xref: /linux/drivers/gpu/drm/xe/xe_ggtt.c (revision 2b0cfa6e49566c8fa6759734cf821aa6e8271a9e)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2021 Intel Corporation
4  */
5 
6 #include "xe_ggtt.h"
7 
8 #include <linux/sizes.h>
9 
10 #include <drm/drm_managed.h>
11 #include <drm/i915_drm.h>
12 
13 #include "regs/xe_gt_regs.h"
14 #include "xe_bo.h"
15 #include "xe_device.h"
16 #include "xe_gt.h"
17 #include "xe_gt_tlb_invalidation.h"
18 #include "xe_map.h"
19 #include "xe_mmio.h"
20 #include "xe_wopcm.h"
21 
22 #define XELPG_GGTT_PTE_PAT0	BIT_ULL(52)
23 #define XELPG_GGTT_PTE_PAT1	BIT_ULL(53)
24 
25 /* GuC addresses above GUC_GGTT_TOP also don't map through the GTT */
26 #define GUC_GGTT_TOP	0xFEE00000
27 
28 static u64 xelp_ggtt_pte_encode_bo(struct xe_bo *bo, u64 bo_offset,
29 				   u16 pat_index)
30 {
31 	u64 pte;
32 
33 	pte = xe_bo_addr(bo, bo_offset, XE_PAGE_SIZE);
34 	pte |= XE_PAGE_PRESENT;
35 
36 	if (xe_bo_is_vram(bo) || xe_bo_is_stolen_devmem(bo))
37 		pte |= XE_GGTT_PTE_DM;
38 
39 	return pte;
40 }
41 
42 static u64 xelpg_ggtt_pte_encode_bo(struct xe_bo *bo, u64 bo_offset,
43 				    u16 pat_index)
44 {
45 	struct xe_device *xe = xe_bo_device(bo);
46 	u64 pte;
47 
48 	pte = xelp_ggtt_pte_encode_bo(bo, bo_offset, pat_index);
49 
50 	xe_assert(xe, pat_index <= 3);
51 
52 	if (pat_index & BIT(0))
53 		pte |= XELPG_GGTT_PTE_PAT0;
54 
55 	if (pat_index & BIT(1))
56 		pte |= XELPG_GGTT_PTE_PAT1;
57 
58 	return pte;
59 }
60 
61 static unsigned int probe_gsm_size(struct pci_dev *pdev)
62 {
63 	u16 gmch_ctl, ggms;
64 
65 	pci_read_config_word(pdev, SNB_GMCH_CTRL, &gmch_ctl);
66 	ggms = (gmch_ctl >> BDW_GMCH_GGMS_SHIFT) & BDW_GMCH_GGMS_MASK;
67 	return ggms ? SZ_1M << ggms : 0;
68 }
69 
70 void xe_ggtt_set_pte(struct xe_ggtt *ggtt, u64 addr, u64 pte)
71 {
72 	xe_tile_assert(ggtt->tile, !(addr & XE_PTE_MASK));
73 	xe_tile_assert(ggtt->tile, addr < ggtt->size);
74 
75 	writeq(pte, &ggtt->gsm[addr >> XE_PTE_SHIFT]);
76 }
77 
78 static void xe_ggtt_clear(struct xe_ggtt *ggtt, u64 start, u64 size)
79 {
80 	u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[XE_CACHE_WB];
81 	u64 end = start + size - 1;
82 	u64 scratch_pte;
83 
84 	xe_tile_assert(ggtt->tile, start < end);
85 
86 	if (ggtt->scratch)
87 		scratch_pte = ggtt->pt_ops->pte_encode_bo(ggtt->scratch, 0,
88 							  pat_index);
89 	else
90 		scratch_pte = 0;
91 
92 	while (start < end) {
93 		xe_ggtt_set_pte(ggtt, start, scratch_pte);
94 		start += XE_PAGE_SIZE;
95 	}
96 }
97 
98 static void ggtt_fini_early(struct drm_device *drm, void *arg)
99 {
100 	struct xe_ggtt *ggtt = arg;
101 
102 	mutex_destroy(&ggtt->lock);
103 	drm_mm_takedown(&ggtt->mm);
104 }
105 
106 static void ggtt_fini(struct drm_device *drm, void *arg)
107 {
108 	struct xe_ggtt *ggtt = arg;
109 
110 	ggtt->scratch = NULL;
111 }
112 
113 static void primelockdep(struct xe_ggtt *ggtt)
114 {
115 	if (!IS_ENABLED(CONFIG_LOCKDEP))
116 		return;
117 
118 	fs_reclaim_acquire(GFP_KERNEL);
119 	might_lock(&ggtt->lock);
120 	fs_reclaim_release(GFP_KERNEL);
121 }
122 
123 static const struct xe_ggtt_pt_ops xelp_pt_ops = {
124 	.pte_encode_bo = xelp_ggtt_pte_encode_bo,
125 };
126 
127 static const struct xe_ggtt_pt_ops xelpg_pt_ops = {
128 	.pte_encode_bo = xelpg_ggtt_pte_encode_bo,
129 };
130 
131 /*
132  * Early GGTT initialization, which allows to create new mappings usable by the
133  * GuC.
