xref: /linux/drivers/gpu/drm/i915/gt/gen8_ppgtt.c (revision 6e7fd890f1d6ac83805409e9c346240de2705584)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 
6 #include <linux/log2.h>
7 
8 #include "gem/i915_gem_internal.h"
9 #include "gem/i915_gem_lmem.h"
10 
11 #include "gen8_ppgtt.h"
12 #include "i915_scatterlist.h"
13 #include "i915_trace.h"
14 #include "i915_pvinfo.h"
15 #include "i915_vgpu.h"
16 #include "intel_gt.h"
17 #include "intel_gtt.h"
18 
19 static u64 gen8_pde_encode(const dma_addr_t addr,
20 			   const enum i915_cache_level level)
21 {
22 	u64 pde = addr | GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
23 
24 	if (level != I915_CACHE_NONE)
25 		pde |= PPAT_CACHED_PDE;
26 	else
27 		pde |= PPAT_UNCACHED;
28 
29 	return pde;
30 }
31 
32 static u64 gen8_pte_encode(dma_addr_t addr,
33 			   unsigned int pat_index,
34 			   u32 flags)
35 {
36 	gen8_pte_t pte = addr | GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
37 
38 	if (unlikely(flags & PTE_READ_ONLY))
39 		pte &= ~GEN8_PAGE_RW;
40 
41 	/*
42 	 * For pre-gen12 platforms pat_index is the same as enum
43 	 * i915_cache_level, so the switch-case here is still valid.
44 	 * See translation table defined by LEGACY_CACHELEVEL.
45 	 */
46 	switch (pat_index) {
47 	case I915_CACHE_NONE:
48 		pte |= PPAT_UNCACHED;
49 		break;
50 	case I915_CACHE_WT:
51 		pte |= PPAT_DISPLAY_ELLC;
52 		break;
53 	default:
54 		pte |= PPAT_CACHED;
55 		break;
56 	}
57 
58 	return pte;
59 }
60 
61 static u64 gen12_pte_encode(dma_addr_t addr,
62 			    unsigned int pat_index,
63 			    u32 flags)
64 {
65 	gen8_pte_t pte = addr | GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
66 
67 	if (unlikely(flags & PTE_READ_ONLY))
68 		pte &= ~GEN8_PAGE_RW;
69 
70 	if (flags & PTE_LM)
71 		pte |= GEN12_PPGTT_PTE_LM;
72 
73 	if (pat_index & BIT(0))
74 		pte |= GEN12_PPGTT_PTE_PAT0;
75 
76 	if (pat_index & BIT(1))
77 		pte |= GEN12_PPGTT_PTE_PAT1;
78 
79 	if (pat_index & BIT(2))
80 		pte |= GEN12_PPGTT_PTE_PAT2;
81 
82 	if (pat_index & BIT(3))
83 		pte |= MTL_PPGTT_PTE_PAT3;
84 
85 	return pte;
86 }
87 
88 static void gen8_ppgtt_notify_vgt(struct i915_ppgtt *ppgtt, bool create)
89 {
90 	struct drm_i915_private *i915 = ppgtt->vm.i915;
91 	struct intel_uncore *uncore = ppgtt->vm.gt->uncore;
92 	enum vgt_g2v_type msg;
93 	int i;
94 
95 	if (create)
96 		atomic_inc(px_used(ppgtt->pd)); /* never remove */
97 	else
98 		atomic_dec(px_used(ppgtt->pd));
99 
100 	mutex_lock(&i915->vgpu.lock);
101 
102 	if (i915_vm_is_4lvl(&ppgtt->vm)) {
103 		const u64 daddr = px_dma(ppgtt->pd);
104 
105 		intel_uncore_write(uncore,
106 				   vgtif_reg(pdp[0].lo), lower_32_bits(daddr));
107 		intel_uncore_write(uncore,
108 				   vgtif_reg(pdp[0].hi), upper_32_bits(daddr));
109 
110 		msg = create ?
111 			VGT_G2V_PPGTT_L4_PAGE_TABLE_CREATE :
112 			VGT_G2V_PPGTT_L4_PAGE_TABLE_DESTROY;
113 	} else {
114 		for (i = 0; i < GEN8_3LVL_PDPES; i++) {
115 			const u64 daddr = i915_page_dir_dma_addr(ppgtt, i);
116 
117 			intel_uncore_write(uncore,
118 					   vgtif_reg(pdp[i].lo),
119 					   lower_32_bits(daddr));
120 			intel_uncore_write(uncore,
121 					   vgtif_reg(pdp[i].hi),
122 					   upper_32_bits(daddr));
123 		}
124 
125 		msg = create ?
