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drm/rockchip: vop2: Fix the windows switch between different layers
[drm/drm-misc.git] / arch / x86 / kernel / cpu / mtrr / cleanup.c
blob18cf79d6e2c5a9d02509eced1272c3fb0dea099b
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/init.h>
21 #include <linux/pci.h>
22 #include <linux/smp.h>
23 #include <linux/cpu.h>
24 #include <linux/mutex.h>
25 #include <linux/uaccess.h>
26 #include <linux/kvm_para.h>
27 #include <linux/range.h>
28
29 #include <asm/processor.h>
30 #include <asm/e820/api.h>
31 #include <asm/mtrr.h>
32 #include <asm/msr.h>
33
34 #include "mtrr.h"
35
36 struct var_mtrr_range_state {
37 unsigned long base_pfn;
38 unsigned long size_pfn;
39 mtrr_type type;
40 };
41
42 struct var_mtrr_state {
43 unsigned long range_startk;
44 unsigned long range_sizek;
45 unsigned long chunk_sizek;
46 unsigned long gran_sizek;
47 unsigned int reg;
48 };
49
50 /* Should be related to MTRR_VAR_RANGES nums */
51 #define RANGE_NUM 256
52
53 static struct range __initdata range[RANGE_NUM];
54 static int __initdata nr_range;
55
56 static struct var_mtrr_range_state __initdata range_state[RANGE_NUM];
57
58 #define BIOS_BUG_MSG \
59 "WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n"
60
61 static int __init
62 x86_get_mtrr_mem_range(struct range *range, int nr_range,
63 unsigned long extra_remove_base,
64 unsigned long extra_remove_size)
65 {
66 unsigned long base, size;
67 mtrr_type type;
68 int i;
69
70 for (i = 0; i < num_var_ranges; i++) {
71 type = range_state[i].type;
72 if (type != MTRR_TYPE_WRBACK)
73 continue;
74 base = range_state[i].base_pfn;
75 size = range_state[i].size_pfn;
76 nr_range = add_range_with_merge(range, RANGE_NUM, nr_range,
77 base, base + size);
78 }
79
80 Dprintk("After WB checking\n");
81 for (i = 0; i < nr_range; i++)
82 Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
83 range[i].start, range[i].end);
84
85 /* Take out UC ranges: */
86 for (i = 0; i < num_var_ranges; i++) {
87 type = range_state[i].type;
88 if (type != MTRR_TYPE_UNCACHABLE &&
89 type != MTRR_TYPE_WRPROT)
90 continue;
91 size = range_state[i].size_pfn;
92 if (!size)
93 continue;
94 base = range_state[i].base_pfn;
95 if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed &&
96 (mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
97 (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) {
98 /* Var MTRR contains UC entry below 1M? Skip it: */
99 pr_warn(BIOS_BUG_MSG, i);
100 if (base + size <= (1<<(20-PAGE_SHIFT)))
101 continue;
102 size -= (1<<(20-PAGE_SHIFT)) - base;
103 base = 1<<(20-PAGE_SHIFT);
104 }
105 subtract_range(range, RANGE_NUM, base, base + size);
106 }
107 if (extra_remove_size)
108 subtract_range(range, RANGE_NUM, extra_remove_base,
109 extra_remove_base + extra_remove_size);
110
111 Dprintk("After UC checking\n");
112 for (i = 0; i < RANGE_NUM; i++) {
113 if (!range[i].end)
114 continue;
115
116 Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
117 range[i].start, range[i].end);
118 }
119
120 /* sort the ranges */
121 nr_range = clean_sort_range(range, RANGE_NUM);
122
123 Dprintk("After sorting\n");
124 for (i = 0; i < nr_range; i++)
125 Dprintk("MTRR MAP PFN: %016llx - %016llx\n",
126 range[i].start, range[i].end);
127
128 return nr_range;
129 }
130
131 #ifdef CONFIG_MTRR_SANITIZER
132
133 static unsigned long __init sum_ranges(struct range *range, int nr_range)
134 {
135 unsigned long sum = 0;
136 int i;
137
138 for (i = 0; i < nr_range; i++)
139 sum += range[i].end - range[i].start;
140
141 return sum;
142 }
143
144 static int enable_mtrr_cleanup __initdata =
145 CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
146
147 static int __init disable_mtrr_cleanup_setup(char *str)
148 {
149 enable_mtrr_cleanup = 0;
150 return 0;
151 }
152 early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
153
154 static int __init enable_mtrr_cleanup_setup(char *str)
155 {
