root/drivers/gpu/drm/omapdrm/omap_gem.c

DEFINITIONS

1. omap_gem_mmap_offset
2. omap_gem_is_contiguous
3. omap_gem_evict_entry
4. omap_gem_evict
5. omap_gem_attach_pages
6. omap_gem_detach_pages
7. omap_gem_flags
8. omap_gem_mmap_size
9. omap_gem_fault_1d
10. omap_gem_fault_2d
11. omap_gem_fault
12. omap_gem_mmap
13. omap_gem_mmap_obj
14. omap_gem_dumb_create
15. omap_gem_dumb_map_offset
16. omap_gem_roll
17. omap_gem_is_cached_coherent
18. omap_gem_cpu_sync_page
19. omap_gem_dma_sync_buffer
20. omap_gem_pin
21. omap_gem_unpin
22. omap_gem_rotated_dma_addr
23. omap_gem_tiled_stride
24. omap_gem_get_pages
25. omap_gem_put_pages
26. omap_gem_vaddr
27. omap_gem_resume
28. omap_gem_describe
29. omap_gem_describe_objects
30. omap_gem_free_object
31. omap_gem_new
32. omap_gem_new_dmabuf
33. omap_gem_new_handle
34. omap_gem_init
35. omap_gem_deinit

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
   4  * Author: Rob Clark <rob.clark@linaro.org>
   5  */
   6 
   7 #include <linux/dma-mapping.h>
   8 #include <linux/seq_file.h>
   9 #include <linux/shmem_fs.h>
  10 #include <linux/spinlock.h>
  11 #include <linux/pfn_t.h>
  12 
  13 #include <drm/drm_prime.h>
  14 #include <drm/drm_vma_manager.h>
  15 
  16 #include "omap_drv.h"
  17 #include "omap_dmm_tiler.h"
  18 
  19 /*
  20  * GEM buffer object implementation.
  21  */
  22 
  23 /* note: we use upper 8 bits of flags for driver-internal flags: */
  24 #define OMAP_BO_MEM_DMA_API     0x01000000      /* memory allocated with the dma_alloc_* API */
  25 #define OMAP_BO_MEM_SHMEM       0x02000000      /* memory allocated through shmem backing */
  26 #define OMAP_BO_MEM_DMABUF      0x08000000      /* memory imported from a dmabuf */
  27 
  28 struct omap_gem_object {
  29         struct drm_gem_object base;
  30 
  31         struct list_head mm_list;
  32 
  33         u32 flags;
  34 
  35         /** width/height for tiled formats (rounded up to slot boundaries) */
  36         u16 width, height;
  37 
  38         /** roll applied when mapping to DMM */
  39         u32 roll;
  40 
  41         /** protects dma_addr_cnt, block, pages, dma_addrs and vaddr */
  42         struct mutex lock;
  43 
  44         /**
  45          * dma_addr contains the buffer DMA address. It is valid for
  46          *
  47          * - buffers allocated through the DMA mapping API (with the
  48          *   OMAP_BO_MEM_DMA_API flag set)
  49          *
  50          * - buffers imported from dmabuf (with the OMAP_BO_MEM_DMABUF flag set)
  51          *   if they are physically contiguous (when sgt->orig_nents == 1)
  52          *
  53          * - buffers mapped through the TILER when dma_addr_cnt is not zero, in
  54          *   which case the DMA address points to the TILER aperture
  55          *
  56          * Physically contiguous buffers have their DMA address equal to the
  57          * physical address as we don't remap those buffers through the TILER.
  58          *
  59          * Buffers mapped to the TILER have their DMA address pointing to the
  60          * TILER aperture. As TILER mappings are refcounted (through
  61          * dma_addr_cnt) the DMA address must be accessed through omap_gem_pin()
  62          * to ensure that the mapping won't disappear unexpectedly. References
  63          * must be released with omap_gem_unpin().
  64          */
  65         dma_addr_t dma_addr;
  66 
  67         /**
  68          * # of users of dma_addr
  69          */
  70         u32 dma_addr_cnt;
  71 
  72         /**
  73          * If the buffer has been imported from a dmabuf the OMAP_DB_DMABUF flag
  74          * is set and the sgt field is valid.
  75          */
  76         struct sg_table *sgt;
  77 
  78         /**
  79          * tiler block used when buffer is remapped in DMM/TILER.
  80          */
  81         struct tiler_block *block;
  82 
  83         /**
  84          * Array of backing pages, if allocated.  Note that pages are never
  85          * allocated for buffers originally allocated from contiguous memory
  86          */
  87         struct page **pages;
  88 
  89         /** addresses corresponding to pages in above array */
  90         dma_addr_t *dma_addrs;
  91 
  92         /**
  93          * Virtual address, if mapped.
  94          */
  95         void *vaddr;
  96 };
  97 
  98 #define to_omap_bo(x) container_of(x, struct omap_gem_object, base)
  99 
 100 /* To deal with userspace mmap'ings of 2d tiled buffers, which (a) are
 101  * not necessarily pinned in TILER all the time, and (b) when they are
 102  * they are not necessarily page aligned, we reserve one or more small
 103  * regions in each of the 2d containers to use as a user-GART where we
 104  * can create a second page-aligned mapping of parts of the buffer
 105  * being accessed from userspace.
 106  *
 107  * Note that we could optimize slightly when we know that multiple
 108  * tiler containers are backed by the same PAT.. but I'll leave that
 109  * for later..
