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ACPI / util: cast data to u64 before shifting to fix sign extension
[deliverable/linux.git] / arch / x86 / kernel / cpu / mtrr / cleanup.c
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 & MTRR_STATE_MTRR_ENABLED) &&
102 (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) {
103 /* Var MTRR contains UC entry below 1M? Skip it: */
104 printk(BIOS_BUG_MSG, i);
105 if (base + size <= (1<<(20-PAGE_SHIFT)))
106 continue;
107 size -= (1<<(20-PAGE_SHIFT)) - base;
108 base = 1<<(20-PAGE_SHIFT);
109 }
110 subtract_range(range, RANGE_NUM, base, base + size);
111 }
112 if (extra_remove_size)
113 subtract_range(range, RANGE_NUM, extra_remove_base,
114 extra_remove_base + extra_remove_size);
115
116 if (debug_print) {
117 printk(KERN_DEBUG "After UC checking\n");
118 for (i = 0; i < RANGE_NUM; i++) {
119 if (!range[i].end)
120 continue;
121 printk(KERN_DEBUG "MTRR MAP PFN: %016llx - %016llx\n",
122 range[i].start, range[i].end);
123 }
124 }
125
126 /* sort the ranges */
127 nr_range = clean_sort_range(range, RANGE_NUM);
128 if (debug_print) {
129 printk(KERN_DEBUG "After sorting\n");
130 for (i = 0; i < nr_range; i++)
131 printk(KERN_DEBUG "MTRR MAP PFN: %016llx - %016llx\n",
132 range[i].start, range[i].end);
133 }
134
135 return nr_range;
136 }
137
138 #ifdef CONFIG_MTRR_SANITIZER
139
140 static unsigned long __init sum_ranges(struct range *range, int nr_range)
141 {
142 unsigned long sum = 0;
143 int i;
144
145 for (i = 0; i < nr_range; i++)
146 sum += range[i].end - range[i].start;
147
148 return sum;
149 }
150
151 static int enable_mtrr_cleanup __initdata =
152 CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
153
154 static int __init disable_mtrr_cleanup_setup(char *str)
155 {
156 enable_mtrr_cleanup = 0;
157 return 0;
158 }
159 early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
160
161 static int __init enable_mtrr_cleanup_setup(char *str)
162 {
163 enable_mtrr_cleanup = 1;
164 return 0;
165 }
166 early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup);
167
168 static int __init mtrr_cleanup_debug_setup(char *str)
169 {
170 debug_print = 1;
171 return 0;
172 }
173 early_param("mtrr_cleanup_debug", mtrr_cleanup_debug_setup);
174
175 static void __init
176 set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
177 unsigned char type, unsigned int address_bits)
178 {
179 u32 base_lo, base_hi, mask_lo, mask_hi;
180 u64 base, mask;
181
182 if (!sizek) {
183 fill_mtrr_var_range(reg, 0, 0, 0, 0);
184 return;
185 }
186
187 mask = (1ULL << address_bits) - 1;
188 mask &= ~((((u64)sizek) << 10) - 1);
189
190 base = ((u64)basek) << 10;
191
192 base |= type;
193 mask |= 0x800;
194
195 base_lo = base & ((1ULL<<32) - 1);
196 base_hi = base >> 32;
197
198 mask_lo = mask & ((1ULL<<32) - 1);
199 mask_hi = mask >> 32;
200
201 fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
202 }
203
204 static void __init
205 save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
206 unsigned char type)
207 {
208 range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
209 range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
210 range_state[reg].type = type;
211 }
212
213 static void __init set_var_mtrr_all(unsigned int address_bits)
214 {
215 unsigned long basek, sizek;
216 unsigned char type;
217 unsigned int reg;
218
219 for (reg = 0; reg < num_var_ranges; reg++) {
220 basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
221 sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
