xref: /openbmc/linux/drivers/gpu/drm/i915/gt/intel_ppgtt.c (revision 7cffcade)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2020 Intel Corporation
4  */
5 
6 #include <linux/slab.h>
7 
8 #include "gem/i915_gem_lmem.h"
9 
10 #include "i915_trace.h"
11 #include "intel_gtt.h"
12 #include "gen6_ppgtt.h"
13 #include "gen8_ppgtt.h"
14 
15 struct i915_page_table *alloc_pt(struct i915_address_space *vm, int sz)
16 {
17 	struct i915_page_table *pt;
18 
19 	pt = kmalloc(sizeof(*pt), I915_GFP_ALLOW_FAIL);
20 	if (unlikely(!pt))
21 		return ERR_PTR(-ENOMEM);
22 
23 	pt->base = vm->alloc_pt_dma(vm, sz);
24 	if (IS_ERR(pt->base)) {
25 		kfree(pt);
26 		return ERR_PTR(-ENOMEM);
27 	}
28 
29 	pt->is_compact = false;
30 	atomic_set(&pt->used, 0);
31 	return pt;
32 }
33 
34 struct i915_page_directory *__alloc_pd(int count)
35 {
36 	struct i915_page_directory *pd;
37 
38 	pd = kzalloc(sizeof(*pd), I915_GFP_ALLOW_FAIL);
39 	if (unlikely(!pd))
40 		return NULL;
41 
42 	pd->entry = kcalloc(count, sizeof(*pd->entry), I915_GFP_ALLOW_FAIL);
43 	if (unlikely(!pd->entry)) {
44 		kfree(pd);
45 		return NULL;
46 	}
47 
48 	spin_lock_init(&pd->lock);
49 	return pd;
50 }
51 
52 struct i915_page_directory *alloc_pd(struct i915_address_space *vm)
53 {
54 	struct i915_page_directory *pd;
55 
56 	pd = __alloc_pd(I915_PDES);
57 	if (unlikely(!pd))
58 		return ERR_PTR(-ENOMEM);
59 
60 	pd->pt.base = vm->alloc_pt_dma(vm, I915_GTT_PAGE_SIZE_4K);
61 	if (IS_ERR(pd->pt.base)) {
62 		kfree(pd->entry);
63 		kfree(pd);
64 		return ERR_PTR(-ENOMEM);
65 	}
66 
67 	return pd;
68 }
69 
70 void free_px(struct i915_address_space *vm, struct i915_page_table *pt, int lvl)
71 {
72 	BUILD_BUG_ON(offsetof(struct i915_page_directory, pt));
73 
74 	if (lvl) {
75 		struct i915_page_directory *pd =
76 			container_of(pt, typeof(*pd), pt);
77 		kfree(pd->entry);
78 	}
79 
80 	if (pt->base)
81 		i915_gem_object_put(pt->base);
82 
83 	kfree(pt);
84 }
85 
86 static void
87 write_dma_entry(struct drm_i915_gem_object * const pdma,
88 		const unsigned short idx,
89 		const u64 encoded_entry)
90 {
91 	u64 * const vaddr = __px_vaddr(pdma);
92 
93 	vaddr[idx] = encoded_entry;
94 	drm_clflush_virt_range(&vaddr[idx], sizeof(u64));
95 }
96 
97 void
98 __set_pd_entry(struct i915_page_directory * const pd,
99 	       const unsigned short idx,
100 	       struct i915_page_table * const to,
101 	       u64 (*encode)(const dma_addr_t, const enum i915_cache_level))
102 {
103 	/* Each thread pre-pins the pd, and we may have a thread per pde. */
104 	GEM_BUG_ON(atomic_read(px_used(pd)) > NALLOC * I915_PDES);
105 
106 	atomic_inc(px_used(pd));
107 	pd->entry[idx] = to;
108 	write_dma_entry(px_base(pd), idx, encode(px_dma(to), I915_CACHE_LLC));
