
84 printk(KERN_DEBUG "After WB checking\n");
85 for (i = 0; i < nr_range; i++)
86 printk(KERN_DEBUG "MTRR MAP PFN: %016llx - %016llx\n",
87 range[i].start, range[i].end);
88 }
89
90 /* Take out UC ranges: */
91 for (i = 0; i < num_var_ranges; i++) {
92 type = range_state[i].type;
93 if (type != MTRR_TYPE_UNCACHABLE &&
94 type != MTRR_TYPE_WRPROT)
95 continue;
96 size = range_state[i].size_pfn;
97 if (!size)
98 continue;
99 base = range_state[i].base_pfn;
100 if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed &&
101 (mtrr_state.enabled & 1)) {
102 /* Var MTRR contains UC entry below 1M? Skip it: */
103 printk(BIOS_BUG_MSG, i);
104 if (base + size <= (1<<(20-PAGE_SHIFT)))
105 continue;
106 size -= (1<<(20-PAGE_SHIFT)) - base;
107 base = 1<<(20-PAGE_SHIFT);
108 }
109 subtract_range(range, RANGE_NUM, base, base + size);
110 }
111 if (extra_remove_size)
112 subtract_range(range, RANGE_NUM, extra_remove_base,
113 extra_remove_base + extra_remove_size);
114
115 if (debug_print) {
116 printk(KERN_DEBUG "After UC checking\n");
117 for (i = 0; i < RANGE_NUM; i++) {
118 if (!range[i].end)
119 continue;
120 printk(KERN_DEBUG "MTRR MAP PFN: %016llx - %016llx\n",
121 range[i].start, range[i].end);
122 }
123 }
124
125 /* sort the ranges */
126 nr_range = clean_sort_range(range, RANGE_NUM);
127 if (debug_print) {
128 printk(KERN_DEBUG "After sorting\n");
129 for (i = 0; i < nr_range; i++)
130 printk(KERN_DEBUG "MTRR MAP PFN: %016llx - %016llx\n",
131 range[i].start, range[i].end);
132 }
133
134 return nr_range;
135 }
136
137 #ifdef CONFIG_MTRR_SANITIZER
138
139 static unsigned long __init sum_ranges(struct range *range, int nr_range)
140 {
141 unsigned long sum = 0;
142 int i;
143
144 for (i = 0; i < nr_range; i++)
145 sum += range[i].end - range[i].start;
146
147 return sum;
148 }
149
150 static int enable_mtrr_cleanup __initdata =
151 CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
152
153 static int __init disable_mtrr_cleanup_setup(char *str)
154 {
155 enable_mtrr_cleanup = 0;
156 return 0;
157 }
158 early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
159
160 static int __init enable_mtrr_cleanup_setup(char *str)
161 {
162 enable_mtrr_cleanup = 1;
163 return 0;
164 }
165 early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup);
166
167 static int __init mtrr_cleanup_debug_setup(char *str)
168 {
169 debug_print = 1;
170 return 0;
171 }
172 early_param("mtrr_cleanup_debug", mtrr_cleanup_debug_setup);
173
174 static void __init
175 set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
176 unsigned char type, unsigned int address_bits)
177 {
178 u32 base_lo, base_hi, mask_lo, mask_hi;
179 u64 base, mask;
180
181 if (!sizek) {
182 fill_mtrr_var_range(reg, 0, 0, 0, 0);
183 return;
184 }
185
186 mask = (1ULL << address_bits) - 1;
187 mask &= ~((((u64)sizek) << 10) - 1);
188
189 base = ((u64)basek) << 10;
190
191 base |= type;
192 mask |= 0x800;
193
194 base_lo = base & ((1ULL<<32) - 1);
195 base_hi = base >> 32;
196
197 mask_lo = mask & ((1ULL<<32) - 1);
198 mask_hi = mask >> 32;
199
200 fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
201 }
202
203 static void __init
204 save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
205 unsigned char type)
206 {
207 range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
208 range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
209 range_state[reg].type = type;
210 }
211
212 static void __init set_var_mtrr_all(unsigned int address_bits)
213 {
214 unsigned long basek, sizek;
