xref: /linux/drivers/gpu/drm/xe/xe_ggtt.c (revision b615879dbfea6cf1236acbc3f2fb25ae84e07071)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2021 Intel Corporation
4  */
5 
6 #include "xe_ggtt.h"
7 
8 #include <kunit/visibility.h>
9 #include <linux/fault-inject.h>
10 #include <linux/io-64-nonatomic-lo-hi.h>
11 #include <linux/sizes.h>
12 
13 #include <drm/drm_drv.h>
14 #include <drm/drm_managed.h>
15 #include <drm/intel/i915_drm.h>
16 #include <generated/xe_wa_oob.h>
17 
18 #include "regs/xe_gt_regs.h"
19 #include "regs/xe_gtt_defs.h"
20 #include "regs/xe_regs.h"
21 #include "xe_assert.h"
22 #include "xe_bo.h"
23 #include "xe_device.h"
24 #include "xe_gt.h"
25 #include "xe_gt_printk.h"
26 #include "xe_map.h"
27 #include "xe_mmio.h"
28 #include "xe_pm.h"
29 #include "xe_res_cursor.h"
30 #include "xe_sriov.h"
31 #include "xe_tile_printk.h"
32 #include "xe_tile_sriov_vf.h"
33 #include "xe_tlb_inval.h"
34 #include "xe_wa.h"
35 #include "xe_wopcm.h"
36 
37 /**
38  * DOC: Global Graphics Translation Table (GGTT)
39  *
40  * Xe GGTT implements the support for a Global Virtual Address space that is used
41  * for resources that are accessible to privileged (i.e. kernel-mode) processes,
42  * and not tied to a specific user-level process. For example, the Graphics
43  * micro-Controller (GuC) and Display Engine (if present) utilize this Global
44  * address space.
45  *
46  * The Global GTT (GGTT) translates from the Global virtual address to a physical
47  * address that can be accessed by HW. The GGTT is a flat, single-level table.
48  *
49  * Xe implements a simplified version of the GGTT specifically managing only a
50  * certain range of it that goes from the Write Once Protected Content Memory (WOPCM)
51  * Layout to a predefined GUC_GGTT_TOP. This approach avoids complications related to
52  * the GuC (Graphics Microcontroller) hardware limitations. The GuC address space
53  * is limited on both ends of the GGTT, because the GuC shim HW redirects
54  * accesses to those addresses to other HW areas instead of going through the
55  * GGTT. On the bottom end, the GuC can't access offsets below the WOPCM size,
56  * while on the top side the limit is fixed at GUC_GGTT_TOP. To keep things
57  * simple, instead of checking each object to see if they are accessed by GuC or
58  * not, we just exclude those areas from the allocator. Additionally, to simplify
59  * the driver load, we use the maximum WOPCM size in this logic instead of the
60  * programmed one, so we don't need to wait until the actual size to be
61  * programmed is determined (which requires FW fetch) before initializing the
62  * GGTT. These simplifications might waste space in the GGTT (about 20-25 MBs
63  * depending on the platform) but we can live with this. Another benefit of this
64  * is the GuC bootrom can't access anything below the WOPCM max size so anything
65  * the bootrom needs to access (e.g. a RSA key) needs to be placed in the GGTT
66  * above the WOPCM max size. Starting the GGTT allocations above the WOPCM max
67  * give us the correct placement for free.
68  */
69 
70 static u64 xelp_ggtt_pte_flags(struct xe_bo *bo, u16 pat_index)
71 {
72 	u64 pte = XE_PAGE_PRESENT;
73 
74 	if (xe_bo_is_vram(bo) || xe_bo_is_stolen_devmem(bo))
75 		pte |= XE_GGTT_PTE_DM;
76 
77 	return pte;
78 }
79 
80 static u64 xelpg_ggtt_pte_flags(struct xe_bo *bo, u16 pat_index)
81 {
82 	struct xe_device *xe = xe_bo_device(bo);
83 	u64 pte;
84 
85 	pte = xelp_ggtt_pte_flags(bo, pat_index);
86 
87 	xe_assert(xe, pat_index <= 3);
88 
89 	if (pat_index & BIT(0))
90 		pte |= XELPG_GGTT_PTE_PAT0;
91 
92 	if (pat_index & BIT(1))
93 		pte |= XELPG_GGTT_PTE_PAT1;
94 
95 	return pte;
96 }
97 
98 static unsigned int probe_gsm_size(struct pci_dev *pdev)
99 {
100 	u16 gmch_ctl, ggms;
101 
102 	pci_read_config_word(pdev, SNB_GMCH_CTRL, &gmch_ctl);
103 	ggms = (gmch_ctl >> BDW_GMCH_GGMS_SHIFT) & BDW_GMCH_GGMS_MASK;
104 	return ggms ? SZ_1M << ggms : 0;
105 }
106 
107 static void ggtt_update_access_counter(struct xe_ggtt *ggtt)
108 {
109 	struct xe_tile *tile = ggtt->tile;
110 	struct xe_gt *affected_gt = XE_GT_WA(tile->primary_gt, 22019338487) ?
111 		tile->primary_gt : tile->media_gt;
112 	struct xe_mmio *mmio = &affected_gt->mmio;
113 	u32 max_gtt_writes = XE_GT_WA(ggtt->tile->primary_gt, 22019338487) ? 1100 : 63;
114 	/*
115 	 * Wa_22019338487: GMD_ID is a RO register, a dummy write forces gunit
116 	 * to wait for completion of prior GTT writes before letting this through.
