Merge remote-tracking branch 'asoc/topic/core' into asoc-next
[linux-2.6-block.git] / drivers / gpu / drm / i915 / i915_gem_stolen.c
CommitLineData
9797fbfb
CW
1/*
2 * Copyright © 2008-2012 Intel Corporation
3 *
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:
10 *
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
13 * Software.
14 *
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
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 * Chris Wilson <chris@chris-wilson.co.uk>
26 *
27 */
28
760285e7
DH
29#include <drm/drmP.h>
30#include <drm/i915_drm.h>
9797fbfb
CW
31#include "i915_drv.h"
32
33/*
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.
38 *
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
42 * for is a boon.
43 */
44
e12a2d53 45static unsigned long i915_stolen_to_physical(struct drm_device *dev)
9797fbfb
CW
46{
47 struct drm_i915_private *dev_priv = dev->dev_private;
eaba1b8f 48 struct resource *r;
9797fbfb
CW
49 u32 base;
50
17fec8a0
CW
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
58 * by the e820 probe.
e12a2d53 59 *
17fec8a0 60 * XXX However gen2 requires an unavailable symbol.
9797fbfb 61 */
e12a2d53 62 base = 0;
17fec8a0
CW
63 if (INTEL_INFO(dev)->gen >= 3) {
64 /* Read Graphics Base of Stolen Memory directly */
c9cddffc
JB
65 pci_read_config_dword(dev->pdev, 0x5c, &base);
66 base &= ~((1<<20) - 1);
17fec8a0 67 } else { /* GEN2 */
e12a2d53 68#if 0
e12a2d53
CW
69 /* Stolen is immediately above Top of Memory */
70 base = max_low_pfn_mapped << PAGE_SHIFT;
9797fbfb 71#endif
e12a2d53 72 }
9797fbfb 73
eaba1b8f
CW
74 if (base == 0)
75 return 0;
76
f1e1c212
VS
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)) {
79 struct {
80 u32 start, end;
81 } stolen[2] = {
82 { .start = base, .end = base + dev_priv->gtt.stolen_size, },
83 { .start = base, .end = base + dev_priv->gtt.stolen_size, },
84 };
85 u64 gtt_start, gtt_end;
86
87 gtt_start = I915_READ(PGTBL_CTL);
88 if (IS_GEN4(dev))
89 gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
90 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
91 else
92 gtt_start &= PGTBL_ADDRESS_LO_MASK;
93 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
94
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;
99
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;
105 } else {
106 base = stolen[1].start;
107 dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
108 }
109
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);
117 }
118 }
119
120
eaba1b8f
CW
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.
125 */
126 r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
127 "Graphics Stolen Memory");
128 if (r == NULL) {
3617dc96
AG
129 /*
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.
136 */
137 r = devm_request_mem_region(dev->dev, base + 1,
138 dev_priv->gtt.stolen_size - 1,
139 "Graphics Stolen Memory");
0b6d24c0
DV
140 /*
141 * GEN3 firmware likes to smash pci bridges into the stolen
142 * range. Apparently this works.
143 */
144 if (r == NULL && !IS_GEN3(dev)) {
3617dc96
AG
145 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
146 base, base + (uint32_t)dev_priv->gtt.stolen_size);
147 base = 0;
148 }
eaba1b8f
CW
149 }
150
e12a2d53 151 return base;
9797fbfb
CW
152}
153
edc0fdbb
BW
154static int find_compression_threshold(struct drm_device *dev,
155 struct drm_mm_node *node,
5e59f717
BW
156 int size,
157 int fb_cpp)
9797fbfb
CW
158{
159 struct drm_i915_private *dev_priv = dev->dev_private;
5e59f717 160 int compression_threshold = 1;
06e78edf 161 int ret;
9797fbfb 162
5e59f717
BW
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.
165 *
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.
