1 /*
2  * Copyright © 2010 Daniel Vetter
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  */
24 
25 #include <drm/drmP.h>
26 #include <drm/i915_drm.h>
27 #include "i915_drv.h"
28 #include "i915_trace.h"
29 #include "intel_drv.h"
30 
31 #define GEN6_PPGTT_PD_ENTRIES 512
32 #define I915_PPGTT_PT_ENTRIES (PAGE_SIZE / sizeof(gen6_gtt_pte_t))
33 typedef uint64_t gen8_gtt_pte_t;
34 typedef gen8_gtt_pte_t gen8_ppgtt_pde_t;
35 
36 /* PPGTT stuff */
37 #define GEN6_GTT_ADDR_ENCODE(addr)	((addr) | (((addr) >> 28) & 0xff0))
38 #define HSW_GTT_ADDR_ENCODE(addr)	((addr) | (((addr) >> 28) & 0x7f0))
39 
40 #define GEN6_PDE_VALID			(1 << 0)
41 /* gen6+ has bit 11-4 for physical addr bit 39-32 */
42 #define GEN6_PDE_ADDR_ENCODE(addr)	GEN6_GTT_ADDR_ENCODE(addr)
43 
44 #define GEN6_PTE_VALID			(1 << 0)
45 #define GEN6_PTE_UNCACHED		(1 << 1)
46 #define HSW_PTE_UNCACHED		(0)
47 #define GEN6_PTE_CACHE_LLC		(2 << 1)
48 #define GEN7_PTE_CACHE_L3_LLC		(3 << 1)
49 #define GEN6_PTE_ADDR_ENCODE(addr)	GEN6_GTT_ADDR_ENCODE(addr)
50 #define HSW_PTE_ADDR_ENCODE(addr)	HSW_GTT_ADDR_ENCODE(addr)
51 
52 /* Cacheability Control is a 4-bit value. The low three bits are stored in *
53  * bits 3:1 of the PTE, while the fourth bit is stored in bit 11 of the PTE.
54  */
55 #define HSW_CACHEABILITY_CONTROL(bits)	((((bits) & 0x7) << 1) | \
56 					 (((bits) & 0x8) << (11 - 3)))
57 #define HSW_WB_LLC_AGE3			HSW_CACHEABILITY_CONTROL(0x2)
58 #define HSW_WB_LLC_AGE0			HSW_CACHEABILITY_CONTROL(0x3)
59 #define HSW_WB_ELLC_LLC_AGE0		HSW_CACHEABILITY_CONTROL(0xb)
60 #define HSW_WT_ELLC_LLC_AGE0		HSW_CACHEABILITY_CONTROL(0x6)
61 
62 #define GEN8_PTES_PER_PAGE		(PAGE_SIZE / sizeof(gen8_gtt_pte_t))
63 #define GEN8_PDES_PER_PAGE		(PAGE_SIZE / sizeof(gen8_ppgtt_pde_t))
64 #define GEN8_LEGACY_PDPS		4
65 
66 #define PPAT_UNCACHED_INDEX		(_PAGE_PWT | _PAGE_PCD)
67 #define PPAT_CACHED_PDE_INDEX		0 /* WB LLC */
68 #define PPAT_CACHED_INDEX		_PAGE_PAT /* WB LLCeLLC */
69 #define PPAT_DISPLAY_ELLC_INDEX		_PAGE_PCD /* WT eLLC */
70 
71 static inline gen8_gtt_pte_t gen8_pte_encode(dma_addr_t addr,
72 					     enum i915_cache_level level,
73 					     bool valid)
74 {
75 	gen8_gtt_pte_t pte = valid ? _PAGE_PRESENT | _PAGE_RW : 0;
76 	pte |= addr;
77 	if (level != I915_CACHE_NONE)
78 		pte |= PPAT_CACHED_INDEX;
79 	else
80 		pte |= PPAT_UNCACHED_INDEX;
81 	return pte;
82 }
83 
84 static inline gen8_ppgtt_pde_t gen8_pde_encode(struct drm_device *dev,
85 					     dma_addr_t addr,
86 					     enum i915_cache_level level)
87 {
88 	gen8_ppgtt_pde_t pde = _PAGE_PRESENT | _PAGE_RW;
89 	pde |= addr;
90 	if (level != I915_CACHE_NONE)
91 		pde |= PPAT_CACHED_PDE_INDEX;
92 	else
93 		pde |= PPAT_UNCACHED_INDEX;
94 	return pde;
95 }
96 
97 static gen6_gtt_pte_t snb_pte_encode(dma_addr_t addr,
98 				     enum i915_cache_level level,
99 				     bool valid)
100 {
101 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
102 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
103 
104 	switch (level) {
105 	case I915_CACHE_L3_LLC:
106 	case I915_CACHE_LLC:
107 		pte |= GEN6_PTE_CACHE_LLC;
108 		break;
109 	case I915_CACHE_NONE:
110 		pte |= GEN6_PTE_UNCACHED;
111 		break;
112 	default:
113 		WARN_ON(1);
114 	}
115 
116 	return pte;
117 }
118 
119 static gen6_gtt_pte_t ivb_pte_encode(dma_addr_t addr,
120 				     enum i915_cache_level level,
121 				     bool valid)
122 {
123 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
124 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
125 
126 	switch (level) {
127 	case I915_CACHE_L3_LLC:
128 		pte |= GEN7_PTE_CACHE_L3_LLC;
129 		break;
130 	case I915_CACHE_LLC:
131 		pte |= GEN6_PTE_CACHE_LLC;
132 		break;
133 	case I915_CACHE_NONE:
134 		pte |= GEN6_PTE_UNCACHED;
135 		break;
136 	default:
137 		WARN_ON(1);
138 	}
139 
140 	return pte;
141 }
142 
143 #define BYT_PTE_WRITEABLE		(1 << 1)
144 #define BYT_PTE_SNOOPED_BY_CPU_CACHES	(1 << 2)
145 
146 static gen6_gtt_pte_t byt_pte_encode(dma_addr_t addr,
147 				     enum i915_cache_level level,
148 				     bool valid)
149 {
150 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
151 	pte |= GEN6_PTE_ADDR_ENCODE(addr);
152 
153 	/* Mark the page as writeable.  Other platforms don't have a
154 	 * setting for read-only/writable, so this matches that behavior.