 110  */
 111 #define NUM_USERGART_ENTRIES 2
 112 struct omap_drm_usergart_entry {
 113         struct tiler_block *block;      /* the reserved tiler block */
 114         dma_addr_t dma_addr;
 115         struct drm_gem_object *obj;     /* the current pinned obj */
 116         pgoff_t obj_pgoff;              /* page offset of obj currently
 117                                            mapped in */
 118 };
 119 
 120 struct omap_drm_usergart {
 121         struct omap_drm_usergart_entry entry[NUM_USERGART_ENTRIES];
 122         int height;                             /* height in rows */
 123         int height_shift;               /* ilog2(height in rows) */
 124         int slot_shift;                 /* ilog2(width per slot) */
 125         int stride_pfn;                 /* stride in pages */
 126         int last;                               /* index of last used entry */
 127 };
 128 
 129 /* -----------------------------------------------------------------------------
 130  * Helpers
 131  */
 132 
 133 /** get mmap offset */
 134 u64 omap_gem_mmap_offset(struct drm_gem_object *obj)
 135 {
 136         struct drm_device *dev = obj->dev;
 137         int ret;
 138         size_t size;
 139 
 140         /* Make it mmapable */
 141         size = omap_gem_mmap_size(obj);
 142         ret = drm_gem_create_mmap_offset_size(obj, size);
 143         if (ret) {
 144                 dev_err(dev->dev, "could not allocate mmap offset\n");
 145                 return 0;
 146         }
 147 
 148         return drm_vma_node_offset_addr(&obj->vma_node);
 149 }
 150 
 151 static bool omap_gem_is_contiguous(struct omap_gem_object *omap_obj)
 152 {
 153         if (omap_obj->flags & OMAP_BO_MEM_DMA_API)
 154                 return true;
 155 
 156         if ((omap_obj->flags & OMAP_BO_MEM_DMABUF) && omap_obj->sgt->nents == 1)
 157                 return true;
 158 
 159         return false;
 160 }
 161 
 162 /* -----------------------------------------------------------------------------
 163  * Eviction
 164  */
 165 
 166 static void omap_gem_evict_entry(struct drm_gem_object *obj,
 167                 enum tiler_fmt fmt, struct omap_drm_usergart_entry *entry)
 168 {
 169         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 170         struct omap_drm_private *priv = obj->dev->dev_private;
 171         int n = priv->usergart[fmt].height;
 172         size_t size = PAGE_SIZE * n;
 173         loff_t off = omap_gem_mmap_offset(obj) +
 174                         (entry->obj_pgoff << PAGE_SHIFT);
 175         const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE);
 176 
 177         if (m > 1) {
 178                 int i;
 179                 /* if stride > than PAGE_SIZE then sparse mapping: */
 180                 for (i = n; i > 0; i--) {
 181                         unmap_mapping_range(obj->dev->anon_inode->i_mapping,
 182                                             off, PAGE_SIZE, 1);
 183                         off += PAGE_SIZE * m;
 184                 }
 185         } else {
 186                 unmap_mapping_range(obj->dev->anon_inode->i_mapping,
 187                                     off, size, 1);
 188         }
 189 
 190         entry->obj = NULL;
 191 }
 192 
 193 /* Evict a buffer from usergart, if it is mapped there */
 194 static void omap_gem_evict(struct drm_gem_object *obj)
 195 {
 196         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 197         struct omap_drm_private *priv = obj->dev->dev_private;
 198 
 199         if (omap_obj->flags & OMAP_BO_TILED) {
 200                 enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
 201                 int i;
 202 
 203                 for (i = 0; i < NUM_USERGART_ENTRIES; i++) {
 204                         struct omap_drm_usergart_entry *entry =
 205                                 &priv->usergart[fmt].entry[i];
 206 
 207                         if (entry->obj == obj)
 208                                 omap_gem_evict_entry(obj, fmt, entry);
 209                 }
 210         }
 211 }
 212 
 213 /* -----------------------------------------------------------------------------
 214  * Page Management
 215  */
 216 
 217 /*
 218  * Ensure backing pages are allocated. Must be called with the omap_obj.lock
 219  * held.
 220  */
 221 static int omap_gem_attach_pages(struct drm_gem_object *obj)
 222 {
 223         struct drm_device *dev = obj->dev;
 224         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 225         struct page **pages;
 226         int npages = obj->size >> PAGE_SHIFT;
 227         int i, ret;
 228         dma_addr_t *addrs;
 229 
 230         lockdep_assert_held(&omap_obj->lock);
 231 
 232         /*
 233          * If not using shmem (in which case backing pages don't need to be
 234          * allocated) or if pages are already allocated we're done.
 235          */
 236         if (!(omap_obj->flags & OMAP_BO_MEM_SHMEM) || omap_obj->pages)
 237                 return 0;
 238 
 239         pages = drm_gem_get_pages(obj);
 240         if (IS_ERR(pages)) {
 241                 dev_err(obj->dev->dev, "could not get pages: %ld\n", PTR_ERR(pages));
 242                 return PTR_ERR(pages);
 243         }
 244 
 245         /* for non-cached buffers, ensure the new pages are clean because
 246          * DSS, GPU, etc. are not cache coherent:
 247          */
 248         if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
 249                 addrs = kmalloc_array(npages, sizeof(*addrs), GFP_KERNEL);
 250                 if (!addrs) {
 251                         ret = -ENOMEM;
 252                         goto free_pages;
 253                 }
 254 
 255                 for (i = 0; i < npages; i++) {
 256                         addrs[i] = dma_map_page(dev->dev, pages[i],
 257                                         0, PAGE_SIZE, DMA_TO_DEVICE);
 258 
 259                         if (dma_mapping_error(dev->dev, addrs[i])) {
 260                                 dev_warn(dev->dev,
 261                                         "%s: failed to map page\n", __func__);
 262 
 263                                 for (i = i - 1; i >= 0; --i) {
 264                                         dma_unmap_page(dev->dev, addrs[i],
 265                                                 PAGE_SIZE, DMA_TO_DEVICE);
 266                                 }
 267 
 268                                 ret = -ENOMEM;
 269                                 goto free_addrs;
 270                         }
 271                 }
 272         } else {
 273                 addrs = kcalloc(npages, sizeof(*addrs), GFP_KERNEL);
 274                 if (!addrs) {
 275                         ret = -ENOMEM;
 276                         goto free_pages;
 277                 }
 278         }
 279 
 280         omap_obj->dma_addrs = addrs;
 281         omap_obj->pages = pages;
 282 
 283         return 0;
 284 
 285 free_addrs:
 286         kfree(addrs);
 287 free_pages:
 288         drm_gem_put_pages(obj, pages, true, false);
 289 
 290         return ret;
 291 }
 292 
 293 /* Release backing pages. Must be called with the omap_obj.lock held. */
 294 static void omap_gem_detach_pages(struct drm_gem_object *obj)
 295 {
 296         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 297         unsigned int npages = obj->size >> PAGE_SHIFT;
 298         unsigned int i;
 299 
 300         lockdep_assert_held(&omap_obj->lock);
 301 
 302         for (i = 0; i < npages; i++) {
 303                 if (omap_obj->dma_addrs[i])
 304                         dma_unmap_page(obj->dev->dev, omap_obj->dma_addrs[i],
