[PATCH v2 09/10] drm/imx: atomic phase 3 step 4: Use generic atomic page flip

Liu Ying gnuiyl at gmail.com
Tue May 31 09:24:30 UTC 2016


To support generic atomic page flip, this patch customizes ->atomic_commit
for nonblock commits.

Signed-off-by: Liu Ying <gnuiyl at gmail.com>
---
v1->v2:
* s/async/nonblock/ on this patch to address Daniel Vetter's comment.
* Wait for pending commit on each CRTC for both block and nonblock
  atomic mode settings.  This way, a block commit will not overwrite
  the hardware setting when a nonblock page flip is about to finish,
  so that the page flip may wait for vblank successfully.

 drivers/gpu/drm/imx/imx-drm-core.c | 135 +++++++++++++++++++++++++++++++-
 drivers/gpu/drm/imx/ipuv3-crtc.c   | 156 ++-----------------------------------
 2 files changed, 142 insertions(+), 149 deletions(-)

diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c
index 2a2ab8c..d2bb743 100644
--- a/drivers/gpu/drm/imx/imx-drm-core.c
+++ b/drivers/gpu/drm/imx/imx-drm-core.c
@@ -15,10 +15,14 @@
  */
 #include <linux/component.h>
 #include <linux/device.h>
+#include <linux/dma-buf.h>
 #include <linux/fb.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/reservation.h>
+#include <linux/wait.h>
 #include <drm/drmP.h>
+#include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_crtc_helper.h>
@@ -48,6 +52,14 @@ struct imx_drm_device {
 struct imx_drm_crtc {
 	struct drm_crtc				*crtc;
 	struct imx_drm_crtc_helper_funcs	imx_drm_helper_funcs;
+	wait_queue_head_t			commit_wait;
+	bool					commit_pending;
+};
+
+struct imx_drm_commit {
+	struct work_struct work;
+	struct drm_device *dev;
+	struct drm_atomic_state *state;
 };
 
 #if IS_ENABLED(CONFIG_DRM_FBDEV_EMULATION)
@@ -168,11 +180,130 @@ static void imx_drm_output_poll_changed(struct drm_device *drm)
 	drm_fbdev_cma_hotplug_event(imxdrm->fbhelper);
 }
 
