drm: writeback: Add out-fences for writeback connectors (b13cc8dd) · Commits · 戴 / test

drivers/gpu/drm/drm_atomic.c

+90 −9

Original line number	Diff line number	Diff line
		@@ -318,6 +318,35 @@ static s32 __user get_out_fence_for_crtc(struct drm_atomic_state state,
		return fence_ptr;
		}

		static int set_out_fence_for_connector(struct drm_atomic_state *state,
		struct drm_connector *connector,
		s32 __user *fence_ptr)
		{
		unsigned int index = drm_connector_index(connector);

		if (!fence_ptr)
		return 0;

		if (put_user(-1, fence_ptr))
		return -EFAULT;

		state->connectors[index].out_fence_ptr = fence_ptr;

		return 0;
		}

		static s32 __user get_out_fence_for_connector(struct drm_atomic_state state,
		struct drm_connector *connector)
		{
		unsigned int index = drm_connector_index(connector);
		s32 __user *fence_ptr;

		fence_ptr = state->connectors[index].out_fence_ptr;
		state->connectors[index].out_fence_ptr = NULL;

		return fence_ptr;
		}

		/**
		* drm_atomic_set_mode_for_crtc - set mode for CRTC
		* @state: the CRTC whose incoming state to update
		@@ -727,6 +756,12 @@ static int drm_atomic_connector_check(struct drm_connector *connector,
		return -EINVAL;
		}

		if (writeback_job->out_fence && !writeback_job->fb) {
		DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] requesting out-fence without framebuffer\n",
		connector->base.id, connector->name);
		return -EINVAL;
		}

		return 0;
		}

		@@ -1367,6 +1402,11 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
		if (fb)
		drm_framebuffer_put(fb);
		return ret;
		} else if (property == config->writeback_out_fence_ptr_property) {
		s32 __user *fence_ptr = u64_to_user_ptr(val);

		return set_out_fence_for_connector(state->state, connector,
		fence_ptr);
		} else if (connector->funcs->atomic_set_property) {
		return connector->funcs->atomic_set_property(connector,
		state, property, val);
		@@ -1456,6 +1496,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
		} else if (property == config->writeback_fb_id_property) {
		/* Writeback framebuffer is one-shot, write and forget */
		*val = 0;
		} else if (property == config->writeback_out_fence_ptr_property) {
		*val = 0;
		} else if (connector->funcs->atomic_get_property) {
		return connector->funcs->atomic_get_property(connector,
		state, property, val);
		@@ -2292,7 +2334,7 @@ static int setup_out_fence(struct drm_out_fence_state *fence_state,
		return 0;
		}

		static int prepare_crtc_signaling(struct drm_device *dev,
		static int prepare_signaling(struct drm_device *dev,
		struct drm_atomic_state *state,
		struct drm_mode_atomic *arg,
		struct drm_file *file_priv,
		@@ -2301,6 +2343,8 @@ static int prepare_crtc_signaling(struct drm_device *dev,
		{
		struct drm_crtc *crtc;
		struct drm_crtc_state *crtc_state;
		struct drm_connector *conn;
		struct drm_connector_state *conn_state;
		int i, c = 0, ret;

		if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)
		@@ -2366,6 +2410,43 @@ static int prepare_crtc_signaling(struct drm_device *dev,
		c++;
		}

		for_each_new_connector_in_state(state, conn, conn_state, i) {
		struct drm_writeback_job *job;
		struct drm_out_fence_state *f;
		struct dma_fence *fence;
		s32 __user *fence_ptr;

		fence_ptr = get_out_fence_for_connector(state, conn);
		if (!fence_ptr)
		continue;

		job = drm_atomic_get_writeback_job(conn_state);
		if (!job)
		return -ENOMEM;

		f = krealloc(fence_state, sizeof(fence_state)
		(*num_fences + 1), GFP_KERNEL);
		if (!f)
		return -ENOMEM;

		memset(&f[num_fences], 0, sizeof(f));

		f[*num_fences].out_fence_ptr = fence_ptr;
		*fence_state = f;

		fence = drm_writeback_get_out_fence((struct drm_writeback_connector *)conn);
		if (!fence)
		return -ENOMEM;

		ret = setup_out_fence(&f[(*num_fences)++], fence);
		if (ret) {
		dma_fence_put(fence);
		return ret;
		}

		job->out_fence = fence;
		}

		/*
		* Having this flag means user mode pends on event which will never
		* reach due to lack of at least one CRTC for signaling
		@@ -2376,7 +2457,7 @@ static int prepare_crtc_signaling(struct drm_device *dev,
		return 0;
		}

		static void complete_crtc_signaling(struct drm_device *dev,
		static void complete_signaling(struct drm_device *dev,
		struct drm_atomic_state *state,
		struct drm_out_fence_state *fence_state,
		unsigned int num_fences,
		@@ -2550,7 +2631,7 @@ retry:
		drm_mode_object_put(obj);
		}

		ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
		ret = prepare_signaling(dev, state, arg, file_priv, &fence_state,
		&num_fences);
		if (ret)
		goto out;
		@@ -2567,7 +2648,7 @@ retry:
		}

		out:
		complete_crtc_signaling(dev, state, fence_state, num_fences, !ret);
		complete_signaling(dev, state, fence_state, num_fences, !ret);

		if (ret == -EDEADLK) {
		drm_atomic_state_clear(state);

drivers/gpu/drm/drm_writeback.c

+107 −2

Original line number	Diff line number	Diff line
		@@ -14,6 +14,7 @@
		#include <drm/drm_property.h>
		#include <drm/drm_writeback.h>
		#include <drm/drmP.h>
		#include <linux/dma-fence.h>

		/**
		* DOC: overview
		@@ -31,6 +32,16 @@
		* framebuffer applies only to a single commit (see below). A framebuffer may
		* not be attached while the CRTC is off.
		*
		* Unlike with planes, when a writeback framebuffer is removed by userspace DRM
		* makes no attempt to remove it from active use by the connector. This is
		* because no method is provided to abort a writeback operation, and in any
		* case making a new commit whilst a writeback is ongoing is undefined (see
		* WRITEBACK_OUT_FENCE_PTR below). As soon as the current writeback is finished,
		* the framebuffer will automatically no longer be in active use. As it will
		* also have already been removed from the framebuffer list, there will be no
		* way for any userspace application to retrieve a reference to it in the
		* intervening period.
		*
		* Writeback connectors have some additional properties, which userspace
		* can use to query and control them:
		*
		@@ -47,8 +58,54 @@
		* data is an array of u32 DRM_FORMAT_* fourcc values.
		* Userspace can use this blob to find out what pixel formats are supported
		* by the connector's writeback engine.
		*
		* "WRITEBACK_OUT_FENCE_PTR":
		* Userspace can use this property to provide a pointer for the kernel to
		* fill with a sync_file file descriptor, which will signal once the
		* writeback is finished. The value should be the address of a 32-bit
		* signed integer, cast to a u64.
		* Userspace should wait for this fence to signal before making another
		* commit affecting any of the same CRTCs, Planes or Connectors.
		* Failure to do so will result in undefined behaviour.
		* For this reason it is strongly recommended that all userspace
		* applications making use of writeback connectors always retrieve an
		* out-fence for the commit and use it appropriately.
		* From userspace, this property will always read as zero.
		*/

		#define fence_to_wb_connector(x) container_of(x->lock, \
		struct drm_writeback_connector, \
		fence_lock)

		static const char drm_writeback_fence_get_driver_name(struct dma_fence fence)
		{
		struct drm_writeback_connector *wb_connector =
		fence_to_wb_connector(fence);

		return wb_connector->base.dev->driver->name;
		}

		static const char *
		drm_writeback_fence_get_timeline_name(struct dma_fence *fence)
		{
		struct drm_writeback_connector *wb_connector =
		fence_to_wb_connector(fence);

		return wb_connector->timeline_name;
		}

		static bool drm_writeback_fence_enable_signaling(struct dma_fence *fence)
		{
		return true;
		}

		static const struct dma_fence_ops drm_writeback_fence_ops = {
		.get_driver_name = drm_writeback_fence_get_driver_name,
		.get_timeline_name = drm_writeback_fence_get_timeline_name,
		.enable_signaling = drm_writeback_fence_enable_signaling,
		.wait = dma_fence_default_wait,
		};

		static int create_writeback_properties(struct drm_device *dev)
		{
		struct drm_property *prop;
		@@ -72,6 +129,15 @@ static int create_writeback_properties(struct drm_device *dev)
		dev->mode_config.writeback_pixel_formats_property = prop;
		}

		if (!dev->mode_config.writeback_out_fence_ptr_property) {
		prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
		"WRITEBACK_OUT_FENCE_PTR", 0,
		U64_MAX);
		if (!prop)
		return -ENOMEM;
		dev->mode_config.writeback_out_fence_ptr_property = prop;
		}

		return 0;
		}

		@@ -141,6 +207,15 @@ int drm_writeback_connector_init(struct drm_device *dev,
		INIT_LIST_HEAD(&wb_connector->job_queue);
		spin_lock_init(&wb_connector->job_lock);

		wb_connector->fence_context = dma_fence_context_alloc(1);
		spin_lock_init(&wb_connector->fence_lock);
		snprintf(wb_connector->timeline_name,
		sizeof(wb_connector->timeline_name),
		"CONNECTOR:%d-%s", connector->base.id, connector->name);

		drm_object_attach_property(&connector->base,
		config->writeback_out_fence_ptr_property, 0);

		drm_object_attach_property(&connector->base,
		config->writeback_fb_id_property, 0);

