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/memblock.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>
26 #include <asm/iommu.h>
28 #include <asm/pci-direct.h>
30 #include <asm/amd_nb.h>
31 #include <asm/x86_init.h>
34 * Using 512M as goal, in case kexec will load kernel_big
35 * that will do the on-position decompress, and could overlap with
36 * with the gart aperture that is used.
39 * ==> kexec (with kdump trigger path or gart still enabled)
40 * ==> kernel_small (gart area become e820_reserved)
41 * ==> kexec (with kdump trigger path or gart still enabled)
42 * ==> kerne_big (uncompressed size will be big than 64M or 128M)
43 * So don't use 512M below as gart iommu, leave the space for kernel
46 #define GART_MIN_ADDR (512ULL << 20)
47 #define GART_MAX_ADDR (1ULL << 32)
49 int gart_iommu_aperture
;
50 int gart_iommu_aperture_disabled __initdata
;
51 int gart_iommu_aperture_allowed __initdata
;
53 int fallback_aper_order __initdata
= 1; /* 64MB */
54 int fallback_aper_force __initdata
;
56 int fix_aperture __initdata
= 1;
58 static struct resource gart_resource
= {
60 .flags
= IORESOURCE_MEM
,
63 static void __init
insert_aperture_resource(u32 aper_base
, u32 aper_size
)
65 gart_resource
.start
= aper_base
;
66 gart_resource
.end
= aper_base
+ aper_size
- 1;
67 insert_resource(&iomem_resource
, &gart_resource
);
70 /* This code runs before the PCI subsystem is initialized, so just
71 access the northbridge directly. */
73 static u32 __init
allocate_aperture(void)
78 /* aper_size should <= 1G */
79 if (fallback_aper_order
> 5)
80 fallback_aper_order
= 5;
81 aper_size
= (32 * 1024 * 1024) << fallback_aper_order
;
84 * Aperture has to be naturally aligned. This means a 2GB aperture
85 * won't have much chance of finding a place in the lower 4GB of
86 * memory. Unfortunately we cannot move it up because that would
87 * make the IOMMU useless.
89 addr
= memblock_find_in_range(GART_MIN_ADDR
, GART_MAX_ADDR
,
90 aper_size
, aper_size
);
91 if (addr
== MEMBLOCK_ERROR
|| addr
+ aper_size
> GART_MAX_ADDR
) {
93 "Cannot allocate aperture memory hole (%lx,%uK)\n",
97 memblock_x86_reserve_range(addr
, addr
+ aper_size
, "aperture64");
99 * Kmemleak should not scan this block as it may not be mapped via the
100 * kernel direct mapping.
102 kmemleak_ignore(phys_to_virt(addr
));
103 printk(KERN_INFO
"Mapping aperture over %d KB of RAM @ %lx\n",
104 aper_size
>> 10, addr
);
105 insert_aperture_resource((u32
)addr
, aper_size
);
106 register_nosave_region(addr
>> PAGE_SHIFT
,
107 (addr
+aper_size
) >> PAGE_SHIFT
);
113 /* Find a PCI capability */
114 static u32 __init
find_cap(int bus
, int slot
, int func
, int cap
)
119 if (!(read_pci_config_16(bus
, slot
, func
, PCI_STATUS
) &
120 PCI_STATUS_CAP_LIST
))
123 pos
= read_pci_config_byte(bus
, slot
, func
, PCI_CAPABILITY_LIST
);
124 for (bytes
= 0; bytes
< 48 && pos
>= 0x40; bytes
++) {
128 id
= read_pci_config_byte(bus
, slot
, func
, pos
+PCI_CAP_LIST_ID
);
133 pos
= read_pci_config_byte(bus
, slot
, func
,
134 pos
+PCI_CAP_LIST_NEXT
);
139 /* Read a standard AGPv3 bridge header */
140 static u32 __init
read_agp(int bus
