drivers/gpu/drm/msm/msm_ringbuffer.c

   1 /*
   2  * Copyright (C) 2013 Red Hat
   3  * Author: Rob Clark <robdclark@gmail.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "msm_ringbuffer.h"
  19 #include "msm_gpu.h"
  20
  21 struct msm_ringbuffer *msm_ringbuffer_new(struct msm_gpu *gpu, int size)
  22 {
  23         struct msm_ringbuffer *ring;
  24         int ret;
  25
  26         size = ALIGN(size, 4);   /* size should be dword aligned */
  27
  28         ring = kzalloc(sizeof(*ring), GFP_KERNEL);
  29         if (!ring) {
  30                 ret = -ENOMEM;
  31                 goto fail;
  32         }
  33
  34         ring->gpu = gpu;
  35         ring->bo = msm_gem_new(gpu->dev, size, MSM_BO_WC);
  36         if (IS_ERR(ring->bo)) {
  37                 ret = PTR_ERR(ring->bo);
  38                 ring->bo = NULL;
  39                 goto fail;
  40         }
  41
  42         ring->start = msm_gem_vaddr_locked(ring->bo);
  43         ring->end   = ring->start + (size / 4);
  44         ring->cur   = ring->start;
  45
  46         ring->size = size;
  47
  48         return ring;
  49
  50 fail:
  51         if (ring)
  52                 msm_ringbuffer_destroy(ring);
  53         return ERR_PTR(ret);
  54 }
  55
  56 void msm_ringbuffer_destroy(struct msm_ringbuffer *ring)
  57 {
  58         if (ring->bo)
  59                 drm_gem_object_unreference(ring->bo);
  60         kfree(ring);
  61 }