156 enable_mtrr_cleanup = 1;
157 return 0;
158 }
159 early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup);
160
161 static void __init
162 set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
163 unsigned char type)
164 {
165 u32 base_lo, base_hi, mask_lo, mask_hi;
166 u64 base, mask;
167
168 if (!sizek) {
169 fill_mtrr_var_range(reg, 0, 0, 0, 0);
170 return;
171 }
172
173 mask = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
174 mask &= ~((((u64)sizek) << 10) - 1);
175
176 base = ((u64)basek) << 10;
177
178 base |= type;
179 mask |= 0x800;
180
181 base_lo = base & ((1ULL<<32) - 1);
182 base_hi = base >> 32;
183
184 mask_lo = mask & ((1ULL<<32) - 1);
185 mask_hi = mask >> 32;
186
187 fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
188 }
189
190 static void __init
191 save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
192 unsigned char type)
193 {
194 range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
195 range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
196 range_state[reg].type = type;
197 }
198
199 static void __init set_var_mtrr_all(void)
200 {
201 unsigned long basek, sizek;
202 unsigned char type;
203 unsigned int reg;
204
205 for (reg = 0; reg < num_var_ranges; reg++) {
206 basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
207 sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
208 type = range_state[reg].type;
209
210 set_var_mtrr(reg, basek, sizek, type);
211 }
212 }
213
214 static unsigned long to_size_factor(unsigned long sizek, char *factorp)
215 {
216 unsigned long base = sizek;
217 char factor;
218
219 if (base & ((1<<10) - 1)) {
220 /* Not MB-aligned: */
221 factor = 'K';
222 } else if (base & ((1<<20) - 1)) {
223 factor = 'M';
224 base >>= 10;
225 } else {
226 factor = 'G';
227 base >>= 20;
228 }
229
230 *factorp = factor;
231
232 return base;
233 }
234
235 static unsigned int __init
236 range_to_mtrr(unsigned int reg, unsigned long range_startk,
237 unsigned long range_sizek, unsigned char type)
238 {
239 if (!range_sizek || (reg >= num_var_ranges))
240 return reg;
241
242 while (range_sizek) {
243 unsigned long max_align, align;
244 unsigned long sizek;
245
246 /* Compute the maximum size with which we can make a range: */
247 if (range_startk)
248 max_align = __ffs(range_startk);
249 else
250 max_align = BITS_PER_LONG - 1;
251
252 align = __fls(range_sizek);
253 if (align > max_align)
254 align = max_align;
255
256 sizek = 1UL << align;
257 if (mtrr_debug) {
258 char start_factor = 'K', size_factor = 'K';
259 unsigned long start_base, size_base;
260
261 start_base = to_size_factor(range_startk, &start_factor);
262 size_base = to_size_factor(sizek, &size_factor);
263
264 Dprintk("Setting variable MTRR %d, "
265 "base: %ld%cB, range: %ld%cB, type %s\n",
266 reg, start_base, start_factor,
267 size_base, size_factor,
268 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
269 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")
270 );
271 }
272 save_var_mtrr(reg++, range_startk, sizek, type);
273 range_startk += sizek;
274 range_sizek -= sizek;
275 if (reg >= num_var_ranges)
276 break;
277 }
278 return reg;
279 }
280
281 static unsigned __init
282 range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
283 unsigned long sizek)
284 {
285 unsigned long hole_basek, hole_sizek;
286 unsigned long second_sizek;
287 unsigned long range0_basek, range0_sizek;
288 unsigned long range_basek, range_sizek;
289 unsigned long chunk_sizek;
290 unsigned long gran_sizek;
291
292 hole_basek = 0;
293 hole_sizek = 0;
294 second_sizek = 0;
295 chunk_sizek = state->chunk_sizek;
296 gran_sizek = state->gran_sizek;
297
298 /* Align with gran size, prevent small block used up MTRRs: */
299 range_basek = ALIGN(state->range_startk, gran_sizek);
300 if ((range_basek > basek) && basek)
301 return second_sizek;
302
303 state->range_sizek -= (range_basek - state->range_startk);
304 range_sizek = ALIGN(state->range_sizek, gran_sizek);
