2 * Copyright 2001-2003 SuSE Labs.
3 * Distributed under the GNU public license, v2.
5 * This is a GART driver for the AMD Opteron/Athlon64 on-CPU northbridge.
6 * It also includes support for the AMD 8151 AGP bridge,
7 * although it doesn't actually do much, as all the real
8 * work is done in the northbridge(s).
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/init.h>
14 #include <linux/agp_backend.h>
15 #include <linux/mmzone.h>
16 #include <asm/page.h> /* PAGE_SIZE */
23 #define GPTE_COHERENT 2
25 /* Aperture control register bits. */
27 #define DISGARTCPU (1<<4)
28 #define DISGARTIO (1<<5)
30 /* GART cache control register bits. */
31 #define INVGART (1<<0)
32 #define GARTPTEERR (1<<1)
34 /* K8 On-cpu GART registers */
35 #define AMD64_GARTAPERTURECTL 0x90
36 #define AMD64_GARTAPERTUREBASE 0x94
37 #define AMD64_GARTTABLEBASE 0x98
38 #define AMD64_GARTCACHECTL 0x9c
39 #define AMD64_GARTEN (1<<0)
41 /* NVIDIA K8 registers */
42 #define NVIDIA_X86_64_0_APBASE 0x10
43 #define NVIDIA_X86_64_1_APBASE1 0x50
44 #define NVIDIA_X86_64_1_APLIMIT1 0x54
45 #define NVIDIA_X86_64_1_APSIZE 0xa8
46 #define NVIDIA_X86_64_1_APBASE2 0xd8
47 #define NVIDIA_X86_64_1_APLIMIT2 0xdc
49 /* ULi K8 registers */
50 #define ULI_X86_64_BASE_ADDR 0x10
51 #define ULI_X86_64_HTT_FEA_REG 0x50
52 #define ULI_X86_64_ENU_SCR_REG 0x54
54 static struct resource *aperture_resource;
55 static int __initdata agp_try_unsupported = 1;
57 static void amd64_tlbflush(struct agp_memory *temp)
62 static int amd64_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
64 int i, j, num_entries;
67 struct agp_bridge_data *bridge = mem->bridge;
70 num_entries = agp_num_entries();
72 if (type != mem->type)
74 mask_type = bridge->driver->agp_type_to_mask_type(bridge, type);
79 /* Make sure we can fit the range in the gatt table. */
80 /* FIXME: could wrap */
81 if (((unsigned long)pg_start + mem->page_count) > num_entries)
86 /* gatt table should be empty. */
87 while (j < (pg_start + mem->page_count)) {
88 if (!PGE_EMPTY(agp_bridge, readl(agp_bridge->gatt_table+j)))
93 if (mem->is_flushed == FALSE) {
95 mem->is_flushed = TRUE;
98 for (i = 0, j = pg_start; i < mem->page_count; i++, j++) {
99 tmp = agp_bridge->driver->mask_memory(agp_bridge,
100 mem->memory[i], mask_type);
102 BUG_ON(tmp & 0xffffff0000000ffcULL);
103 pte = (tmp & 0x000000ff00000000ULL) >> 28;
104 pte |=(tmp & 0x00000000fffff000ULL);
105 pte |= GPTE_VALID | GPTE_COHERENT;
107 writel(pte, agp_bridge->gatt_table+j);
108 readl(agp_bridge->gatt_table+j); /* PCI Posting. */
115 * This hack alters the order element according
116 * to the size of a long. It sucks. I totally disown this, even
117 * though it does appear to work for the most part.
119 static struct aper_size_info_32 amd64_aperture_sizes[7] =
121 {32, 8192, 3+(sizeof(long)/8), 0 },
122 {64, 16384, 4+(sizeof(long)/8), 1<<1 },
123 {128, 32768, 5+(sizeof(long)/8), 1<<2 },
124 {256, 65536, 6+(sizeof(long)/8), 1<<1 | 1<<2 },
125 {512, 131072, 7+(sizeof(long)/8), 1<<3 },
126 {1024, 262144, 8+(sizeof(long)/8), 1<<1 | 1<<3},
127 {2048, 524288, 9+(sizeof(long)/8), 1<<2 | 1<<3}
132 * Get the current Aperture size from the x86-64.
