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 /* make sure we don't clobber the GTT if it's within stolen memory */
78 if (INTEL_INFO(dev
)->gen
<= 4 && !IS_G33(dev
) && !IS_G4X(dev
)) {
82 { .start
= base
, .end
= base
+ dev_priv
->gtt
.stolen_size
, },
83 { .start
= base
, .end
= base
+ dev_priv
->gtt
.stolen_size
, },
85 u64 gtt_start
, gtt_end
;
87 gtt_start
= I915_READ(PGTBL_CTL
);
89 gtt_start
= (gtt_start
& PGTBL_ADDRESS_LO_MASK
) |
90 (gtt_start
& PGTBL_ADDRESS_HI_MASK
) << 28;
92 gtt_start
&= PGTBL_ADDRESS_LO_MASK
;
93 gtt_end
= gtt_start
+ gtt_total_entries(dev_priv
->gtt
) * 4;
95 if (gtt_start
>= stolen
[0].start
&& gtt_start
< stolen
[0].end
)
96 stolen
[0].end
= gtt_start
;
97 if (gtt_end
> stolen
[1].start
&& gtt_end
<= stolen
[1].end
)
98 stolen
[1].start
= gtt_end
;
100 /* pick the larger of the two chunks */
101 if (stolen
[0].end
- stolen
[0].start
>
102 stolen
[1].end
- stolen
[1].start
) {
103 base
= stolen
[0].start
;
104 dev_priv
->gtt
.stolen_size
= stolen
[0].end
- stolen
[0].start
;
106 base
= stolen
[1].start
;
107 dev_priv
->gtt
.stolen_size
= stolen
[1].end
- stolen
[1].start
;
110 if (stolen
[0].start
!= stolen
[1].start
||
111 stolen
[0].end
!= stolen
[1].end
) {
112 DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
113 (unsigned long long) gtt_start
,
114 (unsigned long long) gtt_end
- 1);
115 DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
116 base
, base
+ (u32
) dev_priv
->gtt
.stolen_size
- 1);
121 /* Verify that nothing else uses this physical address. Stolen
122 * memory should be reserved by the BIOS and hidden from the
123 * kernel. So if the region is already marked as busy, something
124 * 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 * GEN3 firmware likes to smash pci bridges into the stolen
142 * range. Apparently this works.
144 if (r
== NULL
&& !IS_GEN3(dev
)) {
145 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
146 base
, base
+ (uint32_t)dev_priv
->gtt
.stolen_size
);
154 static int find_compression_threshold(struct drm_device
*dev
,
155 struct drm_mm_node
*node
,
159 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
160 int compression_threshold
= 1;
163 /* HACK: This code depends on what we will do in *_enable_fbc. If that
164 * code changes, this code needs to change as well.
166 * The enable_fbc code will attempt to use one of our 2 compression
167 * thresholds, therefore, in that case, we only have 1 resort.
170 /* Try to over-allocate to reduce reallocations and fragmentation. */
171 ret
= drm_mm_insert_node(&dev_priv
->mm
.stolen
, node
,
172 size
<<= 1, 4096, DRM_MM_SEARCH_DEFAULT
);
174 return compression_threshold
;
177 /* HW's ability to limit the CFB is 1:4 */
178 if (compression_threshold
> 4 ||
179 (fb_cpp
== 2 && compression_threshold
== 2))
182 ret
= drm_mm_insert_node(&dev_priv
->mm
.stolen
, node
,
184 DRM_MM_SEARCH_DEFAULT
);
185 if (ret
&& INTEL_INFO(dev
)->gen
<= 4) {
188 compression_threshold
<<= 1;
191 return compression_threshold
;
195 static int i915_setup_compression(struct drm_device
*dev
, int size
, int fb_cpp
)
197 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
198 struct drm_mm_node
*uninitialized_var(compressed_llb
);
201 ret
= find_compression_threshold(dev
, &dev_priv
->fbc
.compressed_fb
,
206 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");
210 dev_priv
->fbc
.threshold
= ret
;
212 if (HAS_PCH_SPLIT(dev
))
213 I915_WRITE(ILK_DPFC_CB_BASE
, dev_priv
->fbc