117 	 * This needs to be done for all GGTT writes originating from the CPU.
118 	 */
119 	lockdep_assert_held(&ggtt->lock);
120 
121 	if ((++ggtt->access_count % max_gtt_writes) == 0) {
122 		xe_mmio_write32(mmio, GMD_ID, 0x0);
123 		ggtt->access_count = 0;
124 	}
125 }
126 
127 static void xe_ggtt_set_pte(struct xe_ggtt *ggtt, u64 addr, u64 pte)
128 {
129 	xe_tile_assert(ggtt->tile, !(addr & XE_PTE_MASK));
130 	xe_tile_assert(ggtt->tile, addr < ggtt->size);
131 
132 	writeq(pte, &ggtt->gsm[addr >> XE_PTE_SHIFT]);
133 }
134 
135 static void xe_ggtt_set_pte_and_flush(struct xe_ggtt *ggtt, u64 addr, u64 pte)
136 {
137 	xe_ggtt_set_pte(ggtt, addr, pte);
138 	ggtt_update_access_counter(ggtt);
139 }
140 
141 static void xe_ggtt_clear(struct xe_ggtt *ggtt, u64 start, u64 size)
142 {
143 	u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[XE_CACHE_WB];
144 	u64 end = start + size - 1;
145 	u64 scratch_pte;
146 
147 	xe_tile_assert(ggtt->tile, start < end);
148 
149 	if (ggtt->scratch)
150 		scratch_pte = xe_bo_addr(ggtt->scratch, 0, XE_PAGE_SIZE) |
151 			      ggtt->pt_ops->pte_encode_flags(ggtt->scratch,
152 							     pat_index);
153 	else
154 		scratch_pte = 0;
155 
156 	while (start < end) {
157 		ggtt->pt_ops->ggtt_set_pte(ggtt, start, scratch_pte);
158 		start += XE_PAGE_SIZE;
159 	}
160 }
161 
162 /**
163  * xe_ggtt_alloc - Allocate a GGTT for a given &xe_tile
164  * @tile: &xe_tile
165  *
166  * Allocates a &xe_ggtt for a given tile.
167  *
168  * Return: &xe_ggtt on success, or NULL when out of memory.
169  */
170 struct xe_ggtt *xe_ggtt_alloc(struct xe_tile *tile)
171 {
172 	struct xe_ggtt *ggtt = drmm_kzalloc(&tile_to_xe(tile)->drm, sizeof(*ggtt), GFP_KERNEL);
173 	if (ggtt)
174 		ggtt->tile = tile;
175 	return ggtt;
176 }
177 
178 static void ggtt_fini_early(struct drm_device *drm, void *arg)
179 {
180 	struct xe_ggtt *ggtt = arg;
181 
182 	destroy_workqueue(ggtt->wq);
183 	mutex_destroy(&ggtt->lock);
184 	drm_mm_takedown(&ggtt->mm);
185 }
186 
187 static void ggtt_fini(void *arg)
188 {
189 	struct xe_ggtt *ggtt = arg;
190 
191 	ggtt->scratch = NULL;
192 }
193 
194 #ifdef CONFIG_LOCKDEP
195 void xe_ggtt_might_lock(struct xe_ggtt *ggtt)
196 {
197 	might_lock(&ggtt->lock);
198 }
199 #endif
200 
201 static void primelockdep(struct xe_ggtt *ggtt)
202 {
203 	if (!IS_ENABLED(CONFIG_LOCKDEP))
204 		return;
205 
206 	fs_reclaim_acquire(GFP_KERNEL);
207 	might_lock(&ggtt->lock);
208 	fs_reclaim_release(GFP_KERNEL);
209 }
210 
211 static const struct xe_ggtt_pt_ops xelp_pt_ops = {
212 	.pte_encode_flags = xelp_ggtt_pte_flags,
213 	.ggtt_set_pte = xe_ggtt_set_pte,
214 };
215 
216 static const struct xe_ggtt_pt_ops xelpg_pt_ops = {
217 	.pte_encode_flags = xelpg_ggtt_pte_flags,
218 	.ggtt_set_pte = xe_ggtt_set_pte,
219 };
220 
221 static const struct xe_ggtt_pt_ops xelpg_pt_wa_ops = {
222 	.pte_encode_flags = xelpg_ggtt_pte_flags,
223 	.ggtt_set_pte = xe_ggtt_set_pte_and_flush,
224 };
225 
226 static void __xe_ggtt_init_early(struct xe_ggtt *ggtt, u32 reserved)
227 {
228 	drm_mm_init(&ggtt->mm, reserved,
229 		    ggtt->size - reserved);
230 	mutex_init(&ggtt->lock);
231 	primelockdep(ggtt);
232 }
233 
234 int xe_ggtt_init_kunit(struct xe_ggtt *ggtt, u32 reserved, u32 size)
235 {
236 	ggtt->size = size;
237 	__xe_ggtt_init_early(ggtt, reserved);
238 	return 0;
239 }
240 EXPORT_SYMBOL_IF_KUNIT(xe_ggtt_init_kunit);
241 
242 static void dev_fini_ggtt(void *arg)
243 {
244 	struct xe_ggtt *ggtt = arg;
245 
246 	drain_workqueue(ggtt->wq);
247 }
248 
249 /**
250  * xe_ggtt_init_early - Early GGTT initialization
251  * @ggtt: the &xe_ggtt to be initialized
252  *
253  * It allows to create new mappings usable by the GuC.