		@@ -210,6 +285,7 @@ static void cleanup_work(struct work_struct *work)
		/**
		* drm_writeback_signal_completion - Signal the completion of a writeback job
		* @wb_connector: The writeback connector whose job is complete
		* @status: Status code to set in the writeback out_fence (0 for success)
		*
		* Drivers should call this to signal the completion of a previously queued
		* writeback job. It should be called as soon as possible after the hardware
		@@ -223,7 +299,8 @@ static void cleanup_work(struct work_struct *work)
		* See also: drm_writeback_queue_job()
		*/
		void
		drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector)
		drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector,
		int status)
		{
		unsigned long flags;
		struct drm_writeback_job *job;
		@@ -232,8 +309,15 @@ drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector)
		job = list_first_entry_or_null(&wb_connector->job_queue,
		struct drm_writeback_job,
		list_entry);
		if (job)
		if (job) {
		list_del(&job->list_entry);
		if (job->out_fence) {
		if (status)
		dma_fence_set_error(job->out_fence, status);
		dma_fence_signal(job->out_fence);
		dma_fence_put(job->out_fence);
		}
		}
		spin_unlock_irqrestore(&wb_connector->job_lock, flags);

		if (WARN_ON(!job))
		@@ -243,3 +327,24 @@ drm_writeback_signal_completion(struct drm_writeback_connector *wb_connector)
		queue_work(system_long_wq, &job->cleanup_work);
		}
		EXPORT_SYMBOL(drm_writeback_signal_completion);

		struct dma_fence *
		drm_writeback_get_out_fence(struct drm_writeback_connector *wb_connector)
		{
		struct dma_fence *fence;

		if (WARN_ON(wb_connector->base.connector_type !=
		DRM_MODE_CONNECTOR_WRITEBACK))
		return NULL;

		fence = kzalloc(sizeof(*fence), GFP_KERNEL);
		if (!fence)
		return NULL;

		dma_fence_init(fence, &drm_writeback_fence_ops,
		&wb_connector->fence_lock, wb_connector->fence_context,
		++wb_connector->fence_seqno);

		return fence;
		}
		EXPORT_SYMBOL(drm_writeback_get_out_fence);

include/drm/drm_atomic.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -160,6 +160,14 @@ struct __drm_crtcs_state {
		struct __drm_connnectors_state {
		struct drm_connector *ptr;
		struct drm_connector_state state, old_state, *new_state;
		/**
		* @out_fence_ptr:
		*
		* User-provided pointer which the kernel uses to return a sync_file
		* file descriptor. Used by writeback connectors to signal completion of
		* the writeback.
		*/
		s32 __user *out_fence_ptr;
		};

		struct drm_private_obj;

include/drm/drm_connector.h

+4 −4

Original line number	Diff line number	Diff line
		@@ -441,10 +441,10 @@ struct drm_connector_state {
		/**
		* @writeback_job: Writeback job for writeback connectors
		*
		* Holds the framebuffer for a writeback connector. As the writeback
		* completion may be asynchronous to the normal commit cycle, the
		* writeback job lifetime is managed separately from the normal atomic
		* state by this object.
		* Holds the framebuffer and out-fence for a writeback connector. As
		* the writeback completion may be asynchronous to the normal commit
		* cycle, the writeback job lifetime is managed separately from the
		* normal atomic state by this object.
		*
		* See also: drm_writeback_queue_job() and
		* drm_writeback_signal_completion()

include/drm/drm_mode_config.h

+8 −0

Original line number	Diff line number	Diff line
		@@ -798,6 +798,14 @@ struct drm_mode_config {
		* See also: drm_writeback_connector_init()
		*/
		struct drm_property *writeback_pixel_formats_property;
		/**
		* @writeback_out_fence_ptr_property: Property for writeback connectors,
		* fd pointer representing the outgoing fences for a writeback
		* connector. Userspace should provide a pointer to a value of type s32,
		* and then cast that pointer to u64.
		* See also: drm_writeback_connector_init()
		*/
		struct drm_property *writeback_out_fence_ptr_property;

		/* dumb ioctl parameters */
		uint32_t preferred_depth, prefer_shadow;

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