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_gt.h"
12 #include "intel_gtt.h"
13 #include "gen6_ppgtt.h"
14 #include "gen8_ppgtt.h"
15 
alloc_pt(struct i915_address_space * vm,int sz)16 struct i915_page_table *alloc_pt(struct i915_address_space *vm, int sz)
17 {
18 	struct i915_page_table *pt;
19 
20 	pt = kmalloc(sizeof(*pt), I915_GFP_ALLOW_FAIL);
21 	if (unlikely(!pt))
22 		return ERR_PTR(-ENOMEM);
23 
24 	pt->base = vm->alloc_pt_dma(vm, sz);
25 	if (IS_ERR(pt->base)) {
26 		kfree(pt);
27 		return ERR_PTR(-ENOMEM);
28 	}
29 
30 	pt->is_compact = false;
31 	atomic_set(&pt->used, 0);
32 	return pt;
33 }
34 
__alloc_pd(int count)35 struct i915_page_directory *__alloc_pd(int count)
36 {
37 	struct i915_page_directory *pd;
38 
39 	pd = kzalloc(sizeof(*pd), I915_GFP_ALLOW_FAIL);
40 	if (unlikely(!pd))
41 		return NULL;
42 
43 	pd->entry = kcalloc(count, sizeof(*pd->entry), I915_GFP_ALLOW_FAIL);
44 	if (unlikely(!pd->entry)) {
45 		kfree(pd);
46 		return NULL;
47 	}
48 
49 	spin_lock_init(&pd->lock);
50 	return pd;
51 }
52 
alloc_pd(struct i915_address_space * vm)53 struct i915_page_directory *alloc_pd(struct i915_address_space *vm)
54 {
55 	struct i915_page_directory *pd;
56 
57 	pd = __alloc_pd(I915_PDES);
58 	if (unlikely(!pd))
59 		return ERR_PTR(-ENOMEM);
60 
61 	pd->pt.base = vm->alloc_pt_dma(vm, I915_GTT_PAGE_SIZE_4K);
62 	if (IS_ERR(pd->pt.base)) {
63 		kfree(pd->entry);
64 		kfree(pd);
65 		return ERR_PTR(-ENOMEM);
66 	}
67 
68 	return pd;
69 }
70 
free_px(struct i915_address_space * vm,struct i915_page_table * pt,int lvl)71 void free_px(struct i915_address_space *vm, struct i915_page_table *pt, int lvl)
72 {
73 	BUILD_BUG_ON(offsetof(struct i915_page_directory, pt));
74 
75 	if (lvl) {
76 		struct i915_page_directory *pd =
77 			container_of(pt, typeof(*pd), pt);
78 		kfree(pd->entry);
79 	}
80 
81 	if (pt->base)
82 		i915_gem_object_put(pt->base);
83 
84 	kfree(pt);
85 }
86 
87 static void
write_dma_entry(struct drm_i915_gem_object * const pdma,const unsigned short idx,const u64 encoded_entry)88 write_dma_entry(struct drm_i915_gem_object * const pdma,
89 		const unsigned short idx,
90 		const u64 encoded_entry)
91 {
92 	u64 * const vaddr = __px_vaddr(pdma);
93 
94 	vaddr[idx] = encoded_entry;
95 	drm_clflush_virt_range(&vaddr[idx], sizeof(u64));
96 }
97 
98 void
__set_pd_entry(struct i915_page_directory * const pd,const unsigned short idx,struct i915_page_table * const to,u64 (* encode)(const dma_addr_t,const enum i915_cache_level))99 __set_pd_entry(struct i915_page_directory * const pd,
100 	       const unsigned short idx,
101 	       struct i915_page_table * const to,
102 	       u64 (*encode)(const dma_addr_t, const enum i915_cache_level))
103 {
104 	/* Each thread pre-pins the pd, and we may have a thread per pde. */
105 	GEM_BUG_ON(atomic_read(px_used(pd)) > NALLOC * I915_PDES);
106 
107 	atomic_inc(px_used(pd));
108 	pd->entry[idx] = to;
109 	write_dma_entry(px_base(pd), idx, encode(px_dma(to), I915_CACHE_LLC));
110 }
111 
112 void
clear_pd_entry(struct i915_page_directory * const pd,const unsigned short idx,const struct drm_i915_gem_object * const scratch)113 clear_pd_entry(struct i915_page_directory * const pd,
114 	       const unsigned short idx,
115 	       const struct drm_i915_gem_object * const scratch)
116 {
117 	GEM_BUG_ON(atomic_read(px_used(pd)) == 0);
118 
119 	write_dma_entry(px_base(pd), idx, scratch->encode);
120 	pd->entry[idx] = NULL;
121 	atomic_dec(px_used(pd));
122 }
123 
124 bool