155 	 */
156 	pte |= BYT_PTE_WRITEABLE;
157 
158 	if (level != I915_CACHE_NONE)
159 		pte |= BYT_PTE_SNOOPED_BY_CPU_CACHES;
160 
161 	return pte;
162 }
163 
164 static gen6_gtt_pte_t hsw_pte_encode(dma_addr_t addr,
165 				     enum i915_cache_level level,
166 				     bool valid)
167 {
168 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
169 	pte |= HSW_PTE_ADDR_ENCODE(addr);
170 
171 	if (level != I915_CACHE_NONE)
172 		pte |= HSW_WB_LLC_AGE3;
173 
174 	return pte;
175 }
176 
177 static gen6_gtt_pte_t iris_pte_encode(dma_addr_t addr,
178 				      enum i915_cache_level level,
179 				      bool valid)
180 {
181 	gen6_gtt_pte_t pte = valid ? GEN6_PTE_VALID : 0;
182 	pte |= HSW_PTE_ADDR_ENCODE(addr);
183 
184 	switch (level) {
185 	case I915_CACHE_NONE:
186 		break;
187 	case I915_CACHE_WT:
188 		pte |= HSW_WT_ELLC_LLC_AGE0;
189 		break;
190 	default:
191 		pte |= HSW_WB_ELLC_LLC_AGE0;
192 		break;
193 	}
194 
195 	return pte;
196 }
197 
198 /* Broadwell Page Directory Pointer Descriptors */
199 static int gen8_write_pdp(struct intel_ring_buffer *ring, unsigned entry,
200 			   uint64_t val)
201 {
202 	int ret;
203 
204 	BUG_ON(entry >= 4);
205 
206 	ret = intel_ring_begin(ring, 6);
207 	if (ret)
208 		return ret;
209 
210 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
211 	intel_ring_emit(ring, GEN8_RING_PDP_UDW(ring, entry));
212 	intel_ring_emit(ring, (u32)(val >> 32));
213 	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
214 	intel_ring_emit(ring, GEN8_RING_PDP_LDW(ring, entry));
215 	intel_ring_emit(ring, (u32)(val));
216 	intel_ring_advance(ring);
217 
218 	return 0;
219 }
220 
221 static int gen8_ppgtt_enable(struct drm_device *dev)
222 {
223 	struct drm_i915_private *dev_priv = dev->dev_private;
224 	struct intel_ring_buffer *ring;
225 	struct i915_hw_ppgtt *ppgtt = dev_priv->mm.aliasing_ppgtt;
226 	int i, j, ret;
227 
228 	/* bit of a hack to find the actual last used pd */
229 	int used_pd = ppgtt->num_pd_entries / GEN8_PDES_PER_PAGE;
230 
231 	for_each_ring(ring, dev_priv, j) {
232 		I915_WRITE(RING_MODE_GEN7(ring),
233 			   _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
234 	}
235 
236 	for (i = used_pd - 1; i >= 0; i--) {
237 		dma_addr_t addr = ppgtt->pd_dma_addr[i];
238 		for_each_ring(ring, dev_priv, j) {
239 			ret = gen8_write_pdp(ring, i, addr);
240 			if (ret)
241 				return ret;
242 		}
243 	}
244 	return 0;
245 }
246 
247 static void gen8_ppgtt_clear_range(struct i915_address_space *vm,
248 				   unsigned first_entry,
249 				   unsigned num_entries,
250 				   bool use_scratch)
251 {
252 	struct i915_hw_ppgtt *ppgtt =
253 		container_of(vm, struct i915_hw_ppgtt, base);
254 	gen8_gtt_pte_t *pt_vaddr, scratch_pte;
255 	unsigned act_pt = first_entry / GEN8_PTES_PER_PAGE;
256 	unsigned first_pte = first_entry % GEN8_PTES_PER_PAGE;
257 	unsigned last_pte, i;
258 
259 	scratch_pte = gen8_pte_encode(ppgtt->base.scratch.addr,
260 				      I915_CACHE_LLC, use_scratch);
261 
262 	while (num_entries) {
263 		struct page *page_table = &ppgtt->gen8_pt_pages[act_pt];
264 
265 		last_pte = first_pte + num_entries;
266 		if (last_pte > GEN8_PTES_PER_PAGE)
267 			last_pte = GEN8_PTES_PER_PAGE;
268 
269 		pt_vaddr = kmap_atomic(page_table);
270 
271 		for (i = first_pte; i < last_pte; i++)
272 			pt_vaddr[i] = scratch_pte;
273 
274 		kunmap_atomic(pt_vaddr);
275 
276 		num_entries -= last_pte - first_pte;
277 		first_pte = 0;
278 		act_pt++;
279 	}
280 }
281 
282 static void gen8_ppgtt_insert_entries(struct i915_address_space *vm,
283 				      struct sg_table *pages,
284 				      unsigned first_entry,
285 				      enum i915_cache_level cache_level)
286 {
287 	struct i915_hw_ppgtt *ppgtt =
288 		container_of(vm, struct i915_hw_ppgtt, base);
289 	gen8_gtt_pte_t *pt_vaddr;
290 	unsigned act_pt = first_entry / GEN8_PTES_PER_PAGE;
291 	unsigned act_pte = first_entry % GEN8_PTES_PER_PAGE;
292 	struct sg_page_iter sg_iter;
293 
294 	pt_vaddr = kmap_atomic(&ppgtt->gen8_pt_pages[act_pt]);
295 	for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
296 		dma_addr_t page_addr;
297 
298 		page_addr = sg_dma_address(sg_iter.sg) +
299 				(sg_iter.sg_pgoffset << PAGE_SHIFT);
300 		pt_vaddr[act_pte] = gen8_pte_encode(page_addr, cache_level,
301 						    true);
302 		if (++act_pte == GEN8_PTES_PER_PAGE) {
303 			kunmap_atomic(pt_vaddr);
304 			act_pt++;
305 			pt_vaddr = kmap_atomic(&ppgtt->gen8_pt_pages[act_pt]);
306 			act_pte = 0;
307 
308 		}
309 	}
310 	kunmap_atomic(pt_vaddr);
311 }
312 
313 static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
314 {
315 	struct i915_hw_ppgtt *ppgtt =
316 		container_of(vm, struct i915_hw_ppgtt, base);
317 	int i, j;
318 
319 	for (i = 0; i < ppgtt->num_pd_pages ; i++) {
320 		if (ppgtt->pd_dma_addr[i]) {
321 			pci_unmap_page(ppgtt->base.dev->pdev,
322 				       ppgtt->pd_dma_addr[i],
323 				       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
324 
325 			for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
326 				dma_addr_t addr = ppgtt->gen8_pt_dma_addr[i][j];
327 				if (addr)
328 					pci_unmap_page(ppgtt->base.dev->pdev,
329 						       addr,
330 						       PAGE_SIZE,
331 						       PCI_DMA_BIDIRECTIONAL);
332 
333 			}
334 		}
335 		kfree(ppgtt->gen8_pt_dma_addr[i]);
336 	}
337 
338 	__free_pages(ppgtt->gen8_pt_pages, ppgtt->num_pt_pages << PAGE_SHIFT);
339 	__free_pages(ppgtt->pd_pages, ppgtt->num_pd_pages << PAGE_SHIFT);
340 }
341 
342 /**
343  * GEN8 legacy ppgtt programming is accomplished through 4 PDP registers with a
344  * net effect resembling a 2-level page table in normal x86 terms. Each PDP
345  * represents 1GB of memory
346  * 4 * 512 * 512 * 4096 = 4GB legacy 32b address space.
347  *
348  * TODO: Do something with the size parameter
349  **/
350 static int gen8_ppgtt_init(struct i915_hw_ppgtt *ppgtt, uint64_t size)
351 {
352 	struct page *pt_pages;
353 	int i, j, ret = -ENOMEM;
354 	const int max_pdp = DIV_ROUND_UP(size, 1 << 30);
355 	const int num_pt_pages = GEN8_PDES_PER_PAGE * max_pdp;
356 
357 	if (size % (1<<30))
358 		DRM_INFO("Pages will be wasted unless GTT size (%llu) is divisible by 1GB\n", size);
359 
360 	/* FIXME: split allocation into smaller pieces. For now we only ever do
361 	 * this once, but with full PPGTT, the multiple contiguous allocations
362 	 * will be bad.
363 	 */
364 	ppgtt->pd_pages = alloc_pages(GFP_KERNEL, get_order(max_pdp << PAGE_SHIFT));
365 	if (!ppgtt->pd_pages)
366 		return -ENOMEM;
367 
368 	pt_pages = alloc_pages(GFP_KERNEL, get_order(num_pt_pages << PAGE_SHIFT));
369 	if (!pt_pages) {
370 		__free_pages(ppgtt->pd_pages, get_order(max_pdp << PAGE_SHIFT));
371 		return -ENOMEM;
372 	}
373 
374 	ppgtt->gen8_pt_pages = pt_pages;
375 	ppgtt->num_pd_pages = 1 << get_order(max_pdp << PAGE_SHIFT);
376 	ppgtt->num_pt_pages = 1 << get_order(num_pt_pages << PAGE_SHIFT);
377 	ppgtt->num_pd_entries = max_pdp * GEN8_PDES_PER_PAGE;
378 	ppgtt->enable = gen8_ppgtt_enable;
379 	ppgtt->base.clear_range = gen8_ppgtt_clear_range;
380 	ppgtt->base.insert_entries = gen8_ppgtt_insert_entries;
381 	ppgtt->base.cleanup = gen8_ppgtt_cleanup;
382 
383 	BUG_ON(ppgtt->num_pd_pages > GEN8_LEGACY_PDPS);
384 
385 	/*
386 	 * - Create a mapping for the page directories.
387 	 * - For each page directory:
388 	 *      allocate space for page table mappings.
