iommu/amd: Don't use MSI address range for DMA addresses
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / arch / x86 / kernel / aperture_64.c
blobb5d8b0bcf23588a413d5766d160e24ac6c811441
1 /*
2 * Firmware replacement code.
4 * Work around broken BIOSes that don't set an aperture, only set the
5 * aperture in the AGP bridge, or set too small aperture.
7 * If all fails map the aperture over some low memory. This is cheaper than
8 * doing bounce buffering. The memory is lost. This is done at early boot
9 * because only the bootmem allocator can allocate 32+MB.
11 * Copyright 2002 Andi Kleen, SuSE Labs.
13 #include <linux/kernel.h>
14 #include <linux/types.h>
15 #include <linux/init.h>
16 #include <linux/bootmem.h>
17 #include <linux/mmzone.h>
18 #include <linux/pci_ids.h>
19 #include <linux/pci.h>
20 #include <linux/bitops.h>
21 #include <linux/ioport.h>
22 #include <linux/suspend.h>
23 #include <linux/kmemleak.h>
24 #include <asm/e820.h>
25 #include <asm/io.h>
26 #include <asm/iommu.h>
27 #include <asm/gart.h>
28 #include <asm/pci-direct.h>
29 #include <asm/dma.h>
30 #include <asm/k8.h>
31 #include <asm/x86_init.h>
33 int gart_iommu_aperture;
34 int gart_iommu_aperture_disabled __initdata;
35 int gart_iommu_aperture_allowed __initdata;
37 int fallback_aper_order __initdata = 1; /* 64MB */
38 int fallback_aper_force __initdata;
40 int fix_aperture __initdata = 1;
42 struct bus_dev_range {
43 int bus;
44 int dev_base;
45 int dev_limit;
48 static struct bus_dev_range bus_dev_ranges[] __initdata = {
49 { 0x00, 0x18, 0x20},
50 { 0xff, 0x00, 0x20},
51 { 0xfe, 0x00, 0x20}
54 static struct resource gart_resource = {
55 .name = "GART",
56 .flags = IORESOURCE_MEM,
59 static void __init insert_aperture_resource(u32 aper_base, u32 aper_size)
61 gart_resource.start = aper_base;
62 gart_resource.end = aper_base + aper_size - 1;
63 insert_resource(&iomem_resource, &gart_resource);
66 /* This code runs before the PCI subsystem is initialized, so just
67 access the northbridge directly. */
69 static u32 __init allocate_aperture(void)
71 u32 aper_size;
72 void *p;
74 /* aper_size should <= 1G */
75 if (fallback_aper_order > 5)
76 fallback_aper_order = 5;
77 aper_size = (32 * 1024 * 1024) << fallback_aper_order;
80 * Aperture has to be naturally aligned. This means a 2GB aperture
81 * won't have much chance of finding a place in the lower 4GB of
82 * memory. Unfortunately we cannot move it up because that would
83 * make the IOMMU useless.
86 * using 512M as goal, in case kexec will load kernel_big
87 * that will do the on position decompress, and could overlap with
88 * that positon with gart that is used.
89 * sequende:
90 * kernel_small
91 * ==> kexec (with kdump trigger path or previous doesn't shutdown gart)
92 * ==> kernel_small(gart area become e820_reserved)
93 * ==> kexec (with kdump trigger path or previous doesn't shutdown gart)
94 * ==> kerne_big (uncompressed size will be big than 64M or 128M)
95 * so don't use 512M below as gart iommu, leave the space for kernel
96 * code for safe
98 p = __alloc_bootmem_nopanic(aper_size, aper_size, 512ULL<<20);
100 * Kmemleak should not scan this block as it may not be mapped via the
101 * kernel direct mapping.