133 * Note, that there may be multiple x86-64's, but we just return
134 * the value from the first one we find. The set_size functions
135 * keep the rest coherent anyway. Or at least should do.
137 static int amd64_fetch_size(void)
142 struct aper_size_info_32 *values;
144 dev = k8_northbridges[0];
148 pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &temp);
150 values = A_SIZE_32(amd64_aperture_sizes);
152 for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {
153 if (temp == values[i].size_value) {
154 agp_bridge->previous_size =
155 agp_bridge->current_size = (void *) (values + i);
157 agp_bridge->aperture_size_idx = i;
158 return values[i].size;
165 * In a multiprocessor x86-64 system, this function gets
166 * called once for each CPU.
168 static u64 amd64_configure (struct pci_dev *hammer, u64 gatt_table)
174 /* Address to map to */
175 pci_read_config_dword (hammer, AMD64_GARTAPERTUREBASE, &tmp);
176 aperturebase = tmp << 25;
177 aper_base = (aperturebase & PCI_BASE_ADDRESS_MEM_MASK);
179 /* address of the mappings table */
180 addr = (u64) gatt_table;
184 pci_write_config_dword (hammer, AMD64_GARTTABLEBASE, tmp);
186 /* Enable GART translation for this hammer. */
187 pci_read_config_dword(hammer, AMD64_GARTAPERTURECTL, &tmp);
189 tmp &= ~(DISGARTCPU | DISGARTIO);
190 pci_write_config_dword(hammer, AMD64_GARTAPERTURECTL, tmp);
196 static const struct aper_size_info_32 amd_8151_sizes[7] =
198 {2048, 524288, 9, 0x00000000 }, /* 0 0 0 0 0 0 */
199 {1024, 262144, 8, 0x00000400 }, /* 1 0 0 0 0 0 */
200 {512, 131072, 7, 0x00000600 }, /* 1 1 0 0 0 0 */
201 {256, 65536, 6, 0x00000700 }, /* 1 1 1 0 0 0 */
202 {128, 32768, 5, 0x00000720 }, /* 1 1 1 1 0 0 */
203 {64, 16384, 4, 0x00000730 }, /* 1 1 1 1 1 0 */
204 {32, 8192, 3, 0x00000738 } /* 1 1 1 1 1 1 */
207 static int amd_8151_configure(void)
209 unsigned long gatt_bus = virt_to_gart(agp_bridge->gatt_table_real);
212 /* Configure AGP regs in each x86-64 host bridge. */
213 for (i = 0; i < num_k8_northbridges; i++) {
214 agp_bridge->gart_bus_addr =
215 amd64_configure(k8_northbridges[i], gatt_bus);
222 static void amd64_cleanup(void)
226 for (i = 0; i < num_k8_northbridges; i++) {
227 struct pci_dev *dev = k8_northbridges[i];
228 /* disable gart translation */
229 pci_read_config_dword (dev, AMD64_GARTAPERTURECTL, &tmp);
230 tmp &= ~AMD64_GARTEN;
231 pci_write_config_dword (dev, AMD64_GARTAPERTURECTL, tmp);
236 static const struct agp_bridge_driver amd_8151_driver = {
237 .owner = THIS_MODULE,
238 .aperture_sizes = amd_8151_sizes,
239 .size_type = U32_APER_SIZE,
240 .num_aperture_sizes = 7,
241 .configure = amd_8151_configure,
242 .fetch_size = amd64_fetch_size,
243 .cleanup = amd64_cleanup,
244 .tlb_flush = amd64_tlbflush,
245 .mask_memory = agp_generic_mask_memory,
247 .agp_enable = agp_generic_enable,
248 .cache_flush = global_cache_flush,
249 .create_gatt_table = agp_generic_create_gatt_table,
250 .free_gatt_table = agp_generic_free_gatt_table,
251 .insert_memory = amd64_insert_memory,
252 .remove_memory = agp_generic_remove_memory,
253 .alloc_by_type = agp_generic_alloc_by_type,
254 .free_by_type = agp_generic_free_by_type,
255 .agp_alloc_page = agp_generic_alloc_page,
256 .agp_destroy_page = agp_generic_destroy_page,
257 .agp_type_to_mask_type = agp_generic_type_to_mask_type,
260 /* Some basic sanity checks for the aperture. */
261 static int __devinit aperture_valid(u64 aper, u32 size)
264 printk(KERN_ERR PFX "No aperture\n");
267 if (size < 32*1024*1024) {
268 printk(KERN_ERR PFX "Aperture too small (%d MB)\n", size>>20);
271 if ((u64)aper + size > 0x100000000ULL) {
272 printk(KERN_ERR PFX "Aperture out of bounds\n");
275 if (e820_any_mapped(aper, aper + size, E820_RAM)) {
276 printk(KERN_ERR PFX "Aperture pointing to RAM\n");
280 /* Request the Aperture. This catches cases when someone else
281 already put a mapping in there - happens with some very broken BIOS
283 Maybe better to use pci_assign_resource/pci_enable_device instead
284 trusting the bridges? */
285 if (!aperture_resource &&
286 !(aperture_resource = request_mem_region(aper, size, "aperture"))) {
287 printk(KERN_ERR PFX "Aperture conflicts with PCI mapping.\n");
294 * W*s centric BIOS sometimes only set up the aperture in the AGP
295 * bridge, not the northbridge. On AMD64 this is handled early
296 * in aperture.c, but when IOMMU is not enabled or we run
297 * on a 32bit kernel this needs to be redone.
