xref: /linux/drivers/char/agp/intel-gtt.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 /*
2  * Intel GTT (Graphics Translation Table) routines
3  *
4  * Caveat: This driver implements the linux agp interface, but this is far from
5  * a agp driver! GTT support ended up here for purely historical reasons: The
6  * old userspace intel graphics drivers needed an interface to map memory into
7  * the GTT. And the drm provides a default interface for graphic devices sitting
8  * on an agp port. So it made sense to fake the GTT support as an agp port to
9  * avoid having to create a new api.
10  *
11  * With gem this does not make much sense anymore, just needlessly complicates
12  * the code. But as long as the old graphics stack is still support, it's stuck
13  * here.
14  *
15  * /fairy-tale-mode off
16  */
17 
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/kernel.h>
21 #include <linux/pagemap.h>
22 #include <linux/agp_backend.h>
23 #include <linux/iommu.h>
24 #include <linux/delay.h>
25 #include <asm/smp.h>
26 #include "agp.h"
27 #include "intel-agp.h"
28 #include <drm/intel/intel-gtt.h>
29 #include <asm/set_memory.h>
30 
31 /*
32  * If we have Intel graphics, we're not going to have anything other than
33  * an Intel IOMMU. So make the correct use of the PCI DMA API contingent
34  * on the Intel IOMMU support (CONFIG_INTEL_IOMMU).
35  * Only newer chipsets need to bother with this, of course.
36  */
37 #ifdef CONFIG_INTEL_IOMMU
38 #define USE_PCI_DMA_API 1
39 #else
40 #define USE_PCI_DMA_API 0
41 #endif
42 
43 struct intel_gtt_driver {
44 	unsigned int gen : 8;
45 	unsigned int is_g33 : 1;
46 	unsigned int is_pineview : 1;
47 	unsigned int is_ironlake : 1;
48 	unsigned int has_pgtbl_enable : 1;
49 	unsigned int dma_mask_size : 8;
50 	/* Chipset specific GTT setup */
51 	int (*setup)(void);
52 	/* This should undo anything done in ->setup() save the unmapping
53 	 * of the mmio register file, that's done in the generic code. */
54 	void (*cleanup)(void);
55 	void (*write_entry)(dma_addr_t addr, unsigned int entry, unsigned int flags);
56 	/* Flags is a more or less chipset specific opaque value.
57 	 * For chipsets that need to support old ums (non-gem) code, this
58 	 * needs to be identical to the various supported agp memory types! */
59 	bool (*check_flags)(unsigned int flags);
60 	void (*chipset_flush)(void);
61 };
62 
63 static struct _intel_private {
64 	const struct intel_gtt_driver *driver;
65 	struct pci_dev *pcidev;	/* device one */
66 	struct pci_dev *bridge_dev;
67 	u8 __iomem *registers;
68 	phys_addr_t gtt_phys_addr;
69 	u32 PGETBL_save;
70 	u32 __iomem *gtt;		/* I915G */
71 	bool clear_fake_agp; /* on first access via agp, fill with scratch */
72 	int num_dcache_entries;
73 	void __iomem *i9xx_flush_page;
74 	char *i81x_gtt_table;
75 	struct resource ifp_resource;
76 	int resource_valid;
77 	struct page *scratch_page;
78 	phys_addr_t scratch_page_dma;
79 	int refcount;
80 	/* Whether i915 needs to use the dmar apis or not. */
81 	unsigned int needs_dmar : 1;
82 	phys_addr_t gma_bus_addr;
83 	/*  Size of memory reserved for graphics by the BIOS */
84 	resource_size_t stolen_size;
85 	/* Total number of gtt entries. */
86 	unsigned int gtt_total_entries;
87 	/* Part of the gtt that is mappable by the cpu, for those chips where
88 	 * this is not the full gtt. */
89 	unsigned int gtt_mappable_entries;
90 } intel_private;
91 
92 #define INTEL_GTT_GEN	intel_private.driver->gen
93 #define IS_G33		intel_private.driver->is_g33
94 #define IS_PINEVIEW	intel_private.driver->is_pineview
95 #define IS_IRONLAKE	intel_private.driver->is_ironlake
96 #define HAS_PGTBL_EN	intel_private.driver->has_pgtbl_enable
97 
98 #if IS_ENABLED(CONFIG_AGP_INTEL)
99 static int intel_gtt_map_memory(struct page **pages,
100 				unsigned int num_entries,
101 				struct sg_table *st)
102 {
103 	struct scatterlist *sg;
104 	int i;
105 
106 	DBG("try mapping %lu pages\n", (unsigned long)num_entries);
107 
108 	if (sg_alloc_table(st, num_entries, GFP_KERNEL))
109 		goto err;
110 
111 	for_each_sg(st->sgl, sg, num_entries, i)
112 		sg_set_page(sg, pages[i], PAGE_SIZE, 0);
113 
114 	if (!dma_map_sg(&intel_private.pcidev->dev, st->sgl, st->nents,
115 			DMA_BIDIRECTIONAL))
116 		goto err;
117 
118 	return 0;
119 
120 err:
121 	sg_free_table(st);
122 	return -ENOMEM;
123 }
124 
125 static void intel_gtt_unmap_memory(struct scatterlist *sg_list, int num_sg)
126 {
127 	struct sg_table st;
128 	DBG("try unmapping %lu pages\n", (unsigned long)mem->page_count);
129 
130 	dma_unmap_sg(&intel_private.pcidev->dev, sg_list, num_sg,
131 		     DMA_BIDIRECTIONAL);
132 
133 	st.sgl = sg_list;
134 	st.orig_nents = st.nents = num_sg;
135 
136 	sg_free_table(&st);
137 }
138 
139 static void intel_fake_agp_enable(struct agp_bridge_data *bridge, u32 mode)
140 {
141 	return;
142 }
143 
144 /* Exists to support ARGB cursors */
145 static struct page *i8xx_alloc_pages(void)
146 {
147 	struct page *page;
148 
149 	page = alloc_pages(GFP_KERNEL | GFP_DMA32, 2);
150 	if (page == NULL)
151 		return NULL;
152 
153 	if (set_pages_uc(page, 4) < 0) {
154 		set_pages_wb(page, 4);
155 		__free_pages(page, 2);
156 		return NULL;
157 	}
158 	atomic_inc(&agp_bridge->current_memory_agp);
159 	return page;
160 }
161 
162 static void i8xx_destroy_pages(struct page *page)
163 {
164 	if (page == NULL)
165 		return;
166 
167 	set_pages_wb(page, 4);
168 	__free_pages(page, 2);
169 	atomic_dec(&agp_bridge->current_memory_agp);
170 }
171 #endif
172 
173 #define I810_GTT_ORDER 4
174 static int i810_setup(void)
175 {
176 	phys_addr_t reg_addr;
177 	char *gtt_table;
178 
179 	/* i81x does not preallocate the gtt. It's always 64kb in size. */
180 	gtt_table = alloc_gatt_pages(I810_GTT_ORDER);
181 	if (gtt_table == NULL)
182 		return -ENOMEM;
183 	intel_private.i81x_gtt_table = gtt_table;
184 
185 	reg_addr = pci_resource_start(intel_private.pcidev, I810_MMADR_BAR);
186 
187 	intel_private.registers = ioremap(reg_addr, KB(64));
188 	if (!intel_private.registers)
189 		return -ENOMEM;
190 
191 	writel(virt_to_phys(gtt_table) | I810_PGETBL_ENABLED,
192 	       intel_private.registers+I810_PGETBL_CTL);
193 
194 	intel_private.gtt_phys_addr = reg_addr + I810_PTE_BASE;
195 
196 	if ((readl(intel_private.registers+I810_DRAM_CTL)
197 		& I810_DRAM_ROW_0) == I810_DRAM_ROW_0_SDRAM) {
198 		dev_info(&intel_private.pcidev->dev,
199 			 "detected 4MB dedicated video ram\n");
200 		intel_private.num_dcache_entries = 1024;
201 	}
202 
203 	return 0;
204 }
205 
206 static void i810_cleanup(void)
207 {
208 	writel(0, intel_private.registers+I810_PGETBL_CTL);
209 	free_gatt_pages(intel_private.i81x_gtt_table, I810_GTT_ORDER);
210 }
211 
212 #if IS_ENABLED(CONFIG_AGP_INTEL)
213 static int i810_insert_dcache_entries(struct agp_memory *mem, off_t pg_start,
214 				      int type)
215 {
216 	int i;
217 
218 	if ((pg_start + mem->page_count)
219 			> intel_private.num_dcache_entries)
220 		return -EINVAL;
221 
222 	if (!mem->is_flushed)
223 		global_cache_flush();
224 
225 	for (i = pg_start; i < (pg_start + mem->page_count); i++) {
226 		dma_addr_t addr = i << PAGE_SHIFT;
227 		intel_private.driver->write_entry(addr,
228 						  i, type);
229 	}
230 	wmb();
231 
232 	return 0;
233 }
234 
235 /*
236  * The i810/i830 requires a physical address to program its mouse
237  * pointer into hardware.