222 type = range_state[reg].type;
223
224 set_var_mtrr(reg, basek, sizek, type, address_bits);
225 }
226 }
227
228 static unsigned long to_size_factor(unsigned long sizek, char *factorp)
229 {
230 unsigned long base = sizek;
231 char factor;
232
233 if (base & ((1<<10) - 1)) {
234 /* Not MB-aligned: */
235 factor = 'K';
236 } else if (base & ((1<<20) - 1)) {
237 factor = 'M';
238 base >>= 10;
239 } else {
240 factor = 'G';
241 base >>= 20;
242 }
243
244 *factorp = factor;
245
246 return base;
247 }
248
249 static unsigned int __init
250 range_to_mtrr(unsigned int reg, unsigned long range_startk,
251 unsigned long range_sizek, unsigned char type)
252 {
253 if (!range_sizek || (reg >= num_var_ranges))
254 return reg;
255
256 while (range_sizek) {
257 unsigned long max_align, align;
258 unsigned long sizek;
259
260 /* Compute the maximum size with which we can make a range: */
261 if (range_startk)
262 max_align = __ffs(range_startk);
263 else
264 max_align = BITS_PER_LONG - 1;
265
266 align = __fls(range_sizek);
267 if (align > max_align)
268 align = max_align;
269
270 sizek = 1UL << align;
271 if (debug_print) {
272 char start_factor = 'K', size_factor = 'K';
273 unsigned long start_base, size_base;
274
275 start_base = to_size_factor(range_startk, &start_factor);
276 size_base = to_size_factor(sizek, &size_factor);
277
278 Dprintk("Setting variable MTRR %d, "
279 "base: %ld%cB, range: %ld%cB, type %s\n",
280 reg, start_base, start_factor,
281 size_base, size_factor,
282 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
283 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")
284 );
285 }
286 save_var_mtrr(reg++, range_startk, sizek, type);
287 range_startk += sizek;
288 range_sizek -= sizek;
289 if (reg >= num_var_ranges)
290 break;
291 }
292 return reg;
293 }
294
295 static unsigned __init
296 range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
297 unsigned long sizek)
298 {
299 unsigned long hole_basek, hole_sizek;
300 unsigned long second_basek, second_sizek;
301 unsigned long range0_basek, range0_sizek;
302 unsigned long range_basek, range_sizek;
303 unsigned long chunk_sizek;
304 unsigned long gran_sizek;
305
306 hole_basek = 0;
307 hole_sizek = 0;
308 second_basek = 0;
309 second_sizek = 0;
310 chunk_sizek = state->chunk_sizek;
311 gran_sizek = state->gran_sizek;
312
313 /* Align with gran size, prevent small block used up MTRRs: */
314 range_basek = ALIGN(state->range_startk, gran_sizek);
315 if ((range_basek > basek) && basek)
316 return second_sizek;
317
318 state->range_sizek -= (range_basek - state->range_startk);
319 range_sizek = ALIGN(state->range_sizek, gran_sizek);
320
321 while (range_sizek > state->range_sizek) {
322 range_sizek -= gran_sizek;
323 if (!range_sizek)
324 return 0;
325 }
326 state->range_sizek = range_sizek;
327
328 /* Try to append some small hole: */
329 range0_basek = state->range_startk;
330 range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
331
332 /* No increase: */
333 if (range0_sizek == state->range_sizek) {
334 Dprintk("rangeX: %016lx - %016lx\n",
335 range0_basek<<10,
336 (range0_basek + state->range_sizek)<<10);
337 state->reg = range_to_mtrr(state->reg, range0_basek,
338 state->range_sizek, MTRR_TYPE_WRBACK);
339 return 0;
340 }
341
342 /* Only cut back when it is not the last: */
343 if (sizek) {
344 while (range0_basek + range0_sizek > (basek + sizek)) {
345 if (range0_sizek >= chunk_sizek)
346 range0_sizek -= chunk_sizek;
347 else
348 range0_sizek = 0;