389 	 *      map each page table
390 	 */
391 	for (i = 0; i < max_pdp; i++) {
392 		dma_addr_t temp;
393 		temp = pci_map_page(ppgtt->base.dev->pdev,
394 				    &ppgtt->pd_pages[i], 0,
395 				    PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
396 		if (pci_dma_mapping_error(ppgtt->base.dev->pdev, temp))
397 			goto err_out;
398 
399 		ppgtt->pd_dma_addr[i] = temp;
400 
401 		ppgtt->gen8_pt_dma_addr[i] = kmalloc(sizeof(dma_addr_t) * GEN8_PDES_PER_PAGE, GFP_KERNEL);
402 		if (!ppgtt->gen8_pt_dma_addr[i])
403 			goto err_out;
404 
405 		for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
406 			struct page *p = &pt_pages[i * GEN8_PDES_PER_PAGE + j];
407 			temp = pci_map_page(ppgtt->base.dev->pdev,
408 					    p, 0, PAGE_SIZE,
409 					    PCI_DMA_BIDIRECTIONAL);
410 
411 			if (pci_dma_mapping_error(ppgtt->base.dev->pdev, temp))
412 				goto err_out;
413 
414 			ppgtt->gen8_pt_dma_addr[i][j] = temp;
415 		}
416 	}
417 
418 	/* For now, the PPGTT helper functions all require that the PDEs are
419 	 * plugged in correctly. So we do that now/here. For aliasing PPGTT, we
420 	 * will never need to touch the PDEs again */
421 	for (i = 0; i < max_pdp; i++) {
422 		gen8_ppgtt_pde_t *pd_vaddr;
423 		pd_vaddr = kmap_atomic(&ppgtt->pd_pages[i]);
424 		for (j = 0; j < GEN8_PDES_PER_PAGE; j++) {
425 			dma_addr_t addr = ppgtt->gen8_pt_dma_addr[i][j];
426 			pd_vaddr[j] = gen8_pde_encode(ppgtt->base.dev, addr,
427 						      I915_CACHE_LLC);
428 		}
429 		kunmap_atomic(pd_vaddr);
430 	}
431 
432 	ppgtt->base.clear_range(&ppgtt->base, 0,
433 				ppgtt->num_pd_entries * GEN8_PTES_PER_PAGE,
434 				true);
435 
436 	DRM_DEBUG_DRIVER("Allocated %d pages for page directories (%d wasted)\n",
437 			 ppgtt->num_pd_pages, ppgtt->num_pd_pages - max_pdp);
438 	DRM_DEBUG_DRIVER("Allocated %d pages for page tables (%lld wasted)\n",
439 			 ppgtt->num_pt_pages,
440 			 (ppgtt->num_pt_pages - num_pt_pages) +
441 			 size % (1<<30));
442 	return 0;
443 
444 err_out:
445 	ppgtt->base.cleanup(&ppgtt->base);
446 	return ret;
447 }
448 
449 static void gen6_write_pdes(struct i915_hw_ppgtt *ppgtt)
450 {
451 	struct drm_i915_private *dev_priv = ppgtt->base.dev->dev_private;
452 	gen6_gtt_pte_t __iomem *pd_addr;
453 	uint32_t pd_entry;
454 	int i;
455 
456 	WARN_ON(ppgtt->pd_offset & 0x3f);
457 	pd_addr = (gen6_gtt_pte_t __iomem*)dev_priv->gtt.gsm +
458 		ppgtt->pd_offset / sizeof(gen6_gtt_pte_t);
459 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
460 		dma_addr_t pt_addr;
461 
462 		pt_addr = ppgtt->pt_dma_addr[i];
463 		pd_entry = GEN6_PDE_ADDR_ENCODE(pt_addr);
464 		pd_entry |= GEN6_PDE_VALID;
465 
466 		writel(pd_entry, pd_addr + i);
467 	}
468 	readl(pd_addr);
469 }
470 
471 static int gen6_ppgtt_enable(struct drm_device *dev)
472 {
473 	drm_i915_private_t *dev_priv = dev->dev_private;
474 	uint32_t pd_offset;
475 	struct intel_ring_buffer *ring;
476 	struct i915_hw_ppgtt *ppgtt = dev_priv->mm.aliasing_ppgtt;
477 	int i;
478 
479 	BUG_ON(ppgtt->pd_offset & 0x3f);
480 
481 	gen6_write_pdes(ppgtt);
482 
483 	pd_offset = ppgtt->pd_offset;
484 	pd_offset /= 64; /* in cachelines, */
485 	pd_offset <<= 16;
486 
487 	if (INTEL_INFO(dev)->gen == 6) {
488 		uint32_t ecochk, gab_ctl, ecobits;
489 
490 		ecobits = I915_READ(GAC_ECO_BITS);
491 		I915_WRITE(GAC_ECO_BITS, ecobits | ECOBITS_SNB_BIT |
492 					 ECOBITS_PPGTT_CACHE64B);
493 
494 		gab_ctl = I915_READ(GAB_CTL);
495 		I915_WRITE(GAB_CTL, gab_ctl | GAB_CTL_CONT_AFTER_PAGEFAULT);
496 
497 		ecochk = I915_READ(GAM_ECOCHK);
498 		I915_WRITE(GAM_ECOCHK, ecochk | ECOCHK_SNB_BIT |
499 				       ECOCHK_PPGTT_CACHE64B);
500 		I915_WRITE(GFX_MODE, _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
501 	} else if (INTEL_INFO(dev)->gen >= 7) {
502 		uint32_t ecochk, ecobits;
503 
504 		ecobits = I915_READ(GAC_ECO_BITS);
505 		I915_WRITE(GAC_ECO_BITS, ecobits | ECOBITS_PPGTT_CACHE64B);
506 
507 		ecochk = I915_READ(GAM_ECOCHK);
508 		if (IS_HASWELL(dev)) {
509 			ecochk |= ECOCHK_PPGTT_WB_HSW;
510 		} else {
511 			ecochk |= ECOCHK_PPGTT_LLC_IVB;
512 			ecochk &= ~ECOCHK_PPGTT_GFDT_IVB;
513 		}
514 		I915_WRITE(GAM_ECOCHK, ecochk);
515 		/* GFX_MODE is per-ring on gen7+ */
516 	}
517 
518 	for_each_ring(ring, dev_priv, i) {
519 		if (INTEL_INFO(dev)->gen >= 7)
520 			I915_WRITE(RING_MODE_GEN7(ring),
521 				   _MASKED_BIT_ENABLE(GFX_PPGTT_ENABLE));
522 
523 		I915_WRITE(RING_PP_DIR_DCLV(ring), PP_DIR_DCLV_2G);
524 		I915_WRITE(RING_PP_DIR_BASE(ring), pd_offset);
525 	}
526 	return 0;
527 }
528 
529 /* PPGTT support for Sandybdrige/Gen6 and later */
530 static void gen6_ppgtt_clear_range(struct i915_address_space *vm,
531 				   unsigned first_entry,
532 				   unsigned num_entries,
533 				   bool use_scratch)
534 {
535 	struct i915_hw_ppgtt *ppgtt =
536 		container_of(vm, struct i915_hw_ppgtt, base);
537 	gen6_gtt_pte_t *pt_vaddr, scratch_pte;
538 	unsigned act_pt = first_entry / I915_PPGTT_PT_ENTRIES;
539 	unsigned first_pte = first_entry % I915_PPGTT_PT_ENTRIES;
540 	unsigned last_pte, i;
541 
542 	scratch_pte = vm->pte_encode(vm->scratch.addr, I915_CACHE_LLC, true);
543 
544 	while (num_entries) {
545 		last_pte = first_pte + num_entries;
546 		if (last_pte > I915_PPGTT_PT_ENTRIES)
547 			last_pte = I915_PPGTT_PT_ENTRIES;
548 
549 		pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
550 
551 		for (i = first_pte; i < last_pte; i++)
552 			pt_vaddr[i] = scratch_pte;
553 
554 		kunmap_atomic(pt_vaddr);
555 
556 		num_entries -= last_pte - first_pte;
557 		first_pte = 0;
558 		act_pt++;
559 	}
560 }
561 
562 static void gen6_ppgtt_insert_entries(struct i915_address_space *vm,
563 				      struct sg_table *pages,