.compressed_fb
.start
);
214 else if (IS_GM45(dev
)) {
215 I915_WRITE(DPFC_CB_BASE
, dev_priv
->fbc
.compressed_fb
.start
);
217 compressed_llb
= kzalloc(sizeof(*compressed_llb
), GFP_KERNEL
);
221 ret
= drm_mm_insert_node(&dev_priv
->mm
.stolen
, compressed_llb
,
222 4096, 4096, DRM_MM_SEARCH_DEFAULT
);
226 dev_priv
->fbc
.compressed_llb
= compressed_llb
;
228 I915_WRITE(FBC_CFB_BASE
,
229 dev_priv
->mm
.stolen_base
+ dev_priv
->fbc
.compressed_fb
.start
);
230 I915_WRITE(FBC_LL_BASE
,
231 dev_priv
->mm
.stolen_base
+ compressed_llb
->start
);
234 dev_priv
->fbc
.size
= size
/ dev_priv
->fbc
.threshold
;
236 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
242 kfree(compressed_llb
);
243 drm_mm_remove_node(&dev_priv
->fbc
.compressed_fb
);
245 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
);
249 int i915_gem_stolen_setup_compression(struct drm_device
*dev
, int size
, int fb_cpp
)
251 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
253 if (!drm_mm_initialized(&dev_priv
->mm
.stolen
))
256 if (size
< dev_priv
->fbc
.size
)
259 /* Release any current block */
260 i915_gem_stolen_cleanup_compression(dev
);
262 return i915_setup_compression(dev
, size
, fb_cpp
);
265 void i915_gem_stolen_cleanup_compression(struct drm_device
*dev
)
267 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
269 if (dev_priv
->fbc
.size
== 0)
272 drm_mm_remove_node(&dev_priv
->fbc
.compressed_fb
);
274 if (dev_priv
->fbc
.compressed_llb
) {
275 drm_mm_remove_node(dev_priv
->fbc
.compressed_llb
);
276 kfree(dev_priv
->fbc
.compressed_llb
);
279 dev_priv
->fbc
.size
= 0;
282 void i915_gem_cleanup_stolen(struct drm_device
*dev
)
284 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
286 if (!drm_mm_initialized(&dev_priv
->mm
.stolen
))
289 i915_gem_stolen_cleanup_compression(dev
);
290 drm_mm_takedown(&dev_priv
->mm
.stolen
);
293 int i915_gem_init_stolen(struct drm_device
*dev
)
295 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
297 int bios_reserved
= 0;
299 #ifdef CONFIG_INTEL_IOMMU
300 if (intel_iommu_gfx_mapped
&& INTEL_INFO(dev
)->gen
< 8) {
301 DRM_INFO("DMAR active, disabling use of stolen memory\n");
306 if (dev_priv
->gtt
.stolen_size
== 0)
309 dev_priv
->mm
.stolen_base
= i915_stolen_to_physical(dev
);
310 if (dev_priv
->mm
.stolen_base
== 0)
313 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
314 dev_priv
->gtt
.stolen_size
, dev_priv
->mm
.stolen_base
);
316 if (INTEL_INFO(dev
)->gen
>= 8) {
317 tmp
= I915_READ(GEN7_BIOS_RESERVED
);
318 tmp
>>= GEN8_BIOS_RESERVED_SHIFT
;
319 tmp
&= GEN8_BIOS_RESERVED_MASK
;
320 bios_reserved
= (1024*1024) << tmp
;
321 } else if (IS_GEN7(dev
)) {
322 tmp
= I915_READ(GEN7_BIOS_RESERVED
);
323 bios_reserved
= tmp
& GEN7_BIOS_RESERVED_256K
?
324 256*1024 : 1024*1024;
327 if (WARN_ON(bios_reserved
> dev_priv
->gtt
.stolen_size
))
330 /* Basic memrange allocator for stolen space */
331 drm_mm_init(&dev_priv
->mm
.stolen
, 0, dev_priv
->gtt
.stolen_size
-
337 static struct sg_table
*
338 i915_pages_create_for_stolen(struct drm_device
*dev
,
339 u32 offset
, u32 size
)
341 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
343 struct scatterlist
*sg
;
345 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset
, size
);
346 BUG_ON(offset
> dev_priv
->gtt
.stolen_size
- size
);
348 /* We hide that we have no struct page backing our stolen object
349 * by wrapping the contiguous physical allocation with a fake
350 * dma mapping in a single scatterlist.