+static void imx_drm_atomic_complete(struct imx_drm_commit *commit)
+{
+	struct drm_device *dev = commit->dev;
+	struct imx_drm_device *imxdrm = dev->dev_private;
+	struct imx_drm_crtc *imx_crtc;
+	struct drm_atomic_state *old_state = commit->state;
+	struct drm_crtc *crtc;
+	struct drm_crtc_state *old_crtc_state;
+	struct drm_plane_state *plane_state;
+	struct drm_gem_cma_object *cma_obj;
+	struct fence *excl;
+	unsigned shared_count;
+	struct fence **shared;
+	unsigned int i, j;
+	int ret;
+
+	/* Wait for fences. */
+	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
+		if (crtc->state->event) {
+			plane_state = crtc->primary->state;
+			cma_obj = drm_fb_cma_get_gem_obj(plane_state->fb, 0);
+			if (cma_obj->base.dma_buf) {
+				ret = reservation_object_get_fences_rcu(
+					cma_obj->base.dma_buf->resv, &excl,
+					&shared_count, &shared);
+				if (unlikely(ret))
+					DRM_ERROR("failed to get fences "
+						  "for buffer\n");
+
+				if (excl) {
+					fence_wait(excl, false);
+					fence_put(excl);
+				}
+				for (j = 0; j < shared_count; i++) {
+					fence_wait(shared[j], false);
+					fence_put(shared[j]);
+				}
+			}
+		}
+	}
+
+	/* Apply the atomic update. */
+	drm_atomic_helper_commit_modeset_disables(dev, old_state);
+	drm_atomic_helper_commit_modeset_enables(dev, old_state);
+	drm_atomic_helper_commit_planes(dev, old_state, false);
+	drm_atomic_helper_wait_for_vblanks(dev, old_state);
+	drm_atomic_helper_cleanup_planes(dev, old_state);
+
+	for_each_crtc_in_state(old_state, crtc, old_crtc_state, i) {
+		imx_crtc = imxdrm->crtc[i];
+
+		/* Complete the commit, wake up any waiter. */
+		spin_lock(&imx_crtc->commit_wait.lock);
+		imx_crtc->commit_pending = false;
+		wake_up_all_locked(&imx_crtc->commit_wait);
+		spin_unlock(&imx_crtc->commit_wait.lock);
+	}
+
+	drm_atomic_state_free(old_state);
+
+	kfree(commit);
+}
+
+static void imx_drm_atomic_work(struct work_struct *work)
+{
+	struct imx_drm_commit *commit =
+		container_of(work, struct imx_drm_commit, work);
+
+	imx_drm_atomic_complete(commit);
+}
+
+static int imx_drm_atomic_commit(struct drm_device *dev,
+				 struct drm_atomic_state *state, bool nonblock)
+{
+	struct imx_drm_device *imxdrm = dev->dev_private;
+	struct imx_drm_crtc *imx_crtc;
+	struct imx_drm_commit *commit;
+	struct drm_crtc *crtc;
+	struct drm_crtc_state *crtc_state;
+	unsigned int i;
+	int ret;
+
+	commit = kzalloc(sizeof(*commit), GFP_KERNEL);
+	if (commit == NULL)
+		return -ENOMEM;
+
+	commit->dev = dev;
+	commit->state = state;
+
+	for_each_crtc_in_state(state, crtc, crtc_state, i) {
+		imx_crtc = imxdrm->crtc[i];
+
+		spin_lock(&imx_crtc->commit_wait.lock);
+		ret = wait_event_interruptible_locked(
+				imx_crtc->commit_wait,
+				!imx_crtc->commit_pending);
+		if (ret == 0)
+			imx_crtc->commit_pending = true;
+		spin_unlock(&imx_crtc->commit_wait.lock);
+
+		if (ret) {
+			kfree(commit);
+			return ret;
+		}
+	}
+
+	if (nonblock)
+		INIT_WORK(&commit->work, imx_drm_atomic_work);
+
+	drm_atomic_helper_swap_state(dev, state);
+
+	if (nonblock)
+		schedule_work(&commit->work);
+	else
+		imx_drm_atomic_complete(commit);
+
+	return 0;
+}
+
 static const struct drm_mode_config_funcs imx_drm_mode_config_funcs = {
 	.fb_create = drm_fb_cma_create,
 	.output_poll_changed = imx_drm_output_poll_changed,
 	.atomic_check = drm_atomic_helper_check,
-	.atomic_commit = drm_atomic_helper_commit,
+	.atomic_commit = imx_drm_atomic_commit,
 };
 
 /*
@@ -307,6 +438,8 @@ int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 	imx_drm_crtc->imx_drm_helper_funcs = *imx_drm_helper_funcs;
 	imx_drm_crtc->crtc = crtc;
 
+	init_waitqueue_head(&imx_drm_crtc->commit_wait);
+
 	crtc->port = port;
 
 	imxdrm->crtc[imxdrm->pipes++] = imx_drm_crtc;
diff --git a/drivers/gpu/drm/imx/ipuv3-crtc.c b/drivers/gpu/drm/imx/ipuv3-crtc.c
index f20340f..7ee51db 100644
--- a/drivers/gpu/drm/imx/ipuv3-crtc.c
+++ b/drivers/gpu/drm/imx/ipuv3-crtc.c
@@ -24,8 +24,6 @@
 #include <linux/fb.h>
 #include <linux/clk.h>
 #include <linux/errno.h>
-#include <linux/reservation.h>
-#include <linux/dma-buf.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_fb_cma_helper.h>
 
@@ -35,23 +33,6 @@
 
 #define DRIVER_DESC		"i.MX IPUv3 Graphics"
 