298 * Unfortunately it is impossible to fix the aperture here because it's too late
299 * to allocate that much memory. But at least error out cleanly instead of
302 static __devinit int fix_northbridge(struct pci_dev *nb, struct pci_dev *agp,
305 u32 aper_low, aper_hi;
308 u32 nb_order, nb_base;
311 pci_read_config_dword(nb, 0x90, &nb_order);
312 nb_order = (nb_order >> 1) & 7;
313 pci_read_config_dword(nb, 0x94, &nb_base);
314 nb_aper = nb_base << 25;
315 if (aperture_valid(nb_aper, (32*1024*1024)<<nb_order)) {
319 /* Northbridge seems to contain crap. Try the AGP bridge. */
321 pci_read_config_word(agp, cap+0x14, &apsize);
322 if (apsize == 0xffff)
326 /* Some BIOS use weird encodings not in the AGPv3 table. */
329 order = 7 - hweight16(apsize);
331 pci_read_config_dword(agp, 0x10, &aper_low);
332 pci_read_config_dword(agp, 0x14, &aper_hi);
333 aper = (aper_low & ~((1<<22)-1)) | ((u64)aper_hi << 32);
334 printk(KERN_INFO PFX "Aperture from AGP @ %Lx size %u MB\n", aper, 32 << order);
335 if (order < 0 || !aperture_valid(aper, (32*1024*1024)<<order))
338 pci_write_config_dword(nb, 0x90, order << 1);
339 pci_write_config_dword(nb, 0x94, aper >> 25);
344 static __devinit int cache_nbs (struct pci_dev *pdev, u32 cap_ptr)
348 if (cache_k8_northbridges() < 0)
352 for (i = 0; i < num_k8_northbridges; i++) {
353 struct pci_dev *dev = k8_northbridges[i];
354 if (fix_northbridge(dev, pdev, cap_ptr) < 0) {
355 printk(KERN_ERR PFX "No usable aperture found.\n");
357 /* should port this to i386 */
358 printk(KERN_ERR PFX "Consider rebooting with iommu=memaper=2 to get a good aperture.\n");
366 /* Handle AMD 8151 quirks */
367 static void __devinit amd8151_init(struct pci_dev *pdev, struct agp_bridge_data *bridge)
371 switch (pdev->revision) {
372 case 0x01: revstring="A0"; break;
373 case 0x02: revstring="A1"; break;
374 case 0x11: revstring="B0"; break;
375 case 0x12: revstring="B1"; break;
376 case 0x13: revstring="B2"; break;
377 case 0x14: revstring="B3"; break;
378 default: revstring="??"; break;
381 printk (KERN_INFO PFX "Detected AMD 8151 AGP Bridge rev %s\n", revstring);
384 * Work around errata.
