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;
50 /* Almost universally we can find the Graphics Base of Stolen Memory
51 * at offset 0x5c in the igfx configuration space. On a few (desktop)
52 * machines this is also mirrored in the bridge device at different
53 * locations, or in the MCHBAR. On gen2, the layout is again slightly
54 * different with the Graphics Segment immediately following Top of
55 * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
56 * reported by 865g, so we just use the top of memory as determined
59 * XXX However gen2 requires an unavailable symbol.
62 if (INTEL_INFO(dev)->gen >= 3) {
63 /* Read Graphics Base of Stolen Memory directly */
64 pci_read_config_dword(dev->pdev, 0x5c, &base);
65 base &= ~((1<<20) - 1);
68 /* Stolen is immediately above Top of Memory */
69 base = max_low_pfn_mapped << PAGE_SHIFT;
76 /* make sure we don't clobber the GTT if it's within stolen memory */
77 if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
81 { .start = base, .end = base + dev_priv->gtt.stolen_size, },
82 { .start = base, .end = base + dev_priv->gtt.stolen_size, },
84 u64 gtt_start, gtt_end;
86 gtt_start = I915_READ(PGTBL_CTL);
88 gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
89 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
91 gtt_start &= PGTBL_ADDRESS_LO_MASK;
92 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
94 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
95 stolen[0].end = gtt_start;
96 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
97 stolen[1].start = gtt_end;
99 /* pick the larger of the two chunks */
100 if (stolen[0].end - stolen[0].start >
101 stolen[1].end - stolen[1].start) {
102 base = stolen[0].start;
103 dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
105 base = stolen[1].start;
106 dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
109 if (stolen[0].start != stolen[1].start ||
110 stolen[0].end != stolen[1].end) {
111 DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
112 (unsigned long long) gtt_start,
113 (unsigned long long) gtt_end - 1);
114 DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
115 base, base + (u32) dev_priv->gtt.stolen_size - 1);
120 /* Verify that nothing else uses this physical address. Stolen
121 * memory should be reserved by the BIOS and hidden from the
122 * kernel. So if the region is already marked as busy, something
123 * is seriously wrong.
126 r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
127 "Graphics Stolen Memory");
130 * One more attempt but this time requesting region from
131 * base + 1, as we have seen that this resolves the region
132 * conflict with the PCI Bus.
133 * This is a BIOS w/a: Some BIOS wrap stolen in the root
134 * PCI bus, but have an off-by-one error. Hence retry the
135 * reservation starting from 1 instead of 0.
137 r = devm_request_mem_region(dev->dev, base + 1,
138 dev_priv->gtt.stolen_size - 1,
139 "Graphics Stolen Memory");
141 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
142 base, base + (uint32_t)dev_priv->gtt.stolen_size);
151 static int find_compression_threshold(struct drm_device *dev,
152 struct drm_mm_node *node,
156 struct drm_i915_private *dev_priv = dev->dev_private;
157 int compression_threshold = 1;
160 /* HACK: This code depends on what we will do in *_enable_fbc. If that
161 * code changes, this code needs to change as well.
163 * The enable_fbc code will attempt to use one of our 2 compression
164 * thresholds, therefore, in that case, we only have 1 resort.
167 /* Try to over-allocate to reduce reallocations and fragmentation. */
168 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
169 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
171 return compression_threshold;
174 /* HW's ability to limit the CFB is 1:4 */
175 if (compression_threshold > 4 ||
176 (fb_cpp == 2 && compression_threshold == 2))
179 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
181 DRM_MM_SEARCH_DEFAULT);
182 if (ret && INTEL_INFO(dev)->gen <= 4) {
185 compression_threshold <<= 1;
188 return compression_threshold;
192 static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp)
194 struct drm_i915_private *dev_priv = dev->dev_private;
195 struct drm_mm_node *compressed_llb;
198 ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb,
203 DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n");
207 dev_priv->fbc.threshold = ret;
209 if (HAS_PCH_SPLIT(dev))
210 I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
211 else if (IS_GM45(dev)) {
212 I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
214 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
218 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
219 4096, 4096, DRM_MM_SEARCH_DEFAULT);
223 dev_priv->fbc.compressed_llb = compressed_llb;
225 I915_WRITE(FBC_CFB_BASE,
226 dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start);
227 I915_WRITE(FBC_LL_BASE,
228 dev_priv->mm.stolen_base + compressed_llb->start);
231 dev_priv->fbc.size = size / dev_priv->fbc.threshold;
233 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
239 kfree(compressed_llb);
240 drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
242 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);
246 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp)
248 struct drm_i915_private *dev_priv = dev->dev_private;
250 if (!drm_mm_initialized(&dev_priv->mm.stolen))
253 if (size < dev_priv->fbc.size)
256 /* Release any current block */
257 i915_gem_stolen_cleanup_compression(dev);
259 return i915_setup_compression(dev, size, fb_cpp);
262 void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
264 struct drm_i915_private *dev_priv = dev->dev_private;
266 if (dev_priv->fbc.size == 0)
269 drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
271 if (dev_priv->fbc.compressed_llb) {
272 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
273 kfree(dev_priv->fbc.compressed_llb);
276 dev_priv->fbc.size = 0;
279 void i915_gem_cleanup_stolen(struct drm_device *dev)
281 struct drm_i915_private *dev_priv = dev->dev_private;
283 if (!drm_mm_initialized(&dev_priv->mm.stolen))
286 i915_gem_stolen_cleanup_compression(dev);
287 drm_mm_takedown(&dev_priv->mm.stolen);
290 int i915_gem_init_stolen(struct drm_device *dev)
292 struct drm_i915_private *dev_priv = dev->dev_private;
294 int bios_reserved = 0;
296 #ifdef CONFIG_INTEL_IOMMU
297 if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
298 DRM_INFO("DMAR active, disabling use of stolen memory\n");
303 if (dev_priv->gtt.stolen_size == 0)
306 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
307 if (dev_priv->mm.stolen_base == 0)
310 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
311 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
313 if (INTEL_INFO(dev)->gen >= 8) {
314 tmp = I915_READ(GEN7_BIOS_RESERVED);
315 tmp >>= GEN8_BIOS_RESERVED_SHIFT;
316 tmp &= GEN8_BIOS_RESERVED_MASK;
317 bios_reserved = (1024*1024) << tmp;
318 } else if (IS_GEN7(dev)) {
319 tmp = I915_READ(GEN7_BIOS_RESERVED);
320 bios_reserved = tmp & GEN7_BIOS_RESERVED_256K ?
