2 * Copyright © 2008-2012 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
24 * Eric Anholt <eric@anholt.net>
25 * Chris Wilson <chris@chris-wilson.co.uk>
30 #include <drm/i915_drm.h>
34 * The BIOS typically reserves some of the system's memory for the exclusive
35 * use of the integrated graphics. This memory is no longer available for
36 * use by the OS and so the user finds that his system has less memory
37 * available than he put in. We refer to this memory as stolen.
39 * The BIOS will allocate its framebuffer from the stolen memory. Our
40 * goal is try to reuse that object for our own fbcon which must always
41 * be available for panics. Anything else we can reuse the stolen memory
45 static unsigned long i915_stolen_to_physical(struct drm_device *dev)
47 struct drm_i915_private *dev_priv = dev->dev_private;
51 /* Almost universally we can find the Graphics Base of Stolen Memory
52 * at offset 0x5c in the igfx configuration space. On a few (desktop)
53 * machines this is also mirrored in the bridge device at different
54 * locations, or in the MCHBAR. On gen2, the layout is again slightly
55 * different with the Graphics Segment immediately following Top of
56 * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
57 * reported by 865g, so we just use the top of memory as determined
60 * XXX However gen2 requires an unavailable symbol.
63 if (INTEL_INFO(dev)->gen >= 3) {
64 /* Read Graphics Base of Stolen Memory directly */
65 pci_read_config_dword(dev->pdev, 0x5c, &base);
66 base &= ~((1<<20) - 1);
69 /* Stolen is immediately above Top of Memory */
70 base = max_low_pfn_mapped << PAGE_SHIFT;
77 /* Verify that nothing else uses this physical address. Stolen
78 * memory should be reserved by the BIOS and hidden from the
79 * kernel. So if the region is already marked as busy, something
82 r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
83 "Graphics Stolen Memory");
85 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
86 base, base + (uint32_t)dev_priv->gtt.stolen_size);
93 static int i915_setup_compression(struct drm_device *dev, int size)
95 struct drm_i915_private *dev_priv = dev->dev_private;
96 struct drm_mm_node *compressed_fb, *uninitialized_var(compressed_llb);
98 /* Try to over-allocate to reduce reallocations and fragmentation */
99 compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,
100 size <<= 1, 4096, 0);
102 compressed_fb = drm_mm_search_free(&dev_priv->mm.stolen,
103 size >>= 1, 4096, 0);
105 compressed_fb = drm_mm_get_block(compressed_fb, size, 4096);
109 if (HAS_PCH_SPLIT(dev))
110 I915_WRITE(ILK_DPFC_CB_BASE, compressed_fb->start);
111 else if (IS_GM45(dev)) {
112 I915_WRITE(DPFC_CB_BASE, compressed_fb->start);
114 compressed_llb = drm_mm_search_free(&dev_priv->mm.stolen,
117 compressed_llb = drm_mm_get_block(compressed_llb,
122 dev_priv->fbc.compressed_llb = compressed_llb;
124 I915_WRITE(FBC_CFB_BASE,
125 dev_priv->mm.stolen_base + compressed_fb->start);
126 I915_WRITE(FBC_LL_BASE,
127 dev_priv->mm.stolen_base + compressed_llb->start);
130 dev_priv->fbc.compressed_fb = compressed_fb;
131 dev_priv->fbc.size = size;
133 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
139 drm_mm_put_block(compressed_fb);
141 pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
145 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size)
147 struct drm_i915_private *dev_priv = dev->dev_private;
149 if (!drm_mm_initialized(&dev_priv->mm.stolen))
152 if (size < dev_priv->fbc.size)
155 /* Release any current block */
156 i915_gem_stolen_cleanup_compression(dev);
158 return i915_setup_compression(dev, size);
161 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
163 struct drm_i915_private *dev_priv = dev->dev_private;
165 if (dev_priv->fbc.size == 0)
168 if (dev_priv->fbc.compressed_fb)
169 drm_mm_put_block(dev_priv->fbc.compressed_fb);
171 if (dev_priv->fbc.compressed_llb)
172 drm_mm_put_block(dev_priv->fbc.compressed_llb);
174 dev_priv->fbc.size = 0;
177 void i915_gem_cleanup_stolen(struct drm_device *dev)
179 struct drm_i915_private *dev_priv = dev->dev_private;
181 if (!drm_mm_initialized(&dev_priv->mm.stolen))
184 i915_gem_stolen_cleanup_compression(dev);
185 drm_mm_takedown(&dev_priv->mm.stolen);
188 int i915_gem_init_stolen(struct drm_device *dev)
190 struct drm_i915_private *dev_priv = dev->dev_private;
191 int bios_reserved = 0;
193 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
194 if (dev_priv->mm.stolen_base == 0)
197 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
198 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
200 if (IS_VALLEYVIEW(dev))
201 bios_reserved = 1024*1024; /* top 1M on VLV/BYT */
203 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
206 /* Basic memrange allocator for stolen space */
207 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
213 static struct sg_table *
214 i915_pages_create_for_stolen(struct drm_device *dev,
215 u32 offset, u32 size)
217 struct drm_i915_private *dev_priv = dev->dev_private;
219 struct scatterlist *sg;
221 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
222 BUG_ON(offset > dev_priv->gtt.stolen_size - size);
224 /* We hide that we have no struct page backing our stolen object
225 * by wrapping the contiguous physical allocation with a fake
226 * dma mapping in a single scatterlist.