 305                                        PAGE_SIZE, DMA_TO_DEVICE);
 306         }
 307 
 308         kfree(omap_obj->dma_addrs);
 309         omap_obj->dma_addrs = NULL;
 310 
 311         drm_gem_put_pages(obj, omap_obj->pages, true, false);
 312         omap_obj->pages = NULL;
 313 }
 314 
 315 /* get buffer flags */
 316 u32 omap_gem_flags(struct drm_gem_object *obj)
 317 {
 318         return to_omap_bo(obj)->flags;
 319 }
 320 
 321 /** get mmap size */
 322 size_t omap_gem_mmap_size(struct drm_gem_object *obj)
 323 {
 324         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 325         size_t size = obj->size;
 326 
 327         if (omap_obj->flags & OMAP_BO_TILED) {
 328                 /* for tiled buffers, the virtual size has stride rounded up
 329                  * to 4kb.. (to hide the fact that row n+1 might start 16kb or
 330                  * 32kb later!).  But we don't back the entire buffer with
 331                  * pages, only the valid picture part.. so need to adjust for
 332                  * this in the size used to mmap and generate mmap offset
 333                  */
 334                 size = tiler_vsize(gem2fmt(omap_obj->flags),
 335                                 omap_obj->width, omap_obj->height);
 336         }
 337 
 338         return size;
 339 }
 340 
 341 /* -----------------------------------------------------------------------------
 342  * Fault Handling
 343  */
 344 
 345 /* Normal handling for the case of faulting in non-tiled buffers */
 346 static vm_fault_t omap_gem_fault_1d(struct drm_gem_object *obj,
 347                 struct vm_area_struct *vma, struct vm_fault *vmf)
 348 {
 349         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 350         unsigned long pfn;
 351         pgoff_t pgoff;
 352 
 353         /* We don't use vmf->pgoff since that has the fake offset: */
 354         pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
 355 
 356         if (omap_obj->pages) {
 357                 omap_gem_cpu_sync_page(obj, pgoff);
 358                 pfn = page_to_pfn(omap_obj->pages[pgoff]);
 359         } else {
 360                 BUG_ON(!omap_gem_is_contiguous(omap_obj));
 361                 pfn = (omap_obj->dma_addr >> PAGE_SHIFT) + pgoff;
 362         }
 363 
 364         VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
 365                         pfn, pfn << PAGE_SHIFT);
 366 
 367         return vmf_insert_mixed(vma, vmf->address,
 368                         __pfn_to_pfn_t(pfn, PFN_DEV));
 369 }
 370 
 371 /* Special handling for the case of faulting in 2d tiled buffers */
 372 static vm_fault_t omap_gem_fault_2d(struct drm_gem_object *obj,
 373                 struct vm_area_struct *vma, struct vm_fault *vmf)
 374 {
 375         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 376         struct omap_drm_private *priv = obj->dev->dev_private;
 377         struct omap_drm_usergart_entry *entry;
 378         enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
 379         struct page *pages[64];  /* XXX is this too much to have on stack? */
 380         unsigned long pfn;
 381         pgoff_t pgoff, base_pgoff;
 382         unsigned long vaddr;
 383         int i, err, slots;
 384         vm_fault_t ret = VM_FAULT_NOPAGE;
 385 
 386         /*
 387          * Note the height of the slot is also equal to the number of pages
 388          * that need to be mapped in to fill 4kb wide CPU page.  If the slot
 389          * height is 64, then 64 pages fill a 4kb wide by 64 row region.
 390          */
 391         const int n = priv->usergart[fmt].height;
 392         const int n_shift = priv->usergart[fmt].height_shift;
 393 
 394         /*
 395          * If buffer width in bytes > PAGE_SIZE then the virtual stride is
 396          * rounded up to next multiple of PAGE_SIZE.. this need to be taken
 397          * into account in some of the math, so figure out virtual stride
 398          * in pages
 399          */
 400         const int m = DIV_ROUND_UP(omap_obj->width << fmt, PAGE_SIZE);
 401 
 402         /* We don't use vmf->pgoff since that has the fake offset: */
 403         pgoff = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
 404 
 405         /*
 406          * Actual address we start mapping at is rounded down to previous slot
 407          * boundary in the y direction:
 408          */
 409         base_pgoff = round_down(pgoff, m << n_shift);
 410 
 411         /* figure out buffer width in slots */
 412         slots = omap_obj->width >> priv->usergart[fmt].slot_shift;
 413 
 414         vaddr = vmf->address - ((pgoff - base_pgoff) << PAGE_SHIFT);
 415 
 416         entry = &priv->usergart[fmt].entry[priv->usergart[fmt].last];
 417 
 418         /* evict previous buffer using this usergart entry, if any: */
 419         if (entry->obj)
 420                 omap_gem_evict_entry(entry->obj, fmt, entry);
 421 
 422         entry->obj = obj;
 423         entry->obj_pgoff = base_pgoff;
 424 
 425         /* now convert base_pgoff to phys offset from virt offset: */
 426         base_pgoff = (base_pgoff >> n_shift) * slots;
 427 
 428         /* for wider-than 4k.. figure out which part of the slot-row we want: */
 429         if (m > 1) {
 430                 int off = pgoff % m;
 431                 entry->obj_pgoff += off;
 432                 base_pgoff /= m;
 433                 slots = min(slots - (off << n_shift), n);
 434                 base_pgoff += off << n_shift;
 435                 vaddr += off << PAGE_SHIFT;
 436         }
 437 
 438         /*
 439          * Map in pages. Beyond the valid pixel part of the buffer, we set
 440          * pages[i] to NULL to get a dummy page mapped in.. if someone
 441          * reads/writes it they will get random/undefined content, but at
 442          * least it won't be corrupting whatever other random page used to
 443          * be mapped in, or other undefined behavior.
 444          */
 445         memcpy(pages, &omap_obj->pages[base_pgoff],
 446                         sizeof(struct page *) * slots);
 447         memset(pages + slots, 0,
 448                         sizeof(struct page *) * (n - slots));
 449 
 450         err = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);
 451         if (err) {
 452                 ret = vmf_error(err);
 453                 dev_err(obj->dev->dev, "failed to pin: %d\n", err);
 454                 return ret;
 455         }
 456 
 457         pfn = entry->dma_addr >> PAGE_SHIFT;
 458 
 459         VERB("Inserting %p pfn %lx, pa %lx", (void *)vmf->address,
 460                         pfn, pfn << PAGE_SHIFT);
 461 
 462         for (i = n; i > 0; i--) {
 463                 ret = vmf_insert_mixed(vma,
 464                         vaddr, __pfn_to_pfn_t(pfn, PFN_DEV));
 465                 if (ret & VM_FAULT_ERROR)
 466                         break;
 467                 pfn += priv->usergart[fmt].stride_pfn;
 468                 vaddr += PAGE_SIZE * m;
 469         }
 470 
 471         /* simple round-robin: */
 472         priv->usergart[fmt].last = (priv->usergart[fmt].last + 1)
 473                                  % NUM_USERGART_ENTRIES;
 474 
 475         return ret;
 476 }
 477 
 478 /**
 479  * omap_gem_fault               -       pagefault handler for GEM objects
 480  * @vmf: fault detail
 481  *
 482  * Invoked when a fault occurs on an mmap of a GEM managed area. GEM
 483  * does most of the work for us including the actual map/unmap calls
 484  * but we need to do the actual page work.