305
306 while (range_sizek > state->range_sizek) {
307 range_sizek -= gran_sizek;
308 if (!range_sizek)
309 return 0;
310 }
311 state->range_sizek = range_sizek;
312
313 /* Try to append some small hole: */
314 range0_basek = state->range_startk;
315 range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
316
317 /* No increase: */
318 if (range0_sizek == state->range_sizek) {
319 Dprintk("rangeX: %016lx - %016lx\n",
320 range0_basek<<10,
321 (range0_basek + state->range_sizek)<<10);
322 state->reg = range_to_mtrr(state->reg, range0_basek,
323 state->range_sizek, MTRR_TYPE_WRBACK);
324 return 0;
325 }
326
327 /* Only cut back when it is not the last: */
328 if (sizek) {
329 while (range0_basek + range0_sizek > (basek + sizek)) {
330 if (range0_sizek >= chunk_sizek)
331 range0_sizek -= chunk_sizek;
332 else
333 range0_sizek = 0;
334
335 if (!range0_sizek)
336 break;
337 }
338 }
339
340 second_try:
341 range_basek = range0_basek + range0_sizek;
342
343 /* One hole in the middle: */
344 if (range_basek > basek && range_basek <= (basek + sizek))
345 second_sizek = range_basek - basek;
346
347 if (range0_sizek > state->range_sizek) {
348
349 /* One hole in middle or at the end: */
350 hole_sizek = range0_sizek - state->range_sizek - second_sizek;
351
352 /* Hole size should be less than half of range0 size: */
353 if (hole_sizek >= (range0_sizek >> 1) &&
354 range0_sizek >= chunk_sizek) {
355 range0_sizek -= chunk_sizek;
356 second_sizek = 0;
357 hole_sizek = 0;
358
359 goto second_try;
360 }
361 }
362
363 if (range0_sizek) {
364 Dprintk("range0: %016lx - %016lx\n",
365 range0_basek<<10,
366 (range0_basek + range0_sizek)<<10);
367 state->reg = range_to_mtrr(state->reg, range0_basek,
368 range0_sizek, MTRR_TYPE_WRBACK);
369 }
370
371 if (range0_sizek < state->range_sizek) {
372 /* Need to handle left over range: */
373 range_sizek = state->range_sizek - range0_sizek;
374
375 Dprintk("range: %016lx - %016lx\n",
376 range_basek<<10,
377 (range_basek + range_sizek)<<10);
378
379 state->reg = range_to_mtrr(state->reg, range_basek,
380 range_sizek, MTRR_TYPE_WRBACK);
381 }
382
383 if (hole_sizek) {
384 hole_basek = range_basek - hole_sizek - second_sizek;
385 Dprintk("hole: %016lx - %016lx\n",
386 hole_basek<<10,
387 (hole_basek + hole_sizek)<<10);
388 state->reg = range_to_mtrr(state->reg, hole_basek,
389 hole_sizek, MTRR_TYPE_UNCACHABLE);
390 }
391
392 return second_sizek;
393 }
394
395 static void __init
396 set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn,
397 unsigned long size_pfn)
398 {
399 unsigned long basek, sizek;
400 unsigned long second_sizek = 0;
401
402 if (state->reg >= num_var_ranges)
403 return;
404
405 basek = base_pfn << (PAGE_SHIFT - 10);
406 sizek = size_pfn << (PAGE_SHIFT - 10);
407
408 /* See if I can merge with the last range: */
409 if ((basek <= 1024) ||
410 (state->range_startk + state->range_sizek == basek)) {
411 unsigned long endk = basek + sizek;
412 state->range_sizek = endk - state->range_startk;
413 return;
414 }
415 /* Write the range mtrrs: */
416 if (state->range_sizek != 0)
417 second_sizek = range_to_mtrr_with_hole(state, basek, sizek);
418
419 /* Allocate an msr: */
420 state->range_startk = basek + second_sizek;
421 state->range_sizek = sizek - second_sizek;
422 }
423
424 /* Minimum size of mtrr block that can take hole: */
425 static u64 mtrr_chunk_size __initdata = (256ULL<<20);
426
427 static int __init parse_mtrr_chunk_size_opt(char *p)
428 {
429 if (!p)
430 return -EINVAL;
431 mtrr_chunk_size = memparse(p, &p);
432 return 0;
433 }
434 early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);
435
436 /* Granularity of mtrr of block: */
437 static u64 mtrr_gran_size __initdata;
438
439 static int __init parse_mtrr_gran_size_opt(char *p)
440 {
441 if (!p)
442 return -EINVAL;
443 mtrr_gran_size = memparse(p, &p);
444 return 0;
445 }
446 early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);