215 unsigned char type;
216 unsigned int reg;
217
218 for (reg = 0; reg < num_var_ranges; reg++) {
219 basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
220 sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
221 type = range_state[reg].type;
222
223 set_var_mtrr(reg, basek, sizek, type, address_bits);
224 }
225 }
226
227 static unsigned long to_size_factor(unsigned long sizek, char *factorp)
228 {
229 unsigned long base = sizek;
230 char factor;
231
232 if (base & ((1<<10) - 1)) {
233 /* Not MB-aligned: */
234 factor = 'K';
235 } else if (base & ((1<<20) - 1)) {
236 factor = 'M';
237 base >>= 10;
238 } else {
239 factor = 'G';
240 base >>= 20;
241 }
242
243 *factorp = factor;
244
245 return base;
246 }
247
248 static unsigned int __init
249 range_to_mtrr(unsigned int reg, unsigned long range_startk,
250 unsigned long range_sizek, unsigned char type)
251 {
252 if (!range_sizek || (reg >= num_var_ranges))
253 return reg;
254
255 while (range_sizek) {
256 unsigned long max_align, align;
257 unsigned long sizek;
258
259 /* Compute the maximum size with which we can make a range: */
260 if (range_startk)
261 max_align = __ffs(range_startk);
262 else
263 max_align = BITS_PER_LONG - 1;
264
265 align = __fls(range_sizek);
266 if (align > max_align)
267 align = max_align;
268
269 sizek = 1UL << align;
270 if (debug_print) {
271 char start_factor = 'K', size_factor = 'K';
272 unsigned long start_base, size_base;
273
274 start_base = to_size_factor(range_startk, &start_factor);
275 size_base = to_size_factor(sizek, &size_factor);
276
277 Dprintk("Setting variable MTRR %d, "
278 "base: %ld%cB, range: %ld%cB, type %s\n",
279 reg, start_base, start_factor,
280 size_base, size_factor,
281 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
282 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")
283 );
284 }
285 save_var_mtrr(reg++, range_startk, sizek, type);
286 range_startk += sizek;
287 range_sizek -= sizek;
288 if (reg >= num_var_ranges)
289 break;
290 }
291 return reg;
292 }
293
294 static unsigned __init
295 range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
296 unsigned long sizek)
297 {
298 unsigned long hole_basek, hole_sizek;
299 unsigned long second_basek, second_sizek;
300 unsigned long range0_basek, range0_sizek;
301 unsigned long range_basek, range_sizek;
302 unsigned long chunk_sizek;
303 unsigned long gran_sizek;
304
305 hole_basek = 0;
306 hole_sizek = 0;
307 second_basek = 0;
308 second_sizek = 0;
309 chunk_sizek = state->chunk_sizek;
310 gran_sizek = state->gran_sizek;
311
312 /* Align with gran size, prevent small block used up MTRRs: */
313 range_basek = ALIGN(state->range_startk, gran_sizek);
314 if ((range_basek > basek) && basek)
315 return second_sizek;
316
317 state->range_sizek -= (range_basek - state->range_startk);
318 range_sizek = ALIGN(state->range_sizek, gran_sizek);
319
320 while (range_sizek > state->range_sizek) {
321 range_sizek -= gran_sizek;
322 if (!range_sizek)
323 return 0;
324 }
325 state->range_sizek = range_sizek;
326
327 /* Try to append some small hole: */
328 range0_basek = state->range_startk;
329 range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
330
331 /* No increase: */
332 if (range0_sizek == state->range_sizek) {
333 Dprintk("rangeX: %016lx - %016lx\n",
334 range0_basek<<10,
335 (range0_basek + state->range_sizek)<<10);
336 state->reg = range_to_mtrr(state->reg, range0_basek,
337 state->range_sizek, MTRR_TYPE_WRBACK);
338 return 0;
339 }
340