349
350 if (!range0_sizek)
351 break;
352 }
353 }
354
355 second_try:
356 range_basek = range0_basek + range0_sizek;
357
358 /* One hole in the middle: */
359 if (range_basek > basek && range_basek <= (basek + sizek))
360 second_sizek = range_basek - basek;
361
362 if (range0_sizek > state->range_sizek) {
363
364 /* One hole in middle or at the end: */
365 hole_sizek = range0_sizek - state->range_sizek - second_sizek;
366
367 /* Hole size should be less than half of range0 size: */
368 if (hole_sizek >= (range0_sizek >> 1) &&
369 range0_sizek >= chunk_sizek) {
370 range0_sizek -= chunk_sizek;
371 second_sizek = 0;
372 hole_sizek = 0;
373
374 goto second_try;
375 }
376 }
377
378 if (range0_sizek) {
379 Dprintk("range0: %016lx - %016lx\n",
380 range0_basek<<10,
381 (range0_basek + range0_sizek)<<10);
382 state->reg = range_to_mtrr(state->reg, range0_basek,
383 range0_sizek, MTRR_TYPE_WRBACK);
384 }
385
386 if (range0_sizek < state->range_sizek) {
387 /* Need to handle left over range: */
388 range_sizek = state->range_sizek - range0_sizek;
389
390 Dprintk("range: %016lx - %016lx\n",
391 range_basek<<10,
392 (range_basek + range_sizek)<<10);
393
394 state->reg = range_to_mtrr(state->reg, range_basek,
395 range_sizek, MTRR_TYPE_WRBACK);
396 }
397
398 if (hole_sizek) {
399 hole_basek = range_basek - hole_sizek - second_sizek;
400 Dprintk("hole: %016lx - %016lx\n",
401 hole_basek<<10,
402 (hole_basek + hole_sizek)<<10);
403 state->reg = range_to_mtrr(state->reg, hole_basek,
404 hole_sizek, MTRR_TYPE_UNCACHABLE);
405 }
406
407 return second_sizek;
408 }
409
410 static void __init
411 set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn,
412 unsigned long size_pfn)
413 {
414 unsigned long basek, sizek;
415 unsigned long second_sizek = 0;
416
417 if (state->reg >= num_var_ranges)
418 return;
419
420 basek = base_pfn << (PAGE_SHIFT - 10);
421 sizek = size_pfn << (PAGE_SHIFT - 10);
422
423 /* See if I can merge with the last range: */
424 if ((basek <= 1024) ||
425 (state->range_startk + state->range_sizek == basek)) {
426 unsigned long endk = basek + sizek;
427 state->range_sizek = endk - state->range_startk;
428 return;
429 }
430 /* Write the range mtrrs: */
431 if (state->range_sizek != 0)
432 second_sizek = range_to_mtrr_with_hole(state, basek, sizek);
433
434 /* Allocate an msr: */
435 state->range_startk = basek + second_sizek;
436 state->range_sizek = sizek - second_sizek;
437 }
438
439 /* Mininum size of mtrr block that can take hole: */
440 static u64 mtrr_chunk_size __initdata = (256ULL<<20);
441
442 static int __init parse_mtrr_chunk_size_opt(char *p)
443 {
444 if (!p)
445 return -EINVAL;
446 mtrr_chunk_size = memparse(p, &p);
447 return 0;
448 }
449 early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);
450
451 /* Granularity of mtrr of block: */
452 static u64 mtrr_gran_size __initdata;
453
454 static int __init parse_mtrr_gran_size_opt(char *p)
455 {
456 if (!p)
457 return -EINVAL;
458 mtrr_gran_size = memparse(p, &p);
459 return 0;
460 }
461 early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);
462
463 static unsigned long nr_mtrr_spare_reg __initdata =
464 CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
465
466 static int __init parse_mtrr_spare_reg(char *arg)
467 {
468 if (arg)
469 nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
470 return 0;
471 }
472 early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
473
474 static int __init
475 x86_setup_var_mtrrs(struct range *range, int nr_range,