103 kmemleak_ignore(p);
104 if (!p || __pa(p)+aper_size > 0xffffffff) {
105 printk(KERN_ERR
106 "Cannot allocate aperture memory hole (%p,%uK)\n",
107 p, aper_size>>10);
108 if (p)
109 free_bootmem(__pa(p), aper_size);
110 return 0;
112 printk(KERN_INFO "Mapping aperture over %d KB of RAM @ %lx\n",
113 aper_size >> 10, __pa(p));
114 insert_aperture_resource((u32)__pa(p), aper_size);
115 register_nosave_region((u32)__pa(p) >> PAGE_SHIFT,
116 (u32)__pa(p+aper_size) >> PAGE_SHIFT);
118 return (u32)__pa(p);
122 /* Find a PCI capability */
123 static u32 __init find_cap(int bus, int slot, int func, int cap)
125 int bytes;
126 u8 pos;
128 if (!(read_pci_config_16(bus, slot, func, PCI_STATUS) &
129 PCI_STATUS_CAP_LIST))
130 return 0;
132 pos = read_pci_config_byte(bus, slot, func, PCI_CAPABILITY_LIST);
133 for (bytes = 0; bytes < 48 && pos >= 0x40; bytes++) {
134 u8 id;
136 pos &= ~3;
137 id = read_pci_config_byte(bus, slot, func, pos+PCI_CAP_LIST_ID);
138 if (id == 0xff)
139 break;
140 if (id == cap)
141 return pos;
142 pos = read_pci_config_byte(bus, slot, func,
143 pos+PCI_CAP_LIST_NEXT);
145 return 0;
148 /* Read a standard AGPv3 bridge header */
149 static u32 __init read_agp(int bus, int slot, int func, int cap, u32 *order)
151 u32 apsize;
152 u32 apsizereg;
153 int nbits;
154 u32 aper_low, aper_hi;
155 u64 aper;
156 u32 old_order;
158 printk(KERN_INFO "AGP bridge at %02x:%02x:%02x\n", bus, slot, func);
159 apsizereg = read_pci_config_16(bus, slot, func, cap + 0x14);
160 if (apsizereg == 0xffffffff) {
161 printk(KERN_ERR "APSIZE in AGP bridge unreadable\n");
162 return 0;
165 /* old_order could be the value from NB gart setting */
166 old_order = *order;
168 apsize = apsizereg & 0xfff;
169 /* Some BIOS use weird encodings not in the AGPv3 table. */
170 if (apsize & 0xff)
171 apsize |= 0xf00;
172 nbits = hweight16(apsize);
173 *order = 7 - nbits;
174 if ((int)*order < 0) /* < 32MB */
175 *order = 0;
177 aper_low = read_pci_config(bus, slot, func, 0x10);
178 aper_hi = read_pci_config(bus, slot, func, 0x14);
179 aper = (aper_low & ~((1<<22)-1)) | ((u64)aper_hi << 32);
182 * On some sick chips, APSIZE is 0. It means it wants 4G
183 * so let double check that order, and lets trust AMD NB settings:
185 printk(KERN_INFO "Aperture from AGP @ %Lx old size %u MB\n",
186 aper, 32 << old_order);
187 if (aper + (32ULL<<(20 + *order)) > 0x100000000ULL) {
188 printk(KERN_INFO "Aperture size %u MB (APSIZE %x) is not right, using settings from NB\n",
189 32 << *order, apsizereg);
190 *order = old_order;
193 printk(KERN_INFO "Aperture from AGP @ %Lx size %u MB (APSIZE %x)\n",
194 aper, 32 << *order, apsizereg);
196 if (!aperture_valid(aper, (32*1024*1024) << *order, 32<<20))
197 return 0;
198 return (u32)aper;
202 * Look for an AGP bridge. Windows only expects the aperture in the
203 * AGP bridge and some BIOS forget to initialize the Northbridge too.
204 * Work around this here.
206 * Do an PCI bus scan by hand because we're running before the PCI
207 * subsystem.
209 * All K8 AGP bridges are AGPv3 compliant, so we can do this scan
210 * generically. It's probably overkill to always scan all slots because
211 * the AGP bridges should be always an own bus on the HT hierarchy,
212 * but do it here for future safety.
214 static u32 __init search_agp_bridge(u32 *order, int *valid_agp)
216 int bus, slot, func;
218 /* Poor man's PCI discovery */
219 for (bus = 0; bus < 256; bus++) {
220 for (slot = 0; slot < 32; slot++) {
221 for (func = 0; func < 8; func++) {
222 u32 class, cap;
223 u8 type;
224 class = read_pci_config(bus, slot, func,
225 PCI_CLASS_REVISION);
226 if (class == 0xffffffff)
227 break;
229 switch (class >> 16) {
230 case PCI_CLASS_BRIDGE_HOST:
231 case PCI_CLASS_BRIDGE_OTHER: /* needed? */
232 /* AGP bridge? */
233 cap = find_cap(bus, slot, func,
234 PCI_CAP_ID_AGP);
235 if (!cap)
236 break;
237 *valid_agp = 1;
238 return read_agp(bus, slot, func, cap,
239 order);
242 /* No multi-function device? */
243 type = read_pci_config_byte(bus, slot, func,
244 PCI_HEADER_TYPE);
245 if (!(type & 0x80))
246 break;
250 printk(KERN_INFO "No AGP bridge found\n");
252 return 0;
255 static int gart_fix_e820 __initdata = 1;
257 static int __init parse_gart_mem(char *p)
259 if (!p)
260 return -EINVAL;
262 if (!strncmp(p, "off", 3))
263 gart_fix_e820 = 0;
264 else if (!strncmp(p, "on", 2))
265 gart_fix_e820 = 1;
267 return 0;
269 early_param("gart_fix_e820", parse_gart_mem);
271 void __init early_gart_iommu_check(void)
274 * in case it is enabled before, esp for kexec/kdump,
275 * previous kernel already enable that. memset called
276 * by allocate_aperture/__alloc_bootmem_nopanic cause restart.
