drivers/gpu/drm/vc4/vc4_bo.c

   1 /*
   2  *  Copyright © 2015 Broadcom
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 /* DOC: VC4 GEM BO management support.
  10  *
  11  * The VC4 GPU architecture (both scanout and rendering) has direct
  12  * access to system memory with no MMU in between.  To support it, we
  13  * use the GEM CMA helper functions to allocate contiguous ranges of
  14  * physical memory for our BOs.
  15  */
  16
  17 #include "vc4_drv.h"
  18
  19 struct vc4_bo *vc4_bo_create(struct drm_device *dev, size_t size)
  20 {
  21         struct drm_gem_cma_object *cma_obj;
  22
  23         cma_obj = drm_gem_cma_create(dev, size);
  24         if (IS_ERR(cma_obj))
  25                 return NULL;
  26         else
  27                 return to_vc4_bo(&cma_obj->base);
  28 }
  29
  30 int vc4_dumb_create(struct drm_file *file_priv,
  31                     struct drm_device *dev,
  32                     struct drm_mode_create_dumb *args)
  33 {
  34         int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
  35         struct vc4_bo *bo = NULL;
  36         int ret;
  37
  38         if (args->pitch < min_pitch)
  39                 args->pitch = min_pitch;
  40
  41         if (args->size < args->pitch * args->height)
  42                 args->size = args->pitch * args->height;
  43
  44         bo = vc4_bo_create(dev, roundup(args->size, PAGE_SIZE));
  45         if (!bo)
  46                 return -ENOMEM;
  47
  48         ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
  49         drm_gem_object_unreference_unlocked(&bo->base.base);
  50
  51         return ret;
  52 }