476 u64 chunk_size, u64 gran_size)
477 {
478 struct var_mtrr_state var_state;
479 int num_reg;
480 int i;
481
482 var_state.range_startk = 0;
483 var_state.range_sizek = 0;
484 var_state.reg = 0;
485 var_state.chunk_sizek = chunk_size >> 10;
486 var_state.gran_sizek = gran_size >> 10;
487
488 memset(range_state, 0, sizeof(range_state));
489
490 /* Write the range: */
491 for (i = 0; i < nr_range; i++) {
492 set_var_mtrr_range(&var_state, range[i].start,
493 range[i].end - range[i].start);
494 }
495
496 /* Write the last range: */
497 if (var_state.range_sizek != 0)
498 range_to_mtrr_with_hole(&var_state, 0, 0);
499
500 num_reg = var_state.reg;
501 /* Clear out the extra MTRR's: */
502 while (var_state.reg < num_var_ranges) {
503 save_var_mtrr(var_state.reg, 0, 0, 0);
504 var_state.reg++;
505 }
506
507 return num_reg;
508 }
509
510 struct mtrr_cleanup_result {
511 unsigned long gran_sizek;
512 unsigned long chunk_sizek;
513 unsigned long lose_cover_sizek;
514 unsigned int num_reg;
515 int bad;
516 };
517
518 /*
519 * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G
520 * chunk size: gran_size, ..., 2G
521 * so we need (1+16)*8
522 */
523 #define NUM_RESULT 136
524 #define PSHIFT (PAGE_SHIFT - 10)
525
526 static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
527 static unsigned long __initdata min_loss_pfn[RANGE_NUM];
528
529 static void __init print_out_mtrr_range_state(void)
530 {
531 char start_factor = 'K', size_factor = 'K';
532 unsigned long start_base, size_base;
533 mtrr_type type;
534 int i;
535
536 for (i = 0; i < num_var_ranges; i++) {
537
538 size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10);
539 if (!size_base)
540 continue;
541
542 size_base = to_size_factor(size_base, &size_factor),
543 start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10);
544 start_base = to_size_factor(start_base, &start_factor),
545 type = range_state[i].type;
546
547 printk(KERN_DEBUG "reg %d, base: %ld%cB, range: %ld%cB, type %s\n",
548 i, start_base, start_factor,
549 size_base, size_factor,
550 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
551 ((type == MTRR_TYPE_WRPROT) ? "WP" :
552 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other"))
553 );
554 }
555 }
556
557 static int __init mtrr_need_cleanup(void)
558 {
559 int i;
560 mtrr_type type;
561 unsigned long size;
562 /* Extra one for all 0: */
563 int num[MTRR_NUM_TYPES + 1];
564
565 /* Check entries number: */
566 memset(num, 0, sizeof(num));
567 for (i = 0; i < num_var_ranges; i++) {
568 type = range_state[i].type;
569 size = range_state[i].size_pfn;
570 if (type >= MTRR_NUM_TYPES)
571 continue;
572 if (!size)
573 type = MTRR_NUM_TYPES;
574 num[type]++;
575 }
576
577 /* Check if we got UC entries: */
578 if (!num[MTRR_TYPE_UNCACHABLE])
579 return 0;
580
581 /* Check if we only had WB and UC */
582 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
583 num_var_ranges - num[MTRR_NUM_TYPES])
584 return 0;
585
586 return 1;
587 }
588
589 static unsigned long __initdata range_sums;
590
591 static void __init
592 mtrr_calc_range_state(u64 chunk_size, u64 gran_size,
593 unsigned long x_remove_base,
594 unsigned long x_remove_size, int i)
595 {
596 /*
597 * range_new should really be an automatic variable, but
598 * putting 4096 bytes on the stack is frowned upon, to put it
599 * mildly. It is safe to make it a static __initdata variable,
600 * since mtrr_calc_range_state is only called during init and
601 * there's no way it will call itself recursively.