447
448 static unsigned long nr_mtrr_spare_reg __initdata =
449 CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
450
451 static int __init parse_mtrr_spare_reg(char *arg)
452 {
453 if (arg)
454 nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
455 return 0;
456 }
457 early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
458
459 static int __init
460 x86_setup_var_mtrrs(struct range *range, int nr_range,
461 u64 chunk_size, u64 gran_size)
462 {
463 struct var_mtrr_state var_state;
464 int num_reg;
465 int i;
466
467 var_state.range_startk = 0;
468 var_state.range_sizek = 0;
469 var_state.reg = 0;
470 var_state.chunk_sizek = chunk_size >> 10;
471 var_state.gran_sizek = gran_size >> 10;
472
473 memset(range_state, 0, sizeof(range_state));
474
475 /* Write the range: */
476 for (i = 0; i < nr_range; i++) {
477 set_var_mtrr_range(&var_state, range[i].start,
478 range[i].end - range[i].start);
479 }
480
481 /* Write the last range: */
482 if (var_state.range_sizek != 0)
483 range_to_mtrr_with_hole(&var_state, 0, 0);
484
485 num_reg = var_state.reg;
486 /* Clear out the extra MTRR's: */
487 while (var_state.reg < num_var_ranges) {
488 save_var_mtrr(var_state.reg, 0, 0, 0);
489 var_state.reg++;
490 }
491
492 return num_reg;
493 }
494
495 struct mtrr_cleanup_result {
496 unsigned long gran_sizek;
497 unsigned long chunk_sizek;
498 unsigned long lose_cover_sizek;
499 unsigned int num_reg;
500 int bad;
501 };
502
503 /*
504 * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G
505 * chunk size: gran_size, ..., 2G
506 * so we need (1+16)*8
507 */
508 #define NUM_RESULT 136
509 #define PSHIFT (PAGE_SHIFT - 10)
510
511 static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
512 static unsigned long __initdata min_loss_pfn[RANGE_NUM];
513
514 static void __init print_out_mtrr_range_state(void)
515 {
516 char start_factor = 'K', size_factor = 'K';
517 unsigned long start_base, size_base;
518 mtrr_type type;
519 int i;
520
521 for (i = 0; i < num_var_ranges; i++) {
522
523 size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10);
524 if (!size_base)
525 continue;
526
527 size_base = to_size_factor(size_base, &size_factor);
528 start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10);
529 start_base = to_size_factor(start_base, &start_factor);
530 type = range_state[i].type;
531
532 Dprintk("reg %d, base: %ld%cB, range: %ld%cB, type %s\n",
533 i, start_base, start_factor,
534 size_base, size_factor,
535 (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
536 ((type == MTRR_TYPE_WRPROT) ? "WP" :
537 ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other"))
538 );
539 }
540 }
541
542 static int __init mtrr_need_cleanup(void)
543 {
544 int i;
545 mtrr_type type;
546 unsigned long size;
547 /* Extra one for all 0: */
548 int num[MTRR_NUM_TYPES + 1];
549
550 /* Check entries number: */
551 memset(num, 0, sizeof(num));
552 for (i = 0; i < num_var_ranges; i++) {
553 type = range_state[i].type;
554 size = range_state[i].size_pfn;
555 if (type >= MTRR_NUM_TYPES)
556 continue;
557 if (!size)
558 type = MTRR_NUM_TYPES;
559 num[type]++;
560 }
561
562 /* Check if we got UC entries: */
563 if (!num[MTRR_TYPE_UNCACHABLE])
564 return 0;
565
566 /* Check if we only had WB and UC */
567 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
568 num_var_ranges - num[MTRR_NUM_TYPES])
569 return 0;
570
571 return 1;
572 }
573
574 static unsigned long __initdata range_sums;
575
576 static void __init
577 mtrr_calc_range_state(u64 chunk_size, u64 gran_size,
578 unsigned long x_remove_base,
579 unsigned long x_remove_size, int i)
580 {
581 /*
582 * range_new should really be an automatic variable, but
583 * putting 4096 bytes on the stack is frowned upon, to put it
584 * mildly. It is safe to make it a static __initdata variable,
585 * since mtrr_calc_range_state is only called during init and
586 * there's no way it will call itself recursively.