109 }
110 
111 void
112 clear_pd_entry(struct i915_page_directory * const pd,
113 	       const unsigned short idx,
114 	       const struct drm_i915_gem_object * const scratch)
115 {
116 	GEM_BUG_ON(atomic_read(px_used(pd)) == 0);
117 
118 	write_dma_entry(px_base(pd), idx, scratch->encode);
119 	pd->entry[idx] = NULL;
120 	atomic_dec(px_used(pd));
121 }
122 
123 bool
124 release_pd_entry(struct i915_page_directory * const pd,
125 		 const unsigned short idx,
126 		 struct i915_page_table * const pt,
127 		 const struct drm_i915_gem_object * const scratch)
128 {
129 	bool free = false;
130 
131 	if (atomic_add_unless(&pt->used, -1, 1))
132 		return false;
133 
134 	spin_lock(&pd->lock);
135 	if (atomic_dec_and_test(&pt->used)) {
136 		clear_pd_entry(pd, idx, scratch);
137 		free = true;
138 	}
139 	spin_unlock(&pd->lock);
140 
141 	return free;
142 }
143 
144 int i915_ppgtt_init_hw(struct intel_gt *gt)
145 {
146 	struct drm_i915_private *i915 = gt->i915;
147 
148 	gtt_write_workarounds(gt);
149 
150 	if (GRAPHICS_VER(i915) == 6)
151 		gen6_ppgtt_enable(gt);
152 	else if (GRAPHICS_VER(i915) == 7)
153 		gen7_ppgtt_enable(gt);
154 
155 	return 0;
156 }
157 
158 static struct i915_ppgtt *
159 __ppgtt_create(struct intel_gt *gt, unsigned long lmem_pt_obj_flags)
160 {
161 	if (GRAPHICS_VER(gt->i915) < 8)
162 		return gen6_ppgtt_create(gt);
163 	else
164 		return gen8_ppgtt_create(gt, lmem_pt_obj_flags);
165 }
166 
167 struct i915_ppgtt *i915_ppgtt_create(struct intel_gt *gt,
168 				     unsigned long lmem_pt_obj_flags)
169 {
170 	struct i915_ppgtt *ppgtt;
171 
172 	ppgtt = __ppgtt_create(gt, lmem_pt_obj_flags);
173 	if (IS_ERR(ppgtt))
174 		return ppgtt;
175 
176 	trace_i915_ppgtt_create(&ppgtt->vm);
177 
178 	return ppgtt;
179 }
180 
181 void ppgtt_bind_vma(struct i915_address_space *vm,
182 		    struct i915_vm_pt_stash *stash,
183 		    struct i915_vma_resource *vma_res,
184 		    enum i915_cache_level cache_level,
185 		    u32 flags)
186 {
187 	u32 pte_flags;
188 
189 	if (!vma_res->allocated) {
190 		vm->allocate_va_range(vm, stash, vma_res->start,
191 				      vma_res->vma_size);
192 		vma_res->allocated = true;
193 	}
194 
195 	/* Applicable to VLV, and gen8+ */
196 	pte_flags = 0;
197 	if (vma_res->bi.readonly)
198 		pte_flags |= PTE_READ_ONLY;
199 	if (vma_res->bi.lmem)
200 		pte_flags |= PTE_LM;
201 
202 	vm->insert_entries(vm, vma_res, cache_level, pte_flags);
203 	wmb();
204 }
205 
206 void ppgtt_unbind_vma(struct i915_address_space *vm,
207 		      struct i915_vma_resource *vma_res)
208 {
209 	if (!vma_res->allocated)
210 		return;
211 
212 	vm->clear_range(vm, vma_res->start, vma_res->vma_size);
213 	if (vma_res->tlb)