564 				      unsigned first_entry,
565 				      enum i915_cache_level cache_level)
566 {
567 	struct i915_hw_ppgtt *ppgtt =
568 		container_of(vm, struct i915_hw_ppgtt, base);
569 	gen6_gtt_pte_t *pt_vaddr;
570 	unsigned act_pt = first_entry / I915_PPGTT_PT_ENTRIES;
571 	unsigned act_pte = first_entry % I915_PPGTT_PT_ENTRIES;
572 	struct sg_page_iter sg_iter;
573 
574 	pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
575 	for_each_sg_page(pages->sgl, &sg_iter, pages->nents, 0) {
576 		dma_addr_t page_addr;
577 
578 		page_addr = sg_page_iter_dma_address(&sg_iter);
579 		pt_vaddr[act_pte] = vm->pte_encode(page_addr, cache_level, true);
580 		if (++act_pte == I915_PPGTT_PT_ENTRIES) {
581 			kunmap_atomic(pt_vaddr);
582 			act_pt++;
583 			pt_vaddr = kmap_atomic(ppgtt->pt_pages[act_pt]);
584 			act_pte = 0;
585 
586 		}
587 	}
588 	kunmap_atomic(pt_vaddr);
589 }
590 
591 static void gen6_ppgtt_cleanup(struct i915_address_space *vm)
592 {
593 	struct i915_hw_ppgtt *ppgtt =
594 		container_of(vm, struct i915_hw_ppgtt, base);
595 	int i;
596 
597 	drm_mm_takedown(&ppgtt->base.mm);
598 
599 	if (ppgtt->pt_dma_addr) {
600 		for (i = 0; i < ppgtt->num_pd_entries; i++)
601 			pci_unmap_page(ppgtt->base.dev->pdev,
602 				       ppgtt->pt_dma_addr[i],
603 				       4096, PCI_DMA_BIDIRECTIONAL);
604 	}
605 
606 	kfree(ppgtt->pt_dma_addr);
607 	for (i = 0; i < ppgtt->num_pd_entries; i++)
608 		__free_page(ppgtt->pt_pages[i]);
609 	kfree(ppgtt->pt_pages);
610 	kfree(ppgtt);
611 }
612 
613 static int gen6_ppgtt_init(struct i915_hw_ppgtt *ppgtt)
614 {
615 	struct drm_device *dev = ppgtt->base.dev;
616 	struct drm_i915_private *dev_priv = dev->dev_private;
617 	unsigned first_pd_entry_in_global_pt;
618 	int i;
619 	int ret = -ENOMEM;
620 
621 	/* ppgtt PDEs reside in the global gtt pagetable, which has 512*1024
622 	 * entries. For aliasing ppgtt support we just steal them at the end for
623 	 * now. */
624 	first_pd_entry_in_global_pt = gtt_total_entries(dev_priv->gtt);
625 
626 	ppgtt->base.pte_encode = dev_priv->gtt.base.pte_encode;
627 	ppgtt->num_pd_entries = GEN6_PPGTT_PD_ENTRIES;
628 	ppgtt->enable = gen6_ppgtt_enable;
629 	ppgtt->base.clear_range = gen6_ppgtt_clear_range;
630 	ppgtt->base.insert_entries = gen6_ppgtt_insert_entries;
631 	ppgtt->base.cleanup = gen6_ppgtt_cleanup;
632 	ppgtt->base.scratch = dev_priv->gtt.base.scratch;
633 	ppgtt->pt_pages = kcalloc(ppgtt->num_pd_entries, sizeof(struct page *),
634 				  GFP_KERNEL);
635 	if (!ppgtt->pt_pages)
636 		return -ENOMEM;
637 
638 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
639 		ppgtt->pt_pages[i] = alloc_page(GFP_KERNEL);
640 		if (!ppgtt->pt_pages[i])
641 			goto err_pt_alloc;
642 	}
643 
644 	ppgtt->pt_dma_addr = kcalloc(ppgtt->num_pd_entries, sizeof(dma_addr_t),
645 				     GFP_KERNEL);
646 	if (!ppgtt->pt_dma_addr)
647 		goto err_pt_alloc;
648 
649 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
650 		dma_addr_t pt_addr;
651 
652 		pt_addr = pci_map_page(dev->pdev, ppgtt->pt_pages[i], 0, 4096,
653 				       PCI_DMA_BIDIRECTIONAL);
654 
655 		if (pci_dma_mapping_error(dev->pdev, pt_addr)) {
656 			ret = -EIO;
657 			goto err_pd_pin;
658 
659 		}
660 		ppgtt->pt_dma_addr[i] = pt_addr;
661 	}
662 
663 	ppgtt->base.clear_range(&ppgtt->base, 0,
664 				ppgtt->num_pd_entries * I915_PPGTT_PT_ENTRIES, true);
665 
666 	ppgtt->pd_offset = first_pd_entry_in_global_pt * sizeof(gen6_gtt_pte_t);
667 
668 	return 0;
669 
670 err_pd_pin:
671 	if (ppgtt->pt_dma_addr) {
672 		for (i--; i >= 0; i--)
673 			pci_unmap_page(dev->pdev, ppgtt->pt_dma_addr[i],
674 				       4096, PCI_DMA_BIDIRECTIONAL);
675 	}
676 err_pt_alloc:
677 	kfree(ppgtt->pt_dma_addr);
678 	for (i = 0; i < ppgtt->num_pd_entries; i++) {
679 		if (ppgtt->pt_pages[i])
680 			__free_page(ppgtt->pt_pages[i]);
681 	}
682 	kfree(ppgtt->pt_pages);
683 
684 	return ret;
685 }
686 
687 static int i915_gem_init_aliasing_ppgtt(struct drm_device *dev)
688 {
689 	struct drm_i915_private *dev_priv = dev->dev_private;
690 	struct i915_hw_ppgtt *ppgtt;
691 	int ret;
692 
693 	ppgtt = kzalloc(sizeof(*ppgtt), GFP_KERNEL);
694 	if (!ppgtt)
695 		return -ENOMEM;
696 
697 	ppgtt->base.dev = dev;
698 
699 	if (INTEL_INFO(dev)->gen < 8)
700 		ret = gen6_ppgtt_init(ppgtt);
701 	else if (IS_GEN8(dev))
702 		ret = gen8_ppgtt_init(ppgtt, dev_priv->gtt.base.total);
703 	else
704 		BUG();
705 
706 	if (ret)
707 		kfree(ppgtt);
708 	else {
709 		dev_priv->mm.aliasing_ppgtt = ppgtt;
710 		drm_mm_init(&ppgtt->base.mm, ppgtt->base.start,
711 			    ppgtt->base.total);
712 	}
713 
714 	return ret;
715 }
716 
717 void i915_gem_cleanup_aliasing_ppgtt(struct drm_device *dev)
718 {
719 	struct drm_i915_private *dev_priv = dev->dev_private;
720 	struct i915_hw_ppgtt *ppgtt = dev_priv->mm.aliasing_ppgtt;
721 
722 	if (!ppgtt)
723 		return;
724 
725 	ppgtt->base.cleanup(&ppgtt->base);
726 	dev_priv->mm.aliasing_ppgtt = NULL;
727 }
728 
729 void i915_ppgtt_bind_object(struct i915_hw_ppgtt *ppgtt,
730 			    struct drm_i915_gem_object *obj,
731 			    enum i915_cache_level cache_level)
732 {
733 	ppgtt->base.insert_entries(&ppgtt->base, obj->pages,
734 				   i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT,
735 				   cache_level);
736 }
737 
738 void i915_ppgtt_unbind_object(struct i915_hw_ppgtt *ppgtt,
739 			      struct drm_i915_gem_object *obj)
740 {
741 	ppgtt->base.clear_range(&ppgtt->base,
742 				i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT,
743 				obj->base.size >> PAGE_SHIFT,
744 				true);
745 }
746 
747 extern int intel_iommu_gfx_mapped;
748 /* Certain Gen5 chipsets require require idling the GPU before
749  * unmapping anything from the GTT when VT-d is enabled.