254  * Mappings are not usable by the HW engines, as it doesn't have scratch nor
255  * initial clear done to it yet. That will happen in the regular, non-early
256  * GGTT initialization.
257  *
258  * Return: 0 on success or a negative error code on failure.
259  */
260 int xe_ggtt_init_early(struct xe_ggtt *ggtt)
261 {
262 	struct xe_device *xe = tile_to_xe(ggtt->tile);
263 	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
264 	unsigned int gsm_size;
265 	int err;
266 
267 	if (IS_SRIOV_VF(xe) || GRAPHICS_VERx100(xe) >= 1250)
268 		gsm_size = SZ_8M; /* GGTT is expected to be 4GiB */
269 	else
270 		gsm_size = probe_gsm_size(pdev);
271 
272 	if (gsm_size == 0) {
273 		xe_tile_err(ggtt->tile, "Hardware reported no preallocated GSM\n");
274 		return -ENOMEM;
275 	}
276 
277 	ggtt->gsm = ggtt->tile->mmio.regs + SZ_8M;
278 	ggtt->size = (gsm_size / 8) * (u64) XE_PAGE_SIZE;
279 
280 	if (IS_DGFX(xe) && xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K)
281 		ggtt->flags |= XE_GGTT_FLAGS_64K;
282 
283 	if (ggtt->size > GUC_GGTT_TOP)
284 		ggtt->size = GUC_GGTT_TOP;
285 
286 	if (GRAPHICS_VERx100(xe) >= 1270)
287 		ggtt->pt_ops = (ggtt->tile->media_gt &&
288 			       XE_GT_WA(ggtt->tile->media_gt, 22019338487)) ||
289 			       XE_GT_WA(ggtt->tile->primary_gt, 22019338487) ?
290 			       &xelpg_pt_wa_ops : &xelpg_pt_ops;
291 	else
292 		ggtt->pt_ops = &xelp_pt_ops;
293 
294 	ggtt->wq = alloc_workqueue("xe-ggtt-wq", 0, WQ_MEM_RECLAIM);
295 	__xe_ggtt_init_early(ggtt, xe_wopcm_size(xe));
296 
297 	err = drmm_add_action_or_reset(&xe->drm, ggtt_fini_early, ggtt);
298 	if (err)
299 		return err;
300 
301 	err = devm_add_action_or_reset(xe->drm.dev, dev_fini_ggtt, ggtt);
302 	if (err)
303 		return err;
304 
305 	if (IS_SRIOV_VF(xe)) {
306 		err = xe_tile_sriov_vf_prepare_ggtt(ggtt->tile);
307 		if (err)
308 			return err;
309 	}
310 
311 	return 0;
312 }
313 ALLOW_ERROR_INJECTION(xe_ggtt_init_early, ERRNO); /* See xe_pci_probe() */
314 
315 static void xe_ggtt_invalidate(struct xe_ggtt *ggtt);
316 
317 static void xe_ggtt_initial_clear(struct xe_ggtt *ggtt)
318 {
319 	struct drm_mm_node *hole;
320 	u64 start, end;
321 
322 	/* Display may have allocated inside ggtt, so be careful with clearing here */
323 	mutex_lock(&ggtt->lock);
324 	drm_mm_for_each_hole(hole, &ggtt->mm, start, end)
325 		xe_ggtt_clear(ggtt, start, end - start);
326 
327 	xe_ggtt_invalidate(ggtt);
328 	mutex_unlock(&ggtt->lock);
329 }
330 
331 static void ggtt_node_remove(struct xe_ggtt_node *node)
332 {
333 	struct xe_ggtt *ggtt = node->ggtt;
334 	struct xe_device *xe = tile_to_xe(ggtt->tile);
335 	bool bound;
336 	int idx;
337 
338 	bound = drm_dev_enter(&xe->drm, &idx);
339 
340 	mutex_lock(&ggtt->lock);
341 	if (bound)
342 		xe_ggtt_clear(ggtt, node->base.start, node->base.size);
343 	drm_mm_remove_node(&node->base);
344 	node->base.size = 0;
345 	mutex_unlock(&ggtt->lock);
346 
347 	if (!bound)
348 		goto free_node;
349 
350 	if (node->invalidate_on_remove)
351 		xe_ggtt_invalidate(ggtt);
352 
353 	drm_dev_exit(idx);
354 
355 free_node:
356 	xe_ggtt_node_fini(node);
357 }
358 
359 static void ggtt_node_remove_work_func(struct work_struct *work)
360 {
361 	struct xe_ggtt_node *node = container_of(work, typeof(*node),
362 						 delayed_removal_work);
363 	struct xe_device *xe = tile_to_xe(node->ggtt->tile);
364 
365 	xe_pm_runtime_get(xe);
366 	ggtt_node_remove(node);
367 	xe_pm_runtime_put(xe);
368 }
369 
370 /**
371  * xe_ggtt_node_remove - Remove a &xe_ggtt_node from the GGTT
372  * @node: the &xe_ggtt_node to be removed
373  * @invalidate: if node needs invalidation upon removal
374  */
375 void xe_ggtt_node_remove(struct xe_ggtt_node *node, bool invalidate)
376 {
377 	struct xe_ggtt *ggtt;
378 	struct xe_device *xe;
379 
380 	if (!node || !node->ggtt)
381 		return;
382 
383 	ggtt = node->ggtt;
384 	xe = tile_to_xe(ggtt->tile);
385 
386 	node->invalidate_on_remove = invalidate;
387 
388 	if (xe_pm_runtime_get_if_active(xe)) {
389 		ggtt_node_remove(node);
390 		xe_pm_runtime_put(xe);
391 	} else {
392 		queue_work(ggtt->wq, &node->delayed_removal_work);
393 	}
394 }
395 
396 /**
397  * xe_ggtt_init - Regular non-early GGTT initialization
398  * @ggtt: the &xe_ggtt to be initialized
399  *
400  * Return: 0 on success or a negative error code on failure.