385 * Chips before B2 stepping incorrectly reporting v3.5
387 if (pdev->revision < 0x13) {
388 printk (KERN_INFO PFX "Correcting AGP revision (reports 3.5, is really 3.0)\n");
389 bridge->major_version = 3;
390 bridge->minor_version = 0;
395 static const struct aper_size_info_32 uli_sizes[7] =
405 static int __devinit uli_agp_init(struct pci_dev *pdev)
407 u32 httfea,baseaddr,enuscr;
408 struct pci_dev *dev1;
410 unsigned size = amd64_fetch_size();
411 printk(KERN_INFO "Setting up ULi AGP.\n");
412 dev1 = pci_get_slot (pdev->bus,PCI_DEVFN(0,0));
414 printk(KERN_INFO PFX "Detected a ULi chipset, "
415 "but could not fine the secondary device.\n");
419 for (i = 0; i < ARRAY_SIZE(uli_sizes); i++)
420 if (uli_sizes[i].size == size)
423 if (i == ARRAY_SIZE(uli_sizes)) {
424 printk(KERN_INFO PFX "No ULi size found for %d\n", size);
428 /* shadow x86-64 registers into ULi registers */
429 pci_read_config_dword (k8_northbridges[0], AMD64_GARTAPERTUREBASE, &httfea);
431 /* if x86-64 aperture base is beyond 4G, exit here */
432 if ((httfea & 0x7fff) >> (32 - 25))
435 httfea = (httfea& 0x7fff) << 25;
437 pci_read_config_dword(pdev, ULI_X86_64_BASE_ADDR, &baseaddr);
438 baseaddr&= ~PCI_BASE_ADDRESS_MEM_MASK;
440 pci_write_config_dword(pdev, ULI_X86_64_BASE_ADDR, baseaddr);
442 enuscr= httfea+ (size * 1024 * 1024) - 1;
443 pci_write_config_dword(dev1, ULI_X86_64_HTT_FEA_REG, httfea);
444 pci_write_config_dword(dev1, ULI_X86_64_ENU_SCR_REG, enuscr);
451 static const struct aper_size_info_32 nforce3_sizes[5] =
453 {512, 131072, 7, 0x00000000 },
454 {256, 65536, 6, 0x00000008 },
455 {128, 32768, 5, 0x0000000C },
456 {64, 16384, 4, 0x0000000E },
457 {32, 8192, 3, 0x0000000F }
460 /* Handle shadow device of the Nvidia NForce3 */
461 /* CHECK-ME original 2.4 version set up some IORRs. Check if that is needed. */
462 static int nforce3_agp_init(struct pci_dev *pdev)
464 u32 tmp, apbase, apbar, aplimit;
465 struct pci_dev *dev1;
467 unsigned size = amd64_fetch_size();
469 printk(KERN_INFO PFX "Setting up Nforce3 AGP.\n");
471 dev1 = pci_get_slot(pdev->bus, PCI_DEVFN(11, 0));
473 printk(KERN_INFO PFX "agpgart: Detected an NVIDIA "
474 "nForce3 chipset, but could not find "
475 "the secondary device.\n");
479 for (i = 0; i < ARRAY_SIZE(nforce3_sizes); i++)
480 if (nforce3_sizes[i].size == size)
483 if (i == ARRAY_SIZE(nforce3_sizes)) {
484 printk(KERN_INFO PFX "No NForce3 size found for %d\n", size);
488 pci_read_config_dword(dev1, NVIDIA_X86_64_1_APSIZE, &tmp);
490 tmp |= nforce3_sizes[i].size_value;
491 pci_write_config_dword(dev1, NVIDIA_X86_64_1_APSIZE, tmp);
493 /* shadow x86-64 registers into NVIDIA registers */
494 pci_read_config_dword (k8_northbridges[0], AMD64_GARTAPERTUREBASE, &apbase);
496 /* if x86-64 aperture base is beyond 4G, exit here */
497 if ( (apbase & 0x7fff) >> (32 - 25) ) {
498 printk(KERN_INFO PFX "aperture base > 4G\n");
502 apbase = (apbase & 0x7fff) << 25;
504 pci_read_config_dword(pdev, NVIDIA_X86_64_0_APBASE, &apbar);
505 apbar &= ~PCI_BASE_ADDRESS_MEM_MASK;