, int slot
, int func
, int cap
, u32
*order
)
145 u32 aper_low
, aper_hi
;
149 printk(KERN_INFO
"AGP bridge at %02x:%02x:%02x\n", bus
, slot
, func
);
150 apsizereg
= read_pci_config_16(bus
, slot
, func
, cap
+ 0x14);
151 if (apsizereg
== 0xffffffff) {
152 printk(KERN_ERR
"APSIZE in AGP bridge unreadable\n");
156 /* old_order could be the value from NB gart setting */
159 apsize
= apsizereg
& 0xfff;
160 /* Some BIOS use weird encodings not in the AGPv3 table. */
163 nbits
= hweight16(apsize
);
165 if ((int)*order
< 0) /* < 32MB */
168 aper_low
= read_pci_config(bus
, slot
, func
, 0x10);
169 aper_hi
= read_pci_config(bus
, slot
, func
, 0x14);
170 aper
= (aper_low
& ~((1<<22)-1)) | ((u64
)aper_hi
<< 32);
173 * On some sick chips, APSIZE is 0. It means it wants 4G
174 * so let double check that order, and lets trust AMD NB settings:
176 printk(KERN_INFO
"Aperture from AGP @ %Lx old size %u MB\n",
177 aper
, 32 << old_order
);
178 if (aper
+ (32ULL<<(20 + *order
)) > 0x100000000ULL
) {
179 printk(KERN_INFO
"Aperture size %u MB (APSIZE %x) is not right, using settings from NB\n",
180 32 << *order
, apsizereg
);
184 printk(KERN_INFO
"Aperture from AGP @ %Lx size %u MB (APSIZE %x)\n",
185 aper
, 32 << *order
, apsizereg
);
187 if (!aperture_valid(aper
, (32*1024*1024) << *order
, 32<<20))
193 * Look for an AGP bridge. Windows only expects the aperture in the
194 * AGP bridge and some BIOS forget to initialize the Northbridge too.
195 * Work around this here.
197 * Do an PCI bus scan by hand because we're running before the PCI
200 * All AMD AGP bridges are AGPv3 compliant, so we can do this scan
201 * generically. It's probably overkill to always scan all slots because
202 * the AGP bridges should be always an own bus on the HT hierarchy,
203 * but do it here for future safety.
205 static u32 __init
search_agp_bridge(u32
*order
, int *valid_agp
)
209 /* Poor man's PCI discovery */
210 for (bus
= 0; bus
< 256; bus
++) {
211 for (slot
= 0; slot
< 32; slot
++) {
212 for (func
= 0; func
< 8; func
++) {
215 class = read_pci_config(bus
, slot
, func
,
217 if (class == 0xffffffff)
220 switch (class >> 16) {
221 case PCI_CLASS_BRIDGE_HOST
:
222 case PCI_CLASS_BRIDGE_OTHER
: /* needed? */
224 cap
= find_cap(bus
, slot
, func
,
229 return read_agp(bus
, slot
, func
, cap
,
233 /* No multi-function device? */
234 type
= read_pci_config_byte(bus
, slot
, func
,
241 printk(KERN_INFO
"No AGP bridge found\n");
246 static int gart_fix_e820 __initdata
= 1;
248 static int __init
parse_gart_mem(char *p
)
253 if (!strncmp(p
, "off", 3))
255 else if (!strncmp(p
, "on", 2))
260 early_param("gart_fix_e820", parse_gart_mem
);
262 void __init
early_gart_iommu_check(void)
265 * in case it is enabled before, esp for kexec/kdump,
266 * previous kernel already enable that. memset called
267 * by allocate_aperture/__alloc_bootmem_nopanic cause restart.
268 * or second kernel have different position for GART hole. and new
269 * kernel could use hole as RAM that is still used by GART set by
271 * or BIOS forget to put that in reserved.
272 * try to update e820 to make that region as reserved.