401  */
402 int xe_ggtt_init(struct xe_ggtt *ggtt)
403 {
404 	struct xe_device *xe = tile_to_xe(ggtt->tile);
405 	unsigned int flags;
406 	int err;
407 
408 	/*
409 	 * So we don't need to worry about 64K GGTT layout when dealing with
410 	 * scratch entries, rather keep the scratch page in system memory on
411 	 * platforms where 64K pages are needed for VRAM.
412 	 */
413 	flags = 0;
414 	if (ggtt->flags & XE_GGTT_FLAGS_64K)
415 		flags |= XE_BO_FLAG_SYSTEM;
416 	else
417 		flags |= XE_BO_FLAG_VRAM_IF_DGFX(ggtt->tile);
418 
419 	ggtt->scratch = xe_managed_bo_create_pin_map(xe, ggtt->tile, XE_PAGE_SIZE, flags);
420 	if (IS_ERR(ggtt->scratch)) {
421 		err = PTR_ERR(ggtt->scratch);
422 		goto err;
423 	}
424 
425 	xe_map_memset(xe, &ggtt->scratch->vmap, 0, 0, xe_bo_size(ggtt->scratch));
426 
427 	xe_ggtt_initial_clear(ggtt);
428 
429 	return devm_add_action_or_reset(xe->drm.dev, ggtt_fini, ggtt);
430 err:
431 	ggtt->scratch = NULL;
432 	return err;
433 }
434 
435 static void ggtt_invalidate_gt_tlb(struct xe_gt *gt)
436 {
437 	int err;
438 
439 	if (!gt)
440 		return;
441 
442 	err = xe_tlb_inval_ggtt(&gt->tlb_inval);
443 	xe_gt_WARN(gt, err, "Failed to invalidate GGTT (%pe)", ERR_PTR(err));
444 }
445 
446 static void xe_ggtt_invalidate(struct xe_ggtt *ggtt)
447 {
448 	struct xe_device *xe = tile_to_xe(ggtt->tile);
449 
450 	/*
451 	 * XXX: Barrier for GGTT pages. Unsure exactly why this required but
452 	 * without this LNL is having issues with the GuC reading scratch page
453 	 * vs. correct GGTT page. Not particularly a hot code path so blindly
454 	 * do a mmio read here which results in GuC reading correct GGTT page.
455 	 */
456 	xe_mmio_read32(xe_root_tile_mmio(xe), VF_CAP_REG);
457 
458 	/* Each GT in a tile has its own TLB to cache GGTT lookups */
459 	ggtt_invalidate_gt_tlb(ggtt->tile->primary_gt);
460 	ggtt_invalidate_gt_tlb(ggtt->tile->media_gt);
461 }
462 
463 static void xe_ggtt_dump_node(struct xe_ggtt *ggtt,
464 			      const struct drm_mm_node *node, const char *description)
465 {
466 	char buf[10];
467 
468 	if (IS_ENABLED(CONFIG_DRM_XE_DEBUG)) {
469 		string_get_size(node->size, 1, STRING_UNITS_2, buf, sizeof(buf));
470 		xe_tile_dbg(ggtt->tile, "GGTT %#llx-%#llx (%s) %s\n",
471 			    node->start, node->start + node->size, buf, description);
472 	}
473 }
474 
475 /**
476  * xe_ggtt_node_insert_balloon_locked - prevent allocation of specified GGTT addresses
477  * @node: the &xe_ggtt_node to hold reserved GGTT node
478  * @start: the starting GGTT address of the reserved region
479  * @end: then end GGTT address of the reserved region
480  *
481  * To be used in cases where ggtt->lock is already taken.
482  * Use xe_ggtt_node_remove_balloon_locked() to release a reserved GGTT node.
483  *
484  * Return: 0 on success or a negative error code on failure.
485  */
486 int xe_ggtt_node_insert_balloon_locked(struct xe_ggtt_node *node, u64 start, u64 end)
487 {
488 	struct xe_ggtt *ggtt = node->ggtt;
489 	int err;
490 
491 	xe_tile_assert(ggtt->tile, start < end);
492 	xe_tile_assert(ggtt->tile, IS_ALIGNED(start, XE_PAGE_SIZE));
493 	xe_tile_assert(ggtt->tile, IS_ALIGNED(end, XE_PAGE_SIZE));
494 	xe_tile_assert(ggtt->tile, !drm_mm_node_allocated(&node->base));
495 	lockdep_assert_held(&ggtt->lock);
496 
497 	node->base.color = 0;
498 	node->base.start = start;
499 	node->base.size = end - start;
500 
501 	err = drm_mm_reserve_node(&ggtt->mm, &node->base);
502 
503 	if (xe_tile_WARN(ggtt->tile, err, "Failed to balloon GGTT %#llx-%#llx (%pe)\n",
504 			 node->base.start, node->base.start + node->base.size, ERR_PTR(err)))
505 		return err;
506 
507 	xe_ggtt_dump_node(ggtt, &node->base, "balloon");
508 	return 0;
509 }
510 
511 /**
512  * xe_ggtt_node_remove_balloon_locked - release a reserved GGTT region
513  * @node: the &xe_ggtt_node with reserved GGTT region
514  *
515  * To be used in cases where ggtt->lock is already taken.