750  */
751 static inline bool needs_idle_maps(struct drm_device *dev)
752 {
753 #ifdef CONFIG_INTEL_IOMMU
754 	/* Query intel_iommu to see if we need the workaround. Presumably that
755 	 * was loaded first.
756 	 */
757 	if (IS_GEN5(dev) && IS_MOBILE(dev) && intel_iommu_gfx_mapped)
758 		return true;
759 #endif
760 	return false;
761 }
762 
763 static bool do_idling(struct drm_i915_private *dev_priv)
764 {
765 	bool ret = dev_priv->mm.interruptible;
766 
767 	if (unlikely(dev_priv->gtt.do_idle_maps)) {
768 		dev_priv->mm.interruptible = false;
769 		if (i915_gpu_idle(dev_priv->dev)) {
770 			DRM_ERROR("Couldn't idle GPU\n");
771 			/* Wait a bit, in hopes it avoids the hang */
772 			udelay(10);
773 		}
774 	}
775 
776 	return ret;
777 }
778 
779 static void undo_idling(struct drm_i915_private *dev_priv, bool interruptible)
780 {
781 	if (unlikely(dev_priv->gtt.do_idle_maps))
782 		dev_priv->mm.interruptible = interruptible;
783 }
784 
785 void i915_check_and_clear_faults(struct drm_device *dev)
786 {
787 	struct drm_i915_private *dev_priv = dev->dev_private;
788 	struct intel_ring_buffer *ring;
789 	int i;
790 
791 	if (INTEL_INFO(dev)->gen < 6)
792 		return;
793 
794 	for_each_ring(ring, dev_priv, i) {
795 		u32 fault_reg;
796 		fault_reg = I915_READ(RING_FAULT_REG(ring));
797 		if (fault_reg & RING_FAULT_VALID) {
798 			DRM_DEBUG_DRIVER("Unexpected fault\n"
799 					 "\tAddr: 0x%08lx\\n"
800 					 "\tAddress space: %s\n"
801 					 "\tSource ID: %d\n"
802 					 "\tType: %d\n",
803 					 fault_reg & PAGE_MASK,
804 					 fault_reg & RING_FAULT_GTTSEL_MASK ? "GGTT" : "PPGTT",
805 					 RING_FAULT_SRCID(fault_reg),
806 					 RING_FAULT_FAULT_TYPE(fault_reg));
807 			I915_WRITE(RING_FAULT_REG(ring),
808 				   fault_reg & ~RING_FAULT_VALID);
809 		}
810 	}
811 	POSTING_READ(RING_FAULT_REG(&dev_priv->ring[RCS]));
812 }
813 
814 void i915_gem_suspend_gtt_mappings(struct drm_device *dev)
815 {
816 	struct drm_i915_private *dev_priv = dev->dev_private;
817 
818 	/* Don't bother messing with faults pre GEN6 as we have little
819 	 * documentation supporting that it's a good idea.
820 	 */
821 	if (INTEL_INFO(dev)->gen < 6)
822 		return;
823 
824 	i915_check_and_clear_faults(dev);
825 
826 	dev_priv->gtt.base.clear_range(&dev_priv->gtt.base,
827 				       dev_priv->gtt.base.start / PAGE_SIZE,
828 				       dev_priv->gtt.base.total / PAGE_SIZE,
829 				       false);
830 }
831 
832 void i915_gem_restore_gtt_mappings(struct drm_device *dev)
833 {
834 	struct drm_i915_private *dev_priv = dev->dev_private;
835 	struct drm_i915_gem_object *obj;
836 
837 	i915_check_and_clear_faults(dev);
838 
839 	/* First fill our portion of the GTT with scratch pages */
840 	dev_priv->gtt.base.clear_range(&dev_priv->gtt.base,
841 				       dev_priv->gtt.base.start / PAGE_SIZE,
842 				       dev_priv->gtt.base.total / PAGE_SIZE,
843 				       true);
844 
845 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
846 		i915_gem_clflush_object(obj, obj->pin_display);
847 		i915_gem_gtt_bind_object(obj, obj->cache_level);
848 	}
849 
850 	i915_gem_chipset_flush(dev);
851 }
852 
853 int i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj)
854 {
855 	if (obj->has_dma_mapping)
856 		return 0;
857 
858 	if (!dma_map_sg(&obj->base.dev->pdev->dev,
859 			obj->pages->sgl, obj->pages->nents,
860 			PCI_DMA_BIDIRECTIONAL))
861 		return -ENOSPC;
862 
863 	return 0;
864 }
865 
866 static inline void gen8_set_pte(void __iomem *addr, gen8_gtt_pte_t pte)
867 {
868 #ifdef writeq
869 	writeq(pte, addr);
870 #else
871 	iowrite32((u32)pte, addr);
872 	iowrite32(pte >> 32, addr + 4);
873 #endif
874 }
875 
876 static void gen8_ggtt_insert_entries(struct i915_address_space *vm,
877 				     struct sg_table *st,
878 				     unsigned int first_entry,
879 				     enum i915_cache_level level)
880 {
881 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
882 	gen8_gtt_pte_t __iomem *gtt_entries =
883 		(gen8_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry;
884 	int i = 0;
885 	struct sg_page_iter sg_iter;
886 	dma_addr_t addr;
887 
888 	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) {
889 		addr = sg_dma_address(sg_iter.sg) +
890 			(sg_iter.sg_pgoffset << PAGE_SHIFT);
891 		gen8_set_pte(&gtt_entries[i],
892 			     gen8_pte_encode(addr, level, true));
893 		i++;
894 	}
895 
896 	/*
897 	 * XXX: This serves as a posting read to make sure that the PTE has
898 	 * actually been updated. There is some concern that even though
899 	 * registers and PTEs are within the same BAR that they are potentially
900 	 * of NUMA access patterns. Therefore, even with the way we assume
901 	 * hardware should work, we must keep this posting read for paranoia.
902 	 */
903 	if (i != 0)
904 		WARN_ON(readq(&gtt_entries[i-1])
905 			!= gen8_pte_encode(addr, level, true));
906 
907 #if 0 /* TODO: Still needed on GEN8? */
908 	/* This next bit makes the above posting read even more important. We
909 	 * want to flush the TLBs only after we're certain all the PTE updates
910 	 * have finished.
911 	 */
912 	I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
913 	POSTING_READ(GFX_FLSH_CNTL_GEN6);
914 #endif
915 }
916 
917 /*
918  * Binds an object into the global gtt with the specified cache level. The object
919  * will be accessible to the GPU via commands whose operands reference offsets
920  * within the global GTT as well as accessible by the GPU through the GMADR
921  * mapped BAR (dev_priv->mm.gtt->gtt).
922  */
923 static void gen6_ggtt_insert_entries(struct i915_address_space *vm,
924 				     struct sg_table *st,
925 				     unsigned int first_entry,
926 				     enum i915_cache_level level)
927 {
928 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
929 	gen6_gtt_pte_t __iomem *gtt_entries =
930 		(gen6_gtt_pte_t __iomem *)dev_priv->gtt.gsm + first_entry;
931 	int i = 0;
932 	struct sg_page_iter sg_iter;
933 	dma_addr_t addr;
934 
935 	for_each_sg_page(st->sgl, &sg_iter, st->nents, 0) {
936 		addr = sg_page_iter_dma_address(&sg_iter);
937 		iowrite32(vm->pte_encode(addr, level, true), &gtt_entries[i]);
938 		i++;
939 	}
940 
941 	/* XXX: This serves as a posting read to make sure that the PTE has
942 	 * actually been updated. There is some concern that even though
943 	 * registers and PTEs are within the same BAR that they are potentially
944 	 * of NUMA access patterns. Therefore, even with the way we assume
945 	 * hardware should work, we must keep this posting read for paranoia.
946 	 */
947 	if (i != 0)
948 		WARN_ON(readl(&gtt_entries[i-1]) !=
949 			vm->pte_encode(addr, level, true));
950 
951 	/* This next bit makes the above posting read even more important. We
952 	 * want to flush the TLBs only after we're certain all the PTE updates
953 	 * have finished.