134  * Mappings are not usable by the HW engines, as it doesn't have scratch /
135  * initial clear done to it yet. That will happen in the regular, non-early
136  * GGTT init.
137  */
138 int xe_ggtt_init_early(struct xe_ggtt *ggtt)
139 {
140 	struct xe_device *xe = tile_to_xe(ggtt->tile);
141 	struct pci_dev *pdev = to_pci_dev(xe->drm.dev);
142 	unsigned int gsm_size;
143 
144 	gsm_size = probe_gsm_size(pdev);
145 	if (gsm_size == 0) {
146 		drm_err(&xe->drm, "Hardware reported no preallocated GSM\n");
147 		return -ENOMEM;
148 	}
149 
150 	ggtt->gsm = ggtt->tile->mmio.regs + SZ_8M;
151 	ggtt->size = (gsm_size / 8) * (u64) XE_PAGE_SIZE;
152 
153 	if (IS_DGFX(xe) && xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K)
154 		ggtt->flags |= XE_GGTT_FLAGS_64K;
155 
156 	/*
157 	 * 8B per entry, each points to a 4KB page.
158 	 *
159 	 * The GuC address space is limited on both ends of the GGTT, because
160 	 * the GuC shim HW redirects accesses to those addresses to other HW
161 	 * areas instead of going through the GGTT. On the bottom end, the GuC
162 	 * can't access offsets below the WOPCM size, while on the top side the
163 	 * limit is fixed at GUC_GGTT_TOP. To keep things simple, instead of
164 	 * checking each object to see if they are accessed by GuC or not, we
165 	 * just exclude those areas from the allocator. Additionally, to
166 	 * simplify the driver load, we use the maximum WOPCM size in this logic
167 	 * instead of the programmed one, so we don't need to wait until the
168 	 * actual size to be programmed is determined (which requires FW fetch)
169 	 * before initializing the GGTT. These simplifications might waste space
170 	 * in the GGTT (about 20-25 MBs depending on the platform) but we can
171 	 * live with this.
172 	 *
173 	 * Another benifit of this is the GuC bootrom can't access anything
174 	 * below the WOPCM max size so anything the bootom needs to access (e.g.
175 	 * a RSA key) needs to be placed in the GGTT above the WOPCM max size.
176 	 * Starting the GGTT allocations above the WOPCM max give us the correct
177 	 * placement for free.
178 	 */
179 	if (ggtt->size > GUC_GGTT_TOP)
180 		ggtt->size = GUC_GGTT_TOP;
181 
182 	if (GRAPHICS_VERx100(xe) >= 1270)
183 		ggtt->pt_ops = &xelpg_pt_ops;
184 	else
185 		ggtt->pt_ops = &xelp_pt_ops;
186 
187 	drm_mm_init(&ggtt->mm, xe_wopcm_size(xe),
188 		    ggtt->size - xe_wopcm_size(xe));
189 	mutex_init(&ggtt->lock);
190 	primelockdep(ggtt);
191 
192 	return drmm_add_action_or_reset(&xe->drm, ggtt_fini_early, ggtt);
193 }
194 
195 static void xe_ggtt_initial_clear(struct xe_ggtt *ggtt)
196 {
197 	struct drm_mm_node *hole;
198 	u64 start, end;
199 
200 	/* Display may have allocated inside ggtt, so be careful with clearing here */
201 	xe_device_mem_access_get(tile_to_xe(ggtt->tile));
202 	mutex_lock(&ggtt->lock);
203 	drm_mm_for_each_hole(hole, &ggtt->mm, start, end)
204 		xe_ggtt_clear(ggtt, start, end - start);
205 
206 	xe_ggtt_invalidate(ggtt);
207 	mutex_unlock(&ggtt->lock);
208 	xe_device_mem_access_put(tile_to_xe(ggtt->tile));
209 }
210 
211 int xe_ggtt_init(struct xe_ggtt *ggtt)
212 {
213 	struct xe_device *xe = tile_to_xe(ggtt->tile);
214 	unsigned int flags;
215 	int err;
216 
217 	/*
218 	 * So we don't need to worry about 64K GGTT layout when dealing with
219 	 * scratch entires, rather keep the scratch page in system memory on
220 	 * platforms where 64K pages are needed for VRAM.