321 256*1024 : 1024*1024;
324 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
327 /* Basic memrange allocator for stolen space */
328 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
335 static struct sg_table *
336 i915_pages_create_for_stolen(struct drm_device *dev,
337 u32 offset, u32 size)
339 struct drm_i915_private *dev_priv = dev->dev_private;
341 struct scatterlist *sg;
343 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
344 BUG_ON(offset > dev_priv->gtt.stolen_size - size);
346 /* We hide that we have no struct page backing our stolen object
347 * by wrapping the contiguous physical allocation with a fake
348 * dma mapping in a single scatterlist.
351 st = kmalloc(sizeof(*st), GFP_KERNEL);
355 if (sg_alloc_table(st, 1, GFP_KERNEL)) {
364 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
365 sg_dma_len(sg) = size;
371 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
377 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
380 /* Should only be called during free */
381 sg_free_table(obj->pages);
390 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
393 drm_mm_remove_node(obj->stolen);
398 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
399 .get_pages = i915_gem_object_get_pages_stolen,
400 .put_pages = i915_gem_object_put_pages_stolen,
401 .release = i915_gem_object_release_stolen,
404 static struct drm_i915_gem_object *
405 _i915_gem_object_create_stolen(struct drm_device *dev,
406 struct drm_mm_node *stolen)
408 struct drm_i915_gem_object *obj;
411 obj = i915_gem_object_alloc(dev);
418 drm_gem_private_object_init(dev, &obj->base, stolen->size);
419 i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
422 obj->pages = i915_pages_create_for_stolen(dev,
423 stolen->start, stolen->size);
427 if (obj->pages == NULL)
430 obj->has_dma_mapping = true;
431 i915_gem_object_pin_pages(obj);
432 obj->stolen = stolen;
434 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
435 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
440 i915_gem_object_free(obj);
444 struct drm_i915_gem_object *
445 i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
447 struct drm_i915_private *dev_priv = dev->dev_private;
448 struct drm_i915_gem_object *obj;
449 struct drm_mm_node *stolen;
452 if (!drm_mm_initialized(&dev_priv->mm.stolen))
455 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
459 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
463 ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
464 4096, DRM_MM_SEARCH_DEFAULT);
470 obj = _i915_gem_object_create_stolen(dev, stolen);
474 drm_mm_remove_node(stolen);
479 struct drm_i915_gem_object *
480 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
485 struct drm_i915_private *dev_priv = dev->dev_private;
486 struct i915_address_space *ggtt = &dev_priv->gtt.base;
487 struct drm_i915_gem_object *obj;
488 struct drm_mm_node *stolen;
489 struct i915_vma *vma;
492 if (!drm_mm_initialized(&dev_priv->mm.stolen))
495 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
496 stolen_offset, gtt_offset, size);
498 /* KISS and expect everything to be page-aligned */
499 BUG_ON(stolen_offset & 4095);
502 if (WARN_ON(size == 0))
505 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
509 stolen->start = stolen_offset;
511 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
513 DRM_DEBUG_KMS("failed to allocate stolen space\n");
518 obj = _i915_gem_object_create_stolen(dev, stolen);
520 DRM_DEBUG_KMS("failed to allocate stolen object\n");
521 drm_mm_remove_node(stolen);
526 /* Some objects just need physical mem from stolen space */
527 if (gtt_offset == I915_GTT_OFFSET_NONE)
530 vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
536 /* To simplify the initialisation sequence between KMS and GTT,
537 * we allow construction of the stolen object prior to
538 * setting up the GTT space. The actual reservation will occur
541 vma->node.start = gtt_offset;
542 vma->node.size = size;
543 if (drm_mm_initialized(&ggtt->mm)) {
544 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
546 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
551 obj->has_global_gtt_mapping = 1;
553 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
554 list_add_tail(&vma->mm_list, &ggtt->inactive_list);
555 i915_gem_object_pin_pages(obj);
560 i915_gem_vma_destroy(vma);
562 drm_mm_remove_node(stolen);
564 drm_gem_object_unreference(&obj->base);