[RFC PATCH v2 1/5] drm: add vblank hooks to struct drm_crtc_funcs

Shawn Guo shawnguo at kernel.org
Sun Jan 22 06:09:02 UTC 2017


From: Shawn Guo <shawn.guo at linaro.org>

The vblank is mostly CRTC specific and implemented as part of CRTC
driver.  Let's keep the vblank hooks struct drm_driver for legacy
drivers, and add corresponding hooks in struct drm_crtc_funcs.  These
hooks take struct drm_crtc pointer as argument, and will be called by
core vblank handling code for MODESET drivers.

Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
 drivers/gpu/drm/drm_irq.c | 53 +++++++++++++++++++++++++++++++++++++++++------
 include/drm/drm_crtc.h    | 34 ++++++++++++++++++++++++++++++
 include/drm/drm_drv.h     |  9 ++++++++
 3 files changed, 90 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 88c69e71102e..604a2acda9d6 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -89,6 +89,19 @@ static void store_vblank(struct drm_device *dev, unsigned int pipe,
 	write_sequnlock(&vblank->seqlock);
 }
 
+static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe)
+{
+	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+
+		if (crtc->funcs->get_vblank_counter)
+			return crtc->funcs->get_vblank_counter(crtc);
+	}
+
+	/* fallback for legacy drivers */
+	return dev->driver->get_vblank_counter(dev, pipe);
+}
+
 /*
  * Reset the stored timestamp for the current vblank count to correspond
  * to the last vblank occurred.
@@ -112,9 +125,9 @@ static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe
 	 * when drm_vblank_enable() applies the diff
 	 */
 	do {
-		cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
+		cur_vblank = __get_vblank_counter(dev, pipe);
 		rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, 0);
-	} while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
+	} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
 
 	/*
 	 * Only reinitialize corresponding vblank timestamp if high-precision query
@@ -168,9 +181,9 @@ static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe,
 	 * corresponding vblank timestamp.
 	 */
 	do {
-		cur_vblank = dev->driver->get_vblank_counter(dev, pipe);
+		cur_vblank = __get_vblank_counter(dev, pipe);
 		rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, flags);
-	} while (cur_vblank != dev->driver->get_vblank_counter(dev, pipe) && --count > 0);
+	} while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0);
 
 	if (dev->max_vblank_count != 0) {
 		/* trust the hw counter when it's around */
@@ -275,6 +288,21 @@ u32 drm_accurate_vblank_count(struct drm_crtc *crtc)
 }
 EXPORT_SYMBOL(drm_accurate_vblank_count);
 
+static void __disable_vblank(struct drm_device *dev, unsigned int pipe)
+{
+	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+
+		if (crtc->funcs->disable_vblank) {
+			crtc->funcs->disable_vblank(crtc);
+			return;
+		}
+	}
+
+	/* fallback for legacy drivers */
+	dev->driver->disable_vblank(dev, pipe);
+}
+
 /*
  * Disable vblank irq's on crtc, make sure that last vblank count
  * of hardware and corresponding consistent software vblank counter
@@ -298,7 +326,7 @@ static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe)
 	 * hardware potentially runtime suspended.
 	 */
 	if (vblank->enabled) {
-		dev->driver->disable_vblank(dev, pipe);
+		__disable_vblank(dev, pipe);
 		vblank->enabled = false;
 	}
 
@@ -1054,6 +1082,19 @@ void drm_crtc_send_vblank_event(struct drm_crtc *crtc,
 }
 EXPORT_SYMBOL(drm_crtc_send_vblank_event);
 
+static int __enable_vblank(struct drm_device *dev, unsigned int pipe)
+{
+	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
+		struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+
+		if (crtc->funcs->enable_vblank)
+			return crtc->funcs->enable_vblank(crtc);
+	}
+
+	/* fallback for legacy drivers */
+	return dev->driver->enable_vblank(dev, pipe);
+}
+
 /**
  * drm_vblank_enable - enable the vblank interrupt on a CRTC
  * @dev: DRM device
@@ -1079,7 +1120,7 @@ static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe)
 		 * timestamps. Filtercode in drm_handle_vblank() will
 		 * prevent double-accounting of same vblank interval.
 		 */
-		ret = dev->driver->enable_vblank(dev, pipe);
+		ret = __enable_vblank(dev, pipe);
 		DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret);
 		if (ret)
 			atomic_dec(&vblank->refcount);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 06c943d1e04c..8b2f7266eada 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -600,6 +600,40 @@ struct drm_crtc_funcs {
 	 */
 	void (*atomic_print_state)(struct drm_printer *p,
 				   const struct drm_crtc_state *state);
+
+	/**
+	 * @get_vblank_counter:
+	 *
+	 * Driver callback for fetching a raw hardware vblank counter for the
+	 * CRTC. It's meant to be used by new drivers as the replacement of
+	 * &drm_driver.get_vblank_counter hook.
+	 *
+	 * Returns:
+	 *
+	 * Raw vblank counter value.
+	 */
+	u32 (*get_vblank_counter)(struct drm_crtc *crtc);
+
+	/**
+	 * @enable_vblank:
+	 *
+	 * Enable vblank interrupts for the CRTC. It's meant to be used by
+	 * new drivers as the replacement of &drm_driver.enable_vblank hook.
+	 *
+	 * Returns:
+	 *
+	 * Zero on success, appropriate errno if the vblank interrupt cannot
+	 * be enabled.
+	 */
+	int (*enable_vblank)(struct drm_crtc *crtc);
+
+	/**
+	 * @disable_vblank:
+	 *
+	 * Disable vblank interrupts for the CRTC. It's meant to be used by
+	 * new drivers as the replacement of &drm_driver.disable_vblank hook.
+	 */
+	void (*disable_vblank)(struct drm_crtc *crtc);
 };
 
 /**
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h
index 34ece393c639..6c325baddc40 100644
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -123,6 +123,9 @@ struct drm_driver {
 	 * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
 	 * enabling a CRTC.
 	 *
+	 * This is deprecated and should not be used by new drivers.
+	 * Use &drm_crtc_funcs.get_vblank_counter instead.
+	 *
 	 * Returns:
 	 *
 	 * Raw vblank counter value.
@@ -135,6 +138,9 @@ struct drm_driver {
 	 * Enable vblank interrupts for the CRTC specified with the pipe
 	 * argument.
 	 *
+	 * This is deprecated and should not be used by new drivers.
+	 * Use &drm_crtc_funcs.enable_vblank instead.
+	 *
 	 * Returns:
 	 *
 	 * Zero on success, appropriate errno if the given @crtc's vblank
@@ -147,6 +153,9 @@ struct drm_driver {
 	 *
 	 * Disable vblank interrupts for the CRTC specified with the pipe
 	 * argument.
+	 *
+	 * This is deprecated and should not be used by new drivers.
+	 * Use &drm_crtc_funcs.disable_vblank instead.
 	 */
 	void (*disable_vblank) (struct drm_device *dev, unsigned int pipe);
 
-- 
1.9.1



More information about the dri-devel mailing list