277 * or second kernel have different position for GART hole. and new
278 * kernel could use hole as RAM that is still used by GART set by
279 * first kernel
280 * or BIOS forget to put that in reserved.
281 * try to update e820 to make that region as reserved.
283 u32 agp_aper_base = 0, agp_aper_order = 0;
284 int i, fix, slot, valid_agp = 0;
285 u32 ctl;
286 u32 aper_size = 0, aper_order = 0, last_aper_order = 0;
287 u64 aper_base = 0, last_aper_base = 0;
288 int aper_enabled = 0, last_aper_enabled = 0, last_valid = 0;
290 if (!early_pci_allowed())
291 return;
293 /* This is mostly duplicate of iommu_hole_init */
294 agp_aper_base = search_agp_bridge(&agp_aper_order, &valid_agp);
296 fix = 0;
297 for (i = 0; i < ARRAY_SIZE(bus_dev_ranges); i++) {
298 int bus;
299 int dev_base, dev_limit;
301 bus = bus_dev_ranges[i].bus;
302 dev_base = bus_dev_ranges[i].dev_base;
303 dev_limit = bus_dev_ranges[i].dev_limit;
305 for (slot = dev_base; slot < dev_limit; slot++) {
306 if (!early_is_k8_nb(read_pci_config(bus, slot, 3, 0x00)))
307 continue;
309 ctl = read_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL);
310 aper_enabled = ctl & AMD64_GARTEN;
311 aper_order = (ctl >> 1) & 7;
312 aper_size = (32 * 1024 * 1024) << aper_order;
313 aper_base = read_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE) & 0x7fff;
314 aper_base <<= 25;
316 if (last_valid) {
317 if ((aper_order != last_aper_order) ||
318 (aper_base != last_aper_base) ||
319 (aper_enabled != last_aper_enabled)) {
320 fix = 1;
321 break;
325 last_aper_order = aper_order;
326 last_aper_base = aper_base;
327 last_aper_enabled = aper_enabled;
328 last_valid = 1;
332 if (!fix && !aper_enabled)
333 return;
335 if (!aper_base || !aper_size || aper_base + aper_size > 0x100000000UL)
336 fix = 1;
338 if (gart_fix_e820 && !fix && aper_enabled) {
339 if (e820_any_mapped(aper_base, aper_base + aper_size,
340 E820_RAM)) {
341 /* reserve it, so we can reuse it in second kernel */
342 printk(KERN_INFO "update e820 for GART\n");
343 e820_add_region(aper_base, aper_size, E820_RESERVED);
344 update_e820();
348 if (valid_agp)
349 return;
351 /* disable them all at first */
352 for (i = 0; i < ARRAY_SIZE(bus_dev_ranges); i++) {
353 int bus;
354 int dev_base, dev_limit;
356 bus = bus_dev_ranges[i].bus;
357 dev_base = bus_dev_ranges[i].dev_base;
358 dev_limit = bus_dev_ranges[i].dev_limit;
360 for (slot = dev_base; slot < dev_limit; slot++) {
361 if (!early_is_k8_nb(read_pci_config(bus, slot, 3, 0x00)))
362 continue;
364 ctl = read_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL);
365 ctl &= ~AMD64_GARTEN;
366 write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, ctl);
372 static int __initdata printed_gart_size_msg;
374 void __init gart_iommu_hole_init(void)
376 u32 agp_aper_base = 0, agp_aper_order = 0;
377 u32 aper_size, aper_alloc = 0, aper_order = 0, last_aper_order = 0;
378 u64 aper_base, last_aper_base = 0;
379 int fix, slot, valid_agp = 0;
380 int i, node;
382 if (gart_iommu_aperture_disabled || !fix_aperture ||
383 !early_pci_allowed())
384 return;
386 printk(KERN_INFO "Checking aperture...\n");
388 if (!fallback_aper_force)
389 agp_aper_base = search_agp_bridge(&agp_aper_order, &valid_agp);
391 fix = 0;
392 node = 0;
393 for (i = 0; i < ARRAY_SIZE(bus_dev_ranges); i++) {
394 int bus;
395 int dev_base, dev_limit;
396 u32 ctl;
398 bus = bus_dev_ranges[i].bus;
399 dev_base = bus_dev_ranges[i].dev_base;
400 dev_limit = bus_dev_ranges[i].dev_limit;
402 for (slot = dev_base; slot < dev_limit; slot++) {
403 if (!early_is_k8_nb(read_pci_config(bus, slot, 3, 0x00)))
404 continue;
406 iommu_detected = 1;
407 gart_iommu_aperture = 1;
408 x86_init.iommu.iommu_init = gart_iommu_init;
410 ctl = read_pci_config(bus, slot, 3,
411 AMD64_GARTAPERTURECTL);
414 * Before we do anything else disable the GART. It may
415 * still be enabled if we boot into a crash-kernel here.