release_pd_entry(struct i915_page_directory * const pd,const unsigned short idx,struct i915_page_table * const pt,const struct drm_i915_gem_object * const scratch)125 release_pd_entry(struct i915_page_directory * const pd,
126 		 const unsigned short idx,
127 		 struct i915_page_table * const pt,
128 		 const struct drm_i915_gem_object * const scratch)
129 {
130 	bool free = false;
131 
132 	if (atomic_add_unless(&pt->used, -1, 1))
133 		return false;
134 
135 	spin_lock(&pd->lock);
136 	if (atomic_dec_and_test(&pt->used)) {
137 		clear_pd_entry(pd, idx, scratch);
138 		free = true;
139 	}
140 	spin_unlock(&pd->lock);
141 
142 	return free;
143 }
144 
i915_ppgtt_init_hw(struct intel_gt * gt)145 int i915_ppgtt_init_hw(struct intel_gt *gt)
146 {
147 	struct drm_i915_private *i915 = gt->i915;
148 
149 	gtt_write_workarounds(gt);
150 
151 	if (GRAPHICS_VER(i915) == 6)
152 		gen6_ppgtt_enable(gt);
153 	else if (GRAPHICS_VER(i915) == 7)
154 		gen7_ppgtt_enable(gt);
155 
156 	return 0;
157 }
158 
159 static struct i915_ppgtt *
__ppgtt_create(struct intel_gt * gt,unsigned long lmem_pt_obj_flags)160 __ppgtt_create(struct intel_gt *gt, unsigned long lmem_pt_obj_flags)
161 {
162 	if (GRAPHICS_VER(gt->i915) < 8)
163 		return gen6_ppgtt_create(gt);
164 	else
165 		return gen8_ppgtt_create(gt, lmem_pt_obj_flags);
166 }
167 
i915_ppgtt_create(struct intel_gt * gt,unsigned long lmem_pt_obj_flags)168 struct i915_ppgtt *i915_ppgtt_create(struct intel_gt *gt,
169 				     unsigned long lmem_pt_obj_flags)
170 {
171 	struct i915_ppgtt *ppgtt;
172 
173 	ppgtt = __ppgtt_create(gt, lmem_pt_obj_flags);
174 	if (IS_ERR(ppgtt))
175 		return ppgtt;
176 
177 	trace_i915_ppgtt_create(&ppgtt->vm);
178 
179 	return ppgtt;
180 }
181 
ppgtt_bind_vma(struct i915_address_space * vm,struct i915_vm_pt_stash * stash,struct i915_vma_resource * vma_res,unsigned int pat_index,u32 flags)182 void ppgtt_bind_vma(struct i915_address_space *vm,
183 		    struct i915_vm_pt_stash *stash,
184 		    struct i915_vma_resource *vma_res,
185 		    unsigned int pat_index,
186 		    u32 flags)
187 {
188 	u32 pte_flags;
189 
190 	if (!vma_res->allocated) {
191 		vm->allocate_va_range(vm, stash, vma_res->start,
192 				      vma_res->vma_size);
193 		vma_res->allocated = true;
194 	}
195 
196 	/* Applicable to VLV, and gen8+ */
197 	pte_flags = 0;
198 	if (vma_res->bi.readonly)
199 		pte_flags |= PTE_READ_ONLY;
200 	if (vma_res->bi.lmem)
201 		pte_flags |= PTE_LM;
202 
203 	vm->insert_entries(vm, vma_res, pat_index, pte_flags);
204 	wmb();
205 }
206 
ppgtt_unbind_vma(struct i915_address_space * vm,struct i915_vma_resource * vma_res)207 void ppgtt_unbind_vma(struct i915_address_space *vm,
208 		      struct i915_vma_resource *vma_res)
209 {
210 	if (!vma_res->allocated)
211 		return;
212 
213 	vm->clear_range(vm, vma_res->start, vma_res->vma_size);
214 	vma_invalidate_tlb(vm, vma_res->tlb);
215 }
216 
pd_count(u64 size,int shift)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 
i915_vm_alloc_pt_stash(struct i915_address_space * vm,struct i915_vm_pt_stash * stash,u64 size)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 
i915_vm_map_pt_stash(struct i915_address_space * vm,struct i915_vm_pt_stash * stash)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 
i915_vm_free_pt_stash(struct i915_address_space * vm,struct i915_vm_pt_stash * stash)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 
ppgtt_init(struct i915_ppgtt * ppgtt,struct intel_gt * gt,unsigned long lmem_pt_obj_flags)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