507 pci_write_config_dword(pdev, NVIDIA_X86_64_0_APBASE, apbar);
509 aplimit = apbase + (size * 1024 * 1024) - 1;
510 pci_write_config_dword(dev1, NVIDIA_X86_64_1_APBASE1, apbase);
511 pci_write_config_dword(dev1, NVIDIA_X86_64_1_APLIMIT1, aplimit);
512 pci_write_config_dword(dev1, NVIDIA_X86_64_1_APBASE2, apbase);
513 pci_write_config_dword(dev1, NVIDIA_X86_64_1_APLIMIT2, aplimit);
520 static int __devinit agp_amd64_probe(struct pci_dev *pdev,
521 const struct pci_device_id *ent)
523 struct agp_bridge_data *bridge;
526 cap_ptr = pci_find_capability(pdev, PCI_CAP_ID_AGP);
530 /* Could check for AGPv3 here */
532 bridge = agp_alloc_bridge();
536 if (pdev->vendor == PCI_VENDOR_ID_AMD &&
537 pdev->device == PCI_DEVICE_ID_AMD_8151_0) {
538 amd8151_init(pdev, bridge);
540 printk(KERN_INFO PFX "Detected AGP bridge %x\n", pdev->devfn);
543 bridge->driver = &amd_8151_driver;
545 bridge->capndx = cap_ptr;
547 /* Fill in the mode register */
548 pci_read_config_dword(pdev, bridge->capndx+PCI_AGP_STATUS, &bridge->mode);
550 if (cache_nbs(pdev, cap_ptr) == -1) {
551 agp_put_bridge(bridge);
555 if (pdev->vendor == PCI_VENDOR_ID_NVIDIA) {
556 int ret = nforce3_agp_init(pdev);
558 agp_put_bridge(bridge);
563 if (pdev->vendor == PCI_VENDOR_ID_AL) {
564 int ret = uli_agp_init(pdev);
566 agp_put_bridge(bridge);
571 pci_set_drvdata(pdev, bridge);
572 return agp_add_bridge(bridge);
575 static void __devexit agp_amd64_remove(struct pci_dev *pdev)
577 struct agp_bridge_data *bridge = pci_get_drvdata(pdev);
579 release_mem_region(virt_to_gart(bridge->gatt_table_real),
580 amd64_aperture_sizes[bridge->aperture_size_idx].size);
581 agp_remove_bridge(bridge);
582 agp_put_bridge(bridge);
587 static int agp_amd64_suspend(struct pci_dev *pdev, pm_message_t state)
589 pci_save_state(pdev);
590 pci_set_power_state(pdev, pci_choose_state(pdev, state));
595 static int agp_amd64_resume(struct pci_dev *pdev)
597 pci_set_power_state(pdev, PCI_D0);
598 pci_restore_state(pdev);
600 if (pdev->vendor == PCI_VENDOR_ID_NVIDIA)
601 nforce3_agp_init(pdev);
603 return amd_8151_configure();
606 #endif /* CONFIG_PM */
608 static struct pci_device_id agp_amd64_pci_table[] = {
610 .class = (PCI_CLASS_BRIDGE_HOST << 8),
612 .vendor = PCI_VENDOR_ID_AMD,
613 .device = PCI_DEVICE_ID_AMD_8151_0,
614 .subvendor = PCI_ANY_ID,
615 .subdevice = PCI_ANY_ID,
619 .class = (PCI_CLASS_BRIDGE_HOST << 8),
621 .vendor = PCI_VENDOR_ID_AL,
622 .device = PCI_DEVICE_ID_AL_M1689,
623 .subvendor = PCI_ANY_ID,
624 .subdevice = PCI_ANY_ID,
628 .class = (PCI_CLASS_BRIDGE_HOST << 8),
630 .vendor = PCI_VENDOR_ID_VIA,
631 .device = PCI_DEVICE_ID_VIA_K8T800PRO_0,
632 .subvendor = PCI_ANY_ID,
633 .subdevice = PCI_ANY_ID,
637 .class = (PCI_CLASS_BRIDGE_HOST << 8),
639 .vendor = PCI_VENDOR_ID_VIA,
640 .device = PCI_DEVICE_ID_VIA_8385_0,
641 .subvendor = PCI_ANY_ID,
642 .subdevice = PCI_ANY_ID,
644 /* VIA K8M800 / K8N800 */
646 .class = (PCI_CLASS_BRIDGE_HOST << 8),
648 .vendor = PCI_VENDOR_ID_VIA,
649 .device = PCI_DEVICE_ID_VIA_8380_0,