587 */
588 static struct range range_new[RANGE_NUM] __initdata;
589 unsigned long range_sums_new;
590 int nr_range_new;
591 int num_reg;
592
593 /* Convert ranges to var ranges state: */
594 num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
595
596 /* We got new setting in range_state, check it: */
597 memset(range_new, 0, sizeof(range_new));
598 nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
599 x_remove_base, x_remove_size);
600 range_sums_new = sum_ranges(range_new, nr_range_new);
601
602 result[i].chunk_sizek = chunk_size >> 10;
603 result[i].gran_sizek = gran_size >> 10;
604 result[i].num_reg = num_reg;
605
606 if (range_sums < range_sums_new) {
607 result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT;
608 result[i].bad = 1;
609 } else {
610 result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT;
611 }
612
613 /* Double check it: */
614 if (!result[i].bad && !result[i].lose_cover_sizek) {
615 if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range)))
616 result[i].bad = 1;
617 }
618
619 if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg]))
620 min_loss_pfn[num_reg] = range_sums - range_sums_new;
621 }
622
623 static void __init mtrr_print_out_one_result(int i)
624 {
625 unsigned long gran_base, chunk_base, lose_base;
626 char gran_factor, chunk_factor, lose_factor;
627
628 gran_base = to_size_factor(result[i].gran_sizek, &gran_factor);
629 chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor);
630 lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor);
631
632 pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t",
633 result[i].bad ? "*BAD*" : " ",
634 gran_base, gran_factor, chunk_base, chunk_factor);
635 pr_cont("num_reg: %d \tlose cover RAM: %s%ld%c\n",
636 result[i].num_reg, result[i].bad ? "-" : "",
637 lose_base, lose_factor);
638 }
639
640 static int __init mtrr_search_optimal_index(void)
641 {
642 int num_reg_good;
643 int index_good;
644 int i;
645
646 if (nr_mtrr_spare_reg >= num_var_ranges)
647 nr_mtrr_spare_reg = num_var_ranges - 1;
648
649 num_reg_good = -1;
650 for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) {
651 if (!min_loss_pfn[i])
652 num_reg_good = i;
653 }
654
655 index_good = -1;
656 if (num_reg_good != -1) {
657 for (i = 0; i < NUM_RESULT; i++) {
658 if (!result[i].bad &&
659 result[i].num_reg == num_reg_good &&
660 !result[i].lose_cover_sizek) {
661 index_good = i;
662 break;
663 }
664 }
665 }
666
667 return index_good;
668 }
669
670 int __init mtrr_cleanup(void)
671 {
672 unsigned long x_remove_base, x_remove_size;
673 unsigned long base, size, def, dummy;
674 u64 chunk_size, gran_size;
675 mtrr_type type;
676 int index_good;
677 int i;
678
679 if (!mtrr_enabled())
680 return 0;
681
682 if (!cpu_feature_enabled(X86_FEATURE_MTRR) || enable_mtrr_cleanup < 1)
683 return 0;
684
685 rdmsr(MSR_MTRRdefType, def, dummy);
686 def &= 0xff;
687 if (def != MTRR_TYPE_UNCACHABLE)
688 return 0;
689
690 /* Get it and store it aside: */
691 memset(range_state, 0, sizeof(range_state));
692 for (i = 0; i < num_var_ranges; i++) {
693 mtrr_if->get(i, &base, &size, &type);
694 range_state[i].base_pfn = base;
695 range_state[i].size_pfn = size;
696 range_state[i].type = type;
697 }
698
699 /* Check if we need handle it and can handle it: */
700 if (!mtrr_need_cleanup())
701 return 0;
702
703 /* Print original var MTRRs at first, for debugging: */
704 Dprintk("original variable MTRRs\n");
705 print_out_mtrr_range_state();
706
707 memset(range, 0, sizeof(range));
708 x_remove_size = 0;
709 x_remove_base = 1 << (32 - PAGE_SHIFT);