238  * However the Xserver still writes to it through the agp aperture.
239  */
240 static struct agp_memory *alloc_agpphysmem_i8xx(size_t pg_count, int type)
241 {
242 	struct agp_memory *new;
243 	struct page *page;
244 
245 	switch (pg_count) {
246 	case 1: page = agp_bridge->driver->agp_alloc_page(agp_bridge);
247 		break;
248 	case 4:
249 		/* kludge to get 4 physical pages for ARGB cursor */
250 		page = i8xx_alloc_pages();
251 		break;
252 	default:
253 		return NULL;
254 	}
255 
256 	if (page == NULL)
257 		return NULL;
258 
259 	new = agp_create_memory(pg_count);
260 	if (new == NULL)
261 		return NULL;
262 
263 	new->pages[0] = page;
264 	if (pg_count == 4) {
265 		/* kludge to get 4 physical pages for ARGB cursor */
266 		new->pages[1] = new->pages[0] + 1;
267 		new->pages[2] = new->pages[1] + 1;
268 		new->pages[3] = new->pages[2] + 1;
269 	}
270 	new->page_count = pg_count;
271 	new->num_scratch_pages = pg_count;
272 	new->type = AGP_PHYS_MEMORY;
273 	new->physical = page_to_phys(new->pages[0]);
274 	return new;
275 }
276 
277 static void intel_i810_free_by_type(struct agp_memory *curr)
278 {
279 	agp_free_key(curr->key);
280 	if (curr->type == AGP_PHYS_MEMORY) {
281 		if (curr->page_count == 4)
282 			i8xx_destroy_pages(curr->pages[0]);
283 		else {
284 			agp_bridge->driver->agp_destroy_page(curr->pages[0],
285 							     AGP_PAGE_DESTROY_UNMAP);
286 			agp_bridge->driver->agp_destroy_page(curr->pages[0],
287 							     AGP_PAGE_DESTROY_FREE);
288 		}
289 		agp_free_page_array(curr);
290 	}
291 	kfree(curr);
292 }
293 #endif
294 
295 static int intel_gtt_setup_scratch_page(void)
296 {
297 	struct page *page;
298 	dma_addr_t dma_addr;
299 
300 	page = alloc_page(GFP_KERNEL | GFP_DMA32 | __GFP_ZERO);
301 	if (page == NULL)
302 		return -ENOMEM;
303 	set_pages_uc(page, 1);
304 
305 	if (intel_private.needs_dmar) {
306 		dma_addr = dma_map_page(&intel_private.pcidev->dev, page, 0,
307 					PAGE_SIZE, DMA_BIDIRECTIONAL);
308 		if (dma_mapping_error(&intel_private.pcidev->dev, dma_addr)) {
309 			__free_page(page);
310 			return -EINVAL;
311 		}
312 
313 		intel_private.scratch_page_dma = dma_addr;
314 	} else
315 		intel_private.scratch_page_dma = page_to_phys(page);
316 
317 	intel_private.scratch_page = page;
318 
319 	return 0;
320 }
321 
322 static void i810_write_entry(dma_addr_t addr, unsigned int entry,
323 			     unsigned int flags)
324 {
325 	u32 pte_flags = I810_PTE_VALID;
326 
327 	switch (flags) {
328 	case AGP_DCACHE_MEMORY:
329 		pte_flags |= I810_PTE_LOCAL;
330 		break;
331 	case AGP_USER_CACHED_MEMORY:
332 		pte_flags |= I830_PTE_SYSTEM_CACHED;
333 		break;
334 	}
335 
336 	writel_relaxed(addr | pte_flags, intel_private.gtt + entry);
337 }
338 
339 static resource_size_t intel_gtt_stolen_size(void)
340 {
341 	u16 gmch_ctrl;
342 	u8 rdct;
343 	int local = 0;
344 	static const int ddt[4] = { 0, 16, 32, 64 };
345 	resource_size_t stolen_size = 0;
346 
347 	if (INTEL_GTT_GEN == 1)
348 		return 0; /* no stolen mem on i81x */
349 
350 	pci_read_config_word(intel_private.bridge_dev,
351 			     I830_GMCH_CTRL, &gmch_ctrl);
352 
353 	if (intel_private.bridge_dev->device == PCI_DEVICE_ID_INTEL_82830_HB ||
354 	    intel_private.bridge_dev->device == PCI_DEVICE_ID_INTEL_82845G_HB) {
355 		switch (gmch_ctrl & I830_GMCH_GMS_MASK) {
356 		case I830_GMCH_GMS_STOLEN_512:
357 			stolen_size = KB(512);
358 			break;
359 		case I830_GMCH_GMS_STOLEN_1024:
360 			stolen_size = MB(1);
361 			break;
362 		case I830_GMCH_GMS_STOLEN_8192:
363 			stolen_size = MB(8);
364 			break;
365 		case I830_GMCH_GMS_LOCAL:
366 			rdct = readb(intel_private.registers+I830_RDRAM_CHANNEL_TYPE);
367 			stolen_size = (I830_RDRAM_ND(rdct) + 1) *
368 					MB(ddt[I830_RDRAM_DDT(rdct)]);
369 			local = 1;
370 			break;
371 		default:
372 			stolen_size = 0;
373 			break;
374 		}
375 	} else {
376 		switch (gmch_ctrl & I855_GMCH_GMS_MASK) {
377 		case I855_GMCH_GMS_STOLEN_1M:
378 			stolen_size = MB(1);
379 			break;
380 		case I855_GMCH_GMS_STOLEN_4M:
381 			stolen_size = MB(4);
382 			break;
383 		case I855_GMCH_GMS_STOLEN_8M:
384 			stolen_size = MB(8);
385 			break;
386 		case I855_GMCH_GMS_STOLEN_16M:
387 			stolen_size = MB(16);
388 			break;
389 		case I855_GMCH_GMS_STOLEN_32M:
390 			stolen_size = MB(32);
391 			break;
392 		case I915_GMCH_GMS_STOLEN_48M:
393 			stolen_size = MB(48);
394 			break;
395 		case I915_GMCH_GMS_STOLEN_64M:
396 			stolen_size = MB(64);
397 			break;
398 		case G33_GMCH_GMS_STOLEN_128M:
399 			stolen_size = MB(128);
400 			break;
401 		case G33_GMCH_GMS_STOLEN_256M:
402 			stolen_size = MB(256);
403 			break;
404 		case INTEL_GMCH_GMS_STOLEN_96M:
405 			stolen_size = MB(96);
406 			break;
407 		case INTEL_GMCH_GMS_STOLEN_160M:
408 			stolen_size = MB(160);
409 			break;
410 		case INTEL_GMCH_GMS_STOLEN_224M:
