From: Gustavo Padovan gustavo.padovan@collabora.co.uk
There is now a new property called FENCE_FD attached to every plane state that receives the sync_file fd from userspace via the atomic commit IOCTL.
The fd is then translated to a fence (that may be a fence_collection 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.
Signed-off-by: Gustavo Padovan gustavo.padovan@collabora.co.uk
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. --- drivers/gpu/drm/Kconfig | 1 + drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++ drivers/gpu/drm/drm_atomic_helper.c | 3 +++ drivers/gpu/drm/drm_crtc.c | 7 +++++++ include/drm/drm_crtc.h | 1 + 5 files changed, 26 insertions(+)
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index f2a74d0..3c987e3 100644 --- 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 8ee1db8..13674c7 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -30,6 +30,7 @@ #include <drm/drm_atomic.h> #include <drm/drm_mode.h> #include <drm/drm_plane_helper.h> +#include <linux/sync_file.h>
/** * drm_atomic_state_default_release - @@ -680,6 +681,17 @@ 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_fence_fd) { + if (U642I64(val) == -1) + return 0; + + if (state->fence) + fence_put(state->fence); + + state->fence = sync_file_fences_get(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); @@ -737,6 +749,8 @@ 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_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 f1cfcce..866f332 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -2696,6 +2696,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane *plane, { if (state->fb) drm_framebuffer_unreference(state->fb); + + if (state->fence) + fence_put(state->fence); } EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 55ffde5..65212ce 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1278,6 +1278,7 @@ 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_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); @@ -1533,6 +1534,12 @@ 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, + "FENCE_FD", -1, INT_MAX); + if (!prop) + return -ENOMEM; + dev->mode_config.prop_fence_fd = prop; + prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC, "CRTC_ID", DRM_MODE_OBJECT_CRTC); if (!prop) diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 8cb377c..5ba3cda 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -2122,6 +2122,7 @@ struct drm_mode_config { struct drm_property *prop_crtc_w; struct drm_property *prop_crtc_h; struct drm_property *prop_fb_id; + struct drm_property *prop_fence_fd; struct drm_property *prop_crtc_id; struct drm_property *prop_active; struct drm_property *prop_mode_id;