126 			VGT_G2V_PPGTT_L3_PAGE_TABLE_CREATE :
127 			VGT_G2V_PPGTT_L3_PAGE_TABLE_DESTROY;
128 	}
129 
130 	/* g2v_notify atomically (via hv trap) consumes the message packet. */
131 	intel_uncore_write(uncore, vgtif_reg(g2v_notify), msg);
132 
133 	mutex_unlock(&i915->vgpu.lock);
134 }
135 
136 /* Index shifts into the pagetable are offset by GEN8_PTE_SHIFT [12] */
137 #define GEN8_PAGE_SIZE (SZ_4K) /* page and page-directory sizes are the same */
138 #define GEN8_PTE_SHIFT (ilog2(GEN8_PAGE_SIZE))
139 #define GEN8_PDES (GEN8_PAGE_SIZE / sizeof(u64))
140 #define gen8_pd_shift(lvl) ((lvl) * ilog2(GEN8_PDES))
141 #define gen8_pd_index(i, lvl) i915_pde_index((i), gen8_pd_shift(lvl))
142 #define __gen8_pte_shift(lvl) (GEN8_PTE_SHIFT + gen8_pd_shift(lvl))
143 #define __gen8_pte_index(a, lvl) i915_pde_index((a), __gen8_pte_shift(lvl))
144 
145 #define as_pd(x) container_of((x), typeof(struct i915_page_directory), pt)
146 
147 static unsigned int
148 gen8_pd_range(u64 start, u64 end, int lvl, unsigned int *idx)
149 {
150 	const int shift = gen8_pd_shift(lvl);
151 	const u64 mask = ~0ull << gen8_pd_shift(lvl + 1);
152 
153 	GEM_BUG_ON(start >= end);
154 	end += ~mask >> gen8_pd_shift(1);
155 
156 	*idx = i915_pde_index(start, shift);
157 	if ((start ^ end) & mask)
158 		return GEN8_PDES - *idx;
159 	else
160 		return i915_pde_index(end, shift) - *idx;
161 }
162 
163 static bool gen8_pd_contains(u64 start, u64 end, int lvl)
164 {
165 	const u64 mask = ~0ull << gen8_pd_shift(lvl + 1);
166 
167 	GEM_BUG_ON(start >= end);
168 	return (start ^ end) & mask && (start & ~mask) == 0;
169 }
170 
171 static unsigned int gen8_pt_count(u64 start, u64 end)
172 {
173 	GEM_BUG_ON(start >= end);
174 	if ((start ^ end) >> gen8_pd_shift(1))
175 		return GEN8_PDES - (start & (GEN8_PDES - 1));
176 	else
177 		return end - start;
178 }
179 
180 static unsigned int gen8_pd_top_count(const struct i915_address_space *vm)
181 {
182 	unsigned int shift = __gen8_pte_shift(vm->top);
183 
184 	return (vm->total + (1ull << shift) - 1) >> shift;
185 }
186 
187 static struct i915_page_directory *
188 gen8_pdp_for_page_index(struct i915_address_space * const vm, const u64 idx)
189 {
190 	struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm);
191 
192 	if (vm->top == 2)
193 		return ppgtt->pd;
194 	else
195 		return i915_pd_entry(ppgtt->pd, gen8_pd_index(idx, vm->top));
196 }
197 
198 static struct i915_page_directory *
199 gen8_pdp_for_page_address(struct i915_address_space * const vm, const u64 addr)
200 {
201 	return gen8_pdp_for_page_index(vm, addr >> GEN8_PTE_SHIFT);
202 }
203 
204 static void __gen8_ppgtt_cleanup(struct i915_address_space *vm,
205 				 struct i915_page_directory *pd,
206 				 int count, int lvl)
207 {
208 	if (lvl) {
209 		void **pde = pd->entry;
210 
211 		do {
212 			if (!*pde)
213 				continue;
214 
215 			__gen8_ppgtt_cleanup(vm, *pde, GEN8_PDES, lvl - 1);
216 		} while (pde++, --count);
217 	}
218 
219 	free_px(vm, &pd->pt, lvl);
220 }
221 
222 static void gen8_ppgtt_cleanup(struct i915_address_space *vm)
223 {
224 	struct i915_ppgtt *ppgtt = i915_vm_to_ppgtt(vm);
225 
226 	if (vm->rsvd.obj)
227 		i915_gem_object_put(vm->rsvd.obj);
228 
229 	if (intel_vgpu_active(vm->i915))
230 		gen8_ppgtt_notify_vgt(ppgtt, false);
231 
232 	if (ppgtt->pd)
233 		__gen8_ppgtt_cleanup(vm, ppgtt->pd,
234 				     gen8_pd_top_count(vm), vm->top);
235 
236 	free_scratch(vm);
237 }
238 
239 static u64 __gen8_ppgtt_clear(struct i915_address_space * const vm,
240 			      struct i915_page_directory * const pd,
241 			      u64 start, const u64 end, int lvl)
242 {
243 	const struct drm_i915_gem_object * const scratch = vm->scratch[lvl];
244 	unsigned int idx, len;
245 
246 	GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT);
247 
248 	len = gen8_pd_range(start, end, lvl--, &idx);
249 	GTT_TRACE("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n",
250 		  __func__, vm, lvl + 1, start, end,
251 		  idx, len, atomic_read(px_used(pd)));
252 	GEM_BUG_ON(!len || len >= atomic_read(px_used(pd)));
253 
254 	do {
255 		struct i915_page_table *pt = pd->entry[idx];
256 
257 		if (atomic_fetch_inc(&pt->used) >> gen8_pd_shift(1) &&
258 		    gen8_pd_contains(start, end, lvl)) {
259 			GTT_TRACE("%s(%p):{ lvl:%d, idx:%d, start:%llx, end:%llx } removing pd\n",
260 				  __func__, vm, lvl + 1, idx, start, end);
261 			clear_pd_entry(pd, idx, scratch);
262 			__gen8_ppgtt_cleanup(vm, as_pd(pt), I915_PDES, lvl);