710 if (mtrr_tom2)
711 x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base;
712
713 /*
714 * [0, 1M) should always be covered by var mtrr with WB
715 * and fixed mtrrs should take effect before var mtrr for it:
716 */
717 nr_range = add_range_with_merge(range, RANGE_NUM, 0, 0,
718 1ULL<<(20 - PAGE_SHIFT));
719 /* add from var mtrr at last */
720 nr_range = x86_get_mtrr_mem_range(range, nr_range,
721 x_remove_base, x_remove_size);
722
723 range_sums = sum_ranges(range, nr_range);
724 pr_info("total RAM covered: %ldM\n",
725 range_sums >> (20 - PAGE_SHIFT));
726
727 if (mtrr_chunk_size && mtrr_gran_size) {
728 i = 0;
729 mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size,
730 x_remove_base, x_remove_size, i);
731
732 mtrr_print_out_one_result(i);
733
734 if (!result[i].bad) {
735 set_var_mtrr_all();
736 Dprintk("New variable MTRRs\n");
737 print_out_mtrr_range_state();
738 return 1;
739 }
740 pr_info("invalid mtrr_gran_size or mtrr_chunk_size, will find optimal one\n");
741 }
742
743 i = 0;
744 memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
745 memset(result, 0, sizeof(result));
746 for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) {
747
748 for (chunk_size = gran_size; chunk_size < (1ULL<<32);
749 chunk_size <<= 1) {
750
751 if (i >= NUM_RESULT)
752 continue;
753
754 mtrr_calc_range_state(chunk_size, gran_size,
755 x_remove_base, x_remove_size, i);
756 if (mtrr_debug) {
757 mtrr_print_out_one_result(i);
758 pr_info("\n");
759 }
760
761 i++;
762 }
763 }
764
765 /* Try to find the optimal index: */
766 index_good = mtrr_search_optimal_index();
767
768 if (index_good != -1) {
769 pr_info("Found optimal setting for mtrr clean up\n");
770 i = index_good;
771 mtrr_print_out_one_result(i);
772
773 /* Convert ranges to var ranges state: */
774 chunk_size = result[i].chunk_sizek;
775 chunk_size <<= 10;
776 gran_size = result[i].gran_sizek;
777 gran_size <<= 10;
778 x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
779 set_var_mtrr_all();
780 Dprintk("New variable MTRRs\n");
781 print_out_mtrr_range_state();
782 return 1;
783 } else {
784 /* print out all */
785 for (i = 0; i < NUM_RESULT; i++)
786 mtrr_print_out_one_result(i);
787 }
788
789 pr_info("mtrr_cleanup: can not find optimal value\n");
790 pr_info("please specify mtrr_gran_size/mtrr_chunk_size\n");
791
792 return 0;
793 }
794 #else
795 int __init mtrr_cleanup(void)
796 {
797 return 0;
798 }
799 #endif
800
801 static int disable_mtrr_trim;
802
803 static int __init disable_mtrr_trim_setup(char *str)
804 {
805 disable_mtrr_trim = 1;
806 return 0;
807 }
808 early_param("disable_mtrr_trim", disable_mtrr_trim_setup);
809
810 /*
811 * Newer AMD K8s and later CPUs have a special magic MSR way to force WB
812 * for memory >4GB. Check for that here.
813 * Note this won't check if the MTRRs < 4GB where the magic bit doesn't
814 * apply to are wrong, but so far we don't know of any such case in the wild.
815 */
816 #define Tom2Enabled (1U << 21)
817 #define Tom2ForceMemTypeWB (1U << 22)
818
819 int __init amd_special_default_mtrr(void)
820 {
821 u32 l, h;
822
823 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
824 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
825 return 0;
826 if (boot_cpu_data.x86 < 0xf)
827 return 0;
828 /* In case some hypervisor doesn't pass SYSCFG through: */
829 if (rdmsr_safe(MSR_AMD64_SYSCFG, &l, &h) < 0)
830 return 0;
831 /*
832 * Memory between 4GB and top of mem is forced WB by this magic bit.
833 * Reserved before K8RevF, but should be zero there.