954 	 */
955 	I915_WRITE(GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
956 	POSTING_READ(GFX_FLSH_CNTL_GEN6);
957 }
958 
959 static void gen8_ggtt_clear_range(struct i915_address_space *vm,
960 				  unsigned int first_entry,
961 				  unsigned int num_entries,
962 				  bool use_scratch)
963 {
964 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
965 	gen8_gtt_pte_t scratch_pte, __iomem *gtt_base =
966 		(gen8_gtt_pte_t __iomem *) dev_priv->gtt.gsm + first_entry;
967 	const int max_entries = gtt_total_entries(dev_priv->gtt) - first_entry;
968 	int i;
969 
970 	if (WARN(num_entries > max_entries,
971 		 "First entry = %d; Num entries = %d (max=%d)\n",
972 		 first_entry, num_entries, max_entries))
973 		num_entries = max_entries;
974 
975 	scratch_pte = gen8_pte_encode(vm->scratch.addr,
976 				      I915_CACHE_LLC,
977 				      use_scratch);
978 	for (i = 0; i < num_entries; i++)
979 		gen8_set_pte(&gtt_base[i], scratch_pte);
980 	readl(gtt_base);
981 }
982 
983 static void gen6_ggtt_clear_range(struct i915_address_space *vm,
984 				  unsigned int first_entry,
985 				  unsigned int num_entries,
986 				  bool use_scratch)
987 {
988 	struct drm_i915_private *dev_priv = vm->dev->dev_private;
989 	gen6_gtt_pte_t scratch_pte, __iomem *gtt_base =
990 		(gen6_gtt_pte_t __iomem *) dev_priv->gtt.gsm + first_entry;
991 	const int max_entries = gtt_total_entries(dev_priv->gtt) - first_entry;
992 	int i;
993 
994 	if (WARN(num_entries > max_entries,
995 		 "First entry = %d; Num entries = %d (max=%d)\n",
996 		 first_entry, num_entries, max_entries))
997 		num_entries = max_entries;
998 
999 	scratch_pte = vm->pte_encode(vm->scratch.addr, I915_CACHE_LLC, use_scratch);
1000 
1001 	for (i = 0; i < num_entries; i++)
1002 		iowrite32(scratch_pte, &gtt_base[i]);
1003 	readl(gtt_base);
1004 }
1005 
1006 static void i915_ggtt_insert_entries(struct i915_address_space *vm,
1007 				     struct sg_table *st,
1008 				     unsigned int pg_start,
1009 				     enum i915_cache_level cache_level)
1010 {
1011 	unsigned int flags = (cache_level == I915_CACHE_NONE) ?
1012 		AGP_USER_MEMORY : AGP_USER_CACHED_MEMORY;
1013 
1014 	intel_gtt_insert_sg_entries(st, pg_start, flags);
1015 
1016 }
1017 
1018 static void i915_ggtt_clear_range(struct i915_address_space *vm,
1019 				  unsigned int first_entry,
1020 				  unsigned int num_entries,
1021 				  bool unused)
1022 {
1023 	intel_gtt_clear_range(first_entry, num_entries);
1024 }
1025 
1026 
1027 void i915_gem_gtt_bind_object(struct drm_i915_gem_object *obj,
1028 			      enum i915_cache_level cache_level)
1029 {
1030 	struct drm_device *dev = obj->base.dev;
1031 	struct drm_i915_private *dev_priv = dev->dev_private;
1032 	const unsigned long entry = i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT;
1033 
1034 	dev_priv->gtt.base.insert_entries(&dev_priv->gtt.base, obj->pages,
1035 					  entry,
1036 					  cache_level);
1037 
1038 	obj->has_global_gtt_mapping = 1;
1039 }
1040 
1041 void i915_gem_gtt_unbind_object(struct drm_i915_gem_object *obj)
1042 {
1043 	struct drm_device *dev = obj->base.dev;
1044 	struct drm_i915_private *dev_priv = dev->dev_private;
1045 	const unsigned long entry = i915_gem_obj_ggtt_offset(obj) >> PAGE_SHIFT;
1046 
1047 	dev_priv->gtt.base.clear_range(&dev_priv->gtt.base,
1048 				       entry,
1049 				       obj->base.size >> PAGE_SHIFT,
1050 				       true);
1051 
1052 	obj->has_global_gtt_mapping = 0;
1053 }
1054 
1055 void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj)
1056 {
1057 	struct drm_device *dev = obj->base.dev;
1058 	struct drm_i915_private *dev_priv = dev->dev_private;
1059 	bool interruptible;
1060 
1061 	interruptible = do_idling(dev_priv);
1062 
1063 	if (!obj->has_dma_mapping)
1064 		dma_unmap_sg(&dev->pdev->dev,
1065 			     obj->pages->sgl, obj->pages->nents,
1066 			     PCI_DMA_BIDIRECTIONAL);
1067 
1068 	undo_idling(dev_priv, interruptible);
1069 }
1070 
1071 static void i915_gtt_color_adjust(struct drm_mm_node *node,
1072 				  unsigned long color,
1073 				  unsigned long *start,
1074 				  unsigned long *end)
1075 {
1076 	if (node->color != color)
1077 		*start += 4096;
1078 
1079 	if (!list_empty(&node->node_list)) {
1080 		node = list_entry(node->node_list.next,
1081 				  struct drm_mm_node,
1082 				  node_list);
1083 		if (node->allocated && node->color != color)
1084 			*end -= 4096;
1085 	}
1086 }
1087 
1088 void i915_gem_setup_global_gtt(struct drm_device *dev,
1089 			       unsigned long start,
1090 			       unsigned long mappable_end,
1091 			       unsigned long end)
1092 {
1093 	/* Let GEM Manage all of the aperture.
1094 	 *
1095 	 * However, leave one page at the end still bound to the scratch page.
1096 	 * There are a number of places where the hardware apparently prefetches
1097 	 * past the end of the object, and we've seen multiple hangs with the
1098 	 * GPU head pointer stuck in a batchbuffer bound at the last page of the
1099 	 * aperture.  One page should be enough to keep any prefetching inside
1100 	 * of the aperture.