263 			start += (u64)I915_PDES << gen8_pd_shift(lvl);
264 			continue;
265 		}
266 
267 		if (lvl) {
268 			start = __gen8_ppgtt_clear(vm, as_pd(pt),
269 						   start, end, lvl);
270 		} else {
271 			unsigned int count;
272 			unsigned int pte = gen8_pd_index(start, 0);
273 			unsigned int num_ptes;
274 			u64 *vaddr;
275 
276 			count = gen8_pt_count(start, end);
277 			GTT_TRACE("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } removing pte\n",
278 				  __func__, vm, lvl, start, end,
279 				  gen8_pd_index(start, 0), count,
280 				  atomic_read(&pt->used));
281 			GEM_BUG_ON(!count || count >= atomic_read(&pt->used));
282 
283 			num_ptes = count;
284 			if (pt->is_compact) {
285 				GEM_BUG_ON(num_ptes % 16);
286 				GEM_BUG_ON(pte % 16);
287 				num_ptes /= 16;
288 				pte /= 16;
289 			}
290 
291 			vaddr = px_vaddr(pt);
292 			memset64(vaddr + pte,
293 				 vm->scratch[0]->encode,
294 				 num_ptes);
295 
296 			atomic_sub(count, &pt->used);
297 			start += count;
298 		}
299 
300 		if (release_pd_entry(pd, idx, pt, scratch))
301 			free_px(vm, pt, lvl);
302 	} while (idx++, --len);
303 
304 	return start;
305 }
306 
307 static void gen8_ppgtt_clear(struct i915_address_space *vm,
308 			     u64 start, u64 length)
309 {
310 	GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT)));
311 	GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT)));
312 	GEM_BUG_ON(range_overflows(start, length, vm->total));
313 
314 	start >>= GEN8_PTE_SHIFT;
315 	length >>= GEN8_PTE_SHIFT;
316 	GEM_BUG_ON(length == 0);
317 
318 	__gen8_ppgtt_clear(vm, i915_vm_to_ppgtt(vm)->pd,
319 			   start, start + length, vm->top);
320 }
321 
322 static void __gen8_ppgtt_alloc(struct i915_address_space * const vm,
323 			       struct i915_vm_pt_stash *stash,
324 			       struct i915_page_directory * const pd,
325 			       u64 * const start, const u64 end, int lvl)
326 {
327 	unsigned int idx, len;
328 
329 	GEM_BUG_ON(end > vm->total >> GEN8_PTE_SHIFT);
330 
331 	len = gen8_pd_range(*start, end, lvl--, &idx);
332 	GTT_TRACE("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d }\n",
333 		  __func__, vm, lvl + 1, *start, end,
334 		  idx, len, atomic_read(px_used(pd)));
335 	GEM_BUG_ON(!len || (idx + len - 1) >> gen8_pd_shift(1));
336 
337 	spin_lock(&pd->lock);
338 	GEM_BUG_ON(!atomic_read(px_used(pd))); /* Must be pinned! */
339 	do {
340 		struct i915_page_table *pt = pd->entry[idx];
341 
342 		if (!pt) {
343 			spin_unlock(&pd->lock);
344 
345 			GTT_TRACE("%s(%p):{ lvl:%d, idx:%d } allocating new tree\n",
346 				  __func__, vm, lvl + 1, idx);
347 
348 			pt = stash->pt[!!lvl];
349 			__i915_gem_object_pin_pages(pt->base);
350 
351 			fill_px(pt, vm->scratch[lvl]->encode);
352 
353 			spin_lock(&pd->lock);
354 			if (likely(!pd->entry[idx])) {
355 				stash->pt[!!lvl] = pt->stash;
356 				atomic_set(&pt->used, 0);
357 				set_pd_entry(pd, idx, pt);
358 			} else {
359 				pt = pd->entry[idx];
360 			}
361 		}
362 
363 		if (lvl) {
364 			atomic_inc(&pt->used);
365 			spin_unlock(&pd->lock);
366 
367 			__gen8_ppgtt_alloc(vm, stash,
368 					   as_pd(pt), start, end, lvl);
369 
370 			spin_lock(&pd->lock);
371 			atomic_dec(&pt->used);
372 			GEM_BUG_ON(!atomic_read(&pt->used));
373 		} else {
374 			unsigned int count = gen8_pt_count(*start, end);
375 
376 			GTT_TRACE("%s(%p):{ lvl:%d, start:%llx, end:%llx, idx:%d, len:%d, used:%d } inserting pte\n",
377 				  __func__, vm, lvl, *start, end,
378 				  gen8_pd_index(*start, 0), count,
379 				  atomic_read(&pt->used));
380 
381 			atomic_add(count, &pt->used);
382 			/* All other pdes may be simultaneously removed */
383 			GEM_BUG_ON(atomic_read(&pt->used) > NALLOC * I915_PDES);
384 			*start += count;
385 		}
386 	} while (idx++, --len);
387 	spin_unlock(&pd->lock);
388 }
389 
390 static void gen8_ppgtt_alloc(struct i915_address_space *vm,
391 			     struct i915_vm_pt_stash *stash,
392 			     u64 start, u64 length)
393 {
394 	GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT)));
395 	GEM_BUG_ON(!IS_ALIGNED(length, BIT_ULL(GEN8_PTE_SHIFT)));
396 	GEM_BUG_ON(range_overflows(start, length, vm->total));
397 
398 	start >>= GEN8_PTE_SHIFT;
399 	length >>= GEN8_PTE_SHIFT;
400 	GEM_BUG_ON(length == 0);
401 
402 	__gen8_ppgtt_alloc(vm, stash, i915_vm_to_ppgtt(vm)->pd,
403 			   &start, start + length, vm->top);
404 }
405 
406 static void __gen8_ppgtt_foreach(struct i915_address_space *vm,
407 				 struct i915_page_directory *pd,
408 				 u64 *start, u64 end, int lvl,