834 */
835 if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) ==
836 (Tom2Enabled | Tom2ForceMemTypeWB))
837 return 1;
838 return 0;
839 }
840
841 static u64 __init
842 real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
843 {
844 u64 trim_start, trim_size;
845
846 trim_start = start_pfn;
847 trim_start <<= PAGE_SHIFT;
848
849 trim_size = limit_pfn;
850 trim_size <<= PAGE_SHIFT;
851 trim_size -= trim_start;
852
853 return e820__range_update(trim_start, trim_size, E820_TYPE_RAM, E820_TYPE_RESERVED);
854 }
855
856 /**
857 * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs
858 * @end_pfn: ending page frame number
859 *
860 * Some buggy BIOSes don't setup the MTRRs properly for systems with certain
861 * memory configurations. This routine checks that the highest MTRR matches
862 * the end of memory, to make sure the MTRRs having a write back type cover
863 * all of the memory the kernel is intending to use. If not, it'll trim any
864 * memory off the end by adjusting end_pfn, removing it from the kernel's
865 * allocation pools, warning the user with an obnoxious message.
866 */
867 int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
868 {
869 unsigned long i, base, size, highest_pfn = 0, def, dummy;
870 mtrr_type type;
871 u64 total_trim_size;
872 /* extra one for all 0 */
873 int num[MTRR_NUM_TYPES + 1];
874
875 if (!mtrr_enabled())
876 return 0;
877
878 /*
879 * Make sure we only trim uncachable memory on machines that
880 * support the Intel MTRR architecture:
881 */
882 if (!cpu_feature_enabled(X86_FEATURE_MTRR) || disable_mtrr_trim)
883 return 0;
884
885 rdmsr(MSR_MTRRdefType, def, dummy);
886 def &= MTRR_DEF_TYPE_TYPE;
887 if (def != MTRR_TYPE_UNCACHABLE)
888 return 0;
889
890 /* Get it and store it aside: */
891 memset(range_state, 0, sizeof(range_state));
892 for (i = 0; i < num_var_ranges; i++) {
893 mtrr_if->get(i, &base, &size, &type);
894 range_state[i].base_pfn = base;
895 range_state[i].size_pfn = size;
896 range_state[i].type = type;
897 }
898
899 /* Find highest cached pfn: */
900 for (i = 0; i < num_var_ranges; i++) {
901 type = range_state[i].type;
902 if (type != MTRR_TYPE_WRBACK)
903 continue;
904 base = range_state[i].base_pfn;
905 size = range_state[i].size_pfn;
906 if (highest_pfn < base + size)
907 highest_pfn = base + size;
908 }
909
910 /* kvm/qemu doesn't have mtrr set right, don't trim them all: */
911 if (!highest_pfn) {
912 pr_info("CPU MTRRs all blank - virtualized system.\n");
913 return 0;
914 }
915
916 /* Check entries number: */
917 memset(num, 0, sizeof(num));
918 for (i = 0; i < num_var_ranges; i++) {
919 type = range_state[i].type;
920 if (type >= MTRR_NUM_TYPES)
921 continue;
922 size = range_state[i].size_pfn;
923 if (!size)
924 type = MTRR_NUM_TYPES;
925 num[type]++;
926 }
927
928 /* No entry for WB? */
929 if (!num[MTRR_TYPE_WRBACK])
930 return 0;
931
932 /* Check if we only had WB and UC: */
933 if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
934 num_var_ranges - num[MTRR_NUM_TYPES])
935 return 0;
936
937 memset(range, 0, sizeof(range));
938 nr_range = 0;
939 if (mtrr_tom2) {
940 range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT));
941 range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT;
942 if (highest_pfn < range[nr_range].end)
943 highest_pfn = range[nr_range].end;
944 nr_range++;
945 }
946 nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);
947
948 /* Check the head: */
949 total_trim_size = 0;
950 if (range[0].start)
951 total_trim_size += real_trim_memory(0, range[0].start);
952
953 /* Check the holes: */
954 for (i = 0; i < nr_range - 1; i++) {
955 if (range[i].end < range[i+1].start)
956 total_trim_size += real_trim_memory(range[i].end,
957 range[i+1].start);
958 }
959
960 /* Check the top: */
961 i = nr_range - 1;
962 if (range[i].end < end_pfn)
963 total_trim_size += real_trim_memory(range[i].end,
964 end_pfn);
965
966 if (total_trim_size) {
967 pr_warn("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n",
968 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 e820__update_table_print();
975
976 return 1;
977 }
978
979 return 0;
980 }
Kernel DRM miscellaneous fixes and cross-tree changes