274 u32 agp_aper_order
= 0;
275 int i
, fix
, slot
, valid_agp
= 0;
277 u32 aper_size
= 0, aper_order
= 0, last_aper_order
= 0;
278 u64 aper_base
= 0, last_aper_base
= 0;
279 int aper_enabled
= 0, last_aper_enabled
= 0, last_valid
= 0;
281 if (!early_pci_allowed())
284 /* This is mostly duplicate of iommu_hole_init */
285 search_agp_bridge(&agp_aper_order
, &valid_agp
);
288 for (i
= 0; amd_nb_bus_dev_ranges
[i
].dev_limit
; i
++) {
290 int dev_base
, dev_limit
;
292 bus
= amd_nb_bus_dev_ranges
[i
].bus
;
293 dev_base
= amd_nb_bus_dev_ranges
[i
].dev_base
;
294 dev_limit
= amd_nb_bus_dev_ranges
[i
].dev_limit
;
296 for (slot
= dev_base
; slot
< dev_limit
; slot
++) {
297 if (!early_is_amd_nb(read_pci_config(bus
, slot
, 3, 0x00)))
300 ctl
= read_pci_config(bus
, slot
, 3, AMD64_GARTAPERTURECTL
);
301 aper_enabled
= ctl
& GARTEN
;
302 aper_order
= (ctl
>> 1) & 7;
303 aper_size
= (32 * 1024 * 1024) << aper_order
;
304 aper_base
= read_pci_config(bus
, slot
, 3, AMD64_GARTAPERTUREBASE
) & 0x7fff;
308 if ((aper_order
!= last_aper_order
) ||
309 (aper_base
!= last_aper_base
) ||
310 (aper_enabled
!= last_aper_enabled
)) {
316 last_aper_order
= aper_order
;
317 last_aper_base
= aper_base
;
318 last_aper_enabled
= aper_enabled
;
323 if (!fix
&& !aper_enabled
)
326 if (!aper_base
|| !aper_size
|| aper_base
+ aper_size
> 0x100000000UL
)
329 if (gart_fix_e820
&& !fix
&& aper_enabled
) {
330 if (e820_any_mapped(aper_base
, aper_base
+ aper_size
,
332 /* reserve it, so we can reuse it in second kernel */
333 printk(KERN_INFO
"update e820 for GART\n");
334 e820_add_region(aper_base
, aper_size
, E820_RESERVED
);
342 /* disable them all at first */
343 for (i
= 0; i
< amd_nb_bus_dev_ranges
[i
].dev_limit
; i
++) {
345 int dev_base
, dev_limit
;
347 bus
= amd_nb_bus_dev_ranges
[i
].bus
;
348 dev_base
= amd_nb_bus_dev_ranges
[i
].dev_base
;
349 dev_limit
= amd_nb_bus_dev_ranges
[i
].dev_limit
;
351 for (slot
= dev_base
; slot
< dev_limit
; slot
++) {
352 if (!early_is_amd_nb(read_pci_config(bus
, slot
, 3, 0x00)))
355 ctl
= read_pci_config(bus
, slot
, 3, AMD64_GARTAPERTURECTL
);
357 write_pci_config(bus
, slot
, 3, AMD64_GARTAPERTURECTL
, ctl
);
363 static int __initdata printed_gart_size_msg
;
365 int __init
gart_iommu_hole_init(void)
367 u32 agp_aper_base
= 0, agp_aper_order
= 0;
368 u32 aper_size
, aper_alloc
= 0, aper_order
= 0, last_aper_order
= 0;
369 u64 aper_base
, last_aper_base
= 0;
370 int fix
, slot
, valid_agp
= 0;
373 if (gart_iommu_aperture_disabled
|| !fix_aperture
||
374 !early_pci_allowed())
377 printk(KERN_INFO
"Checking aperture...\n");
379 if (!fallback_aper_force
)
380 agp_aper_base
= search_agp_bridge(&agp_aper_order
, &valid_agp
);
384 for (i
= 0; i
< amd_nb_bus_dev_ranges
[i
].dev_limit
; i
++) {
386 int dev_base
, dev_limit
;
389 bus
= amd_nb_bus_dev_ranges
[i
].bus
;
390 dev_base
= amd_nb_bus_dev_ranges
[i
].dev_base
;
391 dev_limit
= amd_nb_bus_dev_ranges
[i
].dev_limit
;
393 for (slot
= dev_base
; slot
< dev_limit
; slot
++) {
394 if (!early_is_amd_nb(read_pci_config(bus
, slot
, 3, 0x00)))
398 gart_iommu_aperture
= 1;
399 x86_init
.iommu
.iommu_init
= gart_iommu_init
;
401 ctl
= read_pci_config(bus
, slot
, 3,
402 AMD64_GARTAPERTURECTL
);
405 * Before we do anything else disable the GART. It may
406 * still be enabled if we boot into a crash-kernel here.
