[PATCH 1/2] drm: Stop using drm_vblank_count() as the hw frame counter

Ville Syrjälä ville.syrjala at linux.intel.com
Wed Sep 30 07:14:51 PDT 2015


On Wed, Sep 30, 2015 at 04:08:02PM +0200, Daniel Vetter wrote:
> On Wed, Sep 30, 2015 at 04:46:48PM +0300, ville.syrjala at linux.intel.com wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > drm_vblank_count() returns the software counter. We should not pretend
> > it's the hw counter since we use the hw counter to figuere out what the
> > software counter value should be. So instead provide a new function
> > drm_vblank_no_hw_counter() for drivers that don't have a real hw
> > counter. The new function simply returns 0, which is about the only
> > thing it can do.
> 
> Shouldn't we instead just make the get_vblank_counter hook optional?

Perhaps. But maybe this way would encourage people to go look for a
hw frame counter in their hardware?

> -Daniel
> 
> > 
> > Cc: Vincent Abriou <vincent.abriou at st.com>
> > Cc: Thierry Reding <treding at nvidia.com>
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > ---
> >  drivers/gpu/drm/armada/armada_drv.c          |  2 +-
> >  drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c |  2 +-
> >  drivers/gpu/drm/drm_irq.c                    | 17 +++++++++++++++++
> >  drivers/gpu/drm/exynos/exynos_drm_drv.c      |  2 +-
> >  drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c    |  2 +-
> >  drivers/gpu/drm/imx/imx-drm-core.c           |  2 +-
> >  drivers/gpu/drm/msm/msm_drv.c                |  2 +-
> >  drivers/gpu/drm/nouveau/nouveau_drm.c        |  2 +-
> >  drivers/gpu/drm/omapdrm/omap_drv.c           |  2 +-
> >  drivers/gpu/drm/rcar-du/rcar_du_drv.c        |  2 +-
> >  drivers/gpu/drm/rockchip/rockchip_drm_drv.c  |  2 +-
> >  drivers/gpu/drm/shmobile/shmob_drm_drv.c     |  2 +-
> >  drivers/gpu/drm/sti/sti_drv.c                |  2 +-
> >  drivers/gpu/drm/tilcdc/tilcdc_drv.c          |  2 +-
> >  include/drm/drmP.h                           |  1 +
> >  15 files changed, 31 insertions(+), 13 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/armada/armada_drv.c b/drivers/gpu/drm/armada/armada_drv.c
> > index 225034b..464a13f 100644
> > --- a/drivers/gpu/drm/armada/armada_drv.c
> > +++ b/drivers/gpu/drm/armada/armada_drv.c
> > @@ -300,7 +300,7 @@ static struct drm_driver armada_drm_driver = {
> >  	.lastclose		= armada_drm_lastclose,
> >  	.unload			= armada_drm_unload,
> >  	.set_busid		= drm_platform_set_busid,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= armada_drm_enable_vblank,
> >  	.disable_vblank		= armada_drm_disable_vblank,
> >  #ifdef CONFIG_DEBUG_FS
> > diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
> > index 8bc62ec..2eb1c66 100644
> > --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
> > +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
> > @@ -697,7 +697,7 @@ static struct drm_driver atmel_hlcdc_dc_driver = {
> >  	.irq_preinstall = atmel_hlcdc_dc_irq_uninstall,
> >  	.irq_postinstall = atmel_hlcdc_dc_irq_postinstall,
> >  	.irq_uninstall = atmel_hlcdc_dc_irq_uninstall,
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank = atmel_hlcdc_dc_enable_vblank,
> >  	.disable_vblank = atmel_hlcdc_dc_disable_vblank,
> >  	.gem_free_object = drm_gem_cma_free_object,
> > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
> > index ed2394e..7d70b7c 100644
> > --- a/drivers/gpu/drm/drm_irq.c
> > +++ b/drivers/gpu/drm/drm_irq.c
> > @@ -1797,3 +1797,20 @@ bool drm_crtc_handle_vblank(struct drm_crtc *crtc)
> >  	return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc));
> >  }
> >  EXPORT_SYMBOL(drm_crtc_handle_vblank);
> > +
> > +/**
> > + * drm_vblank_no_hw_counter - "No hw counter" implementation of .get_vblank_counter()
> > + * @dev: DRM device
> > + * @pipe: CRTC for which to read the counter
> > + *
> > + * Drivers can plug this into the .get_vblank_counter() function if
> > + * there is no useable hardware frame counter available.
> > + *
> > + * Returns:
> > + * 0
> > + */
> > +u32 drm_vblank_no_hw_counter(struct drm_device *dev, int pipe)
> > +{
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL(drm_vblank_no_hw_counter);
> > diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
> > index f0a5839..fb9cfc5 100644
> > --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
> > +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
> > @@ -447,7 +447,7 @@ static struct drm_driver exynos_drm_driver = {
> >  	.lastclose		= exynos_drm_lastclose,
> >  	.postclose		= exynos_drm_postclose,