 485  *
 486  * The VMA was set up by GEM. In doing so it also ensured that the
 487  * vma->vm_private_data points to the GEM object that is backing this
 488  * mapping.
 489  */
 490 vm_fault_t omap_gem_fault(struct vm_fault *vmf)
 491 {
 492         struct vm_area_struct *vma = vmf->vma;
 493         struct drm_gem_object *obj = vma->vm_private_data;
 494         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 495         int err;
 496         vm_fault_t ret;
 497 
 498         /* Make sure we don't parallel update on a fault, nor move or remove
 499          * something from beneath our feet
 500          */
 501         mutex_lock(&omap_obj->lock);
 502 
 503         /* if a shmem backed object, make sure we have pages attached now */
 504         err = omap_gem_attach_pages(obj);
 505         if (err) {
 506                 ret = vmf_error(err);
 507                 goto fail;
 508         }
 509 
 510         /* where should we do corresponding put_pages().. we are mapping
 511          * the original page, rather than thru a GART, so we can't rely
 512          * on eviction to trigger this.  But munmap() or all mappings should
 513          * probably trigger put_pages()?
 514          */
 515 
 516         if (omap_obj->flags & OMAP_BO_TILED)
 517                 ret = omap_gem_fault_2d(obj, vma, vmf);
 518         else
 519                 ret = omap_gem_fault_1d(obj, vma, vmf);
 520 
 521 
 522 fail:
 523         mutex_unlock(&omap_obj->lock);
 524         return ret;
 525 }
 526 
 527 /** We override mainly to fix up some of the vm mapping flags.. */
 528 int omap_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 529 {
 530         int ret;
 531 
 532         ret = drm_gem_mmap(filp, vma);
 533         if (ret) {
 534                 DBG("mmap failed: %d", ret);
 535                 return ret;
 536         }
 537 
 538         return omap_gem_mmap_obj(vma->vm_private_data, vma);
 539 }
 540 
 541 int omap_gem_mmap_obj(struct drm_gem_object *obj,
 542                 struct vm_area_struct *vma)
 543 {
 544         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 545 
 546         vma->vm_flags &= ~VM_PFNMAP;
 547         vma->vm_flags |= VM_MIXEDMAP;
 548 
 549         if (omap_obj->flags & OMAP_BO_WC) {
 550                 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 551         } else if (omap_obj->flags & OMAP_BO_UNCACHED) {
 552                 vma->vm_page_prot = pgprot_noncached(vm_get_page_prot(vma->vm_flags));
 553         } else {
 554                 /*
 555                  * We do have some private objects, at least for scanout buffers
 556                  * on hardware without DMM/TILER.  But these are allocated write-
 557                  * combine
 558                  */
 559                 if (WARN_ON(!obj->filp))
 560                         return -EINVAL;
 561 
 562                 /*
 563                  * Shunt off cached objs to shmem file so they have their own
 564                  * address_space (so unmap_mapping_range does what we want,
 565                  * in particular in the case of mmap'd dmabufs)
 566                  */
 567                 fput(vma->vm_file);
 568                 vma->vm_pgoff = 0;
 569                 vma->vm_file  = get_file(obj->filp);
 570 
 571                 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 572         }
 573 
 574         return 0;
 575 }
 576 
 577 /* -----------------------------------------------------------------------------
 578  * Dumb Buffers
 579  */
 580 
 581 /**
 582  * omap_gem_dumb_create -       create a dumb buffer
 583  * @drm_file: our client file
 584  * @dev: our device
 585  * @args: the requested arguments copied from userspace
 586  *
 587  * Allocate a buffer suitable for use for a frame buffer of the
 588  * form described by user space. Give userspace a handle by which
 589  * to reference it.
 590  */
 591 int omap_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
 592                 struct drm_mode_create_dumb *args)
 593 {
 594         union omap_gem_size gsize;
 595 
 596         args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
 597 
 598         args->size = PAGE_ALIGN(args->pitch * args->height);
 599 
 600         gsize = (union omap_gem_size){
 601                 .bytes = args->size,
 602         };
 603 
 604         return omap_gem_new_handle(dev, file, gsize,
 605                         OMAP_BO_SCANOUT | OMAP_BO_WC, &args->handle);
 606 }
 607 
 608 /**
 609  * omap_gem_dumb_map    -       buffer mapping for dumb interface
 610  * @file: our drm client file
 611  * @dev: drm device
 612  * @handle: GEM handle to the object (from dumb_create)
 613  *
 614  * Do the necessary setup to allow the mapping of the frame buffer
 615  * into user memory. We don't have to do much here at the moment.
 616  */
 617 int omap_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
 618                 u32 handle, u64 *offset)
 619 {
 620         struct drm_gem_object *obj;
 621         int ret = 0;
 622 
 623         /* GEM does all our handle to object mapping */
 624         obj = drm_gem_object_lookup(file, handle);
 625         if (obj == NULL) {
 626                 ret = -ENOENT;
 627                 goto fail;
 628         }
 629 
 630         *offset = omap_gem_mmap_offset(obj);
 631 
 632         drm_gem_object_put_unlocked(obj);
 633 
 634 fail:
 635         return ret;
 636 }
 637 
 638 #ifdef CONFIG_DRM_FBDEV_EMULATION
 639 /* Set scrolling position.  This allows us to implement fast scrolling
 640  * for console.
 641  *
 642  * Call only from non-atomic contexts.
 643  */
 644 int omap_gem_roll(struct drm_gem_object *obj, u32 roll)
 645 {
 646         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 647         u32 npages = obj->size >> PAGE_SHIFT;
 648         int ret = 0;
 649 
 650         if (roll > npages) {
 651                 dev_err(obj->dev->dev, "invalid roll: %d\n", roll);
 652                 return -EINVAL;
 653         }
 654 
 655         omap_obj->roll = roll;
 656 
 657         mutex_lock(&omap_obj->lock);
 658 
 659         /* if we aren't mapped yet, we don't need to do anything */
 660         if (omap_obj->block) {
 661                 ret = omap_gem_attach_pages(obj);
 662                 if (ret)
 663                         goto fail;
 664 
 665                 ret = tiler_pin(omap_obj->block, omap_obj->pages, npages,
 666                                 roll, true);
 667                 if (ret)
 668                         dev_err(obj->dev->dev, "could not repin: %d\n", ret);
 669         }
 670 
 671 fail:
 672         mutex_unlock(&omap_obj->lock);
 673 
 674         return ret;
 675 }
 676 #endif
 677 
 678 /* -----------------------------------------------------------------------------
 679  * Memory Management & DMA Sync
 680  */
 681 
 682 /*
 683  * shmem buffers that are mapped cached are not coherent.
 684  *
 685  * We keep track of dirty pages using page faulting to perform cache management.