407 * Reconfiguring the GART while it is enabled could have
408 * unknown side-effects.
411 write_pci_config(bus
, slot
, 3, AMD64_GARTAPERTURECTL
, ctl
);
413 aper_order
= (ctl
>> 1) & 7;
414 aper_size
= (32 * 1024 * 1024) << aper_order
;
415 aper_base
= read_pci_config(bus
, slot
, 3, AMD64_GARTAPERTUREBASE
) & 0x7fff;
418 printk(KERN_INFO
"Node %d: aperture @ %Lx size %u MB\n",
419 node
, aper_base
, aper_size
>> 20);
422 if (!aperture_valid(aper_base
, aper_size
, 64<<20)) {
423 if (valid_agp
&& agp_aper_base
&&
424 agp_aper_base
== aper_base
&&
425 agp_aper_order
== aper_order
) {
426 /* the same between two setting from NB and agp */
428 max_pfn
> MAX_DMA32_PFN
&&
429 !printed_gart_size_msg
) {
430 printk(KERN_ERR
"you are using iommu with agp, but GART size is less than 64M\n");
431 printk(KERN_ERR
"please increase GART size in your BIOS setup\n");
432 printk(KERN_ERR
"if BIOS doesn't have that option, contact your HW vendor!\n");
433 printed_gart_size_msg
= 1;
441 if ((last_aper_order
&& aper_order
!= last_aper_order
) ||
442 (last_aper_base
&& aper_base
!= last_aper_base
)) {
446 last_aper_order
= aper_order
;
447 last_aper_base
= aper_base
;
452 if (!fix
&& !fallback_aper_force
) {
453 if (last_aper_base
) {
454 unsigned long n
= (32 * 1024 * 1024) << last_aper_order
;
456 insert_aperture_resource((u32
)last_aper_base
, n
);
462 if (!fallback_aper_force
) {
463 aper_alloc
= agp_aper_base
;
464 aper_order
= agp_aper_order
;
468 /* Got the aperture from the AGP bridge */
469 } else if ((!no_iommu
&& max_pfn
> MAX_DMA32_PFN
) ||
472 fallback_aper_force
) {
474 "Your BIOS doesn't leave a aperture memory hole\n");
476 "Please enable the IOMMU option in the BIOS setup\n");
478 "This costs you %d MB of RAM\n",
479 32 << fallback_aper_order
);
481 aper_order
= fallback_aper_order
;
482 aper_alloc
= allocate_aperture();
485 * Could disable AGP and IOMMU here, but it's
486 * probably not worth it. But the later users
487 * cannot deal with bad apertures and turning
488 * on the aperture over memory causes very
489 * strange problems, so it's better to panic
492 panic("Not enough memory for aperture");
498 /* Fix up the north bridges */
499 for (i
= 0; i
< amd_nb_bus_dev_ranges
[i
].dev_limit
; i
++) {
500 int bus
, dev_base
, dev_limit
;
503 * Don't enable translation yet but enable GART IO and CPU
504 * accesses and set DISTLBWALKPRB since GART table memory is UC.
506 u32 ctl
= aper_order
<< 1;
508 bus
= amd_nb_bus_dev_ranges
[i
].bus
;
509 dev_base
= amd_nb_bus_dev_ranges
[i
].dev_base
;
510 dev_limit
= amd_nb_bus_dev_ranges
[i
].dev_limit
;
511 for (slot
= dev_base
; slot
< dev_limit
; slot
++) {
512 if (!early_is_amd_nb(read_pci_config(bus
, slot
, 3, 0x00)))
515 write_pci_config(bus
, slot
, 3, AMD64_GARTAPERTURECTL
, ctl
);
516 write_pci_config(bus
, slot
, 3, AMD64_GARTAPERTUREBASE
, aper_alloc
>> 25);
520 set_up_gart_resume(aper_order
, aper_alloc
);