168 */
169
170 /* Try to over-allocate to reduce reallocations and fragmentation. */
edc0fdbb 171 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
06e78edf 172 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
5e59f717
BW
173 if (ret == 0)
174 return compression_threshold;
175
176again:
177 /* HW's ability to limit the CFB is 1:4 */
178 if (compression_threshold > 4 ||
179 (fb_cpp == 2 && compression_threshold == 2))
edc0fdbb 180 return 0;
5e59f717
BW
181
182 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
183 size >>= 1, 4096,
184 DRM_MM_SEARCH_DEFAULT);
185 if (ret && INTEL_INFO(dev)->gen <= 4) {
186 return 0;
187 } else if (ret) {
188 compression_threshold <<= 1;
189 goto again;
190 } else {
edc0fdbb 191 return compression_threshold;
5e59f717 192 }
edc0fdbb
BW
193}
194
5e59f717 195static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp)
edc0fdbb
BW
196{
197 struct drm_i915_private *dev_priv = dev->dev_private;
198 struct drm_mm_node *uninitialized_var(compressed_llb);
199 int ret;
200
201 ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb,
5e59f717 202 size, fb_cpp);
edc0fdbb 203 if (!ret)
06e78edf 204 goto err_llb;
5e59f717
BW
205 else if (ret > 1) {
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");
207
208 }
209
210 dev_priv->fbc.threshold = ret;
9797fbfb 211
46ec15f2 212 if (INTEL_INFO(dev_priv)->gen >= 5)
c4213885 213 I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
11be49eb 214 else if (IS_GM45(dev)) {
c4213885 215 I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
11be49eb 216 } else {
06e78edf 217 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
9797fbfb
CW
218 if (!compressed_llb)
219 goto err_fb;
220
06e78edf
DH
221 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
222 4096, 4096, DRM_MM_SEARCH_DEFAULT);
223 if (ret)
224 goto err_fb;
225
5c3fe8b0 226 dev_priv->fbc.compressed_llb = compressed_llb;
11be49eb
CW
227
228 I915_WRITE(FBC_CFB_BASE,
c4213885 229 dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start);
11be49eb
CW
230 I915_WRITE(FBC_LL_BASE,
231 dev_priv->mm.stolen_base + compressed_llb->start);
9797fbfb
CW
232 }
233
60ee5cd2 234 dev_priv->fbc.uncompressed_size = size;
9797fbfb 235
11be49eb
CW
236 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
237 size);
9797fbfb 238
11be49eb 239 return 0;
9797fbfb 240
9797fbfb 241err_fb:
06e78edf 242 kfree(compressed_llb);
c4213885 243 drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
06e78edf 244err_llb:
d8241785 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);
11be49eb
CW
246 return -ENOSPC;
247}
248
5e59f717 249int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp)
11be49eb
CW
250{
251 struct drm_i915_private *dev_priv = dev->dev_private;
252
446f8d81 253 if (!drm_mm_initialized(&dev_priv->mm.stolen))
11be49eb
CW
254 return -ENODEV;
255
cb0a08c1 256 if (size <= dev_priv->fbc.uncompressed_size)
11be49eb
CW
257 return 0;
258
259 /* Release any current block */
260 i915_gem_stolen_cleanup_compression(dev);
261
5e59f717 262 return i915_setup_compression(dev, size, fb_cpp);
9797fbfb
CW
263}
264
11be49eb 265void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
9797fbfb
CW
266{
267 struct drm_i915_private *dev_priv = dev->dev_private;
268
60ee5cd2 269 if (dev_priv->fbc.uncompressed_size == 0)
11be49eb
CW
270 return;
271
c4213885 272 drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
11be49eb 273
06e78edf
DH
274 if (dev_priv->fbc.compressed_llb) {
275 drm_mm_remove_node(dev_priv->fbc.compressed_llb);
276 kfree(dev_priv->fbc.compressed_llb);
277 }
11be49eb 278
60ee5cd2 279 dev_priv->fbc.uncompressed_size = 0;
9797fbfb
CW
280}
281
282void i915_gem_cleanup_stolen(struct drm_device *dev)
283{
4d7bb011
DV
284 struct drm_i915_private *dev_priv = dev->dev_private;