353 st
= kmalloc(sizeof(*st
), GFP_KERNEL
);
357 if (sg_alloc_table(st
, 1, GFP_KERNEL
)) {
366 sg_dma_address(sg
) = (dma_addr_t
)dev_priv
->mm
.stolen_base
+ offset
;
367 sg_dma_len(sg
) = size
;
372 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object
*obj
)
378 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
);
387 i915_gem_object_release_stolen(struct drm_i915_gem_object
*obj
)
390 drm_mm_remove_node(obj
->stolen
);
395 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops
= {
396 .get_pages
= i915_gem_object_get_pages_stolen
,
397 .put_pages
= i915_gem_object_put_pages_stolen
,
398 .release
= i915_gem_object_release_stolen
,
401 static struct drm_i915_gem_object
*
402 _i915_gem_object_create_stolen(struct drm_device
*dev
,
403 struct drm_mm_node
*stolen
)
405 struct drm_i915_gem_object
*obj
;
407 obj
= i915_gem_object_alloc(dev
);
411 drm_gem_private_object_init(dev
, &obj
->base
, stolen
->size
);
412 i915_gem_object_init(obj
, &i915_gem_object_stolen_ops
);
414 obj
->pages
= i915_pages_create_for_stolen(dev
,
415 stolen
->start
, stolen
->size
);
416 if (obj
->pages
== NULL
)
419 obj
->has_dma_mapping
= true;
420 i915_gem_object_pin_pages(obj
);
421 obj
->stolen
= stolen
;
423 obj
->base
.read_domains
= I915_GEM_DOMAIN_CPU
| I915_GEM_DOMAIN_GTT
;
424 obj
->cache_level
= HAS_LLC(dev
) ? I915_CACHE_LLC
: I915_CACHE_NONE
;
429 i915_gem_object_free(obj
);
433 struct drm_i915_gem_object
*
434 i915_gem_object_create_stolen(struct drm_device
*dev
, u32 size
)
436 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
437 struct drm_i915_gem_object
*obj
;
438 struct drm_mm_node
*stolen
;
441 if (!drm_mm_initialized(&dev_priv
->mm
.stolen
))
444 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size
);
448 stolen
= kzalloc(sizeof(*stolen
), GFP_KERNEL
);
452 ret
= drm_mm_insert_node(&dev_priv
->mm
.stolen
, stolen
, size
,
453 4096, DRM_MM_SEARCH_DEFAULT
);
459 obj
= _i915_gem_object_create_stolen(dev
, stolen
);
463 drm_mm_remove_node(stolen
);
468 struct drm_i915_gem_object
*
469 i915_gem_object_create_stolen_for_preallocated(struct drm_device
*dev
,
474 struct drm_i915_private
*dev_priv
= dev
->dev_private
;
475 struct i915_address_space
*ggtt
= &dev_priv
->gtt
.base
;
476 struct drm_i915_gem_object
*obj
;
477 struct drm_mm_node
*stolen
;
478 struct i915_vma
*vma
;
481 if (!drm_mm_initialized(&dev_priv
->mm
.stolen
))
484 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
485 stolen_offset
, gtt_offset
, size
);
487 /* KISS and expect everything to be page-aligned */
488 if (WARN_ON(size
== 0) || WARN_ON(size
& 4095) ||
489 WARN_ON(stolen_offset
& 4095))
492 stolen
= kzalloc(sizeof(*stolen
), GFP_KERNEL
);
496 stolen
->start
= stolen_offset
;
498 ret
= drm_mm_reserve_node(&dev_priv
->mm
.stolen
, stolen
);
500 DRM_DEBUG_KMS("failed to allocate stolen space\n");
505 obj
= _i915_gem_object_create_stolen(dev
, stolen
);
507 DRM_DEBUG_KMS("failed to allocate stolen object\n");
508 drm_mm_remove_node(stolen
);
513 /* Some objects just need physical mem from stolen space */
514 if (gtt_offset
== I915_GTT_OFFSET_NONE
)
517 vma
= i915_gem_obj_lookup_or_create_vma(obj
, ggtt
);
523 /* To simplify the initialisation sequence between KMS and GTT,
524 * we allow construction of the stolen object prior to
525 * setting up the GTT space. The actual reservation will occur
528 vma
->node
.start
= gtt_offset
;
529 vma
->node
.size
= size
;
530 if (drm_mm_initialized(&ggtt
->mm
)) {
531 ret
= drm_mm_reserve_node(&ggtt
->mm
, &vma
->node
);
533 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
538 vma
->bound
|= GLOBAL_BIND
;
540 list_add_tail(&obj
->global_list
, &dev_priv
->mm
.bound_list
);
541 list_add_tail(&vma
->mm_list
, &ggtt
->inactive_list
);
542 i915_gem_object_pin_pages(obj
);
547 i915_gem_vma_destroy(vma
);
549 drm_mm_remove_node(stolen
);
551 drm_gem_object_unreference(&obj
->base
);