341 /* Only cut back when it is not the last: */
342 if (sizek) {
343 while (range0_basek + range0_sizek > (basek + sizek)) {
344 if (range0_sizek >= chunk_sizek)
345 range0_sizek -= chunk_sizek;
346 else
347 range0_sizek = 0;
348
349 if (!range0_sizek)
350 break;
351 }
352 }
353
354 second_try:
355 range_basek = range0_basek + range0_sizek;
356
357 /* One hole in the middle: */
358 if (range_basek > basek && range_basek <= (basek + sizek))
359 second_sizek = range_basek - basek;
360
361 if (range0_sizek > state->range_sizek) {
362
363 /* One hole in middle or at the end: */
364 hole_sizek = range0_sizek - state->range_sizek - second_sizek;
365
366 /* Hole size should be less than half of range0 size: */
367 if (hole_sizek >= (range0_sizek >> 1) &&
368 range0_sizek >= chunk_sizek) {
369 range0_sizek -= chunk_sizek;
370 second_sizek = 0;
371 hole_sizek = 0;
372
373 goto second_try;
374 }
375 }
376
377 if (range0_sizek) {
378 Dprintk("range0: %016lx - %016lx\n",
379 range0_basek<<10,
380 (range0_basek + range0_sizek)<<10);
381 state->reg = range_to_mtrr(state->reg, range0_basek,
382 range0_sizek, MTRR_TYPE_WRBACK);
383 }
384
385 if (range0_sizek < state->range_sizek) {
386 /* Need to handle left over range: */
387 range_sizek = state->range_sizek - range0_sizek;
388
389 Dprintk("range: %016lx - %016lx\n",
390 range_basek<<10,
391 (range_basek + range_sizek)<<10);
392
393 state->reg = range_to_mtrr(state->reg, range_basek,
394 range_sizek, MTRR_TYPE_WRBACK);
395 }
396
397 if (hole_sizek) {
398 hole_basek = range_basek - hole_sizek - second_sizek;
399 Dprintk("hole: %016lx - %016lx\n",
400 hole_basek<<10,
401 (hole_basek + hole_sizek)<<10);
402 state->reg = range_to_mtrr(state->reg, hole_basek,
403 hole_sizek, MTRR_TYPE_UNCACHABLE);
404 }
405
406 return second_sizek;
407 }
408
409 static void __init
410 set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn,
411 unsigned long size_pfn)
412 {
413 unsigned long basek, sizek;
414 unsigned long second_sizek = 0;
415
416 if (state->reg >= num_var_ranges)
417 return;
418
419 basek = base_pfn << (PAGE_SHIFT - 10);
420 sizek = size_pfn << (PAGE_SHIFT - 10);
421
422 /* See if I can merge with the last range: */
423 if ((basek <= 1024) ||
424 (state->range_startk + state->range_sizek == basek)) {
425 unsigned long endk = basek + sizek;
426 state->range_sizek = endk - state->range_startk;
427 return;
428 }
429 /* Write the range mtrrs: */
430 if (state->range_sizek != 0)
431 second_sizek = range_to_mtrr_with_hole(state, basek, sizek);
432
433 /* Allocate an msr: */
434 state->range_startk = basek + second_sizek;
435 state->range_sizek = sizek - second_sizek;
436 }
437
438 /* Mininum size of mtrr block that can take hole: */
439 static u64 mtrr_chunk_size __initdata = (256ULL<<20);
440
441 static int __init parse_mtrr_chunk_size_opt(char *p)
442 {
443 if (!p)
444 return -EINVAL;
445 mtrr_chunk_size = memparse(p, &p);
446 return 0;
447 }
448 early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);
449
450 /* Granularity of mtrr of block: */
451 static u64 mtrr_gran_size __initdata;
452
453 static int __init parse_mtrr_gran_size_opt(char *p)
454 {
455 if (!p)
456 return -EINVAL;
457 mtrr_gran_size = memparse(p, &p);
458 return 0;
459 }
460 early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);
461
462 static unsigned long nr_mtrr_spare_reg __initdata =
463 CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
464
465 static int __init parse_mtrr_spare_reg(char *arg)
466 {
467 if (arg)