516  * See xe_ggtt_node_insert_balloon_locked() for details.
517  */
518 void xe_ggtt_node_remove_balloon_locked(struct xe_ggtt_node *node)
519 {
520 	if (!xe_ggtt_node_allocated(node))
521 		return;
522 
523 	lockdep_assert_held(&node->ggtt->lock);
524 
525 	xe_ggtt_dump_node(node->ggtt, &node->base, "remove-balloon");
526 
527 	drm_mm_remove_node(&node->base);
528 }
529 
530 static void xe_ggtt_assert_fit(struct xe_ggtt *ggtt, u64 start, u64 size)
531 {
532 	struct xe_tile *tile = ggtt->tile;
533 	struct xe_device *xe = tile_to_xe(tile);
534 	u64 __maybe_unused wopcm = xe_wopcm_size(xe);
535 
536 	xe_tile_assert(tile, start >= wopcm);
537 	xe_tile_assert(tile, start + size < ggtt->size - wopcm);
538 }
539 
540 /**
541  * xe_ggtt_shift_nodes_locked - Shift GGTT nodes to adjust for a change in usable address range.
542  * @ggtt: the &xe_ggtt struct instance
543  * @shift: change to the location of area provisioned for current VF
544  *
545  * This function moves all nodes from the GGTT VM, to a temp list. These nodes are expected
546  * to represent allocations in range formerly assigned to current VF, before the range changed.
547  * When the GGTT VM is completely clear of any nodes, they are re-added with shifted offsets.
548  *
549  * The function has no ability of failing - because it shifts existing nodes, without
550  * any additional processing. If the nodes were successfully existing at the old address,
551  * they will do the same at the new one. A fail inside this function would indicate that
552  * the list of nodes was either already damaged, or that the shift brings the address range
553  * outside of valid bounds. Both cases justify an assert rather than error code.
554  */
555 void xe_ggtt_shift_nodes_locked(struct xe_ggtt *ggtt, s64 shift)
556 {
557 	struct xe_tile *tile __maybe_unused = ggtt->tile;
558 	struct drm_mm_node *node, *tmpn;
559 	LIST_HEAD(temp_list_head);
560 
561 	lockdep_assert_held(&ggtt->lock);
562 
563 	if (IS_ENABLED(CONFIG_DRM_XE_DEBUG))
564 		drm_mm_for_each_node_safe(node, tmpn, &ggtt->mm)
565 			xe_ggtt_assert_fit(ggtt, node->start + shift, node->size);
566 
567 	drm_mm_for_each_node_safe(node, tmpn, &ggtt->mm) {
568 		drm_mm_remove_node(node);
569 		list_add(&node->node_list, &temp_list_head);
570 	}
571 
572 	list_for_each_entry_safe(node, tmpn, &temp_list_head, node_list) {
573 		list_del(&node->node_list);
574 		node->start += shift;
575 		drm_mm_reserve_node(&ggtt->mm, node);
576 		xe_tile_assert(tile, drm_mm_node_allocated(node));
577 	}
578 }
579 
580 /**
581  * xe_ggtt_node_insert_locked - Locked version to insert a &xe_ggtt_node into the GGTT
582  * @node: the &xe_ggtt_node to be inserted
583  * @size: size of the node
584  * @align: alignment constrain of the node
585  * @mm_flags: flags to control the node behavior
586  *
587  * It cannot be called without first having called xe_ggtt_init() once.
588  * To be used in cases where ggtt->lock is already taken.
589  *
590  * Return: 0 on success or a negative error code on failure.
591  */
592 int xe_ggtt_node_insert_locked(struct xe_ggtt_node *node,
593 			       u32 size, u32 align, u32 mm_flags)
594 {
595 	return drm_mm_insert_node_generic(&node->ggtt->mm, &node->base, size, align, 0,
596 					  mm_flags);
597 }
598 
599 /**
600  * xe_ggtt_node_insert - Insert a &xe_ggtt_node into the GGTT
601  * @node: the &xe_ggtt_node to be inserted
602  * @size: size of the node
603  * @align: alignment constrain of the node
604  *
605  * It cannot be called without first having called xe_ggtt_init() once.
606  *
607  * Return: 0 on success or a negative error code on failure.
608  */
609 int xe_ggtt_node_insert(struct xe_ggtt_node *node, u32 size, u32 align)
610 {
611 	int ret;
612 
613 	if (!node || !node->ggtt)
614 		return -ENOENT;
615 
616 	mutex_lock(&node->ggtt->lock);
617 	ret = xe_ggtt_node_insert_locked(node, size, align,
618 					 DRM_MM_INSERT_HIGH);
619 	mutex_unlock(&node->ggtt->lock);
620 
621 	return ret;
622 }
623 
624 /**
625  * xe_ggtt_node_init - Initialize %xe_ggtt_node struct
626  * @ggtt: the &xe_ggtt where the new node will later be inserted/reserved.
