1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2013-2016 Red Hat
4 * Author: Rob Clark <robdclark@gmail.com>
5 */
6
7 #include <linux/dma-fence.h>
8
9 #include "msm_drv.h"
10 #include "msm_fence.h"
11
12
13 struct msm_fence_context *
msm_fence_context_alloc(struct drm_device * dev,volatile uint32_t * fenceptr,const char * name)14 msm_fence_context_alloc(struct drm_device *dev, volatile uint32_t *fenceptr,
15 const char *name)
16 {
17 struct msm_fence_context *fctx;
18 static int index = 0;
19
20 fctx = kzalloc(sizeof(*fctx), GFP_KERNEL);
21 if (!fctx)
22 return ERR_PTR(-ENOMEM);
23
24 fctx->dev = dev;
25 strscpy(fctx->name, name, sizeof(fctx->name));
26 fctx->context = dma_fence_context_alloc(1);
27 fctx->index = index++;
28 fctx->fenceptr = fenceptr;
29 spin_lock_init(&fctx->spinlock);
30
31 /*
32 * Start out close to the 32b fence rollover point, so we can
33 * catch bugs with fence comparisons.
34 */
35 fctx->last_fence = 0xffffff00;
36 fctx->completed_fence = fctx->last_fence;
37 *fctx->fenceptr = fctx->last_fence;
38
39 return fctx;
40 }
41
msm_fence_context_free(struct msm_fence_context * fctx)42 void msm_fence_context_free(struct msm_fence_context *fctx)
43 {
44 kfree(fctx);
45 }
46
msm_fence_completed(struct msm_fence_context * fctx,uint32_t fence)47 bool msm_fence_completed(struct msm_fence_context *fctx, uint32_t fence)
48 {
49 /*
50 * Note: Check completed_fence first, as fenceptr is in a write-combine
51 * mapping, so it will be more expensive to read.
52 */
53 return (int32_t)(fctx->completed_fence - fence) >= 0 ||
54 (int32_t)(*fctx->fenceptr - fence) >= 0;
55 }
56
57 /* called from irq handler and workqueue (in recover path) */
msm_update_fence(struct msm_fence_context * fctx,uint32_t fence)58 void msm_update_fence(struct msm_fence_context *fctx, uint32_t fence)
59 {
60 unsigned long flags;
61
62 spin_lock_irqsave(&fctx->spinlock, flags);
63 if (fence_after(fence, fctx->completed_fence))
64 fctx->completed_fence = fence;
65 spin_unlock_irqrestore(&fctx->spinlock, flags);
66 }
67
68 struct msm_fence {
69 struct dma_fence base;
70 struct msm_fence_context *fctx;
71 };
72
to_msm_fence(struct dma_fence * fence)73 static inline struct msm_fence *to_msm_fence(struct dma_fence *fence)
74 {
75 return container_of(fence, struct msm_fence, base);
76 }
77
msm_fence_get_driver_name(struct dma_fence * fence)78 static const char *msm_fence_get_driver_name(struct dma_fence *fence)
79 {
80 return "msm";
81 }
82
msm_fence_get_timeline_name(struct dma_fence * fence)83 static const char *msm_fence_get_timeline_name(struct dma_fence *fence)
84 {
85 struct msm_fence *f = to_msm_fence(fence);
86 return f->fctx->name;
87 }
88
msm_fence_signaled(struct dma_fence * fence)89 static bool msm_fence_signaled(struct dma_fence *fence)
90 {
91 struct msm_fence *f = to_msm_fence(fence);
92 return msm_fence_completed(f->fctx, f->base.seqno);
93 }
94
95 static const struct dma_fence_ops msm_fence_ops = {
96 .get_driver_name = msm_fence_get_driver_name,
97 .get_timeline_name = msm_fence_get_timeline_name,
98 .signaled = msm_fence_signaled,
99 };
100
101 struct dma_fence *
msm_fence_alloc(struct msm_fence_context * fctx)102 msm_fence_alloc(struct msm_fence_context *fctx)
103 {
104 struct msm_fence *f;
105
106 f = kzalloc(sizeof(*f), GFP_KERNEL);
107 if (!f)
108 return ERR_PTR(-ENOMEM);
109
110 f->fctx = fctx;
111
112 dma_fence_init(&f->base, &msm_fence_ops, &fctx->spinlock,
113 fctx->context, ++fctx->last_fence);
114
115 return &f->base;
116 }
117