409 				 void (*fn)(struct i915_address_space *vm,
410 					    struct i915_page_table *pt,
411 					    void *data),
412 				 void *data)
413 {
414 	unsigned int idx, len;
415 
416 	len = gen8_pd_range(*start, end, lvl--, &idx);
417 
418 	spin_lock(&pd->lock);
419 	do {
420 		struct i915_page_table *pt = pd->entry[idx];
421 
422 		atomic_inc(&pt->used);
423 		spin_unlock(&pd->lock);
424 
425 		if (lvl) {
426 			__gen8_ppgtt_foreach(vm, as_pd(pt), start, end, lvl,
427 					     fn, data);
428 		} else {
429 			fn(vm, pt, data);
430 			*start += gen8_pt_count(*start, end);
431 		}
432 
433 		spin_lock(&pd->lock);
434 		atomic_dec(&pt->used);
435 	} while (idx++, --len);
436 	spin_unlock(&pd->lock);
437 }
438 
439 static void gen8_ppgtt_foreach(struct i915_address_space *vm,
440 			       u64 start, u64 length,
441 			       void (*fn)(struct i915_address_space *vm,
442 					  struct i915_page_table *pt,
443 					  void *data),
444 			       void *data)
445 {
446 	start >>= GEN8_PTE_SHIFT;
447 	length >>= GEN8_PTE_SHIFT;
448 
449 	__gen8_ppgtt_foreach(vm, i915_vm_to_ppgtt(vm)->pd,
450 			     &start, start + length, vm->top,
451 			     fn, data);
452 }
453 
454 static __always_inline u64
455 gen8_ppgtt_insert_pte(struct i915_ppgtt *ppgtt,
456 		      struct i915_page_directory *pdp,
457 		      struct sgt_dma *iter,
458 		      u64 idx,
459 		      unsigned int pat_index,
460 		      u32 flags)
461 {
462 	struct i915_page_directory *pd;
463 	const gen8_pte_t pte_encode = ppgtt->vm.pte_encode(0, pat_index, flags);
464 	gen8_pte_t *vaddr;
465 
466 	pd = i915_pd_entry(pdp, gen8_pd_index(idx, 2));
467 	vaddr = px_vaddr(i915_pt_entry(pd, gen8_pd_index(idx, 1)));
468 	do {
469 		GEM_BUG_ON(sg_dma_len(iter->sg) < I915_GTT_PAGE_SIZE);
470 		vaddr[gen8_pd_index(idx, 0)] = pte_encode | iter->dma;
471 
472 		iter->dma += I915_GTT_PAGE_SIZE;
473 		if (iter->dma >= iter->max) {
474 			iter->sg = __sg_next(iter->sg);
475 			if (!iter->sg || sg_dma_len(iter->sg) == 0) {
476 				idx = 0;
477 				break;
478 			}
479 
480 			iter->dma = sg_dma_address(iter->sg);
481 			iter->max = iter->dma + sg_dma_len(iter->sg);
482 		}
483 
484 		if (gen8_pd_index(++idx, 0) == 0) {
485 			if (gen8_pd_index(idx, 1) == 0) {
486 				/* Limited by sg length for 3lvl */
487 				if (gen8_pd_index(idx, 2) == 0)
488 					break;
489 
490 				pd = pdp->entry[gen8_pd_index(idx, 2)];
491 			}
492 
493 			drm_clflush_virt_range(vaddr, PAGE_SIZE);
494 			vaddr = px_vaddr(i915_pt_entry(pd, gen8_pd_index(idx, 1)));
495 		}
496 	} while (1);
497 	drm_clflush_virt_range(vaddr, PAGE_SIZE);
498 
499 	return idx;
500 }
501 
502 static void
503 xehp_ppgtt_insert_huge(struct i915_address_space *vm,
504 		       struct i915_vma_resource *vma_res,
505 		       struct sgt_dma *iter,
506 		       unsigned int pat_index,
507 		       u32 flags)
508 {
509 	const gen8_pte_t pte_encode = vm->pte_encode(0, pat_index, flags);
510 	unsigned int rem = sg_dma_len(iter->sg);
511 	u64 start = vma_res->start;
512 	u64 end = start + vma_res->vma_size;
513 
514 	GEM_BUG_ON(!i915_vm_is_4lvl(vm));
515 
516 	do {
517 		struct i915_page_directory * const pdp =
518 			gen8_pdp_for_page_address(vm, start);
519 		struct i915_page_directory * const pd =
520 			i915_pd_entry(pdp, __gen8_pte_index(start, 2));
521 		struct i915_page_table *pt =
522 			i915_pt_entry(pd, __gen8_pte_index(start, 1));
523 		gen8_pte_t encode = pte_encode;
524 		unsigned int page_size;
525 		gen8_pte_t *vaddr;
526 		u16 index, max, nent, i;
527 
528 		max = I915_PDES;
529 		nent = 1;
530 
531 		if (vma_res->bi.page_sizes.sg & I915_GTT_PAGE_SIZE_2M &&
532 		    IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_2M) &&
533 		    rem >= I915_GTT_PAGE_SIZE_2M &&
534 		    !__gen8_pte_index(start, 0)) {
535 			index = __gen8_pte_index(start, 1);
536 			encode |= GEN8_PDE_PS_2M;
537 			page_size = I915_GTT_PAGE_SIZE_2M;
538 
539 			vaddr = px_vaddr(pd);
540 		} else {
541 			index =  __gen8_pte_index(start, 0);
542 			page_size = I915_GTT_PAGE_SIZE;
543 
544 			if (vma_res->bi.page_sizes.sg & I915_GTT_PAGE_SIZE_64K) {
545 				/*
546 				 * Device local-memory on these platforms should
547 				 * always use 64K pages or larger (including GTT
548 				 * alignment), therefore if we know the whole
549 				 * page-table needs to be filled we can always
550 				 * safely use the compact-layout. Otherwise fall
551 				 * back to the TLB hint with PS64. If this is
552 				 * system memory we only bother with PS64.
