drm: add vblank hooks to struct drm_crtc_funcs

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 DRIVER_MODESET drivers.

The new hooks get plugged into core by adding wrapper functions for
vblank handling code.  The .get_vblank_counter hook is effectively
optional, as we provide drm_vblank_no_hw_counter() as the default
fallback in the wrapper function.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1486458995-31018-2-git-send-email-shawnguo@kernel.org

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index e06cf11ebb4a92154af07d3266b9e2ed6eb0eee5..646b3e57b9ad9ce33b7e4f95703c0f2cecc4912f 100644 (file)
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -89,6 +89,21 @@ 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);
+       }
+
+       if (dev->driver->get_vblank_counter)
+               return dev->driver->get_vblank_counter(dev, pipe);
+
+       return drm_vblank_no_hw_counter(dev, pipe);
+}
+
 /*
  * Reset the stored timestamp for the current vblank count to correspond
  * to the last vblank occurred.
@@ -112,9 +127,9 @@ 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 +183,9 @@ 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 +290,20 @@ 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;
+               }
+       }
+
+       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 +327,7 @@ 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;
        }
 
@@ -1027,6 +1056,18 @@ 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);
+       }
+
+       return dev->driver->enable_vblank(dev, pipe);
+}
+
 /**
  * drm_vblank_enable - enable the vblank interrupt on a CRTC
  * @dev: DRM device
@@ -1052,7 +1093,7 @@ 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 c38a572c16aa976f41af7aaa50841b460590e4e6..bda9347554a121ea665bac5e1eb73a2dec946729 100644 (file)
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -608,6 +608,50 @@ 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.
+        *
+        * This callback is optional. If a device doesn't have a hardware
+        * counter, the driver can simply leave the hook as NULL. The DRM core
+        * will account for missed vblank events while interrupts where disabled
+        * based on system timestamps.
+        *
+        * Wraparound handling and loss of events due to modesetting is dealt
+        * with in the DRM core code, as long as drivers call
+        * drm_crtc_vblank_off() and drm_crtc_vblank_on() when disabling or
+        * enabling a CRTC.
+        *
+        * 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 5699f42195fe1b9e1f26b825372423baad8906fd..8f8b9a1e55e6a5c63f8a6beb50da0a059544917e 100644 (file)
--- a/include/drm/drm_drv.h
+++ b/include/drm/drm_drv.h
@@ -130,6 +130,9 @@ 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.
@@ -142,6 +145,9 @@ 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
@@ -154,6 +160,9 @@ 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);