214 		vma_invalidate_tlb(vm, vma_res->tlb);
215 }
216 
217 static unsigned long pd_count(u64 size, int shift)
218 {
219 	/* Beware later misalignment */
220 	return (size + 2 * (BIT_ULL(shift) - 1)) >> shift;
221 }
222 
223 int i915_vm_alloc_pt_stash(struct i915_address_space *vm,
224 			   struct i915_vm_pt_stash *stash,
225 			   u64 size)
226 {
227 	unsigned long count;
228 	int shift, n, pt_sz;
229 
230 	shift = vm->pd_shift;
231 	if (!shift)
232 		return 0;
233 
234 	pt_sz = stash->pt_sz;
235 	if (!pt_sz)
236 		pt_sz = I915_GTT_PAGE_SIZE_4K;
237 	else
238 		GEM_BUG_ON(!IS_DGFX(vm->i915));
239 
240 	GEM_BUG_ON(!is_power_of_2(pt_sz));
241 
242 	count = pd_count(size, shift);
243 	while (count--) {
244 		struct i915_page_table *pt;
245 
246 		pt = alloc_pt(vm, pt_sz);
247 		if (IS_ERR(pt)) {
248 			i915_vm_free_pt_stash(vm, stash);
249 			return PTR_ERR(pt);
250 		}
251 
252 		pt->stash = stash->pt[0];
253 		stash->pt[0] = pt;
254 	}
255 
256 	for (n = 1; n < vm->top; n++) {
257 		shift += ilog2(I915_PDES); /* Each PD holds 512 entries */
258 		count = pd_count(size, shift);
259 		while (count--) {
260 			struct i915_page_directory *pd;
261 
262 			pd = alloc_pd(vm);
263 			if (IS_ERR(pd)) {
264 				i915_vm_free_pt_stash(vm, stash);
265 				return PTR_ERR(pd);
266 			}
267 
268 			pd->pt.stash = stash->pt[1];
269 			stash->pt[1] = &pd->pt;
270 		}
271 	}
272 
273 	return 0;
274 }
275 
276 int i915_vm_map_pt_stash(struct i915_address_space *vm,
277 			 struct i915_vm_pt_stash *stash)
278 {
279 	struct i915_page_table *pt;
280 	int n, err;
281 
282 	for (n = 0; n < ARRAY_SIZE(stash->pt); n++) {
283 		for (pt = stash->pt[n]; pt; pt = pt->stash) {
284 			err = map_pt_dma_locked(vm, pt->base);
285 			if (err)
286 				return err;
287 		}
288 	}
289 
290 	return 0;
291 }
292 
293 void i915_vm_free_pt_stash(struct i915_address_space *vm,
294 			   struct i915_vm_pt_stash *stash)
295 {
296 	struct i915_page_table *pt;
297 	int n;
298 
299 	for (n = 0; n < ARRAY_SIZE(stash->pt); n++) {
300 		while ((pt = stash->pt[n])) {
301 			stash->pt[n] = pt->stash;
302 			free_px(vm, pt, n);
303 		}
304 	}
305 }
306 
307 void ppgtt_init(struct i915_ppgtt *ppgtt, struct intel_gt *gt,
308 		unsigned long lmem_pt_obj_flags)
309 {
310 	struct drm_i915_private *i915 = gt->i915;
311 
312 	ppgtt->vm.gt = gt;
313 	ppgtt->vm.i915 = i915;
314 	ppgtt->vm.dma = i915->drm.dev;
315 	ppgtt->vm.total = BIT_ULL(RUNTIME_INFO(i915)->ppgtt_size);
316 	ppgtt->vm.lmem_pt_obj_flags = lmem_pt_obj_flags;
317 
318 	dma_resv_init(&ppgtt->vm._resv);
319 	i915_address_space_init(&ppgtt->vm, VM_CLASS_PPGTT);
320 
321 	ppgtt->vm.vma_ops.bind_vma    = ppgtt_bind_vma;
322 	ppgtt->vm.vma_ops.unbind_vma  = ppgtt_unbind_vma;
323 }
324