 686  * When a page is mapped to the CPU in read/write mode the device can't access
 687  * it and omap_obj->dma_addrs[i] is NULL. When a page is mapped to the device
 688  * the omap_obj->dma_addrs[i] is set to the DMA address, and the page is
 689  * unmapped from the CPU.
 690  */
 691 static inline bool omap_gem_is_cached_coherent(struct drm_gem_object *obj)
 692 {
 693         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 694 
 695         return !((omap_obj->flags & OMAP_BO_MEM_SHMEM) &&
 696                 ((omap_obj->flags & OMAP_BO_CACHE_MASK) == OMAP_BO_CACHED));
 697 }
 698 
 699 /* Sync the buffer for CPU access.. note pages should already be
 700  * attached, ie. omap_gem_get_pages()
 701  */
 702 void omap_gem_cpu_sync_page(struct drm_gem_object *obj, int pgoff)
 703 {
 704         struct drm_device *dev = obj->dev;
 705         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 706 
 707         if (omap_gem_is_cached_coherent(obj))
 708                 return;
 709 
 710         if (omap_obj->dma_addrs[pgoff]) {
 711                 dma_unmap_page(dev->dev, omap_obj->dma_addrs[pgoff],
 712                                 PAGE_SIZE, DMA_TO_DEVICE);
 713                 omap_obj->dma_addrs[pgoff] = 0;
 714         }
 715 }
 716 
 717 /* sync the buffer for DMA access */
 718 void omap_gem_dma_sync_buffer(struct drm_gem_object *obj,
 719                 enum dma_data_direction dir)
 720 {
 721         struct drm_device *dev = obj->dev;
 722         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 723         int i, npages = obj->size >> PAGE_SHIFT;
 724         struct page **pages = omap_obj->pages;
 725         bool dirty = false;
 726 
 727         if (omap_gem_is_cached_coherent(obj))
 728                 return;
 729 
 730         for (i = 0; i < npages; i++) {
 731                 if (!omap_obj->dma_addrs[i]) {
 732                         dma_addr_t addr;
 733 
 734                         addr = dma_map_page(dev->dev, pages[i], 0,
 735                                             PAGE_SIZE, dir);
 736                         if (dma_mapping_error(dev->dev, addr)) {
 737                                 dev_warn(dev->dev, "%s: failed to map page\n",
 738                                         __func__);
 739                                 break;
 740                         }
 741 
 742                         dirty = true;
 743                         omap_obj->dma_addrs[i] = addr;
 744                 }
 745         }
 746 
 747         if (dirty) {
 748                 unmap_mapping_range(obj->filp->f_mapping, 0,
 749                                     omap_gem_mmap_size(obj), 1);
 750         }
 751 }
 752 
 753 /**
 754  * omap_gem_pin() - Pin a GEM object in memory
 755  * @obj: the GEM object
 756  * @dma_addr: the DMA address
 757  *
 758  * Pin the given GEM object in memory and fill the dma_addr pointer with the
 759  * object's DMA address. If the buffer is not physically contiguous it will be
 760  * remapped through the TILER to provide a contiguous view.
 761  *
 762  * Pins are reference-counted, calling this function multiple times is allowed
 763  * as long the corresponding omap_gem_unpin() calls are balanced.
 764  *
 765  * Return 0 on success or a negative error code otherwise.
 766  */
 767 int omap_gem_pin(struct drm_gem_object *obj, dma_addr_t *dma_addr)
 768 {
 769         struct omap_drm_private *priv = obj->dev->dev_private;
 770         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 771         int ret = 0;
 772 
 773         mutex_lock(&omap_obj->lock);
 774 
 775         if (!omap_gem_is_contiguous(omap_obj) && priv->has_dmm) {
 776                 if (omap_obj->dma_addr_cnt == 0) {
 777                         u32 npages = obj->size >> PAGE_SHIFT;
 778                         enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
 779                         struct tiler_block *block;
 780 
 781                         BUG_ON(omap_obj->block);
 782 
 783                         ret = omap_gem_attach_pages(obj);
 784                         if (ret)
 785                                 goto fail;
 786 
 787                         if (omap_obj->flags & OMAP_BO_TILED) {
 788                                 block = tiler_reserve_2d(fmt,
 789                                                 omap_obj->width,
 790                                                 omap_obj->height, 0);
 791                         } else {
 792                                 block = tiler_reserve_1d(obj->size);
 793                         }
 794 
 795                         if (IS_ERR(block)) {
 796                                 ret = PTR_ERR(block);
 797                                 dev_err(obj->dev->dev,
 798                                         "could not remap: %d (%d)\n", ret, fmt);
 799                                 goto fail;
 800                         }
 801 
 802                         /* TODO: enable async refill.. */
 803                         ret = tiler_pin(block, omap_obj->pages, npages,
 804                                         omap_obj->roll, true);
 805                         if (ret) {
 806                                 tiler_release(block);
 807                                 dev_err(obj->dev->dev,
 808                                                 "could not pin: %d\n", ret);
 809                                 goto fail;
 810                         }
 811 
 812                         omap_obj->dma_addr = tiler_ssptr(block);
 813                         omap_obj->block = block;
 814 
 815                         DBG("got dma address: %pad", &omap_obj->dma_addr);
 816                 }
 817 
 818                 omap_obj->dma_addr_cnt++;
 819 
 820                 *dma_addr = omap_obj->dma_addr;
 821         } else if (omap_gem_is_contiguous(omap_obj)) {
 822                 *dma_addr = omap_obj->dma_addr;
 823         } else {
 824                 ret = -EINVAL;
 825                 goto fail;
 826         }
 827 
 828 fail:
 829         mutex_unlock(&omap_obj->lock);
 830 
 831         return ret;
 832 }
 833 
 834 /**
 835  * omap_gem_unpin() - Unpin a GEM object from memory
 836  * @obj: the GEM object
 837  *
 838  * Unpin the given GEM object previously pinned with omap_gem_pin(). Pins are
 839  * reference-counted, the actualy unpin will only be performed when the number
 840  * of calls to this function matches the number of calls to omap_gem_pin().