468 nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
469 return 0;
470 }
471 early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
472
473 static int __init
474 x86_setup_var_mtrrs(struct range *range, int nr_range,
475 u64 chunk_size, u64 gran_size)
476 {
477 struct var_mtrr_state var_state;
478 int num_reg;
479 int i;
480
481 var_state.range_startk = 0;
482 var_state.range_sizek = 0;
483 var_state.reg = 0;
484 var_state.chunk_sizek = chunk_size >> 10;
485 var_state.gran_sizek = gran_size >> 10;
486
487 memset(range_state, 0, sizeof(range_state));
488
489 /* Write the range: */
490 for (i = 0; i < nr_range; i++) {
491 set_var_mtrr_range(&var_state, range[i].start,
492 range[i].end - range[i].start);
493 }
494
495 /* Write the last range: */
496 if (var_state.range_sizek != 0)
497 range_to_mtrr_with_hole(&var_state, 0, 0);
498
499 num_reg = var_state.reg;
500 /* Clear out the extra MTRR's: */
501 while (var_state.reg < num_var_ranges) {
502 save_var_mtrr(var_state.reg, 0, 0, 0);
503 var_state.reg++;
504 }
505
506 return num_reg;
507 }
508
509 struct mtrr_cleanup_result {
510 unsigned long gran_sizek;
511 unsigned long chunk_sizek;
512 unsigned long lose_cover_sizek;
513 unsigned int num_reg;
514 int bad;
515 };
516
517 /*
518 * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G
519 * chunk size: gran_size, ..., 2G
520 * so we need (1+16)*8
521 */
522 #define NUM_RESULT 136
523 #define PSHIFT (PAGE_SHIFT - 10)
524
525 static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
526 static unsigned long __initdata min_loss_pfn[RANGE_NUM];
527
528 static void __init print_out_mtrr_range_state(void)
529 {
530 char start_factor = 'K', size_factor = 'K';
531 unsigned long start_base, size_base;
532 mtrr_type type;
533 int i;
534
535 for (i = 0; i < num_var_ranges; i++) {
536
537 size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10);
538 if (!size_base)
539 continue;
540
541 size_base = to_size_factor(size_base, &size_factor),
542 start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10);
543 start_base = to_size_factor(start_base, &start_factor),
544 type = range_state[i].type;
545
546 printk(KERN_DEBUG "reg %d, base: %ld%cB, range: %ld%cB, type %s\n",
547 i, start_base, start_factor,
548 size_base, size_factor,
549 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
550 ((type == MTRR_TYPE_WRPROT) ? "WP" :
551 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other"))
552 );
553 }
554 }
555
556 static int __init mtrr_need_cleanup(void)
557 {
558 int i;
559 mtrr_type type;
560 unsigned long size;
561 /* Extra one for all 0: */
562 int num[MTRR_NUM_TYPES + 1];
563
564 /* Check entries number: */
565 memset(num, 0, sizeof(num));
566 for (i = 0; i < num_var_ranges; i++) {
567 type = range_state[i].type;
568 size = range_state[i].size_pfn;
569 if (type >= MTRR_NUM_TYPES)
570 continue;
571 if (!size)
572 type = MTRR_NUM_TYPES;
573 num[type]++;
574 }
575
576 /* Check if we got UC entries: */
577 if (!num[MTRR_TYPE_UNCACHABLE])
578 return 0;
579
580 /* Check if we only had WB and UC */
581 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
582 num_var_ranges - num[MTRR_NUM_TYPES])
583 return 0;
584
585 return 1;
586 }
587
588 static unsigned long __initdata range_sums;
589
590 static void __init
591 mtrr_calc_range_state(u64 chunk_size, u64 gran_size,
592 unsigned long x_remove_base,
593 unsigned long x_remove_size, int i)
594 {
595 static struct range range_new[RANGE_NUM];
596 unsigned long range_sums_new;
597 static int nr_range_new;