-enum ipu_flip_status {
-	IPU_FLIP_NONE,
-	IPU_FLIP_PENDING,
-	IPU_FLIP_SUBMITTED,
-};
-
-struct ipu_flip_work {
-	struct work_struct		unref_work;
-	struct drm_gem_object		*bo;
-	struct drm_pending_vblank_event *page_flip_event;
-	struct work_struct		fence_work;
-	struct ipu_crtc			*crtc;
-	struct fence			*excl;
-	unsigned			shared_count;
-	struct fence			**shared;
-};
-
 struct ipu_crtc {
 	struct device		*dev;
 	struct drm_crtc		base;
@@ -62,9 +43,6 @@ struct ipu_crtc {
 
 	struct ipu_dc		*dc;
 	struct ipu_di		*di;
-	enum ipu_flip_status	flip_state;
-	struct workqueue_struct *flip_queue;
-	struct ipu_flip_work	*flip_work;
 	int			irq;
 };
 
@@ -92,150 +70,35 @@ static void ipu_crtc_disable(struct drm_crtc *crtc)
 	drm_crtc_vblank_off(&ipu_crtc->base);
 }
 
-static void ipu_flip_unref_work_func(struct work_struct *__work)
-{
-	struct ipu_flip_work *work =
-			container_of(__work, struct ipu_flip_work, unref_work);
-
-	drm_gem_object_unreference_unlocked(work->bo);
-	kfree(work);
-}
-
-static void ipu_flip_fence_work_func(struct work_struct *__work)
-{
-	struct ipu_flip_work *work =
-			container_of(__work, struct ipu_flip_work, fence_work);
-	int i;
-
-	/* wait for all fences attached to the FB obj to signal */
-	if (work->excl) {
-		fence_wait(work->excl, false);
-		fence_put(work->excl);
-	}
-	for (i = 0; i < work->shared_count; i++) {
-		fence_wait(work->shared[i], false);
-		fence_put(work->shared[i]);
-	}
-
-	work->crtc->flip_state = IPU_FLIP_SUBMITTED;
-}
-
-static int ipu_page_flip(struct drm_crtc *crtc,
-		struct drm_framebuffer *fb,
-		struct drm_pending_vblank_event *event,
-		uint32_t page_flip_flags)
-{
-	struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0);
-	struct ipu_crtc *ipu_crtc = to_ipu_crtc(crtc);
-	struct ipu_flip_work *flip_work;
-	int ret;
-
-	if (ipu_crtc->flip_state != IPU_FLIP_NONE)
-		return -EBUSY;
-
-	ret = imx_drm_crtc_vblank_get(ipu_crtc->imx_crtc);
-	if (ret) {
-		dev_dbg(ipu_crtc->dev, "failed to acquire vblank counter\n");
-		list_del(&event->base.link);
-
-		return ret;
-	}
-
-	flip_work = kzalloc(sizeof *flip_work, GFP_KERNEL);
-	if (!flip_work) {
-		ret = -ENOMEM;
-		goto put_vblank;
-	}
-	INIT_WORK(&flip_work->unref_work, ipu_flip_unref_work_func);
-	flip_work->page_flip_event = event;
-
-	/* get BO backing the old framebuffer and take a reference */
-	flip_work->bo = &drm_fb_cma_get_gem_obj(crtc->primary->fb, 0)->base;
-	drm_gem_object_reference(flip_work->bo);
-
-	ipu_crtc->flip_work = flip_work;
-	/*
-	 * If the object has a DMABUF attached, we need to wait on its fences
-	 * if there are any.
-	 */
-	if (cma_obj->base.dma_buf) {
-		INIT_WORK(&flip_work->fence_work, ipu_flip_fence_work_func);
-		flip_work->crtc = ipu_crtc;
-
-		ret = reservation_object_get_fences_rcu(
-				cma_obj->base.dma_buf->resv, &flip_work->excl,
-				&flip_work->shared_count, &flip_work->shared);
-
-		if (unlikely(ret)) {
-			DRM_ERROR("failed to get fences for buffer\n");
-			goto free_flip_work;
-		}
-
-		/* No need to queue the worker if the are no fences */
-		if (!flip_work->excl && !flip_work->shared_count) {
-			ipu_crtc->flip_state = IPU_FLIP_SUBMITTED;
-		} else {
-			ipu_crtc->flip_state = IPU_FLIP_PENDING;
-			queue_work(ipu_crtc->flip_queue,
-				   &flip_work->fence_work);
-		}
-	} else {
-		ipu_crtc->flip_state = IPU_FLIP_SUBMITTED;
-	}
-
-	if (crtc->primary->state)
-		drm_atomic_set_fb_for_plane(crtc->primary->state, fb);
-
-	return 0;
-
-free_flip_work:
-	drm_gem_object_unreference_unlocked(flip_work->bo);
-	kfree(flip_work);
-	ipu_crtc->flip_work = NULL;
-put_vblank:
-	imx_drm_crtc_vblank_put(ipu_crtc->imx_crtc);
-
-	return ret;
-}
-
 static const struct drm_crtc_funcs ipu_crtc_funcs = {
 	.set_config = drm_atomic_helper_set_config,
 	.destroy = drm_crtc_cleanup,
-	.page_flip = ipu_page_flip,
+	.page_flip = drm_atomic_helper_page_flip,
 	.reset = drm_atomic_helper_crtc_reset,
 	.atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
 	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
 };
 