221 	 */
222 	flags = XE_BO_CREATE_PINNED_BIT;
223 	if (ggtt->flags & XE_GGTT_FLAGS_64K)
224 		flags |= XE_BO_CREATE_SYSTEM_BIT;
225 	else
226 		flags |= XE_BO_CREATE_VRAM_IF_DGFX(ggtt->tile);
227 
228 	ggtt->scratch = xe_managed_bo_create_pin_map(xe, ggtt->tile, XE_PAGE_SIZE, flags);
229 	if (IS_ERR(ggtt->scratch)) {
230 		err = PTR_ERR(ggtt->scratch);
231 		goto err;
232 	}
233 
234 	xe_map_memset(xe, &ggtt->scratch->vmap, 0, 0, ggtt->scratch->size);
235 
236 	xe_ggtt_initial_clear(ggtt);
237 
238 	return drmm_add_action_or_reset(&xe->drm, ggtt_fini, ggtt);
239 err:
240 	ggtt->scratch = NULL;
241 	return err;
242 }
243 
244 #define GUC_TLB_INV_CR				XE_REG(0xcee8)
245 #define   GUC_TLB_INV_CR_INVALIDATE		REG_BIT(0)
246 #define PVC_GUC_TLB_INV_DESC0			XE_REG(0xcf7c)
247 #define   PVC_GUC_TLB_INV_DESC0_VALID		REG_BIT(0)
248 #define PVC_GUC_TLB_INV_DESC1			XE_REG(0xcf80)
249 #define   PVC_GUC_TLB_INV_DESC1_INVALIDATE	REG_BIT(6)
250 
251 static void ggtt_invalidate_gt_tlb(struct xe_gt *gt)
252 {
253 	if (!gt)
254 		return;
255 
256 	/*
257 	 * Invalidation can happen when there's no in-flight work keeping the
258 	 * GT awake.  We need to explicitly grab forcewake to ensure the GT
259 	 * and GuC are accessible.
260 	 */
261 	xe_force_wake_get(gt_to_fw(gt), XE_FW_GT);
262 
263 	/* TODO: vfunc for GuC vs. non-GuC */
264 
265 	if (gt->uc.guc.submission_state.enabled) {
266 		int seqno;
267 
268 		seqno = xe_gt_tlb_invalidation_guc(gt);
269 		xe_gt_assert(gt, seqno > 0);
270 		if (seqno > 0)
271 			xe_gt_tlb_invalidation_wait(gt, seqno);
272 	} else if (xe_device_uc_enabled(gt_to_xe(gt))) {
273 		struct xe_device *xe = gt_to_xe(gt);
274 
275 		if (xe->info.platform == XE_PVC || GRAPHICS_VER(xe) >= 20) {
276 			xe_mmio_write32(gt, PVC_GUC_TLB_INV_DESC1,
277 					PVC_GUC_TLB_INV_DESC1_INVALIDATE);
278 			xe_mmio_write32(gt, PVC_GUC_TLB_INV_DESC0,
279 					PVC_GUC_TLB_INV_DESC0_VALID);
280 		} else
281 			xe_mmio_write32(gt, GUC_TLB_INV_CR,
282 					GUC_TLB_INV_CR_INVALIDATE);
283 	}
284 
285 	xe_force_wake_put(gt_to_fw(gt), XE_FW_GT);
286 }
287 
288 void xe_ggtt_invalidate(struct xe_ggtt *ggtt)
289 {
290 	/* Each GT in a tile has its own TLB to cache GGTT lookups */
291 	ggtt_invalidate_gt_tlb(ggtt->tile->primary_gt);
292 	ggtt_invalidate_gt_tlb(ggtt->tile->media_gt);
293 }
294 
295 void xe_ggtt_printk(struct xe_ggtt *ggtt, const char *prefix)
296 {
297 	u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[XE_CACHE_WB];
298 	u64 addr, scratch_pte;
299 
300 	scratch_pte = ggtt->pt_ops->pte_encode_bo(ggtt->scratch, 0, pat_index);
301 
302 	printk("%sGlobal GTT:", prefix);
303 	for (addr = 0; addr < ggtt->size; addr += XE_PAGE_SIZE) {
304 		unsigned int i = addr / XE_PAGE_SIZE;
305 
306 		xe_tile_assert(ggtt->tile, addr <= U32_MAX);
307 		if (ggtt->gsm[i] == scratch_pte)
308 			continue;
309 
310 		printk("%s    ggtt[0x%08x] = 0x%016llx",
311 		       prefix, (u32)addr, ggtt->gsm[i]);
312 	}
313 }
314 
315 int xe_ggtt_insert_special_node_locked(struct xe_ggtt *ggtt, struct drm_mm_node *node,
316 				       u32 size, u32 align, u32 mm_flags)
317 {
