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 	if (WARN_ON(!is_power_of_2(size)))
27 		return ERR_PTR(-EINVAL);
28 
29 	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
30 	if (!ring) {
31 		ret = -ENOMEM;
32 		goto fail;
33 	}
34 
35 	ring->gpu = gpu;
36 
37 	/* Pass NULL for the iova pointer - we will map it later */
38 	ring->start = msm_gem_kernel_new(gpu->dev, size, MSM_BO_WC,
39 		gpu->aspace, &ring->bo, NULL);
40 
41 	if (IS_ERR(ring->start)) {
42 		ret = PTR_ERR(ring->start);
43 		ring->start = 0;
44 		goto fail;
45 	}
46 	ring->end   = ring->start + (size / 4);
47 	ring->cur   = ring->start;
48 
49 	ring->size = size;
50 
51 	return ring;
52 
53 fail:
54 	if (ring)
55 		msm_ringbuffer_destroy(ring);
56 	return ERR_PTR(ret);
57 }
58 
59 void msm_ringbuffer_destroy(struct msm_ringbuffer *ring)
60 {
61 	if (ring->bo) {
62 		msm_gem_put_vaddr(ring->bo);
63 		drm_gem_object_unreference_unlocked(ring->bo);
64 	}
65 	kfree(ring);
66 }
67