416 * Reconfiguring the GART while it is enabled could have
417 * unknown side-effects.
419 ctl &= ~GARTEN;
420 write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, ctl);
422 aper_order = (ctl >> 1) & 7;
423 aper_size = (32 * 1024 * 1024) << aper_order;
424 aper_base = read_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE) & 0x7fff;
425 aper_base <<= 25;
427 printk(KERN_INFO "Node %d: aperture @ %Lx size %u MB\n",
428 node, aper_base, aper_size >> 20);
429 node++;
431 if (!aperture_valid(aper_base, aper_size, 64<<20)) {
432 if (valid_agp && agp_aper_base &&
433 agp_aper_base == aper_base &&
434 agp_aper_order == aper_order) {
435 /* the same between two setting from NB and agp */
436 if (!no_iommu &&
437 max_pfn > MAX_DMA32_PFN &&
438 !printed_gart_size_msg) {
439 printk(KERN_ERR "you are using iommu with agp, but GART size is less than 64M\n");
440 printk(KERN_ERR "please increase GART size in your BIOS setup\n");
441 printk(KERN_ERR "if BIOS doesn't have that option, contact your HW vendor!\n");
442 printed_gart_size_msg = 1;
444 } else {
445 fix = 1;
446 goto out;
450 if ((last_aper_order && aper_order != last_aper_order) ||
451 (last_aper_base && aper_base != last_aper_base)) {
452 fix = 1;
453 goto out;
455 last_aper_order = aper_order;
456 last_aper_base = aper_base;
460 out:
461 if (!fix && !fallback_aper_force) {
462 if (last_aper_base) {
463 unsigned long n = (32 * 1024 * 1024) << last_aper_order;
465 insert_aperture_resource((u32)last_aper_base, n);
467 return;
470 if (!fallback_aper_force) {
471 aper_alloc = agp_aper_base;
472 aper_order = agp_aper_order;
475 if (aper_alloc) {
476 /* Got the aperture from the AGP bridge */
477 } else if ((!no_iommu && max_pfn > MAX_DMA32_PFN) ||
478 force_iommu ||
479 valid_agp ||
480 fallback_aper_force) {
481 printk(KERN_INFO
482 "Your BIOS doesn't leave a aperture memory hole\n");
483 printk(KERN_INFO
484 "Please enable the IOMMU option in the BIOS setup\n");
485 printk(KERN_INFO
486 "This costs you %d MB of RAM\n",
487 32 << fallback_aper_order);
489 aper_order = fallback_aper_order;
490 aper_alloc = allocate_aperture();
491 if (!aper_alloc) {
493 * Could disable AGP and IOMMU here, but it's
494 * probably not worth it. But the later users
495 * cannot deal with bad apertures and turning
496 * on the aperture over memory causes very
497 * strange problems, so it's better to panic
498 * early.
500 panic("Not enough memory for aperture");
502 } else {
503 return;
506 /* Fix up the north bridges */
507 for (i = 0; i < ARRAY_SIZE(bus_dev_ranges); i++) {
508 int bus;
509 int dev_base, dev_limit;
511 bus = bus_dev_ranges[i].bus;
512 dev_base = bus_dev_ranges[i].dev_base;
513 dev_limit = bus_dev_ranges[i].dev_limit;
514 for (slot = dev_base; slot < dev_limit; slot++) {
515 if (!early_is_k8_nb(read_pci_config(bus, slot, 3, 0x00)))
516 continue;
518 /* Don't enable translation yet. That is done later.
519 Assume this BIOS didn't initialise the GART so
520 just overwrite all previous bits */
521 write_pci_config(bus, slot, 3, AMD64_GARTAPERTURECTL, aper_order << 1);
522 write_pci_config(bus, slot, 3, AMD64_GARTAPERTUREBASE, aper_alloc >> 25);
526 set_up_gart_resume(aper_order, aper_alloc);