627  *
628  * This function will allocate the struct %xe_ggtt_node and return its pointer.
629  * This struct will then be freed after the node removal upon xe_ggtt_node_remove()
630  * or xe_ggtt_node_remove_balloon_locked().
631  * Having %xe_ggtt_node struct allocated doesn't mean that the node is already allocated
632  * in GGTT. Only the xe_ggtt_node_insert(), xe_ggtt_node_insert_locked(),
633  * xe_ggtt_node_insert_balloon_locked() will ensure the node is inserted or reserved in GGTT.
634  *
635  * Return: A pointer to %xe_ggtt_node struct on success. An ERR_PTR otherwise.
636  **/
637 struct xe_ggtt_node *xe_ggtt_node_init(struct xe_ggtt *ggtt)
638 {
639 	struct xe_ggtt_node *node = kzalloc(sizeof(*node), GFP_NOFS);
640 
641 	if (!node)
642 		return ERR_PTR(-ENOMEM);
643 
644 	INIT_WORK(&node->delayed_removal_work, ggtt_node_remove_work_func);
645 	node->ggtt = ggtt;
646 
647 	return node;
648 }
649 
650 /**
651  * xe_ggtt_node_fini - Forcebly finalize %xe_ggtt_node struct
652  * @node: the &xe_ggtt_node to be freed
653  *
654  * If anything went wrong with either xe_ggtt_node_insert(), xe_ggtt_node_insert_locked(),
655  * or xe_ggtt_node_insert_balloon_locked(); and this @node is not going to be reused, then,
656  * this function needs to be called to free the %xe_ggtt_node struct
657  **/
658 void xe_ggtt_node_fini(struct xe_ggtt_node *node)
659 {
660 	kfree(node);
661 }
662 
663 /**
664  * xe_ggtt_node_allocated - Check if node is allocated in GGTT
665  * @node: the &xe_ggtt_node to be inspected
666  *
667  * Return: True if allocated, False otherwise.
668  */
669 bool xe_ggtt_node_allocated(const struct xe_ggtt_node *node)
670 {
671 	if (!node || !node->ggtt)
672 		return false;
673 
674 	return drm_mm_node_allocated(&node->base);
675 }
676 
677 /**
678  * xe_ggtt_map_bo - Map the BO into GGTT
679  * @ggtt: the &xe_ggtt where node will be mapped
680  * @node: the &xe_ggtt_node where this BO is mapped
681  * @bo: the &xe_bo to be mapped
682  * @pat_index: Which pat_index to use.
683  */
684 void xe_ggtt_map_bo(struct xe_ggtt *ggtt, struct xe_ggtt_node *node,
685 		    struct xe_bo *bo, u16 pat_index)
686 {
687 
688 	u64 start, pte, end;
689 	struct xe_res_cursor cur;
690 
691 	if (XE_WARN_ON(!node))
692 		return;
693 
694 	start = node->base.start;
695 	end = start + xe_bo_size(bo);
696 
697 	pte = ggtt->pt_ops->pte_encode_flags(bo, pat_index);
698 	if (!xe_bo_is_vram(bo) && !xe_bo_is_stolen(bo)) {
699 		xe_assert(xe_bo_device(bo), bo->ttm.ttm);
700 
701 		for (xe_res_first_sg(xe_bo_sg(bo), 0, xe_bo_size(bo), &cur);
702 		     cur.remaining; xe_res_next(&cur, XE_PAGE_SIZE))
703 			ggtt->pt_ops->ggtt_set_pte(ggtt, end - cur.remaining,
704 						   pte | xe_res_dma(&cur));
705 	} else {
706 		/* Prepend GPU offset */
707 		pte |= vram_region_gpu_offset(bo->ttm.resource);
708 
709 		for (xe_res_first(bo->ttm.resource, 0, xe_bo_size(bo), &cur);
710 		     cur.remaining; xe_res_next(&cur, XE_PAGE_SIZE))
711 			ggtt->pt_ops->ggtt_set_pte(ggtt, end - cur.remaining,
712 						   pte + cur.start);
713 	}
714 }
715 
716 /**
717  * xe_ggtt_map_bo_unlocked - Restore a mapping of a BO into GGTT
718  * @ggtt: the &xe_ggtt where node will be mapped
719  * @bo: the &xe_bo to be mapped
720  *
721  * This is used to restore a GGTT mapping after suspend.