553 				 */
554 				if ((encode & GEN12_PPGTT_PTE_LM) &&
555 				    end - start >= SZ_2M && !index) {
556 					index = __gen8_pte_index(start, 0) / 16;
557 					page_size = I915_GTT_PAGE_SIZE_64K;
558 
559 					max /= 16;
560 
561 					vaddr = px_vaddr(pd);
562 					vaddr[__gen8_pte_index(start, 1)] |= GEN12_PDE_64K;
563 
564 					pt->is_compact = true;
565 				} else if (IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) &&
566 					   rem >= I915_GTT_PAGE_SIZE_64K &&
567 					   !(index % 16)) {
568 					encode |= GEN12_PTE_PS64;
569 					page_size = I915_GTT_PAGE_SIZE_64K;
570 					nent = 16;
571 				}
572 			}
573 
574 			vaddr = px_vaddr(pt);
575 		}
576 
577 		do {
578 			GEM_BUG_ON(rem < page_size);
579 
580 			for (i = 0; i < nent; i++) {
581 				vaddr[index++] =
582 					encode | (iter->dma + i *
583 						  I915_GTT_PAGE_SIZE);
584 			}
585 
586 			start += page_size;
587 			iter->dma += page_size;
588 			rem -= page_size;
589 			if (iter->dma >= iter->max) {
590 				iter->sg = __sg_next(iter->sg);
591 				if (!iter->sg)
592 					break;
593 
594 				rem = sg_dma_len(iter->sg);
595 				if (!rem)
596 					break;
597 
598 				iter->dma = sg_dma_address(iter->sg);
599 				iter->max = iter->dma + rem;
600 
601 				if (unlikely(!IS_ALIGNED(iter->dma, page_size)))
602 					break;
603 			}
604 		} while (rem >= page_size && index < max);
605 
606 		drm_clflush_virt_range(vaddr, PAGE_SIZE);
607 		vma_res->page_sizes_gtt |= page_size;
608 	} while (iter->sg && sg_dma_len(iter->sg));
609 }
610 
611 static void gen8_ppgtt_insert_huge(struct i915_address_space *vm,
612 				   struct i915_vma_resource *vma_res,
613 				   struct sgt_dma *iter,
614 				   unsigned int pat_index,
615 				   u32 flags)
616 {
617 	const gen8_pte_t pte_encode = vm->pte_encode(0, pat_index, flags);
618 	unsigned int rem = sg_dma_len(iter->sg);
619 	u64 start = vma_res->start;
620 
621 	GEM_BUG_ON(!i915_vm_is_4lvl(vm));
622 
623 	do {
624 		struct i915_page_directory * const pdp =
625 			gen8_pdp_for_page_address(vm, start);
626 		struct i915_page_directory * const pd =
627 			i915_pd_entry(pdp, __gen8_pte_index(start, 2));
628 		gen8_pte_t encode = pte_encode;
629 		unsigned int maybe_64K = -1;
630 		unsigned int page_size;
631 		gen8_pte_t *vaddr;
632 		u16 index;
633 
634 		if (vma_res->bi.page_sizes.sg & I915_GTT_PAGE_SIZE_2M &&
635 		    IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_2M) &&
636 		    rem >= I915_GTT_PAGE_SIZE_2M &&
637 		    !__gen8_pte_index(start, 0)) {
638 			index = __gen8_pte_index(start, 1);
639 			encode |= GEN8_PDE_PS_2M;
640 			page_size = I915_GTT_PAGE_SIZE_2M;
641 
642 			vaddr = px_vaddr(pd);
643 		} else {
644 			struct i915_page_table *pt =
645 				i915_pt_entry(pd, __gen8_pte_index(start, 1));
646 
647 			index = __gen8_pte_index(start, 0);
648 			page_size = I915_GTT_PAGE_SIZE;
649 
650 			if (!index &&
651 			    vma_res->bi.page_sizes.sg & I915_GTT_PAGE_SIZE_64K &&
652 			    IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) &&
653 			    (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) ||
654 			     rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE))
655 				maybe_64K = __gen8_pte_index(start, 1);
656 
657 			vaddr = px_vaddr(pt);
658 		}
659 
660 		do {
661 			GEM_BUG_ON(sg_dma_len(iter->sg) < page_size);
662 			vaddr[index++] = encode | iter->dma;
663 
664 			start += page_size;
665 			iter->dma += page_size;
666 			rem -= page_size;
667 			if (iter->dma >= iter->max) {
668 				iter->sg = __sg_next(iter->sg);
669 				if (!iter->sg)
670 					break;
671 
672 				rem = sg_dma_len(iter->sg);
673 				if (!rem)
674 					break;
675 
676 				iter->dma = sg_dma_address(iter->sg);
677 				iter->max = iter->dma + rem;
678 
679 				if (maybe_64K != -1 && index < I915_PDES &&
680 				    !(IS_ALIGNED(iter->dma, I915_GTT_PAGE_SIZE_64K) &&
681 				      (IS_ALIGNED(rem, I915_GTT_PAGE_SIZE_64K) ||
682 				       rem >= (I915_PDES - index) * I915_GTT_PAGE_SIZE)))
683 					maybe_64K = -1;
684 
685 				if (unlikely(!IS_ALIGNED(iter->dma, page_size)))
686 					break;
687 			}
688 		} while (rem >= page_size && index < I915_PDES);
689 
690 		drm_clflush_virt_range(vaddr, PAGE_SIZE);
691 
692 		/*
693 		 * Is it safe to mark the 2M block as 64K? -- Either we have
694 		 * filled whole page-table with 64K entries, or filled part of
695 		 * it and have reached the end of the sg table and we have
696 		 * enough padding.