-static void ipu_crtc_handle_pageflip(struct ipu_crtc *ipu_crtc)
+static void ipu_crtc_handle_pageflip(struct drm_crtc *crtc)
 {
+	struct drm_device *drm = crtc->dev;
 	unsigned long flags;
-	struct drm_device *drm = ipu_crtc->base.dev;
-	struct ipu_flip_work *work = ipu_crtc->flip_work;
 
 	spin_lock_irqsave(&drm->event_lock, flags);
-	if (work->page_flip_event)
-		drm_crtc_send_vblank_event(&ipu_crtc->base,
-					   work->page_flip_event);
-	imx_drm_crtc_vblank_put(ipu_crtc->imx_crtc);
+	drm_crtc_send_vblank_event(crtc, crtc->state->event);
+	crtc->state->event = NULL;
 	spin_unlock_irqrestore(&drm->event_lock, flags);
 }
 
 static irqreturn_t ipu_irq_handler(int irq, void *dev_id)
 {
 	struct ipu_crtc *ipu_crtc = dev_id;
+	struct drm_crtc *crtc = &ipu_crtc->base;
 
 	imx_drm_handle_vblank(ipu_crtc->imx_crtc);
 
-	if (ipu_crtc->flip_state == IPU_FLIP_SUBMITTED) {
-		struct ipu_plane *plane = ipu_crtc->plane[0];
-
-		ipu_plane_set_base(plane, ipu_crtc->base.primary->fb);
-		ipu_crtc_handle_pageflip(ipu_crtc);
-		queue_work(ipu_crtc->flip_queue,
-			   &ipu_crtc->flip_work->unref_work);
-		ipu_crtc->flip_state = IPU_FLIP_NONE;
-	}
+	if (crtc->state->event)
+		ipu_crtc_handle_pageflip(crtc);
 
 	return IRQ_HANDLED;
 }
@@ -458,8 +321,6 @@ static int ipu_crtc_init(struct ipu_crtc *ipu_crtc,
 	/* Only enable IRQ when we actually need it to trigger work. */
 	disable_irq(ipu_crtc->irq);
 
-	ipu_crtc->flip_queue = create_singlethread_workqueue("ipu-crtc-flip");
-
 	return 0;
 
 err_put_plane1_res:
@@ -504,7 +365,6 @@ static void ipu_drm_unbind(struct device *dev, struct device *master,
 
 	imx_drm_remove_crtc(ipu_crtc->imx_crtc);
 
-	destroy_workqueue(ipu_crtc->flip_queue);
 	ipu_put_resources(ipu_crtc);
 	if (ipu_crtc->plane[1])
 		ipu_plane_put_resources(ipu_crtc->plane[1]);
-- 
2.7.4



More information about the dri-devel mailing list