411 			stolen_size = MB(224);
412 			break;
413 		case INTEL_GMCH_GMS_STOLEN_352M:
414 			stolen_size = MB(352);
415 			break;
416 		default:
417 			stolen_size = 0;
418 			break;
419 		}
420 	}
421 
422 	if (stolen_size > 0) {
423 		dev_info(&intel_private.bridge_dev->dev, "detected %lluK %s memory\n",
424 		       (u64)stolen_size / KB(1), local ? "local" : "stolen");
425 	} else {
426 		dev_info(&intel_private.bridge_dev->dev,
427 		       "no pre-allocated video memory detected\n");
428 		stolen_size = 0;
429 	}
430 
431 	return stolen_size;
432 }
433 
434 static void i965_adjust_pgetbl_size(unsigned int size_flag)
435 {
436 	u32 pgetbl_ctl, pgetbl_ctl2;
437 
438 	/* ensure that ppgtt is disabled */
439 	pgetbl_ctl2 = readl(intel_private.registers+I965_PGETBL_CTL2);
440 	pgetbl_ctl2 &= ~I810_PGETBL_ENABLED;
441 	writel(pgetbl_ctl2, intel_private.registers+I965_PGETBL_CTL2);
442 
443 	/* write the new ggtt size */
444 	pgetbl_ctl = readl(intel_private.registers+I810_PGETBL_CTL);
445 	pgetbl_ctl &= ~I965_PGETBL_SIZE_MASK;
446 	pgetbl_ctl |= size_flag;
447 	writel(pgetbl_ctl, intel_private.registers+I810_PGETBL_CTL);
448 }
449 
450 static unsigned int i965_gtt_total_entries(void)
451 {
452 	int size;
453 	u32 pgetbl_ctl;
454 	u16 gmch_ctl;
455 
456 	pci_read_config_word(intel_private.bridge_dev,
457 			     I830_GMCH_CTRL, &gmch_ctl);
458 
459 	if (INTEL_GTT_GEN == 5) {
460 		switch (gmch_ctl & G4x_GMCH_SIZE_MASK) {
461 		case G4x_GMCH_SIZE_1M:
462 		case G4x_GMCH_SIZE_VT_1M:
463 			i965_adjust_pgetbl_size(I965_PGETBL_SIZE_1MB);
464 			break;
465 		case G4x_GMCH_SIZE_VT_1_5M:
466 			i965_adjust_pgetbl_size(I965_PGETBL_SIZE_1_5MB);
467 			break;
468 		case G4x_GMCH_SIZE_2M:
469 		case G4x_GMCH_SIZE_VT_2M:
470 			i965_adjust_pgetbl_size(I965_PGETBL_SIZE_2MB);
471 			break;
472 		}
473 	}
474 
475 	pgetbl_ctl = readl(intel_private.registers+I810_PGETBL_CTL);
476 
477 	switch (pgetbl_ctl & I965_PGETBL_SIZE_MASK) {
478 	case I965_PGETBL_SIZE_128KB:
479 		size = KB(128);
480 		break;
481 	case I965_PGETBL_SIZE_256KB:
482 		size = KB(256);
483 		break;
484 	case I965_PGETBL_SIZE_512KB:
485 		size = KB(512);
486 		break;
487 	/* GTT pagetable sizes bigger than 512KB are not possible on G33! */
488 	case I965_PGETBL_SIZE_1MB:
489 		size = KB(1024);
490 		break;
491 	case I965_PGETBL_SIZE_2MB:
492 		size = KB(2048);
493 		break;
494 	case I965_PGETBL_SIZE_1_5MB:
495 		size = KB(1024 + 512);
496 		break;
497 	default:
498 		dev_info(&intel_private.pcidev->dev,
499 			 "unknown page table size, assuming 512KB\n");
500 		size = KB(512);
501 	}
502 
503 	return size/4;
504 }
505 
506 static unsigned int intel_gtt_total_entries(void)
507 {
508 	if (IS_G33 || INTEL_GTT_GEN == 4 || INTEL_GTT_GEN == 5)
509 		return i965_gtt_total_entries();
510 	else {
511 		/* On previous hardware, the GTT size was just what was
512 		 * required to map the aperture.
513 		 */
514 		return intel_private.gtt_mappable_entries;
515 	}
516 }
517 
518 static unsigned int intel_gtt_mappable_entries(void)
519 {
520 	unsigned int aperture_size;
521 
522 	if (INTEL_GTT_GEN == 1) {
523 		u32 smram_miscc;
524 
525 		pci_read_config_dword(intel_private.bridge_dev,
526 				      I810_SMRAM_MISCC, &smram_miscc);
527 
528 		if ((smram_miscc & I810_GFX_MEM_WIN_SIZE)
529 				== I810_GFX_MEM_WIN_32M)
530 			aperture_size = MB(32);
531 		else
532 			aperture_size = MB(64);
533 	} else if (INTEL_GTT_GEN == 2) {
534 		u16 gmch_ctrl;
535 
536 		pci_read_config_word(intel_private.bridge_dev,
537 				     I830_GMCH_CTRL, &gmch_ctrl);
538 
539 		if ((gmch_ctrl & I830_GMCH_MEM_MASK) == I830_GMCH_MEM_64M)
540 			aperture_size = MB(64);
541 		else
542 			aperture_size = MB(128);
543 	} else {
544 		/* 9xx supports large sizes, just look at the length */
545 		aperture_size = pci_resource_len(intel_private.pcidev, 2);
546 	}
547 
548 	return aperture_size >> PAGE_SHIFT;
549 }
550 
551 static void intel_gtt_teardown_scratch_page(void)
552 {
553 	set_pages_wb(intel_private.scratch_page, 1);
554 	if (intel_private.needs_dmar)
555 		dma_unmap_page(&intel_private.pcidev->dev,
556 			       intel_private.scratch_page_dma, PAGE_SIZE,
557 			       DMA_BIDIRECTIONAL);
558 	__free_page(intel_private.scratch_page);
559 }
560 
561 static void intel_gtt_cleanup(void)
562 {
563 	intel_private.driver->cleanup();
564 
565 	iounmap(intel_private.gtt);
566 	iounmap(intel_private.registers);
567 
568 	intel_gtt_teardown_scratch_page();
569 }
570 
571 /* Certain Gen5 chipsets require require idling the GPU before
572  * unmapping anything from the GTT when VT-d is enabled.
573  */
574 static inline int needs_ilk_vtd_wa(void)
575 {
576 	const unsigned short gpu_devid = intel_private.pcidev->device;
577 
578 	/*
579 	 * Query iommu subsystem to see if we need the workaround. Presumably
580 	 * that was loaded first.