697 		 */
698 		if (maybe_64K != -1 &&
699 		    (index == I915_PDES ||
700 		     (i915_vm_has_scratch_64K(vm) &&
701 		      !iter->sg && IS_ALIGNED(vma_res->start +
702 					      vma_res->node_size,
703 					      I915_GTT_PAGE_SIZE_2M)))) {
704 			vaddr = px_vaddr(pd);
705 			vaddr[maybe_64K] |= GEN8_PDE_IPS_64K;
706 			drm_clflush_virt_range(vaddr, PAGE_SIZE);
707 			page_size = I915_GTT_PAGE_SIZE_64K;
708 
709 			/*
710 			 * We write all 4K page entries, even when using 64K
711 			 * pages. In order to verify that the HW isn't cheating
712 			 * by using the 4K PTE instead of the 64K PTE, we want
713 			 * to remove all the surplus entries. If the HW skipped
714 			 * the 64K PTE, it will read/write into the scratch page
715 			 * instead - which we detect as missing results during
716 			 * selftests.
717 			 */
718 			if (I915_SELFTEST_ONLY(vm->scrub_64K)) {
719 				u16 i;
720 
721 				encode = vm->scratch[0]->encode;
722 				vaddr = px_vaddr(i915_pt_entry(pd, maybe_64K));
723 
724 				for (i = 1; i < index; i += 16)
725 					memset64(vaddr + i, encode, 15);
726 
727 				drm_clflush_virt_range(vaddr, PAGE_SIZE);
728 			}
729 		}
730 
731 		vma_res->page_sizes_gtt |= page_size;
732 	} while (iter->sg && sg_dma_len(iter->sg));
733 }
734 
735 static void gen8_ppgtt_insert(struct i915_address_space *vm,
736 			      struct i915_vma_resource *vma_res,
737 			      unsigned int pat_index,
738 			      u32 flags)
739 {
740 	struct i915_ppgtt * const ppgtt = i915_vm_to_ppgtt(vm);
741 	struct sgt_dma iter = sgt_dma(vma_res);
742 
743 	if (vma_res->bi.page_sizes.sg > I915_GTT_PAGE_SIZE) {
744 		if (GRAPHICS_VER_FULL(vm->i915) >= IP_VER(12, 55))
745 			xehp_ppgtt_insert_huge(vm, vma_res, &iter, pat_index, flags);
746 		else
747 			gen8_ppgtt_insert_huge(vm, vma_res, &iter, pat_index, flags);
748 	} else  {
749 		u64 idx = vma_res->start >> GEN8_PTE_SHIFT;
750 
751 		do {
752 			struct i915_page_directory * const pdp =
753 				gen8_pdp_for_page_index(vm, idx);
754 
755 			idx = gen8_ppgtt_insert_pte(ppgtt, pdp, &iter, idx,
756 						    pat_index, flags);
757 		} while (idx);
758 
759 		vma_res->page_sizes_gtt = I915_GTT_PAGE_SIZE;
760 	}
761 }
762 
763 static void gen8_ppgtt_insert_entry(struct i915_address_space *vm,
764 				    dma_addr_t addr,
765 				    u64 offset,
766 				    unsigned int pat_index,
767 				    u32 flags)
768 {
769 	u64 idx = offset >> GEN8_PTE_SHIFT;
770 	struct i915_page_directory * const pdp =
771 		gen8_pdp_for_page_index(vm, idx);
772 	struct i915_page_directory *pd =
773 		i915_pd_entry(pdp, gen8_pd_index(idx, 2));
774 	struct i915_page_table *pt = i915_pt_entry(pd, gen8_pd_index(idx, 1));
775 	gen8_pte_t *vaddr;
776 
777 	GEM_BUG_ON(pt->is_compact);
778 
779 	vaddr = px_vaddr(pt);
780 	vaddr[gen8_pd_index(idx, 0)] = vm->pte_encode(addr, pat_index, flags);
781 	drm_clflush_virt_range(&vaddr[gen8_pd_index(idx, 0)], sizeof(*vaddr));
782 }
783 
784 static void xehp_ppgtt_insert_entry_lm(struct i915_address_space *vm,
785 				       dma_addr_t addr,
786 				       u64 offset,
787 				       unsigned int pat_index,
788 				       u32 flags)
789 {
790 	u64 idx = offset >> GEN8_PTE_SHIFT;
791 	struct i915_page_directory * const pdp =
792 		gen8_pdp_for_page_index(vm, idx);
793 	struct i915_page_directory *pd =
794 		i915_pd_entry(pdp, gen8_pd_index(idx, 2));
795 	struct i915_page_table *pt = i915_pt_entry(pd, gen8_pd_index(idx, 1));
796 	gen8_pte_t *vaddr;
797 
798 	GEM_BUG_ON(!IS_ALIGNED(addr, SZ_64K));
799 	GEM_BUG_ON(!IS_ALIGNED(offset, SZ_64K));
800 
801 	/* XXX: we don't strictly need to use this layout */
802 
803 	if (!pt->is_compact) {
804 		vaddr = px_vaddr(pd);
805 		vaddr[gen8_pd_index(idx, 1)] |= GEN12_PDE_64K;
806 		pt->is_compact = true;
807 	}
808 
809 	vaddr = px_vaddr(pt);
810 	vaddr[gen8_pd_index(idx, 0) / 16] = vm->pte_encode(addr, pat_index, flags);
811 }
812 
813 static void xehp_ppgtt_insert_entry(struct i915_address_space *vm,
814 				    dma_addr_t addr,
815 				    u64 offset,
816 				    unsigned int pat_index,
817 				    u32 flags)
818 {
819 	if (flags & PTE_LM)
820 		return xehp_ppgtt_insert_entry_lm(vm, addr, offset,
821 						  pat_index, flags);
822 
823 	return gen8_ppgtt_insert_entry(vm, addr, offset, pat_index, flags);
824 }
825 
826 static int gen8_init_scratch(struct i915_address_space *vm)
827 {
828 	u32 pte_flags;
829 	int ret;
830 	int i;
831 
832 	/*
833 	 * If everybody agrees to not to write into the scratch page,
834 	 * we can reuse it for all vm, keeping contexts and processes separate.