285
446f8d81
DV
286 if (!drm_mm_initialized(&dev_priv->mm.stolen))
287 return;
288
11be49eb 289 i915_gem_stolen_cleanup_compression(dev);
4d7bb011 290 drm_mm_takedown(&dev_priv->mm.stolen);
9797fbfb
CW
291}
292
293int i915_gem_init_stolen(struct drm_device *dev)
294{
295 struct drm_i915_private *dev_priv = dev->dev_private;
40bae736 296 u32 tmp;
c9cddffc 297 int bios_reserved = 0;
9797fbfb 298
0f4706d2 299#ifdef CONFIG_INTEL_IOMMU
fcc9fe1a 300 if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
0f4706d2
CW
301 DRM_INFO("DMAR active, disabling use of stolen memory\n");
302 return 0;
303 }
304#endif
305
6644a4e9
CW
306 if (dev_priv->gtt.stolen_size == 0)
307 return 0;
308
e12a2d53
CW
309 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
310 if (dev_priv->mm.stolen_base == 0)
311 return 0;
312
a54c0c27
BW
313 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
314 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
e12a2d53 315
40bae736
DV
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;
325 }
c9cddffc 326
897f9ed0
DV
327 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
328 return 0;
329
9797fbfb 330 /* Basic memrange allocator for stolen space */
c9cddffc
JB
331 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
332 bios_reserved);
9797fbfb
CW
333
334 return 0;
335}
0104fdbb
CW
336
337static struct sg_table *
338i915_pages_create_for_stolen(struct drm_device *dev,
339 u32 offset, u32 size)
340{
341 struct drm_i915_private *dev_priv = dev->dev_private;
342 struct sg_table *st;
343 struct scatterlist *sg;
344
345 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
a54c0c27 346 BUG_ON(offset > dev_priv->gtt.stolen_size - size);
0104fdbb
CW
347
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.
351 */
352
353 st = kmalloc(sizeof(*st), GFP_KERNEL);
354 if (st == NULL)
355 return NULL;
356
357 if (sg_alloc_table(st, 1, GFP_KERNEL)) {
358 kfree(st);
359 return NULL;
360 }
361
362 sg = st->sgl;
ec14ba47 363 sg->offset = 0;
ed23abdd 364 sg->length = size;
0104fdbb
CW
365
366 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
367 sg_dma_len(sg) = size;
368
369 return st;
370}
371
372static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
373{
374 BUG();
375 return -EINVAL;
376}
377
378static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
379{
380 /* Should only be called during free */
381 sg_free_table(obj->pages);
382 kfree(obj->pages);
383}
384
ef0cf27c
CW
385
386static void
387i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
388{
389 if (obj->stolen) {
390 drm_mm_remove_node(obj->stolen);
391 kfree(obj->stolen);
392 obj->stolen = NULL;
393 }
394}
0104fdbb
CW
395static 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,
ef0cf27c 398 .release = i915_gem_object_release_stolen,
0104fdbb
CW
399};
400
401static struct drm_i915_gem_object *
402_i915_gem_object_create_stolen(struct drm_device *dev,
403 struct drm_mm_node *stolen)
404{
405 struct drm_i915_gem_object *obj;
406
42dcedd4 407 obj = i915_gem_object_alloc(dev);
0104fdbb
CW
408 if (obj == NULL)
409 return NULL;
410
89c8233f 411 drm_gem_private_object_init(dev, &obj->base, stolen->size);
0104fdbb
CW
412 i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
413
414 obj->pages = i915_pages_create_for_stolen(dev,
415 stolen->start, stolen->size);
416 if (obj->pages == NULL)
417 goto cleanup;
418
dd53e1b0 419 i915_gem_object_pin_pages(obj);
0104fdbb
CW
420 obj->stolen = stolen;
421
d46f1c3f
CW
422 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
423 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
0104fdbb
CW
424
425 return obj;
426
427cleanup:
42dcedd4 428 i915_gem_object_free(obj);
0104fdbb
CW
429 return NULL;
430}
431
432struct drm_i915_gem_object *