722  */
723 void xe_ggtt_map_bo_unlocked(struct xe_ggtt *ggtt, struct xe_bo *bo)
724 {
725 	u16 cache_mode = bo->flags & XE_BO_FLAG_NEEDS_UC ? XE_CACHE_NONE : XE_CACHE_WB;
726 	u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[cache_mode];
727 
728 	mutex_lock(&ggtt->lock);
729 	xe_ggtt_map_bo(ggtt, bo->ggtt_node[ggtt->tile->id], bo, pat_index);
730 	mutex_unlock(&ggtt->lock);
731 }
732 
733 static int __xe_ggtt_insert_bo_at(struct xe_ggtt *ggtt, struct xe_bo *bo,
734 				  u64 start, u64 end, struct drm_exec *exec)
735 {
736 	u64 alignment = bo->min_align > 0 ? bo->min_align : XE_PAGE_SIZE;
737 	u8 tile_id = ggtt->tile->id;
738 	int err;
739 
740 	if (xe_bo_is_vram(bo) && ggtt->flags & XE_GGTT_FLAGS_64K)
741 		alignment = SZ_64K;
742 
743 	if (XE_WARN_ON(bo->ggtt_node[tile_id])) {
744 		/* Someone's already inserted this BO in the GGTT */
745 		xe_tile_assert(ggtt->tile, bo->ggtt_node[tile_id]->base.size == xe_bo_size(bo));
746 		return 0;
747 	}
748 
749 	err = xe_bo_validate(bo, NULL, false, exec);
750 	if (err)
751 		return err;
752 
753 	xe_pm_runtime_get_noresume(tile_to_xe(ggtt->tile));
754 
755 	bo->ggtt_node[tile_id] = xe_ggtt_node_init(ggtt);
756 	if (IS_ERR(bo->ggtt_node[tile_id])) {
757 		err = PTR_ERR(bo->ggtt_node[tile_id]);
758 		bo->ggtt_node[tile_id] = NULL;
759 		goto out;
760 	}
761 
762 	mutex_lock(&ggtt->lock);
763 	err = drm_mm_insert_node_in_range(&ggtt->mm, &bo->ggtt_node[tile_id]->base,
764 					  xe_bo_size(bo), alignment, 0, start, end, 0);
765 	if (err) {
766 		xe_ggtt_node_fini(bo->ggtt_node[tile_id]);
767 		bo->ggtt_node[tile_id] = NULL;
768 	} else {
769 		u16 cache_mode = bo->flags & XE_BO_FLAG_NEEDS_UC ? XE_CACHE_NONE : XE_CACHE_WB;
770 		u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[cache_mode];
771 
772 		xe_ggtt_map_bo(ggtt, bo->ggtt_node[tile_id], bo, pat_index);
773 	}
774 	mutex_unlock(&ggtt->lock);
775 
776 	if (!err && bo->flags & XE_BO_FLAG_GGTT_INVALIDATE)
777 		xe_ggtt_invalidate(ggtt);
778 
779 out:
780 	xe_pm_runtime_put(tile_to_xe(ggtt->tile));
781 
782 	return err;
783 }
784 
785 /**
786  * xe_ggtt_insert_bo_at - Insert BO at a specific GGTT space
787  * @ggtt: the &xe_ggtt where bo will be inserted
788  * @bo: the &xe_bo to be inserted
789  * @start: address where it will be inserted
790  * @end: end of the range where it will be inserted
791  * @exec: The drm_exec transaction to use for exhaustive eviction.
792  *
793  * Return: 0 on success or a negative error code on failure.
794  */
795 int xe_ggtt_insert_bo_at(struct xe_ggtt *ggtt, struct xe_bo *bo,
796 			 u64 start, u64 end, struct drm_exec *exec)
797 {
798 	return __xe_ggtt_insert_bo_at(ggtt, bo, start, end, exec);
799 }
800 
801 /**
802  * xe_ggtt_insert_bo - Insert BO into GGTT
803  * @ggtt: the &xe_ggtt where bo will be inserted
804  * @bo: the &xe_bo to be inserted
805  * @exec: The drm_exec transaction to use for exhaustive eviction.
806  *
807  * Return: 0 on success or a negative error code on failure.
808  */
809 int xe_ggtt_insert_bo(struct xe_ggtt *ggtt, struct xe_bo *bo,
810 		      struct drm_exec *exec)
811 {
812 	return __xe_ggtt_insert_bo_at(ggtt, bo, 0, U64_MAX, exec);
813 }
814 
815 /**
816  * xe_ggtt_remove_bo - Remove a BO from the GGTT
817  * @ggtt: the &xe_ggtt where node will be removed
818  * @bo: the &xe_bo to be removed
819  */
820 void xe_ggtt_remove_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)
821 {
822 	u8 tile_id = ggtt->tile->id;
823 
824 	if (XE_WARN_ON(!bo->ggtt_node[tile_id]))
825 		return;
826 
827 	/* This BO is not currently in the GGTT */
828 	xe_tile_assert(ggtt->tile, bo->ggtt_node[tile_id]->base.size == xe_bo_size(bo));
829 
830 	xe_ggtt_node_remove(bo->ggtt_node[tile_id],
831 			    bo->flags & XE_BO_FLAG_GGTT_INVALIDATE);
832 }
833 
834 /**
835  * xe_ggtt_largest_hole - Largest GGTT hole
836  * @ggtt: the &xe_ggtt that will be inspected
837  * @alignment: minimum alignment
838  * @spare: If not NULL: in: desired memory size to be spared / out: Adjusted possible spare
839  *
840  * Return: size of the largest continuous GGTT region
841  */
842 u64 xe_ggtt_largest_hole(struct xe_ggtt *ggtt, u64 alignment, u64 *spare)
843 {
844 	const struct drm_mm *mm = &ggtt->mm;
845 	const struct drm_mm_node *entry;
846 	u64 hole_min_start = xe_wopcm_size(tile_to_xe(ggtt->tile));
847 	u64 hole_start, hole_end, hole_size;
848 	u64 max_hole = 0;
849 
850 	mutex_lock(&ggtt->lock);
851 
852 	drm_mm_for_each_hole(entry, mm, hole_start, hole_end) {
853 		hole_start = max(hole_start, hole_min_start);
854 		hole_start = ALIGN(hole_start, alignment);
855 		hole_end = ALIGN_DOWN(hole_end, alignment);
856 		if (hole_start >= hole_end)
857 			continue;
858 		hole_size = hole_end - hole_start;
859 		if (spare)
860 			*spare -= min3(*spare, hole_size, max_hole);
861 		max_hole = max(max_hole, hole_size);
862 	}
863 
864 	mutex_unlock(&ggtt->lock);
865 
866 	return max_hole;
867 }
868 
869 #ifdef CONFIG_PCI_IOV
870 static u64 xe_encode_vfid_pte(u16 vfid)
871 {
872 	return FIELD_PREP(GGTT_PTE_VFID, vfid) | XE_PAGE_PRESENT;
873 }
874 
875 static void xe_ggtt_assign_locked(struct xe_ggtt *ggtt, const struct drm_mm_node *node, u16 vfid)
876 {
877 	u64 start = node->start;
878 	u64 size = node->size;
879 	u64 end = start + size - 1;
880 	u64 pte = xe_encode_vfid_pte(vfid);
881 
882 	lockdep_assert_held(&ggtt->lock);
883 
884 	if (!drm_mm_node_allocated(node))
885 		return;
886 
887 	while (start < end) {
888 		ggtt->pt_ops->ggtt_set_pte(ggtt, start, pte);
889 		start += XE_PAGE_SIZE;
890 	}
891 
892 	xe_ggtt_invalidate(ggtt);
893 }
894 
895 /**
896  * xe_ggtt_assign - assign a GGTT region to the VF
897  * @node: the &xe_ggtt_node to update
898  * @vfid: the VF identifier
899  *
900  * This function is used by the PF driver to assign a GGTT region to the VF.