1101 	 */
1102 	struct drm_i915_private *dev_priv = dev->dev_private;
1103 	struct i915_address_space *ggtt_vm = &dev_priv->gtt.base;
1104 	struct drm_mm_node *entry;
1105 	struct drm_i915_gem_object *obj;
1106 	unsigned long hole_start, hole_end;
1107 
1108 	BUG_ON(mappable_end > end);
1109 
1110 	/* Subtract the guard page ... */
1111 	drm_mm_init(&ggtt_vm->mm, start, end - start - PAGE_SIZE);
1112 	if (!HAS_LLC(dev))
1113 		dev_priv->gtt.base.mm.color_adjust = i915_gtt_color_adjust;
1114 
1115 	/* Mark any preallocated objects as occupied */
1116 	list_for_each_entry(obj, &dev_priv->mm.bound_list, global_list) {
1117 		struct i915_vma *vma = i915_gem_obj_to_vma(obj, ggtt_vm);
1118 		int ret;
1119 		DRM_DEBUG_KMS("reserving preallocated space: %lx + %zx\n",
1120 			      i915_gem_obj_ggtt_offset(obj), obj->base.size);
1121 
1122 		WARN_ON(i915_gem_obj_ggtt_bound(obj));
1123 		ret = drm_mm_reserve_node(&ggtt_vm->mm, &vma->node);
1124 		if (ret)
1125 			DRM_DEBUG_KMS("Reservation failed\n");
1126 		obj->has_global_gtt_mapping = 1;
1127 		list_add(&vma->vma_link, &obj->vma_list);
1128 	}
1129 
1130 	dev_priv->gtt.base.start = start;
1131 	dev_priv->gtt.base.total = end - start;
1132 
1133 	/* Clear any non-preallocated blocks */
1134 	drm_mm_for_each_hole(entry, &ggtt_vm->mm, hole_start, hole_end) {
1135 		const unsigned long count = (hole_end - hole_start) / PAGE_SIZE;
1136 		DRM_DEBUG_KMS("clearing unused GTT space: [%lx, %lx]\n",
1137 			      hole_start, hole_end);
1138 		ggtt_vm->clear_range(ggtt_vm, hole_start / PAGE_SIZE, count, true);
1139 	}
1140 
1141 	/* And finally clear the reserved guard page */
1142 	ggtt_vm->clear_range(ggtt_vm, end / PAGE_SIZE - 1, 1, true);
1143 }
1144 
1145 static bool
1146 intel_enable_ppgtt(struct drm_device *dev)
1147 {
1148 	if (i915_enable_ppgtt >= 0)
1149 		return i915_enable_ppgtt;
1150 
1151 #ifdef CONFIG_INTEL_IOMMU
1152 	/* Disable ppgtt on SNB if VT-d is on. */
1153 	if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped)
1154 		return false;
1155 #endif
1156 
1157 	return true;
1158 }
1159 
1160 void i915_gem_init_global_gtt(struct drm_device *dev)
1161 {
1162 	struct drm_i915_private *dev_priv = dev->dev_private;
1163 	unsigned long gtt_size, mappable_size;
1164 
1165 	gtt_size = dev_priv->gtt.base.total;
1166 	mappable_size = dev_priv->gtt.mappable_end;
1167 
1168 	if (intel_enable_ppgtt(dev) && HAS_ALIASING_PPGTT(dev)) {
1169 		int ret;
1170 
1171 		if (INTEL_INFO(dev)->gen <= 7) {
1172 			/* PPGTT pdes are stolen from global gtt ptes, so shrink the
1173 			 * aperture accordingly when using aliasing ppgtt. */
1174 			gtt_size -= GEN6_PPGTT_PD_ENTRIES * PAGE_SIZE;
1175 		}
1176 
1177 		i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
1178 
1179 		ret = i915_gem_init_aliasing_ppgtt(dev);
1180 		if (!ret)
1181 			return;
1182 
1183 		DRM_ERROR("Aliased PPGTT setup failed %d\n", ret);
1184 		drm_mm_takedown(&dev_priv->gtt.base.mm);
1185 		if (INTEL_INFO(dev)->gen < 8)
1186 			gtt_size += GEN6_PPGTT_PD_ENTRIES*PAGE_SIZE;
1187 	}
1188 	i915_gem_setup_global_gtt(dev, 0, mappable_size, gtt_size);
1189 }
1190 
1191 static int setup_scratch_page(struct drm_device *dev)
1192 {
1193 	struct drm_i915_private *dev_priv = dev->dev_private;
1194 	struct page *page;
1195 	dma_addr_t dma_addr;
1196 
1197 	page = alloc_page(GFP_KERNEL | GFP_DMA32 | __GFP_ZERO);
1198 	if (page == NULL)
1199 		return -ENOMEM;
1200 	get_page(page);
1201 	set_pages_uc(page, 1);
1202 
1203 #ifdef CONFIG_INTEL_IOMMU
1204 	dma_addr = pci_map_page(dev->pdev, page, 0, PAGE_SIZE,
1205 				PCI_DMA_BIDIRECTIONAL);
1206 	if (pci_dma_mapping_error(dev->pdev, dma_addr))
1207 		return -EINVAL;
1208 #else
1209 	dma_addr = page_to_phys(page);
1210 #endif
1211 	dev_priv->gtt.base.scratch.page = page;
1212 	dev_priv->gtt.base.scratch.addr = dma_addr;
1213 
1214 	return 0;
1215 }
1216 
1217 static void teardown_scratch_page(struct drm_device *dev)
1218 {
1219 	struct drm_i915_private *dev_priv = dev->dev_private;
1220 	struct page *page = dev_priv->gtt.base.scratch.page;
1221 
1222 	set_pages_wb(page, 1);
1223 	pci_unmap_page(dev->pdev, dev_priv->gtt.base.scratch.addr,
1224 		       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
1225 	put_page(page);
1226 	__free_page(page);
1227 }
1228 
1229 static inline unsigned int gen6_get_total_gtt_size(u16 snb_gmch_ctl)
1230 {
1231 	snb_gmch_ctl >>= SNB_GMCH_GGMS_SHIFT;
1232 	snb_gmch_ctl &= SNB_GMCH_GGMS_MASK;
1233 	return snb_gmch_ctl << 20;
1234 }
1235 
1236 static inline unsigned int gen8_get_total_gtt_size(u16 bdw_gmch_ctl)
1237 {
1238 	bdw_gmch_ctl >>= BDW_GMCH_GGMS_SHIFT;
1239 	bdw_gmch_ctl &= BDW_GMCH_GGMS_MASK;
1240 	if (bdw_gmch_ctl)
1241 		bdw_gmch_ctl = 1 << bdw_gmch_ctl;
1242 	return bdw_gmch_ctl << 20;
1243 }
1244 
1245 static inline size_t gen6_get_stolen_size(u16 snb_gmch_ctl)
1246 {
1247 	snb_gmch_ctl >>= SNB_GMCH_GMS_SHIFT;
1248 	snb_gmch_ctl &= SNB_GMCH_GMS_MASK;
1249 	return snb_gmch_ctl << 25; /* 32 MB units */
1250 }
1251 
1252 static inline size_t gen8_get_stolen_size(u16 bdw_gmch_ctl)
1253 {
1254 	bdw_gmch_ctl >>= BDW_GMCH_GMS_SHIFT;
1255 	bdw_gmch_ctl &= BDW_GMCH_GMS_MASK;
1256 	return bdw_gmch_ctl << 25; /* 32 MB units */
1257 }
1258 
1259 static int ggtt_probe_common(struct drm_device *dev,
1260 			     size_t gtt_size)
1261 {
1262 	struct drm_i915_private *dev_priv = dev->dev_private;
1263 	phys_addr_t gtt_bus_addr;
1264 	int ret;
1265 
1266 	/* For Modern GENs the PTEs and register space are split in the BAR */
1267 	gtt_bus_addr = pci_resource_start(dev->pdev, 0) +
1268 		(pci_resource_len(dev->pdev, 0) / 2);
1269 
1270 	dev_priv->gtt.gsm = ioremap_wc(gtt_bus_addr, gtt_size);
1271 	if (!dev_priv->gtt.gsm) {
1272 		DRM_ERROR("Failed to map the gtt page table\n");
1273 		return -ENOMEM;
1274 	}
1275 
1276 	ret = setup_scratch_page(dev);
1277 	if (ret) {
1278 		DRM_ERROR("Scratch setup failed\n");
1279 		/* iounmap will also get called at remove, but meh */
1280 		iounmap(dev_priv->gtt.gsm);
1281 	}
1282 
1283 	return ret;
1284 }
1285 
1286 /* The GGTT and PPGTT need a private PPAT setup in order to handle cacheability
1287  * bits. When using advanced contexts each context stores its own PAT, but
1288  * writing this data shouldn't be harmful even in those cases. */
1289 static void gen8_setup_private_ppat(struct drm_i915_private *dev_priv)
1290 {
1291 #define GEN8_PPAT_UC		(0<<0)
1292 #define GEN8_PPAT_WC		(1<<0)
1293 #define GEN8_PPAT_WT		(2<<0)