 841  */
 842 void omap_gem_unpin(struct drm_gem_object *obj)
 843 {
 844         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 845         int ret;
 846 
 847         mutex_lock(&omap_obj->lock);
 848 
 849         if (omap_obj->dma_addr_cnt > 0) {
 850                 omap_obj->dma_addr_cnt--;
 851                 if (omap_obj->dma_addr_cnt == 0) {
 852                         ret = tiler_unpin(omap_obj->block);
 853                         if (ret) {
 854                                 dev_err(obj->dev->dev,
 855                                         "could not unpin pages: %d\n", ret);
 856                         }
 857                         ret = tiler_release(omap_obj->block);
 858                         if (ret) {
 859                                 dev_err(obj->dev->dev,
 860                                         "could not release unmap: %d\n", ret);
 861                         }
 862                         omap_obj->dma_addr = 0;
 863                         omap_obj->block = NULL;
 864                 }
 865         }
 866 
 867         mutex_unlock(&omap_obj->lock);
 868 }
 869 
 870 /* Get rotated scanout address (only valid if already pinned), at the
 871  * specified orientation and x,y offset from top-left corner of buffer
 872  * (only valid for tiled 2d buffers)
 873  */
 874 int omap_gem_rotated_dma_addr(struct drm_gem_object *obj, u32 orient,
 875                 int x, int y, dma_addr_t *dma_addr)
 876 {
 877         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 878         int ret = -EINVAL;
 879 
 880         mutex_lock(&omap_obj->lock);
 881 
 882         if ((omap_obj->dma_addr_cnt > 0) && omap_obj->block &&
 883                         (omap_obj->flags & OMAP_BO_TILED)) {
 884                 *dma_addr = tiler_tsptr(omap_obj->block, orient, x, y);
 885                 ret = 0;
 886         }
 887 
 888         mutex_unlock(&omap_obj->lock);
 889 
 890         return ret;
 891 }
 892 
 893 /* Get tiler stride for the buffer (only valid for 2d tiled buffers) */
 894 int omap_gem_tiled_stride(struct drm_gem_object *obj, u32 orient)
 895 {
 896         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 897         int ret = -EINVAL;
 898         if (omap_obj->flags & OMAP_BO_TILED)
 899                 ret = tiler_stride(gem2fmt(omap_obj->flags), orient);
 900         return ret;
 901 }
 902 
 903 /* if !remap, and we don't have pages backing, then fail, rather than
 904  * increasing the pin count (which we don't really do yet anyways,
 905  * because we don't support swapping pages back out).  And 'remap'
 906  * might not be quite the right name, but I wanted to keep it working
 907  * similarly to omap_gem_pin().  Note though that mutex is not
 908  * aquired if !remap (because this can be called in atomic ctxt),
 909  * but probably omap_gem_unpin() should be changed to work in the
 910  * same way.  If !remap, a matching omap_gem_put_pages() call is not
 911  * required (and should not be made).
 912  */
 913 int omap_gem_get_pages(struct drm_gem_object *obj, struct page ***pages,
 914                 bool remap)
 915 {
 916         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 917         int ret = 0;
 918 
 919         mutex_lock(&omap_obj->lock);
 920 
 921         if (remap) {
 922                 ret = omap_gem_attach_pages(obj);
 923                 if (ret)
 924                         goto unlock;
 925         }
 926 
 927         if (!omap_obj->pages) {
 928                 ret = -ENOMEM;
 929                 goto unlock;
 930         }
 931 
 932         *pages = omap_obj->pages;
 933 
 934 unlock:
 935         mutex_unlock(&omap_obj->lock);
 936 
 937         return ret;
 938 }
 939 
 940 /* release pages when DMA no longer being performed */
 941 int omap_gem_put_pages(struct drm_gem_object *obj)
 942 {
 943         /* do something here if we dynamically attach/detach pages.. at
 944          * least they would no longer need to be pinned if everyone has
 945          * released the pages..
 946          */
 947         return 0;
 948 }
 949 
 950 #ifdef CONFIG_DRM_FBDEV_EMULATION
 951 /*
 952  * Get kernel virtual address for CPU access.. this more or less only
 953  * exists for omap_fbdev.
 954  */
 955 void *omap_gem_vaddr(struct drm_gem_object *obj)
 956 {
 957         struct omap_gem_object *omap_obj = to_omap_bo(obj);
 958         void *vaddr;
 959         int ret;
 960 
 961         mutex_lock(&omap_obj->lock);
 962 
 963         if (!omap_obj->vaddr) {
 964                 ret = omap_gem_attach_pages(obj);
 965                 if (ret) {
 966                         vaddr = ERR_PTR(ret);
 967                         goto unlock;
 968                 }
 969 
 970                 omap_obj->vaddr = vmap(omap_obj->pages, obj->size >> PAGE_SHIFT,
 971                                 VM_MAP, pgprot_writecombine(PAGE_KERNEL));
 972         }
 973 
 974         vaddr = omap_obj->vaddr;
 975 
 976 unlock:
 977         mutex_unlock(&omap_obj->lock);
 978         return vaddr;
 979 }
 980 #endif
 981 
 982 /* -----------------------------------------------------------------------------
 983  * Power Management
 984  */
 985 
 986 #ifdef CONFIG_PM
 987 /* re-pin objects in DMM in resume path: */
 988 int omap_gem_resume(struct drm_device *dev)
 989 {
 990         struct omap_drm_private *priv = dev->dev_private;
 991         struct omap_gem_object *omap_obj;
 992         int ret = 0;
 993 
 994         mutex_lock(&priv->list_lock);
 995         list_for_each_entry(omap_obj, &priv->obj_list, mm_list) {
 996                 if (omap_obj->block) {
 997                         struct drm_gem_object *obj = &omap_obj->base;
 998                         u32 npages = obj->size >> PAGE_SHIFT;
 999 
1000                         WARN_ON(!omap_obj->pages);  /* this can't happen */
1001                         ret = tiler_pin(omap_obj->block,
1002                                         omap_obj->pages, npages,
1003                                         omap_obj->roll, true);
1004                         if (ret) {
1005                                 dev_err(dev->dev, "could not repin: %d\n", ret);
1006                                 goto done;
1007                         }
1008                 }
1009         }
1010 
1011 done:
1012         mutex_unlock(&priv->list_lock);
1013         return ret;
1014 }
1015 #endif
1016 
1017 /* -----------------------------------------------------------------------------
1018  * DebugFS
1019  */
1020 
1021 #ifdef CONFIG_DEBUG_FS
1022 void omap_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
1023 {
1024         struct omap_gem_object *omap_obj = to_omap_bo(obj);
1025         u64 off;
1026 
1027         off = drm_vma_node_start(&obj->vma_node);
1028 
1029         mutex_lock(&omap_obj->lock);
1030 
1031         seq_printf(m, "%08x: %2d (%2d) %08llx %pad (%2d) %p %4d",
1032                         omap_obj->flags, obj->name, kref_read(&obj->refcount),
1033                         off, &omap_obj->dma_addr, omap_obj->dma_addr_cnt,
1034                         omap_obj->vaddr, omap_obj->roll);
1035 
1036         if (omap_obj->flags & OMAP_BO_TILED) {
1037                 seq_printf(m, " %dx%d", omap_obj->width, omap_obj->height);
1038                 if (omap_obj->block) {
1039                         struct tcm_area *area = &omap_obj->block->area;
1040                         seq_printf(m, " (%dx%d, %dx%d)",
1041                                         area->p0.x, area->p0.y,
1042                                         area->p1.x, area->p1.y);
1043                 }
1044         } else {
1045                 seq_printf(m, " %zu", obj->size);
1046         }
1047 
1048         mutex_unlock(&omap_obj->lock);
1049 
1050         seq_printf(m, "\n");
1051 }
1052 
1053 void omap_gem_describe_objects(struct list_head *list, struct seq_file *m)
1054 {
1055         struct omap_gem_object *omap_obj;
1056         int count = 0;
1057         size_t size = 0;
1058 
1059         list_for_each_entry(omap_obj, list, mm_list) {
1060                 struct drm_gem_object *obj = &omap_obj->base;
1061                 seq_printf(m, "   ");
1062                 omap_gem_describe(obj, m);
1063                 count++;
1064                 size += obj->size;
1065         }
1066 
1067         seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
1068 }
1069 #endif
1070 
1071 /* -----------------------------------------------------------------------------
1072  * Constructor & Destructor
1073  */
1074 
1075 void omap_gem_free_object(struct drm_gem_object *obj)
1076 {
1077         struct drm_device *dev = obj->dev;
1078         struct omap_drm_private *priv = dev->dev_private;
1079         struct omap_gem_object *omap_obj = to_omap_bo(obj);
1080 
1081         omap_gem_evict(obj);
1082 
1083         mutex_lock(&priv->list_lock);
1084         list_del(&omap_obj->mm_list);
1085         mutex_unlock(&priv->list_lock);
1086 
1087         /*
1088          * We own the sole reference to the object at this point, but to keep
1089          * lockdep happy, we must still take the omap_obj_lock to call
1090          * omap_gem_detach_pages(). This should hardly make any difference as
1091          * there can't be any lock contention.
