drm/fence: add in-fences support

There is now a new property called IN_FENCE_FD attached to every plane
state that receives sync_file fds from userspace via the atomic commit
IOCTL.

The fd is then translated to a fence (that may be a fence_array
subclass or just a normal fence) and then used by DRM to fence_wait() for
all fences in the sync_file to signal. So it only commits when all
framebuffers are ready to scanout.

v2: Comments by Daniel Vetter:
	- remove set state->fence = NULL in destroy phase
	- accept fence -1 as valid and just return 0
	- do not call fence_get() - sync_file_fences_get() already calls it
	- fence_put() if state->fence is already set, in case userspace
	set the property more than once.

v3: WARN_ON if fence is set but state has no FB

v4: Comment from Maarten Lankhorst
	- allow set fence with no related fb

v5: rename FENCE_FD to IN_FENCE_FD

v6: Comments by Daniel Vetter:
	- rename plane_state->in_fence back to "fence"
	- re-introduce WARN_ON if fence set but no fb

     - rebase after fence -> dma_fence rename

v7: Comments by Brian Starkey
	- set state->fence to NULL when duplicating the state
	- fail if IN_FENCE_FD was already set

v8: rebase against latest drm-misc

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Brian Starkey <brian.starkey@arm.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Tested-by: Robert Foss <robert.foss@collabora.com>
[danvet: Rebase onto extracted drm_mode_config.[hc].]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 863cdca..95fc041 100644 (file)
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -12,6 +12,7 @@ menuconfig DRM
        select I2C
        select I2C_ALGOBIT
        select DMA_SHARED_BUFFER
+       select SYNC_FILE
        help
          Kernel-level support for the Direct Rendering Infrastructure (DRI)
          introduced in XFree86 4.0. If you say Y here, you need to select

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 57e0a6e..3ad780a 100644 (file)
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -31,6 +31,7 @@
 #include <drm/drm_mode.h>
 #include <drm/drm_plane_helper.h>
 #include <drm/drm_print.h>
+#include <linux/sync_file.h>
 
 #include "drm_crtc_internal.h"
 
@@ -712,6 +713,17 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
                drm_atomic_set_fb_for_plane(state, fb);
                if (fb)
                        drm_framebuffer_unreference(fb);
+       } else if (property == config->prop_in_fence_fd) {
+               if (state->fence)
+                       return -EINVAL;
+
+               if (U642I64(val) == -1)
+                       return 0;
+
+               state->fence = sync_file_get_fence(val);
+               if (!state->fence)
+                       return -EINVAL;
+
        } else if (property == config->prop_crtc_id) {
                struct drm_crtc *crtc = drm_crtc_find(dev, val);
                return drm_atomic_set_crtc_for_plane(state, crtc);
@@ -773,6 +785,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
 
        if (property == config->prop_fb_id) {
                *val = (state->fb) ? state->fb->base.id : 0;
+       } else if (property == config->prop_in_fence_fd) {
+               *val = -1;
        } else if (property == config->prop_crtc_id) {
                *val = (state->crtc) ? state->crtc->base.id : 0;
        } else if (property == config->prop_crtc_x) {

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 5007796..0b16587 100644 (file)
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3072,6 +3072,8 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
 
        if (state->fb)
                drm_framebuffer_reference(state->fb);
+
+       state->fence = NULL;
 }
 EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
 
@@ -3110,6 +3112,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
 {
        if (state->fb)
                drm_framebuffer_unreference(state->fb);
+
+       if (state->fence)
+               dma_fence_put(state->fence);
 }
 EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
 

diff --git a/drivers/gpu/drm/drm_mode_config.c b/drivers/gpu/drm/drm_mode_config.c
index 6f80886..8bee2ad 100644 (file)
--- a/drivers/gpu/drm/drm_mode_config.c
+++ b/drivers/gpu/drm/drm_mode_config.c
@@ -308,6 +308,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
                return -ENOMEM;
        dev->mode_config.prop_fb_id = prop;
 
+       prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
+                       "IN_FENCE_FD", -1, INT_MAX);
+       if (!prop)
+               return -ENOMEM;
+       dev->mode_config.prop_in_fence_fd = prop;
+
        prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_ID", DRM_MODE_OBJECT_CRTC);
        if (!prop)

diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 2ba0c22..419ac31 100644 (file)
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -137,6 +137,7 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
 
        if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
                drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
+               drm_object_attach_property(&plane->base, config->prop_in_fence_fd, -1);
                drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);

diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 5d11b25..c6754cc 100644 (file)
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -481,6 +481,11 @@ struct drm_mode_config {
         */
        struct drm_property *prop_fb_id;
        /**
+        * @prop_in_fence_fd: Sync File fd representing the incoming fences
+        * for a Plane.
+        */
+       struct drm_property *prop_in_fence_fd;
+       /**
         * @prop_crtc_id: Default atomic plane property to specify the
         * &drm_crtc.
         */