1294 #define GEN8_PPAT_WB		(3<<0)
1295 #define GEN8_PPAT_ELLC_OVERRIDE	(0<<2)
1296 /* FIXME(BDW): Bspec is completely confused about cache control bits. */
1297 #define GEN8_PPAT_LLC		(1<<2)
1298 #define GEN8_PPAT_LLCELLC	(2<<2)
1299 #define GEN8_PPAT_LLCeLLC	(3<<2)
1300 #define GEN8_PPAT_AGE(x)	(x<<4)
1301 #define GEN8_PPAT(i, x) ((uint64_t) (x) << ((i) * 8))
1302 	uint64_t pat;
1303 
1304 	pat = GEN8_PPAT(0, GEN8_PPAT_WB | GEN8_PPAT_LLC)     | /* for normal objects, no eLLC */
1305 	      GEN8_PPAT(1, GEN8_PPAT_WC | GEN8_PPAT_LLCELLC) | /* for something pointing to ptes? */
1306 	      GEN8_PPAT(2, GEN8_PPAT_WT | GEN8_PPAT_LLCELLC) | /* for scanout with eLLC */
1307 	      GEN8_PPAT(3, GEN8_PPAT_UC)                     | /* Uncached objects, mostly for scanout */
1308 	      GEN8_PPAT(4, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(0)) |
1309 	      GEN8_PPAT(5, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(1)) |
1310 	      GEN8_PPAT(6, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(2)) |
1311 	      GEN8_PPAT(7, GEN8_PPAT_WB | GEN8_PPAT_LLCELLC | GEN8_PPAT_AGE(3));
1312 
1313 	/* XXX: spec defines this as 2 distinct registers. It's unclear if a 64b
1314 	 * write would work. */
1315 	I915_WRITE(GEN8_PRIVATE_PAT, pat);
1316 	I915_WRITE(GEN8_PRIVATE_PAT + 4, pat >> 32);
1317 }
1318 
1319 static int gen8_gmch_probe(struct drm_device *dev,
1320 			   size_t *gtt_total,
1321 			   size_t *stolen,
1322 			   phys_addr_t *mappable_base,
1323 			   unsigned long *mappable_end)
1324 {
1325 	struct drm_i915_private *dev_priv = dev->dev_private;
1326 	unsigned int gtt_size;
1327 	u16 snb_gmch_ctl;
1328 	int ret;
1329 
1330 	/* TODO: We're not aware of mappable constraints on gen8 yet */
1331 	*mappable_base = pci_resource_start(dev->pdev, 2);
1332 	*mappable_end = pci_resource_len(dev->pdev, 2);
1333 
1334 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(39)))
1335 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(39));
1336 
1337 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
1338 
1339 	*stolen = gen8_get_stolen_size(snb_gmch_ctl);
1340 
1341 	gtt_size = gen8_get_total_gtt_size(snb_gmch_ctl);
1342 	*gtt_total = (gtt_size / sizeof(gen8_gtt_pte_t)) << PAGE_SHIFT;
1343 
1344 	gen8_setup_private_ppat(dev_priv);
1345 
1346 	ret = ggtt_probe_common(dev, gtt_size);
1347 
1348 	dev_priv->gtt.base.clear_range = gen8_ggtt_clear_range;
1349 	dev_priv->gtt.base.insert_entries = gen8_ggtt_insert_entries;
1350 
1351 	return ret;
1352 }
1353 
1354 static int gen6_gmch_probe(struct drm_device *dev,
1355 			   size_t *gtt_total,
1356 			   size_t *stolen,
1357 			   phys_addr_t *mappable_base,
1358 			   unsigned long *mappable_end)
1359 {
1360 	struct drm_i915_private *dev_priv = dev->dev_private;
1361 	unsigned int gtt_size;
1362 	u16 snb_gmch_ctl;
1363 	int ret;
1364 
1365 	*mappable_base = pci_resource_start(dev->pdev, 2);
1366 	*mappable_end = pci_resource_len(dev->pdev, 2);
1367 
1368 	/* 64/512MB is the current min/max we actually know of, but this is just
1369 	 * a coarse sanity check.
1370 	 */
1371 	if ((*mappable_end < (64<<20) || (*mappable_end > (512<<20)))) {
1372 		DRM_ERROR("Unknown GMADR size (%lx)\n",
1373 			  dev_priv->gtt.mappable_end);
1374 		return -ENXIO;
1375 	}
1376 
1377 	if (!pci_set_dma_mask(dev->pdev, DMA_BIT_MASK(40)))
1378 		pci_set_consistent_dma_mask(dev->pdev, DMA_BIT_MASK(40));
1379 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
1380 
1381 	*stolen = gen6_get_stolen_size(snb_gmch_ctl);
1382 
1383 	gtt_size = gen6_get_total_gtt_size(snb_gmch_ctl);
1384 	*gtt_total = (gtt_size / sizeof(gen6_gtt_pte_t)) << PAGE_SHIFT;
1385 
1386 	ret = ggtt_probe_common(dev, gtt_size);
1387 
1388 	dev_priv->gtt.base.clear_range = gen6_ggtt_clear_range;
1389 	dev_priv->gtt.base.insert_entries = gen6_ggtt_insert_entries;
1390 
1391 	return ret;
1392 }
1393 
1394 static void gen6_gmch_remove(struct i915_address_space *vm)
1395 {
1396 
1397 	struct i915_gtt *gtt = container_of(vm, struct i915_gtt, base);
1398 	iounmap(gtt->gsm);
1399 	teardown_scratch_page(vm->dev);
1400 }
1401 
1402 static int i915_gmch_probe(struct drm_device *dev,
1403 			   size_t *gtt_total,
1404 			   size_t *stolen,
1405 			   phys_addr_t *mappable_base,
1406 			   unsigned long *mappable_end)
1407 {
1408 	struct drm_i915_private *dev_priv = dev->dev_private;
1409 	int ret;
1410 
1411 	ret = intel_gmch_probe(dev_priv->bridge_dev, dev_priv->dev->pdev, NULL);
1412 	if (!ret) {
1413 		DRM_ERROR("failed to set up gmch\n");
1414 		return -EIO;
1415 	}
1416 
1417 	intel_gtt_get(gtt_total, stolen, mappable_base, mappable_end);
1418 
1419 	dev_priv->gtt.do_idle_maps = needs_idle_maps(dev_priv->dev);
1420 	dev_priv->gtt.base.clear_range = i915_ggtt_clear_range;
1421 	dev_priv->gtt.base.insert_entries = i915_ggtt_insert_entries;
1422 
1423 	return 0;
1424 }
1425 
1426 static void i915_gmch_remove(struct i915_address_space *vm)
1427 {
1428 	intel_gmch_remove();
1429 }
1430 
1431 int i915_gem_gtt_init(struct drm_device *dev)
1432 {
1433 	struct drm_i915_private *dev_priv = dev->dev_private;
1434 	struct i915_gtt *gtt = &dev_priv->gtt;
1435 	int ret;
1436 
1437 	if (INTEL_INFO(dev)->gen <= 5) {
1438 		gtt->gtt_probe = i915_gmch_probe;
1439 		gtt->base.cleanup = i915_gmch_remove;
1440 	} else if (INTEL_INFO(dev)->gen < 8) {
1441 		gtt->gtt_probe = gen6_gmch_probe;
1442 		gtt->base.cleanup = gen6_gmch_remove;
1443 		if (IS_HASWELL(dev) && dev_priv->ellc_size)
1444 			gtt->base.pte_encode = iris_pte_encode;
1445 		else if (IS_HASWELL(dev))
1446 			gtt->base.pte_encode = hsw_pte_encode;
1447 		else if (IS_VALLEYVIEW(dev))
1448 			gtt->base.pte_encode = byt_pte_encode;
1449 		else if (INTEL_INFO(dev)->gen >= 7)
1450 			gtt->base.pte_encode = ivb_pte_encode;
1451 		else
1452 			gtt->base.pte_encode = snb_pte_encode;
1453 	} else {
1454 		dev_priv->gtt.gtt_probe = gen8_gmch_probe;
1455 		dev_priv->gtt.base.cleanup = gen6_gmch_remove;
1456 	}
1457 
1458 	ret = gtt->gtt_probe(dev, &gtt->base.total, &gtt->stolen_size,
1459 			     &gtt->mappable_base, &gtt->mappable_end);
1460 	if (ret)
1461 		return ret;
1462 
1463 	gtt->base.dev = dev;
1464 
1465 	/* GMADR is the PCI mmio aperture into the global GTT. */
1466 	DRM_INFO("Memory usable by graphics device = %zdM\n",
1467 		 gtt->base.total >> 20);
1468 	DRM_DEBUG_DRIVER("GMADR size = %ldM\n", gtt->mappable_end >> 20);
1469 	DRM_DEBUG_DRIVER("GTT stolen size = %zdM\n", gtt->stolen_size >> 20);
1470 
1471 	return 0;
1472 }
1473