598 int num_reg;
599
600 /* Convert ranges to var ranges state: */
601 num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
602
603 /* We got new setting in range_state, check it: */
604 memset(range_new, 0, sizeof(range_new));
605 nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
606 x_remove_base, x_remove_size);
607 range_sums_new = sum_ranges(range_new, nr_range_new);
608
609 result[i].chunk_sizek = chunk_size >> 10;
610 result[i].gran_sizek = gran_size >> 10;
611 result[i].num_reg = num_reg;
612
613 if (range_sums < range_sums_new) {
614 result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT;
615 result[i].bad = 1;
616 } else {
617 result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT;
618 }
619
620 /* Double check it: */
621 if (!result[i].bad && !result[i].lose_cover_sizek) {
622 if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range)))
623 result[i].bad = 1;
624 }
625
626 if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg]))
627 min_loss_pfn[num_reg] = range_sums - range_sums_new;
628 }
629
630 static void __init mtrr_print_out_one_result(int i)
631 {
632 unsigned long gran_base, chunk_base, lose_base;
633 char gran_factor, chunk_factor, lose_factor;
634
635 gran_base = to_size_factor(result[i].gran_sizek, &gran_factor);
636 chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor);
637 lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor);
638
639 pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t",
640 result[i].bad ? "*BAD*" : " ",
641 gran_base, gran_factor, chunk_base, chunk_factor);
642 pr_cont("num_reg: %d \tlose cover RAM: %s%ld%c\n",
643 result[i].num_reg, result[i].bad ? "-" : "",
644 lose_base, lose_factor);
645 }
646
647 static int __init mtrr_search_optimal_index(void)
648 {
649 int num_reg_good;
650 int index_good;
651 int i;
652
653 if (nr_mtrr_spare_reg >= num_var_ranges)
654 nr_mtrr_spare_reg = num_var_ranges - 1;
655
656 num_reg_good = -1;
657 for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) {
658 if (!min_loss_pfn[i])
659 num_reg_good = i;
660 }
661
662 index_good = -1;
663 if (num_reg_good != -1) {
664 for (i = 0; i < NUM_RESULT; i++) {
665 if (!result[i].bad &&
666 result[i].num_reg == num_reg_good &&
667 !result[i].lose_cover_sizek) {
668 index_good = i;
669 break;
670 }
671 }
672 }
673
674 return index_good;
675 }
676
677 int __init mtrr_cleanup(unsigned address_bits)
678 {
679 unsigned long x_remove_base, x_remove_size;
680 unsigned long base, size, def, dummy;
681 u64 chunk_size, gran_size;
682 mtrr_type type;
683 int index_good;
684 int i;
685
686 if (!is_cpu(INTEL) || enable_mtrr_cleanup < 1)
687 return 0;
688
689 rdmsr(MSR_MTRRdefType, def, dummy);
690 def &= 0xff;
691 if (def != MTRR_TYPE_UNCACHABLE)
692 return 0;
693
694 /* Get it and store it aside: */
695 memset(range_state, 0, sizeof(range_state));
696 for (i = 0; i < num_var_ranges; i++) {
697 mtrr_if->get(i, &base, &size, &type);
698 range_state[i].base_pfn = base;
699 range_state[i].size_pfn = size;
700 range_state[i].type = type;
701 }
702
703 /* Check if we need handle it and can handle it: */
704 if (!mtrr_need_cleanup())
705 return 0;
706
707 /* Print original var MTRRs at first, for debugging: */
708 printk(KERN_DEBUG "original variable MTRRs\n");
709 print_out_mtrr_range_state();
710
711 memset(range, 0, sizeof(range));
712 x_remove_size = 0;
713 x_remove_base = 1 << (32 - PAGE_SHIFT);
714 if (mtrr_tom2)
715 x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base;
716