835 	 */
836 	if (vm->has_read_only && vm->gt->vm && !i915_is_ggtt(vm->gt->vm)) {
837 		struct i915_address_space *clone = vm->gt->vm;
838 
839 		GEM_BUG_ON(!clone->has_read_only);
840 
841 		vm->scratch_order = clone->scratch_order;
842 		for (i = 0; i <= vm->top; i++)
843 			vm->scratch[i] = i915_gem_object_get(clone->scratch[i]);
844 
845 		return 0;
846 	}
847 
848 	ret = setup_scratch_page(vm);
849 	if (ret)
850 		return ret;
851 
852 	pte_flags = vm->has_read_only;
853 	if (i915_gem_object_is_lmem(vm->scratch[0]))
854 		pte_flags |= PTE_LM;
855 
856 	vm->scratch[0]->encode =
857 		vm->pte_encode(px_dma(vm->scratch[0]),
858 			       i915_gem_get_pat_index(vm->i915,
859 						      I915_CACHE_NONE),
860 			       pte_flags);
861 
862 	for (i = 1; i <= vm->top; i++) {
863 		struct drm_i915_gem_object *obj;
864 
865 		obj = vm->alloc_pt_dma(vm, I915_GTT_PAGE_SIZE_4K);
866 		if (IS_ERR(obj)) {
867 			ret = PTR_ERR(obj);
868 			goto free_scratch;
869 		}
870 
871 		ret = map_pt_dma(vm, obj);
872 		if (ret) {
873 			i915_gem_object_put(obj);
874 			goto free_scratch;
875 		}
876 
877 		fill_px(obj, vm->scratch[i - 1]->encode);
878 		obj->encode = gen8_pde_encode(px_dma(obj), I915_CACHE_NONE);
879 
880 		vm->scratch[i] = obj;
881 	}
882 
883 	return 0;
884 
885 free_scratch:
886 	while (i--)
887 		i915_gem_object_put(vm->scratch[i]);
888 	vm->scratch[0] = NULL;
889 	return ret;
890 }
891 
892 static int gen8_preallocate_top_level_pdp(struct i915_ppgtt *ppgtt)
893 {
894 	struct i915_address_space *vm = &ppgtt->vm;
895 	struct i915_page_directory *pd = ppgtt->pd;
896 	unsigned int idx;
897 
898 	GEM_BUG_ON(vm->top != 2);
899 	GEM_BUG_ON(gen8_pd_top_count(vm) != GEN8_3LVL_PDPES);
900 
901 	for (idx = 0; idx < GEN8_3LVL_PDPES; idx++) {
902 		struct i915_page_directory *pde;
903 		int err;
904 
905 		pde = alloc_pd(vm);
906 		if (IS_ERR(pde))
907 			return PTR_ERR(pde);
908 
909 		err = map_pt_dma(vm, pde->pt.base);
910 		if (err) {
911 			free_pd(vm, pde);
912 			return err;
913 		}
914 
915 		fill_px(pde, vm->scratch[1]->encode);
916 		set_pd_entry(pd, idx, pde);
917 		atomic_inc(px_used(pde)); /* keep pinned */
918 	}
919 	wmb();
920 
921 	return 0;
922 }
923 
924 static struct i915_page_directory *
925 gen8_alloc_top_pd(struct i915_address_space *vm)
926 {
927 	const unsigned int count = gen8_pd_top_count(vm);
928 	struct i915_page_directory *pd;
929 	int err;
930 
931 	GEM_BUG_ON(count > I915_PDES);
932 
933 	pd = __alloc_pd(count);
934 	if (unlikely(!pd))
935 		return ERR_PTR(-ENOMEM);
936 
937 	pd->pt.base = vm->alloc_pt_dma(vm, I915_GTT_PAGE_SIZE_4K);
938 	if (IS_ERR(pd->pt.base)) {
939 		err = PTR_ERR(pd->pt.base);
940 		pd->pt.base = NULL;
941 		goto err_pd;
942 	}
943 
944 	err = map_pt_dma(vm, pd->pt.base);
945 	if (err)
946 		goto err_pd;
947 
948 	fill_page_dma(px_base(pd), vm->scratch[vm->top]->encode, count);
949 	atomic_inc(px_used(pd)); /* mark as pinned */
950 	return pd;
951 
952 err_pd:
953 	free_pd(vm, pd);
954 	return ERR_PTR(err);
955 }
956 
957 static int gen8_init_rsvd(struct i915_address_space *vm)
958 {
959 	struct drm_i915_private *i915 = vm->i915;
960 	struct drm_i915_gem_object *obj;
961 	struct i915_vma *vma;
962 	int ret;
963 
964 	if (!intel_gt_needs_wa_16018031267(vm->gt))
965 		return 0;
966 
967 	/* The memory will be used only by GPU. */
968 	obj = i915_gem_object_create_lmem(i915, PAGE_SIZE,
969 					  I915_BO_ALLOC_VOLATILE |
970 					  I915_BO_ALLOC_GPU_ONLY);
971 	if (IS_ERR(obj))
972 		obj = i915_gem_object_create_internal(i915, PAGE_SIZE);
973 	if (IS_ERR(obj))
974 		return PTR_ERR(obj);
975 
976 	vma = i915_vma_instance(obj, vm, NULL);
977 	if (IS_ERR(vma)) {
978 		ret = PTR_ERR(vma);
979 		goto unref;
980 	}
981 
982 	ret = i915_vma_pin(vma, 0, 0, PIN_USER | PIN_HIGH);
983 	if (ret)
984 		goto unref;
985 
986 	vm->rsvd.vma = i915_vma_make_unshrinkable(vma);
987 	vm->rsvd.obj = obj;
988 	vm->total -= vma->node.size;
989 	return 0;
990 unref:
991 	i915_gem_object_put(obj);
992 	return ret;
993 }
994 
995 /*
996  * GEN8 legacy ppgtt programming is accomplished through a max 4 PDP registers
997  * with a net effect resembling a 2-level page table in normal x86 terms. Each
998  * PDP represents 1GB of memory 4 * 512 * 512 * 4096 = 4GB legacy 32b address
999  * space.