581 	 */
582 	return ((gpu_devid == PCI_DEVICE_ID_INTEL_IRONLAKE_D_IG ||
583 		 gpu_devid == PCI_DEVICE_ID_INTEL_IRONLAKE_M_IG) &&
584 		device_iommu_mapped(&intel_private.pcidev->dev));
585 }
586 
587 static bool intel_gtt_can_wc(void)
588 {
589 	if (INTEL_GTT_GEN <= 2)
590 		return false;
591 
592 	if (INTEL_GTT_GEN >= 6)
593 		return false;
594 
595 	/* Reports of major corruption with ILK vt'd enabled */
596 	if (needs_ilk_vtd_wa())
597 		return false;
598 
599 	return true;
600 }
601 
602 static int intel_gtt_init(void)
603 {
604 	u32 gtt_map_size;
605 	int ret, bar;
606 
607 	ret = intel_private.driver->setup();
608 	if (ret != 0)
609 		return ret;
610 
611 	intel_private.gtt_mappable_entries = intel_gtt_mappable_entries();
612 	intel_private.gtt_total_entries = intel_gtt_total_entries();
613 
614 	/* save the PGETBL reg for resume */
615 	intel_private.PGETBL_save =
616 		readl(intel_private.registers+I810_PGETBL_CTL)
617 			& ~I810_PGETBL_ENABLED;
618 	/* we only ever restore the register when enabling the PGTBL... */
619 	if (HAS_PGTBL_EN)
620 		intel_private.PGETBL_save |= I810_PGETBL_ENABLED;
621 
622 	dev_info(&intel_private.bridge_dev->dev,
623 			"detected gtt size: %dK total, %dK mappable\n",
624 			intel_private.gtt_total_entries * 4,
625 			intel_private.gtt_mappable_entries * 4);
626 
627 	gtt_map_size = intel_private.gtt_total_entries * 4;
628 
629 	intel_private.gtt = NULL;
630 	if (intel_gtt_can_wc())
631 		intel_private.gtt = ioremap_wc(intel_private.gtt_phys_addr,
632 					       gtt_map_size);
633 	if (intel_private.gtt == NULL)
634 		intel_private.gtt = ioremap(intel_private.gtt_phys_addr,
635 					    gtt_map_size);
636 	if (intel_private.gtt == NULL) {
637 		intel_private.driver->cleanup();
638 		iounmap(intel_private.registers);
639 		return -ENOMEM;
640 	}
641 
642 #if IS_ENABLED(CONFIG_AGP_INTEL)
643 	global_cache_flush();   /* FIXME: ? */
644 #endif
645 
646 	intel_private.stolen_size = intel_gtt_stolen_size();
647 
648 	intel_private.needs_dmar = USE_PCI_DMA_API && INTEL_GTT_GEN > 2;
649 
650 	ret = intel_gtt_setup_scratch_page();
651 	if (ret != 0) {
652 		intel_gtt_cleanup();
653 		return ret;
654 	}
655 
656 	if (INTEL_GTT_GEN <= 2)
657 		bar = I810_GMADR_BAR;
658 	else
659 		bar = I915_GMADR_BAR;
660 
661 	intel_private.gma_bus_addr = pci_bus_address(intel_private.pcidev, bar);
662 	return 0;
663 }
664 
665 #if IS_ENABLED(CONFIG_AGP_INTEL)
666 static const struct aper_size_info_fixed intel_fake_agp_sizes[] = {
667 	{32, 8192, 3},
668 	{64, 16384, 4},
669 	{128, 32768, 5},
670 	{256, 65536, 6},
671 	{512, 131072, 7},
672 };
673 
674 static int intel_fake_agp_fetch_size(void)
675 {
676 	int num_sizes = ARRAY_SIZE(intel_fake_agp_sizes);
677 	unsigned int aper_size;
678 	int i;
679 
680 	aper_size = (intel_private.gtt_mappable_entries << PAGE_SHIFT) / MB(1);
681 
682 	for (i = 0; i < num_sizes; i++) {
683 		if (aper_size == intel_fake_agp_sizes[i].size) {
684 			agp_bridge->current_size =
685 				(void *) (intel_fake_agp_sizes + i);
686 			return aper_size;
687 		}
688 	}
689 
690 	return 0;
691 }
692 #endif
693 
694 static void i830_cleanup(void)
695 {
696 }
697 
698 /* The chipset_flush interface needs to get data that has already been
699  * flushed out of the CPU all the way out to main memory, because the GPU
700  * doesn't snoop those buffers.
701  *
702  * The 8xx series doesn't have the same lovely interface for flushing the
703  * chipset write buffers that the later chips do. According to the 865
704  * specs, it's 64 octwords, or 1KB.  So, to get those previous things in
705  * that buffer out, we just fill 1KB and clflush it out, on the assumption
706  * that it'll push whatever was in there out.  It appears to work.
707  */
708 static void i830_chipset_flush(void)
709 {
710 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
711 
712 	/* Forcibly evict everything from the CPU write buffers.
713 	 * clflush appears to be insufficient.
714 	 */
715 	wbinvd_on_all_cpus();
716 
717 	/* Now we've only seen documents for this magic bit on 855GM,
718 	 * we hope it exists for the other gen2 chipsets...
719 	 *
720 	 * Also works as advertised on my 845G.
721 	 */
722 	writel(readl(intel_private.registers+I830_HIC) | (1<<31),
723 	       intel_private.registers+I830_HIC);
724 
725 	while (readl(intel_private.registers+I830_HIC) & (1<<31)) {
726 		if (time_after(jiffies, timeout))
727 			break;
728 
729 		udelay(50);
730 	}
731 }
732 
733 static void i830_write_entry(dma_addr_t addr, unsigned int entry,
734 			     unsigned int flags)
735 {
736 	u32 pte_flags = I810_PTE_VALID;
737 
738 	if (flags ==  AGP_USER_CACHED_MEMORY)
739 		pte_flags |= I830_PTE_SYSTEM_CACHED;
740 
741 	writel_relaxed(addr | pte_flags, intel_private.gtt + entry);
742 }
743 
744 bool intel_gmch_enable_gtt(void)
745 {
746 	u8 __iomem *reg;
747 
748 	if (INTEL_GTT_GEN == 2) {
749 		u16 gmch_ctrl;
750 
751 		pci_read_config_word(intel_private.bridge_dev,
752 				     I830_GMCH_CTRL, &gmch_ctrl);
753 		gmch_ctrl |= I830_GMCH_ENABLED;
754 		pci_write_config_word(intel_private.bridge_dev,
755 				      I830_GMCH_CTRL, gmch_ctrl);
756 
757 		pci_read_config_word(intel_private.bridge_dev,
758 				     I830_GMCH_CTRL, &gmch_ctrl);
759 		if ((gmch_ctrl & I830_GMCH_ENABLED) == 0) {
760 			dev_err(&intel_private.pcidev->dev,
761 				"failed to enable the GTT: GMCH_CTRL=%x\n",
762 				gmch_ctrl);
763 			return false;
764 		}
765 	}
766 
767 	/* On the resume path we may be adjusting the PGTBL value, so
768 	 * be paranoid and flush all chipset write buffers...