717 nr_range = x86_get_mtrr_mem_range(range, 0, x_remove_base, x_remove_size);
718 /*
719 * [0, 1M) should always be covered by var mtrr with WB
720 * and fixed mtrrs should take effect before var mtrr for it:
721 */
722 nr_range = add_range_with_merge(range, RANGE_NUM, nr_range, 0,
723 1ULL<<(20 - PAGE_SHIFT));
724 /* Sort the ranges: */
725 sort_range(range, nr_range);
726
727 range_sums = sum_ranges(range, nr_range);
728 printk(KERN_INFO "total RAM covered: %ldM\n",
729 range_sums >> (20 - PAGE_SHIFT));
730
731 if (mtrr_chunk_size && mtrr_gran_size) {
732 i = 0;
733 mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size,
734 x_remove_base, x_remove_size, i);
735
736 mtrr_print_out_one_result(i);
737
738 if (!result[i].bad) {
739 set_var_mtrr_all(address_bits);
740 printk(KERN_DEBUG "New variable MTRRs\n");
741 print_out_mtrr_range_state();
742 return 1;
743 }
744 printk(KERN_INFO "invalid mtrr_gran_size or mtrr_chunk_size, "
745 "will find optimal one\n");
746 }
747
748 i = 0;
749 memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
750 memset(result, 0, sizeof(result));
751 for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) {
752
753 for (chunk_size = gran_size; chunk_size < (1ULL<<32);
754 chunk_size <<= 1) {
755
756 if (i >= NUM_RESULT)
757 continue;
758
759 mtrr_calc_range_state(chunk_size, gran_size,
760 x_remove_base, x_remove_size, i);
761 if (debug_print) {
762 mtrr_print_out_one_result(i);
763 printk(KERN_INFO "\n");
764 }
765
766 i++;
767 }
768 }
769
770 /* Try to find the optimal index: */
771 index_good = mtrr_search_optimal_index();
772
773 if (index_good != -1) {
774 printk(KERN_INFO "Found optimal setting for mtrr clean up\n");
775 i = index_good;
776 mtrr_print_out_one_result(i);
777
778 /* Convert ranges to var ranges state: */
779 chunk_size = result[i].chunk_sizek;
780 chunk_size <<= 10;
781 gran_size = result[i].gran_sizek;
782 gran_size <<= 10;
783 x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
784 set_var_mtrr_all(address_bits);
785 printk(KERN_DEBUG "New variable MTRRs\n");
786 print_out_mtrr_range_state();
787 return 1;
788 } else {
789 /* print out all */
790 for (i = 0; i < NUM_RESULT; i++)
791 mtrr_print_out_one_result(i);
792 }
793
794 printk(KERN_INFO "mtrr_cleanup: can not find optimal value\n");
795 printk(KERN_INFO "please specify mtrr_gran_size/mtrr_chunk_size\n");
796
797 return 0;
798 }
799 #else
800 int __init mtrr_cleanup(unsigned address_bits)
801 {
802 return 0;
803 }
804 #endif
805
806 static int disable_mtrr_trim;
807
808 static int __init disable_mtrr_trim_setup(char *str)
809 {
810 disable_mtrr_trim = 1;
811 return 0;
812 }
813 early_param("disable_mtrr_trim", disable_mtrr_trim_setup);
814
815 /*
816 * Newer AMD K8s and later CPUs have a special magic MSR way to force WB
817 * for memory >4GB. Check for that here.
818 * Note this won't check if the MTRRs < 4GB where the magic bit doesn't
819 * apply to are wrong, but so far we don't know of any such case in the wild.
820 */
821 #define Tom2Enabled (1U << 21)
822 #define Tom2ForceMemTypeWB (1U << 22)
823
824 int __init amd_special_default_mtrr(void)
825 {
826 u32 l, h;
827
828 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
829 return 0;
830 if (boot_cpu_data.x86 < 0xf)
831 return 0;
832 /* In case some hypervisor doesn't pass SYSCFG through: */
833 if (rdmsr_safe(MSR_K8_SYSCFG, &l, &h) < 0)
834 return 0;
835 /*
836 * Memory between 4GB and top of mem is forced WB by this magic bit.
837 * Reserved before K8RevF, but should be zero there.