901  * In addition to PTE's VFID bits 11:2 also PRESENT bit 0 is set as on some
902  * platforms VFs can't modify that either.
903  */
904 void xe_ggtt_assign(const struct xe_ggtt_node *node, u16 vfid)
905 {
906 	mutex_lock(&node->ggtt->lock);
907 	xe_ggtt_assign_locked(node->ggtt, &node->base, vfid);
908 	mutex_unlock(&node->ggtt->lock);
909 }
910 #endif
911 
912 /**
913  * xe_ggtt_dump - Dump GGTT for debug
914  * @ggtt: the &xe_ggtt to be dumped
915  * @p: the &drm_mm_printer helper handle to be used to dump the information
916  *
917  * Return: 0 on success or a negative error code on failure.
918  */
919 int xe_ggtt_dump(struct xe_ggtt *ggtt, struct drm_printer *p)
920 {
921 	int err;
922 
923 	err = mutex_lock_interruptible(&ggtt->lock);
924 	if (err)
925 		return err;
926 
927 	drm_mm_print(&ggtt->mm, p);
928 	mutex_unlock(&ggtt->lock);
929 	return err;
930 }
931 
932 /**
933  * xe_ggtt_print_holes - Print holes
934  * @ggtt: the &xe_ggtt to be inspected
935  * @alignment: min alignment
936  * @p: the &drm_printer
937  *
938  * Print GGTT ranges that are available and return total size available.
939  *
940  * Return: Total available size.
941  */
942 u64 xe_ggtt_print_holes(struct xe_ggtt *ggtt, u64 alignment, struct drm_printer *p)
943 {
944 	const struct drm_mm *mm = &ggtt->mm;
945 	const struct drm_mm_node *entry;
946 	u64 hole_min_start = xe_wopcm_size(tile_to_xe(ggtt->tile));
947 	u64 hole_start, hole_end, hole_size;
948 	u64 total = 0;
949 	char buf[10];
950 
951 	mutex_lock(&ggtt->lock);
952 
953 	drm_mm_for_each_hole(entry, mm, hole_start, hole_end) {
954 		hole_start = max(hole_start, hole_min_start);
955 		hole_start = ALIGN(hole_start, alignment);
956 		hole_end = ALIGN_DOWN(hole_end, alignment);
957 		if (hole_start >= hole_end)
958 			continue;
959 		hole_size = hole_end - hole_start;
960 		total += hole_size;
961 
962 		string_get_size(hole_size, 1, STRING_UNITS_2, buf, sizeof(buf));
963 		drm_printf(p, "range:\t%#llx-%#llx\t(%s)\n",
964 			   hole_start, hole_end - 1, buf);
965 	}
966 
967 	mutex_unlock(&ggtt->lock);
968 
969 	return total;
970 }
971 
972 /**
973  * xe_ggtt_encode_pte_flags - Get PTE encoding flags for BO
974  * @ggtt: &xe_ggtt
975  * @bo: &xe_bo
976  * @pat_index: The pat_index for the PTE.
977  *
978  * This function returns the pte_flags for a given BO, without  address.
979  * It's used for DPT to fill a GGTT mapped BO with a linear lookup table.
980  */
981 u64 xe_ggtt_encode_pte_flags(struct xe_ggtt *ggtt,
982 			     struct xe_bo *bo, u16 pat_index)
983 {
984 	return ggtt->pt_ops->pte_encode_flags(bo, pat_index);
985 }
986 
987 /**
988  * xe_ggtt_read_pte - Read a PTE from the GGTT
989  * @ggtt: &xe_ggtt
990  * @offset: the offset for which the mapping should be read.
991  *
992  * Used by testcases, and by display reading out an inherited bios FB.
993  */
994 u64 xe_ggtt_read_pte(struct xe_ggtt *ggtt, u64 offset)
995 {
996 	return ioread64(ggtt->gsm + (offset / XE_PAGE_SIZE));
997 }
998