769 	 */
770 	if (INTEL_GTT_GEN >= 3)
771 		writel(0, intel_private.registers+GFX_FLSH_CNTL);
772 
773 	reg = intel_private.registers+I810_PGETBL_CTL;
774 	writel(intel_private.PGETBL_save, reg);
775 	if (HAS_PGTBL_EN && (readl(reg) & I810_PGETBL_ENABLED) == 0) {
776 		dev_err(&intel_private.pcidev->dev,
777 			"failed to enable the GTT: PGETBL=%x [expected %x]\n",
778 			readl(reg), intel_private.PGETBL_save);
779 		return false;
780 	}
781 
782 	if (INTEL_GTT_GEN >= 3)
783 		writel(0, intel_private.registers+GFX_FLSH_CNTL);
784 
785 	return true;
786 }
787 EXPORT_SYMBOL(intel_gmch_enable_gtt);
788 
789 static int i830_setup(void)
790 {
791 	phys_addr_t reg_addr;
792 
793 	reg_addr = pci_resource_start(intel_private.pcidev, I810_MMADR_BAR);
794 
795 	intel_private.registers = ioremap(reg_addr, KB(64));
796 	if (!intel_private.registers)
797 		return -ENOMEM;
798 
799 	intel_private.gtt_phys_addr = reg_addr + I810_PTE_BASE;
800 
801 	return 0;
802 }
803 
804 #if IS_ENABLED(CONFIG_AGP_INTEL)
805 static int intel_fake_agp_create_gatt_table(struct agp_bridge_data *bridge)
806 {
807 	agp_bridge->gatt_table_real = NULL;
808 	agp_bridge->gatt_table = NULL;
809 	agp_bridge->gatt_bus_addr = 0;
810 
811 	return 0;
812 }
813 
814 static int intel_fake_agp_free_gatt_table(struct agp_bridge_data *bridge)
815 {
816 	return 0;
817 }
818 
819 static int intel_fake_agp_configure(void)
820 {
821 	if (!intel_gmch_enable_gtt())
822 		return -EIO;
823 
824 	intel_private.clear_fake_agp = true;
825 	agp_bridge->gart_bus_addr = intel_private.gma_bus_addr;
826 
827 	return 0;
828 }
829 #endif
830 
831 static bool i830_check_flags(unsigned int flags)
832 {
833 	switch (flags) {
834 	case 0:
835 	case AGP_PHYS_MEMORY:
836 	case AGP_USER_CACHED_MEMORY:
837 	case AGP_USER_MEMORY:
838 		return true;
839 	}
840 
841 	return false;
842 }
843 
844 void intel_gmch_gtt_insert_page(dma_addr_t addr,
845 				unsigned int pg,
846 				unsigned int flags)
847 {
848 	intel_private.driver->write_entry(addr, pg, flags);
849 	readl(intel_private.gtt + pg);
850 	if (intel_private.driver->chipset_flush)
851 		intel_private.driver->chipset_flush();
852 }
853 EXPORT_SYMBOL(intel_gmch_gtt_insert_page);
854 
855 void intel_gmch_gtt_insert_sg_entries(struct sg_table *st,
856 				      unsigned int pg_start,
857 				      unsigned int flags)
858 {
859 	struct scatterlist *sg;
860 	unsigned int len, m;
861 	int i, j;
862 
863 	j = pg_start;
864 
865 	/* sg may merge pages, but we have to separate
866 	 * per-page addr for GTT */
867 	for_each_sg(st->sgl, sg, st->nents, i) {
868 		len = sg_dma_len(sg) >> PAGE_SHIFT;
869 		for (m = 0; m < len; m++) {
870 			dma_addr_t addr = sg_dma_address(sg) + (m << PAGE_SHIFT);
871 			intel_private.driver->write_entry(addr, j, flags);
872 			j++;
873 		}
874 	}
875 	readl(intel_private.gtt + j - 1);
876 	if (intel_private.driver->chipset_flush)
877 		intel_private.driver->chipset_flush();
878 }
879 EXPORT_SYMBOL(intel_gmch_gtt_insert_sg_entries);
880 
881 #if IS_ENABLED(CONFIG_AGP_INTEL)
882 static void intel_gmch_gtt_insert_pages(unsigned int first_entry,
883 					unsigned int num_entries,
884 					struct page **pages,
885 					unsigned int flags)
886 {
887 	int i, j;
888 
889 	for (i = 0, j = first_entry; i < num_entries; i++, j++) {
890 		dma_addr_t addr = page_to_phys(pages[i]);
891 		intel_private.driver->write_entry(addr,
892 						  j, flags);
893 	}
894 	wmb();
895 }
896 
897 static int intel_fake_agp_insert_entries(struct agp_memory *mem,
898 					 off_t pg_start, int type)
899 {
900 	int ret = -EINVAL;
901 
902 	if (intel_private.clear_fake_agp) {
903 		int start = intel_private.stolen_size / PAGE_SIZE;
904 		int end = intel_private.gtt_mappable_entries;
905 		intel_gmch_gtt_clear_range(start, end - start);
906 		intel_private.clear_fake_agp = false;
907 	}
908 
909 	if (INTEL_GTT_GEN == 1 && type == AGP_DCACHE_MEMORY)
910 		return i810_insert_dcache_entries(mem, pg_start, type);
911 
912 	if (mem->page_count == 0)
913 		goto out;
914 
915 	if (pg_start + mem->page_count > intel_private.gtt_total_entries)
916 		goto out_err;
917 
918 	if (type != mem->type)
919 		goto out_err;
920 
921 	if (!intel_private.driver->check_flags(type))
922 		goto out_err;
923 
924 	if (!mem->is_flushed)
925 		global_cache_flush();
926 
927 	if (intel_private.needs_dmar) {
928 		struct sg_table st;
929 
930 		ret = intel_gtt_map_memory(mem->pages, mem->page_count, &st);
931 		if (ret != 0)
932 			return ret;
933 
934 		intel_gmch_gtt_insert_sg_entries(&st, pg_start, type);
935 		mem->sg_list = st.sgl;
936 		mem->num_sg = st.nents;
937 	} else
938 		intel_gmch_gtt_insert_pages(pg_start, mem->page_count, mem->pages,
939 					    type);
940 
941 out:
942 	ret = 0;
943 out_err:
944 	mem->is_flushed = true;
945 	return ret;
946 }
947 #endif
948 
949 void intel_gmch_gtt_clear_range(unsigned int first_entry, unsigned int num_entries)
950 {
951 	unsigned int i;
952 
953 	for (i = first_entry; i < (first_entry + num_entries); i++) {
954 		intel_private.driver->write_entry(intel_private.scratch_page_dma,
955 						  i, 0);
956 	}
957 	wmb();
958 }
959 EXPORT_SYMBOL(intel_gmch_gtt_clear_range);
960 
961 #if IS_ENABLED(CONFIG_AGP_INTEL)
962 static int intel_fake_agp_remove_entries(struct agp_memory *mem,
963 					 off_t pg_start, int type)
964 {
965 	if (mem->page_count == 0)
966 		return 0;