229 st = kmalloc(sizeof(*st), GFP_KERNEL);
233 if (sg_alloc_table(st, 1, GFP_KERNEL)) {
242 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
243 sg_dma_len(sg) = size;
248 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
254 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
256 /* Should only be called during free */
257 sg_free_table(obj->pages);
261 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
262 .get_pages = i915_gem_object_get_pages_stolen,
263 .put_pages = i915_gem_object_put_pages_stolen,
266 static struct drm_i915_gem_object *
267 _i915_gem_object_create_stolen(struct drm_device *dev,
268 struct drm_mm_node *stolen)
270 struct drm_i915_gem_object *obj;
272 obj = i915_gem_object_alloc(dev);
276 if (drm_gem_private_object_init(dev, &obj->base, stolen->size))
279 i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
281 obj->pages = i915_pages_create_for_stolen(dev,
282 stolen->start, stolen->size);
283 if (obj->pages == NULL)
286 obj->has_dma_mapping = true;
287 i915_gem_object_pin_pages(obj);
288 obj->stolen = stolen;
290 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
291 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
296 i915_gem_object_free(obj);
300 struct drm_i915_gem_object *
301 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
303 struct drm_i915_private *dev_priv = dev->dev_private;
304 struct drm_i915_gem_object *obj;
305 struct drm_mm_node *stolen;
307 if (!drm_mm_initialized(&dev_priv->mm.stolen))
310 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
314 stolen = drm_mm_search_free(&dev_priv->mm.stolen, size, 4096, 0);
316 stolen = drm_mm_get_block(stolen, size, 4096);
320 obj = _i915_gem_object_create_stolen(dev, stolen);
324 drm_mm_put_block(stolen);
328 struct drm_i915_gem_object *
329 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
334 struct drm_i915_private *dev_priv = dev->dev_private;
335 struct i915_address_space *ggtt = &dev_priv->gtt.base;
336 struct drm_i915_gem_object *obj;
337 struct drm_mm_node *stolen;
338 struct i915_vma *vma;
341 if (!drm_mm_initialized(&dev_priv->mm.stolen))
344 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
345 stolen_offset, gtt_offset, size);
347 /* KISS and expect everything to be page-aligned */
348 BUG_ON(stolen_offset & 4095);
351 if (WARN_ON(size == 0))
354 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
358 stolen->start = stolen_offset;
360 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
362 DRM_DEBUG_KMS("failed to allocate stolen space\n");
367 obj = _i915_gem_object_create_stolen(dev, stolen);
369 DRM_DEBUG_KMS("failed to allocate stolen object\n");
370 drm_mm_put_block(stolen);
374 /* Some objects just need physical mem from stolen space */
375 if (gtt_offset == I915_GTT_OFFSET_NONE)
378 vma = i915_gem_vma_create(obj, ggtt);
384 /* To simplify the initialisation sequence between KMS and GTT,
385 * we allow construction of the stolen object prior to
386 * setting up the GTT space. The actual reservation will occur
389 vma->node.start = gtt_offset;
390 vma->node.size = size;
391 if (drm_mm_initialized(&ggtt->mm)) {
392 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
394 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
399 obj->has_global_gtt_mapping = 1;
401 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
402 list_add_tail(&vma->mm_list, &ggtt->inactive_list);
407 i915_gem_vma_destroy(vma);
409 drm_mm_put_block(stolen);
410 drm_gem_object_unreference(&obj->base);
415 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
418 drm_mm_put_block(obj->stolen);