1092          */
1093         mutex_lock(&omap_obj->lock);
1094 
1095         /* The object should not be pinned. */
1096         WARN_ON(omap_obj->dma_addr_cnt > 0);
1097 
1098         if (omap_obj->pages) {
1099                 if (omap_obj->flags & OMAP_BO_MEM_DMABUF)
1100                         kfree(omap_obj->pages);
1101                 else
1102                         omap_gem_detach_pages(obj);
1103         }
1104 
1105         if (omap_obj->flags & OMAP_BO_MEM_DMA_API) {
1106                 dma_free_wc(dev->dev, obj->size, omap_obj->vaddr,
1107                             omap_obj->dma_addr);
1108         } else if (omap_obj->vaddr) {
1109                 vunmap(omap_obj->vaddr);
1110         } else if (obj->import_attach) {
1111                 drm_prime_gem_destroy(obj, omap_obj->sgt);
1112         }
1113 
1114         mutex_unlock(&omap_obj->lock);
1115 
1116         drm_gem_object_release(obj);
1117 
1118         mutex_destroy(&omap_obj->lock);
1119 
1120         kfree(omap_obj);
1121 }
1122 
1123 /* GEM buffer object constructor */
1124 struct drm_gem_object *omap_gem_new(struct drm_device *dev,
1125                 union omap_gem_size gsize, u32 flags)
1126 {
1127         struct omap_drm_private *priv = dev->dev_private;
1128         struct omap_gem_object *omap_obj;
1129         struct drm_gem_object *obj;
1130         struct address_space *mapping;
1131         size_t size;
1132         int ret;
1133 
1134         /* Validate the flags and compute the memory and cache flags. */
1135         if (flags & OMAP_BO_TILED) {
1136                 if (!priv->usergart) {
1137                         dev_err(dev->dev, "Tiled buffers require DMM\n");
1138                         return NULL;
1139                 }
1140 
1141                 /*
1142                  * Tiled buffers are always shmem paged backed. When they are
1143                  * scanned out, they are remapped into DMM/TILER.
1144                  */
1145                 flags &= ~OMAP_BO_SCANOUT;
1146                 flags |= OMAP_BO_MEM_SHMEM;
1147 
1148                 /*
1149                  * Currently don't allow cached buffers. There is some caching
1150                  * stuff that needs to be handled better.
1151                  */
1152                 flags &= ~(OMAP_BO_CACHED|OMAP_BO_WC|OMAP_BO_UNCACHED);
1153                 flags |= tiler_get_cpu_cache_flags();
1154         } else if ((flags & OMAP_BO_SCANOUT) && !priv->has_dmm) {
1155                 /*
1156                  * OMAP_BO_SCANOUT hints that the buffer doesn't need to be
1157                  * tiled. However, to lower the pressure on memory allocation,
1158                  * use contiguous memory only if no TILER is available.
1159                  */
1160                 flags |= OMAP_BO_MEM_DMA_API;
1161         } else if (!(flags & OMAP_BO_MEM_DMABUF)) {
1162                 /*
1163                  * All other buffers not backed by dma_buf are shmem-backed.
1164                  */
1165                 flags |= OMAP_BO_MEM_SHMEM;
1166         }
1167 
1168         /* Allocate the initialize the OMAP GEM object. */
1169         omap_obj = kzalloc(sizeof(*omap_obj), GFP_KERNEL);
1170         if (!omap_obj)
1171                 return NULL;
1172 
1173         obj = &omap_obj->base;
1174         omap_obj->flags = flags;
1175         mutex_init(&omap_obj->lock);
1176 
1177         if (flags & OMAP_BO_TILED) {
1178                 /*
1179                  * For tiled buffers align dimensions to slot boundaries and
1180                  * calculate size based on aligned dimensions.