967 
968 	intel_gmch_gtt_clear_range(pg_start, mem->page_count);
969 
970 	if (intel_private.needs_dmar) {
971 		intel_gtt_unmap_memory(mem->sg_list, mem->num_sg);
972 		mem->sg_list = NULL;
973 		mem->num_sg = 0;
974 	}
975 
976 	return 0;
977 }
978 
979 static struct agp_memory *intel_fake_agp_alloc_by_type(size_t pg_count,
980 						       int type)
981 {
982 	struct agp_memory *new;
983 
984 	if (type == AGP_DCACHE_MEMORY && INTEL_GTT_GEN == 1) {
985 		if (pg_count != intel_private.num_dcache_entries)
986 			return NULL;
987 
988 		new = agp_create_memory(1);
989 		if (new == NULL)
990 			return NULL;
991 
992 		new->type = AGP_DCACHE_MEMORY;
993 		new->page_count = pg_count;
994 		new->num_scratch_pages = 0;
995 		agp_free_page_array(new);
996 		return new;
997 	}
998 	if (type == AGP_PHYS_MEMORY)
999 		return alloc_agpphysmem_i8xx(pg_count, type);
1000 	/* always return NULL for other allocation types for now */
1001 	return NULL;
1002 }
1003 #endif
1004 
1005 static int intel_alloc_chipset_flush_resource(void)
1006 {
1007 	int ret;
1008 	ret = pci_bus_alloc_resource(intel_private.bridge_dev->bus, &intel_private.ifp_resource, PAGE_SIZE,
1009 				     PAGE_SIZE, PCIBIOS_MIN_MEM, 0,
1010 				     pcibios_align_resource, intel_private.bridge_dev);
1011 
1012 	return ret;
1013 }
1014 
1015 static void intel_i915_setup_chipset_flush(void)
1016 {
1017 	int ret;
1018 	u32 temp;
1019 
1020 	pci_read_config_dword(intel_private.bridge_dev, I915_IFPADDR, &temp);
1021 	if (!(temp & 0x1)) {
1022 		intel_alloc_chipset_flush_resource();
1023 		intel_private.resource_valid = 1;
1024 		pci_write_config_dword(intel_private.bridge_dev, I915_IFPADDR, (intel_private.ifp_resource.start & 0xffffffff) | 0x1);
1025 	} else {
1026 		temp &= ~1;
1027 
1028 		intel_private.resource_valid = 1;
1029 		intel_private.ifp_resource.start = temp;
1030 		intel_private.ifp_resource.end = temp + PAGE_SIZE;
1031 		ret = request_resource(&iomem_resource, &intel_private.ifp_resource);
1032 		/* some BIOSes reserve this area in a pnp some don't */
1033 		if (ret)
1034 			intel_private.resource_valid = 0;
1035 	}
1036 }
1037 
1038 static void intel_i965_g33_setup_chipset_flush(void)
1039 {
1040 	u32 temp_hi, temp_lo;
1041 	int ret;
1042 
1043 	pci_read_config_dword(intel_private.bridge_dev, I965_IFPADDR + 4, &temp_hi);
1044 	pci_read_config_dword(intel_private.bridge_dev, I965_IFPADDR, &temp_lo);
1045 
1046 	if (!(temp_lo & 0x1)) {
1047 
1048 		intel_alloc_chipset_flush_resource();
1049 
1050 		intel_private.resource_valid = 1;
1051 		pci_write_config_dword(intel_private.bridge_dev, I965_IFPADDR + 4,
1052 			upper_32_bits(intel_private.ifp_resource.start));
1053 		pci_write_config_dword(intel_private.bridge_dev, I965_IFPADDR, (intel_private.ifp_resource.start & 0xffffffff) | 0x1);
1054 	} else {
1055 		u64 l64;
1056 
1057 		temp_lo &= ~0x1;
1058 		l64 = ((u64)temp_hi << 32) | temp_lo;
1059 
1060 		intel_private.resource_valid = 1;
1061 		intel_private.ifp_resource.start = l64;
1062 		intel_private.ifp_resource.end = l64 + PAGE_SIZE;
1063 		ret = request_resource(&iomem_resource, &intel_private.ifp_resource);
1064 		/* some BIOSes reserve this area in a pnp some don't */
1065 		if (ret)
1066 			intel_private.resource_valid = 0;
1067 	}
1068 }
1069 
1070 static void intel_i9xx_setup_flush(void)
1071 {
1072 	/* return if already configured */
1073 	if (intel_private.ifp_resource.start)
1074 		return;
1075 
1076 	if (INTEL_GTT_GEN == 6)
1077 		return;
1078 
1079 	/* setup a resource for this object */
1080 	intel_private.ifp_resource.name = "Intel Flush Page";
1081 	intel_private.ifp_resource.flags = IORESOURCE_MEM;
1082 
1083 	/* Setup chipset flush for 915 */
1084 	if (IS_G33 || INTEL_GTT_GEN >= 4) {
1085 		intel_i965_g33_setup_chipset_flush();
1086 	} else {
1087 		intel_i915_setup_chipset_flush();
1088 	}
1089 
1090 	if (intel_private.ifp_resource.start)
1091 		intel_private.i9xx_flush_page = ioremap(intel_private.ifp_resource.start, PAGE_SIZE);
1092 	if (!intel_private.i9xx_flush_page)
1093 		dev_err(&intel_private.pcidev->dev,
1094 			"can't ioremap flush page - no chipset flushing\n");
1095 }
1096 
1097 static void i9xx_cleanup(void)
1098 {
1099 	if (intel_private.i9xx_flush_page)
1100 		iounmap(intel_private.i9xx_flush_page);
1101 	if (intel_private.resource_valid)
1102 		release_resource(&intel_private.ifp_resource);
1103 	intel_private.ifp_resource.start = 0;
1104 	intel_private.resource_valid = 0;
1105 }
1106 
1107 static void i9xx_chipset_flush(void)
1108 {
1109 	wmb();
1110 	if (intel_private.i9xx_flush_page)
1111 		writel(1, intel_private.i9xx_flush_page);
1112 }
1113 
1114 static void i965_write_entry(dma_addr_t addr,
1115 			     unsigned int entry,
1116 			     unsigned int flags)
1117 {
1118 	u32 pte_flags;
1119 
1120 	pte_flags = I810_PTE_VALID;
1121 	if (flags == AGP_USER_CACHED_MEMORY)
1122 		pte_flags |= I830_PTE_SYSTEM_CACHED;
1123 
1124 	/* Shift high bits down */
1125 	addr |= (addr >> 28) & 0xf0;
1126 	writel_relaxed(addr | pte_flags, intel_private.gtt + entry);
1127 }
1128 
1129 static int i9xx_setup(void)
1130 {
1131 	phys_addr_t reg_addr;
1132 	int size = KB(512);
1133 
1134 	reg_addr = pci_resource_start(intel_private.pcidev, I915_MMADR_BAR);
1135 
1136 	intel_private.registers = ioremap(reg_addr, size);
1137 	if (!intel_private.registers)
1138 		return -ENOMEM;