602 */
603 static struct range range_new[RANGE_NUM] __initdata;
604 unsigned long range_sums_new;
605 int nr_range_new;
606 int num_reg;
607
608 /* Convert ranges to var ranges state: */
609 num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
610
611 /* We got new setting in range_state, check it: */
612 memset(range_new, 0, sizeof(range_new));
613 nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
614 x_remove_base, x_remove_size);
615 range_sums_new = sum_ranges(range_new, nr_range_new);
616
617 result[i].chunk_sizek = chunk_size >> 10;
618 result[i].gran_sizek = gran_size >> 10;
619 result[i].num_reg = num_reg;
620
621 if (range_sums < range_sums_new) {
622 result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT;
623 result[i].bad = 1;
624 } else {
625 result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT;
626 }
627
628 /* Double check it: */
629 if (!result[i].bad && !result[i].lose_cover_sizek) {
630 if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range)))
631 result[i].bad = 1;
632 }
633
634 if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg]))
635 min_loss_pfn[num_reg] = range_sums - range_sums_new;
636 }
637
638 static void __init mtrr_print_out_one_result(int i)
639 {
640 unsigned long gran_base, chunk_base, lose_base;
641 char gran_factor, chunk_factor, lose_factor;
642
643 gran_base = to_size_factor(result[i].gran_sizek, &gran_factor);
644 chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor);
645 lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor);
646
647 pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t",
648 result[i].bad ? "*BAD*" : " ",
649 gran_base, gran_factor, chunk_base, chunk_factor);
650 pr_cont("num_reg: %d \tlose cover RAM: %s%ld%c\n",
651 result[i].num_reg, result[i].bad ? "-" : "",
652 lose_base, lose_factor);
653 }
654
655 static int __init mtrr_search_optimal_index(void)
656 {
657 int num_reg_good;
658 int index_good;
659 int i;
660
661 if (nr_mtrr_spare_reg >= num_var_ranges)
662 nr_mtrr_spare_reg = num_var_ranges - 1;
663
664 num_reg_good = -1;
665 for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) {
666 if (!min_loss_pfn[i])
667 num_reg_good = i;
668 }
669
670 index_good = -1;
671 if (num_reg_good != -1) {
672 for (i = 0; i < NUM_RESULT; i++) {
673 if (!result[i].bad &&
674 result[i].num_reg == num_reg_good &&
675 !result[i].lose_cover_sizek) {
676 index_good = i;
677 break;
678 }
679 }
680 }
681
682 return index_good;
683 }
684
685 int __init mtrr_cleanup(unsigned address_bits)
686 {
687 unsigned long x_remove_base, x_remove_size;
688 unsigned long base, size, def, dummy;
689 u64 chunk_size, gran_size;
690 mtrr_type type;
691 int index_good;
692 int i;
693
694 if (!is_cpu(INTEL) || enable_mtrr_cleanup < 1)
695 return 0;
696
697 rdmsr(MSR_MTRRdefType, def, dummy);
698 def &= 0xff;
699 if (def != MTRR_TYPE_UNCACHABLE)
700 return 0;
701
702 /* Get it and store it aside: */
703 memset(range_state, 0, sizeof(range_state));
704 for (i = 0; i < num_var_ranges; i++) {
705 mtrr_if->get(i, &base, &size, &type);
706 range_state[i].base_pfn = base;
707 range_state[i].size_pfn = size;
708 range_state[i].type = type;
709 }
710
711 /* Check if we need handle it and can handle it: */
712 if (!mtrr_need_cleanup())
713 return 0;
714
715 /* Print original var MTRRs at first, for debugging: */
716 printk(KERN_DEBUG "original variable MTRRs\n");
717 print_out_mtrr_range_state();
718
719 memset(range, 0, sizeof(range));
720 x_remove_size = 0;
721 x_remove_base = 1 << (32 - PAGE_SHIFT);
722 if (mtrr_tom2)