318 	return drm_mm_insert_node_generic(&ggtt->mm, node, size, align, 0,
319 					  mm_flags);
320 }
321 
322 int xe_ggtt_insert_special_node(struct xe_ggtt *ggtt, struct drm_mm_node *node,
323 				u32 size, u32 align)
324 {
325 	int ret;
326 
327 	mutex_lock(&ggtt->lock);
328 	ret = xe_ggtt_insert_special_node_locked(ggtt, node, size,
329 						 align, DRM_MM_INSERT_HIGH);
330 	mutex_unlock(&ggtt->lock);
331 
332 	return ret;
333 }
334 
335 void xe_ggtt_map_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)
336 {
337 	u16 pat_index = tile_to_xe(ggtt->tile)->pat.idx[XE_CACHE_WB];
338 	u64 start = bo->ggtt_node.start;
339 	u64 offset, pte;
340 
341 	for (offset = 0; offset < bo->size; offset += XE_PAGE_SIZE) {
342 		pte = ggtt->pt_ops->pte_encode_bo(bo, offset, pat_index);
343 		xe_ggtt_set_pte(ggtt, start + offset, pte);
344 	}
345 
346 	xe_ggtt_invalidate(ggtt);
347 }
348 
349 static int __xe_ggtt_insert_bo_at(struct xe_ggtt *ggtt, struct xe_bo *bo,
350 				  u64 start, u64 end)
351 {
352 	int err;
353 	u64 alignment = XE_PAGE_SIZE;
354 
355 	if (xe_bo_is_vram(bo) && ggtt->flags & XE_GGTT_FLAGS_64K)
356 		alignment = SZ_64K;
357 
358 	if (XE_WARN_ON(bo->ggtt_node.size)) {
359 		/* Someone's already inserted this BO in the GGTT */
360 		xe_tile_assert(ggtt->tile, bo->ggtt_node.size == bo->size);
361 		return 0;
362 	}
363 
364 	err = xe_bo_validate(bo, NULL, false);
365 	if (err)
366 		return err;
367 
368 	xe_device_mem_access_get(tile_to_xe(ggtt->tile));
369 	mutex_lock(&ggtt->lock);
370 	err = drm_mm_insert_node_in_range(&ggtt->mm, &bo->ggtt_node, bo->size,
371 					  alignment, 0, start, end, 0);
372 	if (!err)
373 		xe_ggtt_map_bo(ggtt, bo);
374 	mutex_unlock(&ggtt->lock);
375 	xe_device_mem_access_put(tile_to_xe(ggtt->tile));
376 
377 	return err;
378 }
379 
380 int xe_ggtt_insert_bo_at(struct xe_ggtt *ggtt, struct xe_bo *bo,
381 			 u64 start, u64 end)
382 {
383 	return __xe_ggtt_insert_bo_at(ggtt, bo, start, end);
384 }
385 
386 int xe_ggtt_insert_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)
387 {
388 	return __xe_ggtt_insert_bo_at(ggtt, bo, 0, U64_MAX);
389 }
390 
391 void xe_ggtt_remove_node(struct xe_ggtt *ggtt, struct drm_mm_node *node)
392 {
393 	xe_device_mem_access_get(tile_to_xe(ggtt->tile));
394 	mutex_lock(&ggtt->lock);
395 
396 	xe_ggtt_clear(ggtt, node->start, node->size);
397 	drm_mm_remove_node(node);
398 	node->size = 0;
399 
400 	xe_ggtt_invalidate(ggtt);
401 
402 	mutex_unlock(&ggtt->lock);
403 	xe_device_mem_access_put(tile_to_xe(ggtt->tile));
404 }
405 
406 void xe_ggtt_remove_bo(struct xe_ggtt *ggtt, struct xe_bo *bo)
407 {
408 	if (XE_WARN_ON(!bo->ggtt_node.size))
409 		return;
410 
411 	/* This BO is not currently in the GGTT */
412 	xe_tile_assert(ggtt->tile, bo->ggtt_node.size == bo->size);
413 
414 	xe_ggtt_remove_node(ggtt, &bo->ggtt_node);
415 }
416 
417 int xe_ggtt_dump(struct xe_ggtt *ggtt, struct drm_printer *p)
418 {
419 	int err;
420 
421 	err = mutex_lock_interruptible(&ggtt->lock);
422 	if (err)
423 		return err;
424 
425 	drm_mm_print(&ggtt->mm, p);
426 	mutex_unlock(&ggtt->lock);
427 	return err;
428 }
429