1139 
1140 	switch (INTEL_GTT_GEN) {
1141 	case 3:
1142 		intel_private.gtt_phys_addr =
1143 			pci_resource_start(intel_private.pcidev, I915_PTE_BAR);
1144 		break;
1145 	case 5:
1146 		intel_private.gtt_phys_addr = reg_addr + MB(2);
1147 		break;
1148 	default:
1149 		intel_private.gtt_phys_addr = reg_addr + KB(512);
1150 		break;
1151 	}
1152 
1153 	intel_i9xx_setup_flush();
1154 
1155 	return 0;
1156 }
1157 
1158 #if IS_ENABLED(CONFIG_AGP_INTEL)
1159 static const struct agp_bridge_driver intel_fake_agp_driver = {
1160 	.owner			= THIS_MODULE,
1161 	.size_type		= FIXED_APER_SIZE,
1162 	.aperture_sizes		= intel_fake_agp_sizes,
1163 	.num_aperture_sizes	= ARRAY_SIZE(intel_fake_agp_sizes),
1164 	.configure		= intel_fake_agp_configure,
1165 	.fetch_size		= intel_fake_agp_fetch_size,
1166 	.cleanup		= intel_gtt_cleanup,
1167 	.agp_enable		= intel_fake_agp_enable,
1168 	.cache_flush		= global_cache_flush,
1169 	.create_gatt_table	= intel_fake_agp_create_gatt_table,
1170 	.free_gatt_table	= intel_fake_agp_free_gatt_table,
1171 	.insert_memory		= intel_fake_agp_insert_entries,
1172 	.remove_memory		= intel_fake_agp_remove_entries,
1173 	.alloc_by_type		= intel_fake_agp_alloc_by_type,
1174 	.free_by_type		= intel_i810_free_by_type,
1175 	.agp_alloc_page		= agp_generic_alloc_page,
1176 	.agp_alloc_pages        = agp_generic_alloc_pages,
1177 	.agp_destroy_page	= agp_generic_destroy_page,
1178 	.agp_destroy_pages      = agp_generic_destroy_pages,
1179 };
1180 #endif
1181 
1182 static const struct intel_gtt_driver i81x_gtt_driver = {
1183 	.gen = 1,
1184 	.has_pgtbl_enable = 1,
1185 	.dma_mask_size = 32,
1186 	.setup = i810_setup,
1187 	.cleanup = i810_cleanup,
1188 	.check_flags = i830_check_flags,
1189 	.write_entry = i810_write_entry,
1190 };
1191 static const struct intel_gtt_driver i8xx_gtt_driver = {
1192 	.gen = 2,
1193 	.has_pgtbl_enable = 1,
1194 	.setup = i830_setup,
1195 	.cleanup = i830_cleanup,
1196 	.write_entry = i830_write_entry,
1197 	.dma_mask_size = 32,
1198 	.check_flags = i830_check_flags,
1199 	.chipset_flush = i830_chipset_flush,
1200 };
1201 static const struct intel_gtt_driver i915_gtt_driver = {
1202 	.gen = 3,
1203 	.has_pgtbl_enable = 1,
1204 	.setup = i9xx_setup,
1205 	.cleanup = i9xx_cleanup,
1206 	/* i945 is the last gpu to need phys mem (for overlay and cursors). */
1207 	.write_entry = i830_write_entry,
1208 	.dma_mask_size = 32,
1209 	.check_flags = i830_check_flags,
1210 	.chipset_flush = i9xx_chipset_flush,
1211 };
1212 static const struct intel_gtt_driver g33_gtt_driver = {
1213 	.gen = 3,
1214 	.is_g33 = 1,
1215 	.setup = i9xx_setup,
1216 	.cleanup = i9xx_cleanup,
1217 	.write_entry = i965_write_entry,
1218 	.dma_mask_size = 36,
1219 	.check_flags = i830_check_flags,
1220 	.chipset_flush = i9xx_chipset_flush,
1221 };
1222 static const struct intel_gtt_driver pineview_gtt_driver = {
1223 	.gen = 3,
1224 	.is_pineview = 1, .is_g33 = 1,
1225 	.setup = i9xx_setup,
1226 	.cleanup = i9xx_cleanup,
1227 	.write_entry = i965_write_entry,
1228 	.dma_mask_size = 36,
1229 	.check_flags = i830_check_flags,
1230 	.chipset_flush = i9xx_chipset_flush,
1231 };
1232 static const struct intel_gtt_driver i965_gtt_driver = {
1233 	.gen = 4,
1234 	.has_pgtbl_enable = 1,
1235 	.setup = i9xx_setup,
1236 	.cleanup = i9xx_cleanup,
1237 	.write_entry = i965_write_entry,
1238 	.dma_mask_size = 36,
1239 	.check_flags = i830_check_flags,
1240 	.chipset_flush = i9xx_chipset_flush,
1241 };
1242 static const struct intel_gtt_driver g4x_gtt_driver = {
1243 	.gen = 5,
1244 	.setup = i9xx_setup,
1245 	.cleanup = i9xx_cleanup,
1246 	.write_entry = i965_write_entry,
1247 	.dma_mask_size = 36,
1248 	.check_flags = i830_check_flags,
1249 	.chipset_flush = i9xx_chipset_flush,
1250 };
1251 static const struct intel_gtt_driver ironlake_gtt_driver = {
1252 	.gen = 5,
1253 	.is_ironlake = 1,
1254 	.setup = i9xx_setup,
1255 	.cleanup = i9xx_cleanup,
1256 	.write_entry = i965_write_entry,
1257 	.dma_mask_size = 36,
1258 	.check_flags = i830_check_flags,
1259 	.chipset_flush = i9xx_chipset_flush,
1260 };
1261 
1262 /* Table to describe Intel GMCH and AGP/PCIE GART drivers.  At least one of
1263  * driver and gmch_driver must be non-null, and find_gmch will determine
1264  * which one should be used if a gmch_chip_id is present.
1265  */
1266 static const struct intel_gtt_driver_description {
1267 	unsigned int gmch_chip_id;
1268 	char *name;
1269 	const struct intel_gtt_driver *gtt_driver;
1270 } intel_gtt_chipsets[] = {
1271 	{ PCI_DEVICE_ID_INTEL_82810_IG1, "i810",
1272 		&i81x_gtt_driver},
1273 	{ PCI_DEVICE_ID_INTEL_82810_IG3, "i810",
1274 		&i81x_gtt_driver},
1275 	{ PCI_DEVICE_ID_INTEL_82810E_IG, "i810",
1276 		&i81x_gtt_driver},
1277 	{ PCI_DEVICE_ID_INTEL_82815_CGC, "i815",
1278 		&i81x_gtt_driver},
1279 	{ PCI_DEVICE_ID_INTEL_82830_CGC, "830M",
1280 		&i8xx_gtt_driver},
1281 	{ PCI_DEVICE_ID_INTEL_82845G_IG, "845G",
1282 		&i8xx_gtt_driver},
1283 	{ PCI_DEVICE_ID_INTEL_82854_IG, "854",
1284 		&i8xx_gtt_driver},
1285 	{ PCI_DEVICE_ID_INTEL_82855GM_IG, "855GM",
1286 		&i8xx_gtt_driver},
1287 	{ PCI_DEVICE_ID_INTEL_82865_IG, "865",
1288 		&i8xx_gtt_driver},
1289 	{ PCI_DEVICE_ID_INTEL_E7221_IG, "E7221 (i915)",
1290 		&i915_gtt_driver },
1291 	{ PCI_DEVICE_ID_INTEL_82915G_IG, "915G",
1292 		&i915_gtt_driver },
1293 	{ PCI_DEVICE_ID_INTEL_82915GM_IG, "915GM",
