include/drm/drm_writeback.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * (C) COPYRIGHT 2016 ARM Limited. All rights reserved.
   4  * Author: Brian Starkey <brian.starkey@arm.com>
   5  *
   6  * This program is free software and is provided to you under the terms of the
   7  * GNU General Public License version 2 as published by the Free Software
   8  * Foundation, and any use by you of this program is subject to the terms
   9  * of such GNU licence.
  10  */
  11
  12 #ifndef __DRM_WRITEBACK_H__
  13 #define __DRM_WRITEBACK_H__
  14 #include <drm/drm_connector.h>
  15 #include <drm/drm_encoder.h>
  16 #include <linux/workqueue.h>
  17
  18 struct drm_writeback_connector {
  19         struct drm_connector base;
  20
  21         /**
  22          * @encoder: Internal encoder used by the connector to fulfill
  23          * the DRM framework requirements. The users of the
  24          * @drm_writeback_connector control the behaviour of the @encoder
  25          * by passing the @enc_funcs parameter to drm_writeback_connector_init()
  26          * function.
  27          */
  28         struct drm_encoder encoder;
  29
  30         /**
  31          * @pixel_formats_blob_ptr:
  32          *
  33          * DRM blob property data for the pixel formats list on writeback
  34          * connectors
  35          * See also drm_writeback_connector_init()
  36          */
  37         struct drm_property_blob *pixel_formats_blob_ptr;
  38
  39         /** @job_lock: Protects job_queue */
  40         spinlock_t job_lock;
  41
  42         /**
  43          * @job_queue:
  44          *
  45          * Holds a list of a connector's writeback jobs; the last item is the
  46          * most recent. The first item may be either waiting for the hardware
  47          * to begin writing, or currently being written.
  48          *
  49          * See also: drm_writeback_queue_job() and
  50          * drm_writeback_signal_completion()
  51          */
  52         struct list_head job_queue;
  53
  54         /**
  55          * @fence_context:
  56          *
  57          * timeline context used for fence operations.
  58          */
  59         unsigned int fence_context;
  60         /**
  61          * @fence_lock:
  62          *
  63          * spinlock to protect the fences in the fence_context.
  64          */
  65         spinlock_t fence_lock;
  66         /**
  67          * @fence_seqno:
  68          *
  69          * Seqno variable used as monotonic counter for the fences
  70          * created on the connector's timeline.
  71          */
  72         unsigned long fence_seqno;
  73         /**
  74          * @timeline_name:
  75          *
  76          * The name of the connector's fence timeline.
  77          */
  78         char timeline_name[32];
  79 };
  80
  81 struct drm_writeback_job {
  82         /**
  83          * @cleanup_work:
  84          *
  85          * Used to allow drm_writeback_signal_completion to defer dropping the
  86          * framebuffer reference to a workqueue
  87          */
  88         struct work_struct cleanup_work;
  89
  90         /**
  91          * @list_entry:
  92          *
  93          * List item for the writeback connector's @job_queue
  94          */
  95         struct list_head list_entry;
  96
  97         /**
  98          * @fb:
  99          *
 100          * Framebuffer to be written to by the writeback connector. Do not set
 101          * directly, use drm_atomic_set_writeback_fb_for_connector()
 102          */
 103         struct drm_framebuffer *fb;
 104
 105         /**
 106          * @out_fence:
 107          *
 108          * Fence which will signal once the writeback has completed
 109          */
 110         struct dma_fence *out_fence;
 111 };
 112
 113 static inline struct drm_writeback_connector *
 114 drm_connector_to_writeback(struct drm_connector *connector)
 115 {
 116         return container_of(connector, struct drm_writeback_connector, base);
 117 }
 118
 119 int drm_writeback_connector_init(struct drm_device *dev,
 120                                  struct drm_writeback_connector *wb_connector,
 121                                  const struct drm_connector_funcs *con_funcs,
 122                                  const struct drm_encoder_helper_funcs *enc_helper_funcs,
 123                                  const u32 *formats, int n_formats);
 124
 125 void drm_writeback_queue_job(struct drm_writeback_connector *wb_connector,
 126                              struct drm_writeback_job *job);
 127
 128 void drm_writeback_cleanup_job(struct drm_writeback_job *job);
 129
 130 void
 131 drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector,
 132                                 int status);
 133
 134 struct dma_fence *
 135 drm_writeback_get_out_fence(struct drm_writeback_connector *wb_connector);
 136 #endif