723 x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base;
724
725 /*
726 * [0, 1M) should always be covered by var mtrr with WB
727 * and fixed mtrrs should take effect before var mtrr for it:
728 */
729 nr_range = add_range_with_merge(range, RANGE_NUM, 0, 0,
730 1ULL<<(20 - PAGE_SHIFT));
731 /* add from var mtrr at last */
732 nr_range = x86_get_mtrr_mem_range(range, nr_range,
733 x_remove_base, x_remove_size);
734
735 range_sums = sum_ranges(range, nr_range);
736 printk(KERN_INFO "total RAM covered: %ldM\n",
737 range_sums >> (20 - PAGE_SHIFT));
738
739 if (mtrr_chunk_size && mtrr_gran_size) {
740 i = 0;
741 mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size,
742 x_remove_base, x_remove_size, i);
743
744 mtrr_print_out_one_result(i);
745
746 if (!result[i].bad) {
747 set_var_mtrr_all(address_bits);
748 printk(KERN_DEBUG "New variable MTRRs\n");
749 print_out_mtrr_range_state();
750 return 1;
751 }
752 printk(KERN_INFO "invalid mtrr_gran_size or mtrr_chunk_size, "
753 "will find optimal one\n");
754 }
755
756 i = 0;
757 memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
758 memset(result, 0, sizeof(result));
759 for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) {
760
761 for (chunk_size = gran_size; chunk_size < (1ULL<<32);
762 chunk_size <<= 1) {
763
764 if (i >= NUM_RESULT)
765 continue;
766
767 mtrr_calc_range_state(chunk_size, gran_size,
768 x_remove_base, x_remove_size, i);
769 if (debug_print) {
770 mtrr_print_out_one_result(i);
771 printk(KERN_INFO "\n");
772 }
773
774 i++;
775 }
776 }
777
778 /* Try to find the optimal index: */
779 index_good = mtrr_search_optimal_index();
780
781 if (index_good != -1) {
782 printk(KERN_INFO "Found optimal setting for mtrr clean up\n");
783 i = index_good;
784 mtrr_print_out_one_result(i);
785
786 /* Convert ranges to var ranges state: */
787 chunk_size = result[i].chunk_sizek;
788 chunk_size <<= 10;
789 gran_size = result[i].gran_sizek;
790 gran_size <<= 10;
791 x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
792 set_var_mtrr_all(address_bits);
793 printk(KERN_DEBUG "New variable MTRRs\n");
794 print_out_mtrr_range_state();
795 return 1;
796 } else {
797 /* print out all */
798 for (i = 0; i < NUM_RESULT; i++)
799 mtrr_print_out_one_result(i);
800 }
801
802 printk(KERN_INFO "mtrr_cleanup: can not find optimal value\n");
803 printk(KERN_INFO "please specify mtrr_gran_size/mtrr_chunk_size\n");
804
805 return 0;
806 }
807 #else
808 int __init mtrr_cleanup(unsigned address_bits)
809 {
810 return 0;
811 }
812 #endif
813
814 static int disable_mtrr_trim;
815
816 static int __init disable_mtrr_trim_setup(char *str)
817 {
818 disable_mtrr_trim = 1;
819 return 0;
820 }
821 early_param("disable_mtrr_trim", disable_mtrr_trim_setup);
822
823 /*
824 * Newer AMD K8s and later CPUs have a special magic MSR way to force WB
825 * for memory >4GB. Check for that here.
826 * Note this won't check if the MTRRs < 4GB where the magic bit doesn't
827 * apply to are wrong, but so far we don't know of any such case in the wild.
828 */
829 #define Tom2Enabled (1U << 21)
830 #define Tom2ForceMemTypeWB (1U << 22)
831
832 int __init amd_special_default_mtrr(void)
833 {
834 u32 l, h;
835
836 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
837 return 0;
838 if (boot_cpu_data.x86 < 0xf)
839 return 0;
840 /* In case some hypervisor doesn't pass SYSCFG through: */
841 if (rdmsr_safe(MSR_K8_SYSCFG, &l, &h) < 0)
842 return 0;
843 /*
844 * Memory between 4GB and top of mem is forced WB by this magic bit.
845 * Reserved before K8RevF, but should be zero there.