838 */
839 if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) ==
840 (Tom2Enabled | Tom2ForceMemTypeWB))
841 return 1;
842 return 0;
843 }
844
845 static u64 __init
846 real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
847 {
848 u64 trim_start, trim_size;
849
850 trim_start = start_pfn;
851 trim_start <<= PAGE_SHIFT;
852
853 trim_size = limit_pfn;
854 trim_size <<= PAGE_SHIFT;
855 trim_size -= trim_start;
856
857 return e820_update_range(trim_start, trim_size, E820_RAM, E820_RESERVED);
858 }
859
860 /**
861 * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs
862 * @end_pfn: ending page frame number
863 *
864 * Some buggy BIOSes don't setup the MTRRs properly for systems with certain
865 * memory configurations. This routine checks that the highest MTRR matches
866 * the end of memory, to make sure the MTRRs having a write back type cover
867 * all of the memory the kernel is intending to use. If not, it'll trim any
868 * memory off the end by adjusting end_pfn, removing it from the kernel's
869 * allocation pools, warning the user with an obnoxious message.
870 */
871 int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
872 {
873 unsigned long i, base, size, highest_pfn = 0, def, dummy;
874 mtrr_type type;
875 u64 total_trim_size;
876 /* extra one for all 0 */
877 int num[MTRR_NUM_TYPES + 1];
878
879 /*
880 * Make sure we only trim uncachable memory on machines that
881 * support the Intel MTRR architecture:
882 */
883 if (!is_cpu(INTEL) || disable_mtrr_trim)
884 return 0;
885
886 rdmsr(MSR_MTRRdefType, def, dummy);
887 def &= 0xff;
888 if (def != MTRR_TYPE_UNCACHABLE)
889 return 0;
890
891 /* Get it and store it aside: */
892 memset(range_state, 0, sizeof(range_state));
893 for (i = 0; i < num_var_ranges; i++) {
894 mtrr_if->get(i, &base, &size, &type);
895 range_state[i].base_pfn = base;
896 range_state[i].size_pfn = size;
897 range_state[i].type = type;
898 }
899
900 /* Find highest cached pfn: */
901 for (i = 0; i < num_var_ranges; i++) {
902 type = range_state[i].type;
903 if (type != MTRR_TYPE_WRBACK)
904 continue;
905 base = range_state[i].base_pfn;
906 size = range_state[i].size_pfn;
907 if (highest_pfn < base + size)
908 highest_pfn = base + size;
909 }
910
911 /* kvm/qemu doesn't have mtrr set right, don't trim them all: */
912 if (!highest_pfn) {
913 printk(KERN_INFO "CPU MTRRs all blank - virtualized system.\n");
914 return 0;
915 }
916
917 /* Check entries number: */
918 memset(num, 0, sizeof(num));
919 for (i = 0; i < num_var_ranges; i++) {
920 type = range_state[i].type;
921 if (type >= MTRR_NUM_TYPES)
922 continue;
923 size = range_state[i].size_pfn;
924 if (!size)
925 type = MTRR_NUM_TYPES;
926 num[type]++;
927 }
928
929 /* No entry for WB? */
930 if (!num[MTRR_TYPE_WRBACK])
931 return 0;
932
933 /* Check if we only had WB and UC: */
934 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
935 num_var_ranges - num[MTRR_NUM_TYPES])
936 return 0;
937
938 memset(range, 0, sizeof(range));
939 nr_range = 0;
940 if (mtrr_tom2) {
941 range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT));
942 range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT;
943 if (highest_pfn < range[nr_range].end)
944 highest_pfn = range[nr_range].end;
945 nr_range++;
946 }
947 nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);
948
949 /* Check the head: */
950 total_trim_size = 0;
951 if (range[0].start)
952 total_trim_size += real_trim_memory(0, range[0].start);
953
954 /* Check the holes: */
955 for (i = 0; i < nr_range - 1; i++) {
956 if (range[i].end < range[i+1].start)
957 total_trim_size += real_trim_memory(range[i].end,
958 range[i+1].start);
959 }
960
961 /* Check the top: */
962 i = nr_range - 1;
963 if (range[i].end < end_pfn)
964 total_trim_size += real_trim_memory(range[i].end,
965 end_pfn);
966
967 if (total_trim_size) {
968 pr_warning("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n", total_trim_size >> 20);
969
970 if (!changed_by_mtrr_cleanup)
971 WARN_ON(1);
972
973 pr_info("update e820 for mtrr\n");
974 update_e820();
975
976 return 1;
977 }
978
979 return 0;
980 }
CRIS linux kernel tree