Rob Clark | cabaafc | 2013-08-07 14:41:54 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2013 Red Hat |
| 3 | * |
| 4 | * Permission is hereby granted, free of charge, to any person obtaining a |
| 5 | * copy of this software and associated documentation files (the "Software"), |
| 6 | * to deal in the Software without restriction, including without limitation |
| 7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 8 | * and/or sell copies of the Software, and to permit persons to whom the |
| 9 | * Software is furnished to do so, subject to the following conditions: |
| 10 | * |
| 11 | * The above copyright notice and this permission notice (including the next |
| 12 | * paragraph) shall be included in all copies or substantial portions of the |
| 13 | * Software. |
| 14 | * |
| 15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 16 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 18 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 19 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 20 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 21 | * SOFTWARE. |
| 22 | */ |
| 23 | |
| 24 | #include "drmP.h" |
| 25 | #include "drm_flip_work.h" |
| 26 | |
| 27 | /** |
| 28 | * drm_flip_work_queue - queue work |
| 29 | * @work: the flip-work |
| 30 | * @val: the value to queue |
| 31 | * |
| 32 | * Queues work, that will later be run (passed back to drm_flip_func_t |
| 33 | * func) on a work queue after drm_flip_work_commit() is called. |
| 34 | */ |
| 35 | void drm_flip_work_queue(struct drm_flip_work *work, void *val) |
| 36 | { |
| 37 | if (kfifo_put(&work->fifo, (const void **)&val)) { |
| 38 | atomic_inc(&work->pending); |
| 39 | } else { |
| 40 | DRM_ERROR("%s fifo full!\n", work->name); |
| 41 | work->func(work, val); |
| 42 | } |
| 43 | } |
| 44 | EXPORT_SYMBOL(drm_flip_work_queue); |
| 45 | |
| 46 | /** |
| 47 | * drm_flip_work_commit - commit queued work |
| 48 | * @work: the flip-work |
| 49 | * @wq: the work-queue to run the queued work on |
| 50 | * |
| 51 | * Trigger work previously queued by drm_flip_work_queue() to run |
| 52 | * on a workqueue. The typical usage would be to queue work (via |
| 53 | * drm_flip_work_queue()) at any point (from vblank irq and/or |
| 54 | * prior), and then from vblank irq commit the queued work. |
| 55 | */ |
| 56 | void drm_flip_work_commit(struct drm_flip_work *work, |
| 57 | struct workqueue_struct *wq) |
| 58 | { |
| 59 | uint32_t pending = atomic_read(&work->pending); |
| 60 | atomic_add(pending, &work->count); |
| 61 | atomic_sub(pending, &work->pending); |
| 62 | queue_work(wq, &work->worker); |
| 63 | } |
| 64 | EXPORT_SYMBOL(drm_flip_work_commit); |
| 65 | |
| 66 | static void flip_worker(struct work_struct *w) |
| 67 | { |
| 68 | struct drm_flip_work *work = container_of(w, struct drm_flip_work, worker); |
| 69 | uint32_t count = atomic_read(&work->count); |
| 70 | void *val = NULL; |
| 71 | |
| 72 | atomic_sub(count, &work->count); |
| 73 | |
| 74 | while(count--) |
| 75 | if (!WARN_ON(!kfifo_get(&work->fifo, &val))) |
| 76 | work->func(work, val); |
| 77 | } |
| 78 | |
| 79 | /** |
| 80 | * drm_flip_work_init - initialize flip-work |
| 81 | * @work: the flip-work to initialize |
| 82 | * @size: the max queue depth |
| 83 | * @name: debug name |
| 84 | * @func: the callback work function |
| 85 | * |
| 86 | * Initializes/allocates resources for the flip-work |
| 87 | * |
| 88 | * RETURNS: |
| 89 | * Zero on success, error code on failure. |
| 90 | */ |
| 91 | int drm_flip_work_init(struct drm_flip_work *work, int size, |
| 92 | const char *name, drm_flip_func_t func) |
| 93 | { |
| 94 | int ret; |
| 95 | |
| 96 | work->name = name; |
| 97 | atomic_set(&work->count, 0); |
| 98 | atomic_set(&work->pending, 0); |
| 99 | work->func = func; |
| 100 | |
| 101 | ret = kfifo_alloc(&work->fifo, size, GFP_KERNEL); |
| 102 | if (ret) { |
| 103 | DRM_ERROR("could not allocate %s fifo\n", name); |
| 104 | return ret; |
| 105 | } |
| 106 | |
| 107 | INIT_WORK(&work->worker, flip_worker); |
| 108 | |
| 109 | return 0; |
| 110 | } |
| 111 | EXPORT_SYMBOL(drm_flip_work_init); |
| 112 | |
| 113 | /** |
| 114 | * drm_flip_work_cleanup - cleans up flip-work |
| 115 | * @work: the flip-work to cleanup |
| 116 | * |
| 117 | * Destroy resources allocated for the flip-work |
| 118 | */ |
| 119 | void drm_flip_work_cleanup(struct drm_flip_work *work) |
| 120 | { |
| 121 | WARN_ON(!kfifo_is_empty(&work->fifo)); |
| 122 | kfifo_free(&work->fifo); |
| 123 | } |
| 124 | EXPORT_SYMBOL(drm_flip_work_cleanup); |