1000  *
1001  */
1002 struct i915_ppgtt *gen8_ppgtt_create(struct intel_gt *gt,
1003 				     unsigned long lmem_pt_obj_flags)
1004 {
1005 	struct i915_page_directory *pd;
1006 	struct i915_ppgtt *ppgtt;
1007 	int err;
1008 
1009 	ppgtt = kzalloc(sizeof(*ppgtt), GFP_KERNEL);
1010 	if (!ppgtt)
1011 		return ERR_PTR(-ENOMEM);
1012 
1013 	ppgtt_init(ppgtt, gt, lmem_pt_obj_flags);
1014 	ppgtt->vm.top = i915_vm_is_4lvl(&ppgtt->vm) ? 3 : 2;
1015 	ppgtt->vm.pd_shift = ilog2(SZ_4K * SZ_4K / sizeof(gen8_pte_t));
1016 
1017 	/*
1018 	 * From bdw, there is hw support for read-only pages in the PPGTT.
1019 	 *
1020 	 * Gen11 has HSDES#:1807136187 unresolved. Disable ro support
1021 	 * for now.
1022 	 *
1023 	 * Gen12 has inherited the same read-only fault issue from gen11.
1024 	 */
1025 	ppgtt->vm.has_read_only = !IS_GRAPHICS_VER(gt->i915, 11, 12);
1026 
1027 	if (HAS_LMEM(gt->i915))
1028 		ppgtt->vm.alloc_pt_dma = alloc_pt_lmem;
1029 	else
1030 		ppgtt->vm.alloc_pt_dma = alloc_pt_dma;
1031 
1032 	/*
1033 	 * Using SMEM here instead of LMEM has the advantage of not reserving
1034 	 * high performance memory for a "never" used filler page. It also
1035 	 * removes the device access that would be required to initialise the
1036 	 * scratch page, reducing pressure on an even scarcer resource.
1037 	 */
1038 	ppgtt->vm.alloc_scratch_dma = alloc_pt_dma;
1039 
1040 	if (GRAPHICS_VER(gt->i915) >= 12)
1041 		ppgtt->vm.pte_encode = gen12_pte_encode;
1042 	else
1043 		ppgtt->vm.pte_encode = gen8_pte_encode;
1044 
1045 	ppgtt->vm.bind_async_flags = I915_VMA_LOCAL_BIND;
1046 	ppgtt->vm.insert_entries = gen8_ppgtt_insert;
1047 	if (HAS_64K_PAGES(gt->i915))
1048 		ppgtt->vm.insert_page = xehp_ppgtt_insert_entry;
1049 	else
1050 		ppgtt->vm.insert_page = gen8_ppgtt_insert_entry;
1051 	ppgtt->vm.allocate_va_range = gen8_ppgtt_alloc;
1052 	ppgtt->vm.clear_range = gen8_ppgtt_clear;
1053 	ppgtt->vm.foreach = gen8_ppgtt_foreach;
1054 	ppgtt->vm.cleanup = gen8_ppgtt_cleanup;
1055 
1056 	err = gen8_init_scratch(&ppgtt->vm);
1057 	if (err)
1058 		goto err_put;
1059 
1060 	pd = gen8_alloc_top_pd(&ppgtt->vm);
1061 	if (IS_ERR(pd)) {
1062 		err = PTR_ERR(pd);
1063 		goto err_put;
1064 	}
1065 	ppgtt->pd = pd;
1066 
1067 	if (!i915_vm_is_4lvl(&ppgtt->vm)) {
1068 		err = gen8_preallocate_top_level_pdp(ppgtt);
1069 		if (err)
1070 			goto err_put;
1071 	}
1072 
1073 	if (intel_vgpu_active(gt->i915))
1074 		gen8_ppgtt_notify_vgt(ppgtt, true);
1075 
1076 	err = gen8_init_rsvd(&ppgtt->vm);
1077 	if (err)
1078 		goto err_put;
1079 
1080 	return ppgtt;
1081 
1082 err_put:
1083 	i915_vm_put(&ppgtt->vm);
1084 	return ERR_PTR(err);
1085 }
1086