846 */
847 if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) ==
848 (Tom2Enabled | Tom2ForceMemTypeWB))
849 return 1;
850 return 0;
851 }
852
853 static u64 __init
854 real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
855 {
856 u64 trim_start, trim_size;
857
858 trim_start = start_pfn;
859 trim_start <<= PAGE_SHIFT;
860
861 trim_size = limit_pfn;
862 trim_size <<= PAGE_SHIFT;
863 trim_size -= trim_start;
864
865 return e820_update_range(trim_start, trim_size, E820_RAM, E820_RESERVED);
866 }
867
868 /**
869 * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs
870 * @end_pfn: ending page frame number
871 *
872 * Some buggy BIOSes don't setup the MTRRs properly for systems with certain
873 * memory configurations. This routine checks that the highest MTRR matches
874 * the end of memory, to make sure the MTRRs having a write back type cover
875 * all of the memory the kernel is intending to use. If not, it'll trim any
876 * memory off the end by adjusting end_pfn, removing it from the kernel's
877 * allocation pools, warning the user with an obnoxious message.
878 */
879 int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
880 {
881 unsigned long i, base, size, highest_pfn = 0, def, dummy;
882 mtrr_type type;
883 u64 total_trim_size;
884 /* extra one for all 0 */
885 int num[MTRR_NUM_TYPES + 1];
886
887 /*
888 * Make sure we only trim uncachable memory on machines that
889 * support the Intel MTRR architecture:
890 */
891 if (!is_cpu(INTEL) || disable_mtrr_trim)
892 return 0;
893
894 rdmsr(MSR_MTRRdefType, def, dummy);
895 def &= 0xff;
896 if (def != MTRR_TYPE_UNCACHABLE)
897 return 0;
898
899 /* Get it and store it aside: */
900 memset(range_state, 0, sizeof(range_state));
901 for (i = 0; i < num_var_ranges; i++) {
902 mtrr_if->get(i, &base, &size, &type);
903 range_state[i].base_pfn = base;
904 range_state[i].size_pfn = size;
905 range_state[i].type = type;
906 }
907
908 /* Find highest cached pfn: */
909 for (i = 0; i < num_var_ranges; i++) {
910 type = range_state[i].type;
911 if (type != MTRR_TYPE_WRBACK)
912 continue;
913 base = range_state[i].base_pfn;
914 size = range_state[i].size_pfn;
915 if (highest_pfn < base + size)
916 highest_pfn = base + size;
917 }
918
919 /* kvm/qemu doesn't have mtrr set right, don't trim them all: */
920 if (!highest_pfn) {
921 printk(KERN_INFO "CPU MTRRs all blank - virtualized system.\n");
922 return 0;
923 }
924
925 /* Check entries number: */
926 memset(num, 0, sizeof(num));
927 for (i = 0; i < num_var_ranges; i++) {
928 type = range_state[i].type;
929 if (type >= MTRR_NUM_TYPES)
930 continue;
931 size = range_state[i].size_pfn;
932 if (!size)
933 type = MTRR_NUM_TYPES;
934 num[type]++;
935 }
936
937 /* No entry for WB? */
938 if (!num[MTRR_TYPE_WRBACK])
939 return 0;
940
941 /* Check if we only had WB and UC: */
942 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
943 num_var_ranges - num[MTRR_NUM_TYPES])
944 return 0;
945
946 memset(range, 0, sizeof(range));
947 nr_range = 0;
948 if (mtrr_tom2) {
949 range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT));
950 range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT;
951 if (highest_pfn < range[nr_range].end)
952 highest_pfn = range[nr_range].end;
953 nr_range++;
954 }
955 nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);
956
957 /* Check the head: */
958 total_trim_size = 0;
959 if (range[0].start)
960 total_trim_size += real_trim_memory(0, range[0].start);
961
962 /* Check the holes: */
963 for (i = 0; i < nr_range - 1; i++) {
964 if (range[i].end < range[i+1].start)
965 total_trim_size += real_trim_memory(range[i].end,
966 range[i+1].start);
967 }
968
969 /* Check the top: */
970 i = nr_range - 1;
971 if (range[i].end < end_pfn)
972 total_trim_size += real_trim_memory(range[i].end,
973 end_pfn);
974
975 if (total_trim_size) {
976 pr_warning("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n", total_trim_size >> 20);
977
978 if (!changed_by_mtrr_cleanup)
979 WARN_ON(1);
980
981 pr_info("update e820 for mtrr\n");
982 update_e820();
983
984 return 1;
985 }
986
987 return 0;
988 }
Linux kernel - Deliverables
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