433i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
434{
435 struct drm_i915_private *dev_priv = dev->dev_private;
436 struct drm_i915_gem_object *obj;
437 struct drm_mm_node *stolen;
06e78edf 438 int ret;
0104fdbb 439
446f8d81 440 if (!drm_mm_initialized(&dev_priv->mm.stolen))
0104fdbb
CW
441 return NULL;
442
443 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
444 if (size == 0)
445 return NULL;
446
06e78edf
DH
447 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
448 if (!stolen)
0104fdbb
CW
449 return NULL;
450
06e78edf
DH
451 ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
452 4096, DRM_MM_SEARCH_DEFAULT);
453 if (ret) {
454 kfree(stolen);
455 return NULL;
456 }
457
0104fdbb
CW
458 obj = _i915_gem_object_create_stolen(dev, stolen);
459 if (obj)
460 return obj;
461
06e78edf
DH
462 drm_mm_remove_node(stolen);
463 kfree(stolen);
0104fdbb
CW
464 return NULL;
465}
466
866d12b4
CW
467struct drm_i915_gem_object *
468i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
469 u32 stolen_offset,
470 u32 gtt_offset,
471 u32 size)
472{
473 struct drm_i915_private *dev_priv = dev->dev_private;
40d74980 474 struct i915_address_space *ggtt = &dev_priv->gtt.base;
866d12b4
CW
475 struct drm_i915_gem_object *obj;
476 struct drm_mm_node *stolen;
2f633156 477 struct i915_vma *vma;
b3a070cc 478 int ret;
866d12b4 479
446f8d81 480 if (!drm_mm_initialized(&dev_priv->mm.stolen))
866d12b4
CW
481 return NULL;
482
483 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
484 stolen_offset, gtt_offset, size);
485
486 /* KISS and expect everything to be page-aligned */
f37b5c2b
DV
487 if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
488 WARN_ON(stolen_offset & 4095))
866d12b4
CW
489 return NULL;
490
b3a070cc
BW
491 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
492 if (!stolen)
493 return NULL;
494
338710e7
BW
495 stolen->start = stolen_offset;
496 stolen->size = size;
497 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
b3a070cc 498 if (ret) {
866d12b4 499 DRM_DEBUG_KMS("failed to allocate stolen space\n");
b3a070cc 500 kfree(stolen);
866d12b4
CW
501 return NULL;
502 }
503
504 obj = _i915_gem_object_create_stolen(dev, stolen);
505 if (obj == NULL) {
506 DRM_DEBUG_KMS("failed to allocate stolen object\n");
06e78edf
DH
507 drm_mm_remove_node(stolen);
508 kfree(stolen);
866d12b4
CW
509 return NULL;
510 }
511
3727d55e 512 /* Some objects just need physical mem from stolen space */
190d6cd5 513 if (gtt_offset == I915_GTT_OFFSET_NONE)
3727d55e
JB
514 return obj;
515
e656a6cb 516 vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
db473b36
DC
517 if (IS_ERR(vma)) {
518 ret = PTR_ERR(vma);
2f633156
BW
519 goto err_out;
520 }
521
866d12b4
CW
522 /* To simplify the initialisation sequence between KMS and GTT,
523 * we allow construction of the stolen object prior to
524 * setting up the GTT space. The actual reservation will occur
525 * later.
526 */
2f633156
BW
527 vma->node.start = gtt_offset;
528 vma->node.size = size;
40d74980
BW
529 if (drm_mm_initialized(&ggtt->mm)) {
530 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
b3a070cc 531 if (ret) {
866d12b4 532 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
4a025e26 533 goto err_vma;
866d12b4 534 }
edd41a87 535 }
866d12b4 536
aff43766 537 vma->bound |= GLOBAL_BIND;
866d12b4 538
35c20a60 539 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
ca191b13 540 list_add_tail(&vma->mm_list, &ggtt->inactive_list);
d8ccba86 541 i915_gem_object_pin_pages(obj);
866d12b4
CW
542
543 return obj;
b3a070cc 544
4a025e26
DV
545err_vma:
546 i915_gem_vma_destroy(vma);
f7f18184 547err_out:
32c913e4
DA
548 drm_mm_remove_node(stolen);
549 kfree(stolen);
b3a070cc
BW
550 drm_gem_object_unreference(&obj->base);
551 return NULL;
866d12b4 552}