1181                  */
1182                 tiler_align(gem2fmt(flags), &gsize.tiled.width,
1183                             &gsize.tiled.height);
1184 
1185                 size = tiler_size(gem2fmt(flags), gsize.tiled.width,
1186                                   gsize.tiled.height);
1187 
1188                 omap_obj->width = gsize.tiled.width;
1189                 omap_obj->height = gsize.tiled.height;
1190         } else {
1191                 size = PAGE_ALIGN(gsize.bytes);
1192         }
1193 
1194         /* Initialize the GEM object. */
1195         if (!(flags & OMAP_BO_MEM_SHMEM)) {
1196                 drm_gem_private_object_init(dev, obj, size);
1197         } else {
1198                 ret = drm_gem_object_init(dev, obj, size);
1199                 if (ret)
1200                         goto err_free;
1201 
1202                 mapping = obj->filp->f_mapping;
1203                 mapping_set_gfp_mask(mapping, GFP_USER | __GFP_DMA32);
1204         }
1205 
1206         /* Allocate memory if needed. */
1207         if (flags & OMAP_BO_MEM_DMA_API) {
1208                 omap_obj->vaddr = dma_alloc_wc(dev->dev, size,
1209                                                &omap_obj->dma_addr,
1210                                                GFP_KERNEL);
1211                 if (!omap_obj->vaddr)
1212                         goto err_release;
1213         }
1214 
1215         mutex_lock(&priv->list_lock);
1216         list_add(&omap_obj->mm_list, &priv->obj_list);
1217         mutex_unlock(&priv->list_lock);
1218 
1219         return obj;
1220 
1221 err_release:
1222         drm_gem_object_release(obj);
1223 err_free:
1224         kfree(omap_obj);
1225         return NULL;
1226 }
1227 
1228 struct drm_gem_object *omap_gem_new_dmabuf(struct drm_device *dev, size_t size,
1229                                            struct sg_table *sgt)
1230 {
1231         struct omap_drm_private *priv = dev->dev_private;
1232         struct omap_gem_object *omap_obj;
1233         struct drm_gem_object *obj;
1234         union omap_gem_size gsize;
1235 
1236         /* Without a DMM only physically contiguous buffers can be supported. */
1237         if (sgt->orig_nents != 1 && !priv->has_dmm)
1238                 return ERR_PTR(-EINVAL);
1239 
1240         gsize.bytes = PAGE_ALIGN(size);
1241         obj = omap_gem_new(dev, gsize, OMAP_BO_MEM_DMABUF | OMAP_BO_WC);
1242         if (!obj)
1243                 return ERR_PTR(-ENOMEM);
1244 
1245         omap_obj = to_omap_bo(obj);
1246 
1247         mutex_lock(&omap_obj->lock);
1248 
1249         omap_obj->sgt = sgt;
1250 
1251         if (sgt->orig_nents == 1) {
1252                 omap_obj->dma_addr = sg_dma_address(sgt->sgl);
1253         } else {
1254                 /* Create pages list from sgt */
1255                 struct sg_page_iter iter;
1256                 struct page **pages;
1257                 unsigned int npages;
1258                 unsigned int i = 0;
1259 
1260                 npages = DIV_ROUND_UP(size, PAGE_SIZE);
1261                 pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
1262                 if (!pages) {
1263                         omap_gem_free_object(obj);
1264                         obj = ERR_PTR(-ENOMEM);
1265                         goto done;
1266                 }
1267 
1268                 omap_obj->pages = pages;
1269 
1270                 for_each_sg_page(sgt->sgl, &iter, sgt->orig_nents, 0) {
1271                         pages[i++] = sg_page_iter_page(&iter);
1272                         if (i > npages)
1273                                 break;
1274                 }
1275 
1276                 if (WARN_ON(i != npages)) {
1277                         omap_gem_free_object(obj);
1278                         obj = ERR_PTR(-ENOMEM);
1279                         goto done;
1280                 }
1281         }
1282 
1283 done:
1284         mutex_unlock(&omap_obj->lock);
1285         return obj;
1286 }
1287 
1288 /* convenience method to construct a GEM buffer object, and userspace handle */
1289 int omap_gem_new_handle(struct drm_device *dev, struct drm_file *file,
1290                 union omap_gem_size gsize, u32 flags, u32 *handle)
1291 {
1292         struct drm_gem_object *obj;
1293         int ret;
1294 
1295         obj = omap_gem_new(dev, gsize, flags);
1296         if (!obj)
1297                 return -ENOMEM;
1298 
1299         ret = drm_gem_handle_create(file, obj, handle);
1300         if (ret) {
1301                 omap_gem_free_object(obj);
1302                 return ret;
1303         }
1304 
1305         /* drop reference from allocate - handle holds it now */
1306         drm_gem_object_put_unlocked(obj);
1307 
1308         return 0;
1309 }
1310 
1311 /* -----------------------------------------------------------------------------
1312  * Init & Cleanup
1313  */
1314 
1315 /* If DMM is used, we need to set some stuff up.. */
1316 void omap_gem_init(struct drm_device *dev)
1317 {
1318         struct omap_drm_private *priv = dev->dev_private;
1319         struct omap_drm_usergart *usergart;
1320         const enum tiler_fmt fmts[] = {
1321                         TILFMT_8BIT, TILFMT_16BIT, TILFMT_32BIT
1322         };
1323         int i, j;
1324 
1325         if (!dmm_is_available()) {
1326                 /* DMM only supported on OMAP4 and later, so this isn't fatal */
1327                 dev_warn(dev->dev, "DMM not available, disable DMM support\n");
1328                 return;
1329         }
1330 
1331         usergart = kcalloc(3, sizeof(*usergart), GFP_KERNEL);
1332         if (!usergart)
1333                 return;
1334 
1335         /* reserve 4k aligned/wide regions for userspace mappings: */
1336         for (i = 0; i < ARRAY_SIZE(fmts); i++) {
1337                 u16 h = 1, w = PAGE_SIZE >> i;
1338 
1339                 tiler_align(fmts[i], &w, &h);
1340                 /* note: since each region is 1 4kb page wide, and minimum
1341                  * number of rows, the height ends up being the same as the
1342                  * # of pages in the region
1343                  */
1344                 usergart[i].height = h;
1345                 usergart[i].height_shift = ilog2(h);
1346                 usergart[i].stride_pfn = tiler_stride(fmts[i], 0) >> PAGE_SHIFT;
1347                 usergart[i].slot_shift = ilog2((PAGE_SIZE / h) >> i);
1348                 for (j = 0; j < NUM_USERGART_ENTRIES; j++) {
1349                         struct omap_drm_usergart_entry *entry;
1350                         struct tiler_block *block;
1351 
1352                         entry = &usergart[i].entry[j];
1353                         block = tiler_reserve_2d(fmts[i], w, h, PAGE_SIZE);
1354                         if (IS_ERR(block)) {
1355                                 dev_err(dev->dev,
1356                                                 "reserve failed: %d, %d, %ld\n",
1357                                                 i, j, PTR_ERR(block));
1358                                 return;
1359                         }
1360                         entry->dma_addr = tiler_ssptr(block);
1361                         entry->block = block;
1362 
1363                         DBG("%d:%d: %dx%d: dma_addr=%pad stride=%d", i, j, w, h,
1364                                         &entry->dma_addr,
1365                                         usergart[i].stride_pfn << PAGE_SHIFT);
1366                 }
1367         }
1368 
1369         priv->usergart = usergart;
1370         priv->has_dmm = true;
1371 }
1372 
1373 void omap_gem_deinit(struct drm_device *dev)
1374 {
1375         struct omap_drm_private *priv = dev->dev_private;
1376 
1377         /* I believe we can rely on there being no more outstanding GEM
1378          * objects which could depend on usergart/dmm at this point.
1379          */
1380         kfree(priv->usergart);
1381 }