1294 		&i915_gtt_driver },
1295 	{ PCI_DEVICE_ID_INTEL_82945G_IG, "945G",
1296 		&i915_gtt_driver },
1297 	{ PCI_DEVICE_ID_INTEL_82945GM_IG, "945GM",
1298 		&i915_gtt_driver },
1299 	{ PCI_DEVICE_ID_INTEL_82945GME_IG, "945GME",
1300 		&i915_gtt_driver },
1301 	{ PCI_DEVICE_ID_INTEL_82946GZ_IG, "946GZ",
1302 		&i965_gtt_driver },
1303 	{ PCI_DEVICE_ID_INTEL_82G35_IG, "G35",
1304 		&i965_gtt_driver },
1305 	{ PCI_DEVICE_ID_INTEL_82965Q_IG, "965Q",
1306 		&i965_gtt_driver },
1307 	{ PCI_DEVICE_ID_INTEL_82965G_IG, "965G",
1308 		&i965_gtt_driver },
1309 	{ PCI_DEVICE_ID_INTEL_82965GM_IG, "965GM",
1310 		&i965_gtt_driver },
1311 	{ PCI_DEVICE_ID_INTEL_82965GME_IG, "965GME/GLE",
1312 		&i965_gtt_driver },
1313 	{ PCI_DEVICE_ID_INTEL_G33_IG, "G33",
1314 		&g33_gtt_driver },
1315 	{ PCI_DEVICE_ID_INTEL_Q35_IG, "Q35",
1316 		&g33_gtt_driver },
1317 	{ PCI_DEVICE_ID_INTEL_Q33_IG, "Q33",
1318 		&g33_gtt_driver },
1319 	{ PCI_DEVICE_ID_INTEL_PINEVIEW_M_IG, "GMA3150",
1320 		&pineview_gtt_driver },
1321 	{ PCI_DEVICE_ID_INTEL_PINEVIEW_IG, "GMA3150",
1322 		&pineview_gtt_driver },
1323 	{ PCI_DEVICE_ID_INTEL_GM45_IG, "GM45",
1324 		&g4x_gtt_driver },
1325 	{ PCI_DEVICE_ID_INTEL_EAGLELAKE_IG, "Eaglelake",
1326 		&g4x_gtt_driver },
1327 	{ PCI_DEVICE_ID_INTEL_Q45_IG, "Q45/Q43",
1328 		&g4x_gtt_driver },
1329 	{ PCI_DEVICE_ID_INTEL_G45_IG, "G45/G43",
1330 		&g4x_gtt_driver },
1331 	{ PCI_DEVICE_ID_INTEL_B43_IG, "B43",
1332 		&g4x_gtt_driver },
1333 	{ PCI_DEVICE_ID_INTEL_B43_1_IG, "B43",
1334 		&g4x_gtt_driver },
1335 	{ PCI_DEVICE_ID_INTEL_G41_IG, "G41",
1336 		&g4x_gtt_driver },
1337 	{ PCI_DEVICE_ID_INTEL_IRONLAKE_D_IG,
1338 	    "HD Graphics", &ironlake_gtt_driver },
1339 	{ PCI_DEVICE_ID_INTEL_IRONLAKE_M_IG,
1340 	    "HD Graphics", &ironlake_gtt_driver },
1341 	{ 0, NULL, NULL }
1342 };
1343 
1344 static int find_gmch(u16 device)
1345 {
1346 	struct pci_dev *gmch_device;
1347 
1348 	gmch_device = pci_get_device(PCI_VENDOR_ID_INTEL, device, NULL);
1349 	if (gmch_device && PCI_FUNC(gmch_device->devfn) != 0) {
1350 		gmch_device = pci_get_device(PCI_VENDOR_ID_INTEL,
1351 					     device, gmch_device);
1352 	}
1353 
1354 	if (!gmch_device)
1355 		return 0;
1356 
1357 	intel_private.pcidev = gmch_device;
1358 	return 1;
1359 }
1360 
1361 int intel_gmch_probe(struct pci_dev *bridge_pdev, struct pci_dev *gpu_pdev,
1362 		     struct agp_bridge_data *bridge)
1363 {
1364 	int i, mask;
1365 
1366 	for (i = 0; intel_gtt_chipsets[i].name != NULL; i++) {
1367 		if (gpu_pdev) {
1368 			if (gpu_pdev->device ==
1369 			    intel_gtt_chipsets[i].gmch_chip_id) {
1370 				intel_private.pcidev = pci_dev_get(gpu_pdev);
1371 				intel_private.driver =
1372 					intel_gtt_chipsets[i].gtt_driver;
1373 
1374 				break;
1375 			}
1376 		} else if (find_gmch(intel_gtt_chipsets[i].gmch_chip_id)) {
1377 			intel_private.driver =
1378 				intel_gtt_chipsets[i].gtt_driver;
1379 			break;
1380 		}
1381 	}
1382 
1383 	if (!intel_private.driver)
1384 		return 0;
1385 
1386 #if IS_ENABLED(CONFIG_AGP_INTEL)
1387 	if (bridge) {
1388 		if (INTEL_GTT_GEN > 1)
1389 			return 0;
1390 
1391 		bridge->driver = &intel_fake_agp_driver;
1392 		bridge->dev_private_data = &intel_private;
1393 		bridge->dev = bridge_pdev;
1394 	}
1395 #endif
1396 
1397 
1398 	/*
1399 	 * Can be called from the fake agp driver but also directly from
1400 	 * drm/i915.ko. Hence we need to check whether everything is set up
1401 	 * already.
1402 	 */
1403 	if (intel_private.refcount++)
1404 		return 1;
1405 
1406 	intel_private.bridge_dev = pci_dev_get(bridge_pdev);
1407 
1408 	dev_info(&bridge_pdev->dev, "Intel %s Chipset\n", intel_gtt_chipsets[i].name);
1409 
1410 	if (bridge) {
1411 		mask = intel_private.driver->dma_mask_size;
1412 		if (dma_set_mask(&intel_private.pcidev->dev, DMA_BIT_MASK(mask)))
1413 			dev_err(&intel_private.pcidev->dev,
1414 				"set gfx device dma mask %d-bit failed!\n",
1415 				mask);
1416 		else
1417 			dma_set_coherent_mask(&intel_private.pcidev->dev,
1418 					      DMA_BIT_MASK(mask));
1419 	}
1420 
1421 	if (intel_gtt_init() != 0) {
1422 		intel_gmch_remove();
1423 
1424 		return 0;
1425 	}
1426 
1427 	return 1;
1428 }
1429 EXPORT_SYMBOL(intel_gmch_probe);
1430 
1431 void intel_gmch_gtt_get(u64 *gtt_total,
1432 			phys_addr_t *mappable_base,
1433 			resource_size_t *mappable_end)
1434 {
1435 	*gtt_total = intel_private.gtt_total_entries << PAGE_SHIFT;
1436 	*mappable_base = intel_private.gma_bus_addr;
1437 	*mappable_end = intel_private.gtt_mappable_entries << PAGE_SHIFT;
1438 }
1439 EXPORT_SYMBOL(intel_gmch_gtt_get);
1440 
1441 void intel_gmch_gtt_flush(void)
1442 {
1443 	if (intel_private.driver->chipset_flush)
1444 		intel_private.driver->chipset_flush();
1445 }
1446 EXPORT_SYMBOL(intel_gmch_gtt_flush);
1447 
1448 void intel_gmch_remove(void)
1449 {
1450 	if (--intel_private.refcount)
1451 		return;
1452 
1453 	if (intel_private.scratch_page)
1454 		intel_gtt_teardown_scratch_page();
1455 	if (intel_private.pcidev)
1456 		pci_dev_put(intel_private.pcidev);
1457 	if (intel_private.bridge_dev)
1458 		pci_dev_put(intel_private.bridge_dev);
1459 	intel_private.driver = NULL;
1460 }
1461 EXPORT_SYMBOL(intel_gmch_remove);
1462 
1463 MODULE_AUTHOR("Dave Jones, Various @Intel");
1464 MODULE_DESCRIPTION("Intel GTT (Graphics Translation Table) routines");
1465 MODULE_LICENSE("GPL and additional rights");
1466