drm/fence: add fence timeline to drm_crtc

Create one timeline context for each CRTC to be able to handle out-fences
and signal them. It adds a few members to struct drm_crtc: fence_context,
where we store the context we get from fence_context_alloc(), the
fence seqno and the fence lock, that we pass in fence_init() to be
used by the fence.

v2: Comment by Daniel Stone:
	- add BUG_ON() to fence_to_crtc() macro

v3: Comment by Ville Syrjälä
	- Use more meaningful name as crtc timeline name

v4: Comments by Brian Starkey
	- Use even more meaninful name for the crtc timeline
	- add doc for timeline_name
    Comment by Daniel Vetter
	- use in-line style for comments

    - rebase after fence -> dma_fence rename

v5: Comment by Daniel Vetter
	- Add doc for drm_crtc_fence_ops

v6: Comment by Chris Wilson
	- Move fence_to_crtc to drm_crtc.c
	- Move export of drm_crtc_fence_ops to drm_crtc_internal.h

    - rebase against latest drm-misc

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v5)
Reviewed-by: Sean Paul <seanpaul@chromium.org> (v5)
Tested-by: Robert Foss <robert.foss@collabora.com> (v5)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1479220628-10204-1-git-send-email-gustavo@padovan.org

1 files changed, 29 insertions, 0 deletions

diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index bcc1a4d1d1a6..946672f97e1e 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -731,6 +731,35 @@ struct drm_crtc {
 	 */
 	struct drm_crtc_crc crc;
 #endif
+
+	/**
+	 * @fence_context:
+	 *
+	 * timeline context used for fence operations.
+	 */
+	unsigned int fence_context;
+
+	/**
+	 * @fence_lock:
+	 *
+	 * spinlock to protect the fences in the fence_context.
+	 */
+
+	spinlock_t fence_lock;
+	/**
+	 * @fence_seqno:
+	 *
+	 * Seqno variable used as monotonic counter for the fences
+	 * created on the CRTC's timeline.
+	 */
+	unsigned long fence_seqno;
+
+	/**
+	 * @timeline_name:
+	 *
+	 * The name of the CRTC's fence timeline.
+	 */
+	char timeline_name[32];
 };
 
 /**