650 .subvendor = PCI_ANY_ID,
651 .subdevice = PCI_ANY_ID,
653 /* VIA K8M890 / K8N890 */
655 .class = (PCI_CLASS_BRIDGE_HOST << 8),
657 .vendor = PCI_VENDOR_ID_VIA,
658 .device = PCI_DEVICE_ID_VIA_VT3336,
659 .subvendor = PCI_ANY_ID,
660 .subdevice = PCI_ANY_ID,
664 .class = (PCI_CLASS_BRIDGE_HOST << 8),
666 .vendor = PCI_VENDOR_ID_VIA,
667 .device = PCI_DEVICE_ID_VIA_3238_0,
668 .subvendor = PCI_ANY_ID,
669 .subdevice = PCI_ANY_ID,
671 /* VIA K8T800/K8M800/K8N800 */
673 .class = (PCI_CLASS_BRIDGE_HOST << 8),
675 .vendor = PCI_VENDOR_ID_VIA,
676 .device = PCI_DEVICE_ID_VIA_838X_1,
677 .subvendor = PCI_ANY_ID,
678 .subdevice = PCI_ANY_ID,
682 .class = (PCI_CLASS_BRIDGE_HOST << 8),
684 .vendor = PCI_VENDOR_ID_NVIDIA,
685 .device = PCI_DEVICE_ID_NVIDIA_NFORCE3,
686 .subvendor = PCI_ANY_ID,
687 .subdevice = PCI_ANY_ID,
690 .class = (PCI_CLASS_BRIDGE_HOST << 8),
692 .vendor = PCI_VENDOR_ID_NVIDIA,
693 .device = PCI_DEVICE_ID_NVIDIA_NFORCE3S,
694 .subvendor = PCI_ANY_ID,
695 .subdevice = PCI_ANY_ID,
699 .class = (PCI_CLASS_BRIDGE_HOST << 8),
701 .vendor = PCI_VENDOR_ID_SI,
702 .device = PCI_DEVICE_ID_SI_755,
703 .subvendor = PCI_ANY_ID,
704 .subdevice = PCI_ANY_ID,
708 .class = (PCI_CLASS_BRIDGE_HOST << 8),
710 .vendor = PCI_VENDOR_ID_SI,
711 .device = PCI_DEVICE_ID_SI_760,
712 .subvendor = PCI_ANY_ID,
713 .subdevice = PCI_ANY_ID,
717 .class = (PCI_CLASS_BRIDGE_HOST << 8),
719 .vendor = PCI_VENDOR_ID_AL,
721 .subvendor = PCI_ANY_ID,
722 .subdevice = PCI_ANY_ID,
728 MODULE_DEVICE_TABLE(pci, agp_amd64_pci_table);
730 static struct pci_driver agp_amd64_pci_driver = {
731 .name = "agpgart-amd64",
732 .id_table = agp_amd64_pci_table,
733 .probe = agp_amd64_probe,
734 .remove = agp_amd64_remove,
736 .suspend = agp_amd64_suspend,
737 .resume = agp_amd64_resume,
742 /* Not static due to IOMMU code calling it early. */
743 int __init agp_amd64_init(void)
749 if (pci_register_driver(&agp_amd64_pci_driver) < 0) {
751 if (!agp_try_unsupported && !agp_try_unsupported_boot) {
752 printk(KERN_INFO PFX "No supported AGP bridge found.\n");
754 printk(KERN_INFO PFX "You can try agp_try_unsupported=1\n");
756 printk(KERN_INFO PFX "You can boot with agp=try_unsupported\n");
761 /* First check that we have at least one AMD64 NB */
762 if (!pci_dev_present(k8_nb_ids))
765 /* Look for any AGP bridge */
768 for_each_pci_dev(dev) {
769 if (!pci_find_capability(dev, PCI_CAP_ID_AGP))
771 /* Only one bridge supported right now */
772 if (agp_amd64_probe(dev, NULL) == 0) {
781 static void __exit agp_amd64_cleanup(void)
783 if (aperture_resource)
784 release_resource(aperture_resource);
785 pci_unregister_driver(&agp_amd64_pci_driver);
788 /* On AMD64 the PCI driver needs to initialize this driver early
789 for the IOMMU, so it has to be called via a backdoor. */
791 module_init(agp_amd64_init);
792 module_exit(agp_amd64_cleanup);
795 MODULE_AUTHOR("Dave Jones <davej@codemonkey.org.uk>, Andi Kleen");
796 module_param(agp_try_unsupported, bool, 0);
797 MODULE_LICENSE("GPL");