> >  	.set_busid		= drm_platform_set_busid,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= exynos_drm_crtc_enable_vblank,
> >  	.disable_vblank		= exynos_drm_crtc_disable_vblank,
> >  	.gem_free_object	= exynos_drm_gem_free_object,
> > diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> > index 9a8e2da..1f4e8b9 100644
> > --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> > +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c
> > @@ -192,7 +192,7 @@ static struct drm_driver fsl_dcu_drm_driver = {
> >  	.unload			= fsl_dcu_unload,
> >  	.preclose		= fsl_dcu_drm_preclose,
> >  	.irq_handler		= fsl_dcu_drm_irq,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= fsl_dcu_drm_enable_vblank,
> >  	.disable_vblank		= fsl_dcu_drm_disable_vblank,
> >  	.gem_free_object	= drm_gem_cma_free_object,
> > diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c
> > index 74f505b..18a6642 100644
> > --- a/drivers/gpu/drm/imx/imx-drm-core.c
> > +++ b/drivers/gpu/drm/imx/imx-drm-core.c
> > @@ -487,7 +487,7 @@ static struct drm_driver imx_drm_driver = {
> >  	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
> >  	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
> >  	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= imx_drm_enable_vblank,
> >  	.disable_vblank		= imx_drm_disable_vblank,
> >  	.ioctls			= imx_drm_ioctls,
> > diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
> > index 0339c5d..3eba23f 100644
> > --- a/drivers/gpu/drm/msm/msm_drv.c
> > +++ b/drivers/gpu/drm/msm/msm_drv.c
> > @@ -978,7 +978,7 @@ static struct drm_driver msm_driver = {
> >  	.irq_preinstall     = msm_irq_preinstall,
> >  	.irq_postinstall    = msm_irq_postinstall,
> >  	.irq_uninstall      = msm_irq_uninstall,
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank      = msm_enable_vblank,
> >  	.disable_vblank     = msm_disable_vblank,
> >  	.gem_free_object    = msm_gem_free_object,
> > diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
> > index ccefb64..2416c7d 100644
> > --- a/drivers/gpu/drm/nouveau/nouveau_drm.c
> > +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
> > @@ -934,7 +934,7 @@ driver_stub = {
> >  	.debugfs_cleanup = nouveau_debugfs_takedown,
> >  #endif
> >  
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank = nouveau_display_vblank_enable,
> >  	.disable_vblank = nouveau_display_vblank_disable,
> >  	.get_scanout_position = nouveau_display_scanoutpos,
> > diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c
> > index d685e23..4d58934 100644
> > --- a/drivers/gpu/drm/omapdrm/omap_drv.c
> > +++ b/drivers/gpu/drm/omapdrm/omap_drv.c
> > @@ -839,7 +839,7 @@ static struct drm_driver omap_drm_driver = {
> >  	.preclose = dev_preclose,
> >  	.postclose = dev_postclose,
> >  	.set_busid = drm_platform_set_busid,
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank = omap_irq_enable_vblank,
> >  	.disable_vblank = omap_irq_disable_vblank,
> >  #ifdef CONFIG_DEBUG_FS
> > diff --git a/drivers/gpu/drm/rcar-du/rcar_du_drv.c b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > index 780ca11..3608e88 100644
> > --- a/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > +++ b/drivers/gpu/drm/rcar-du/rcar_du_drv.c
> > @@ -259,7 +259,7 @@ static struct drm_driver rcar_du_driver = {
> >  	.preclose		= rcar_du_preclose,
> >  	.lastclose		= rcar_du_lastclose,
> >  	.set_busid		= drm_platform_set_busid,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= rcar_du_enable_vblank,
> >  	.disable_vblank		= rcar_du_disable_vblank,
> >  	.gem_free_object	= drm_gem_cma_free_object,
> > diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> > index 9a0c291..b468add 100644
> > --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> > +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
> > @@ -277,7 +277,7 @@ static struct drm_driver rockchip_drm_driver = {
> >  	.load			= rockchip_drm_load,
> >  	.unload			= rockchip_drm_unload,
> >  	.lastclose		= rockchip_drm_lastclose,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= rockchip_drm_crtc_enable_vblank,
> >  	.disable_vblank		= rockchip_drm_crtc_disable_vblank,
> >  	.gem_vm_ops		= &rockchip_drm_vm_ops,
> > diff --git a/drivers/gpu/drm/shmobile/shmob_drm_drv.c b/drivers/gpu/drm/shmobile/shmob_drm_drv.c
> > index 666321d..108a03b 100644
> > --- a/drivers/gpu/drm/shmobile/shmob_drm_drv.c
> > +++ b/drivers/gpu/drm/shmobile/shmob_drm_drv.c
> > @@ -269,7 +269,7 @@ static struct drm_driver shmob_drm_driver = {
> >  	.preclose		= shmob_drm_preclose,
> >  	.set_busid		= drm_platform_set_busid,
> >  	.irq_handler		= shmob_drm_irq,
> > -	.get_vblank_counter	= drm_vblank_count,
> > +	.get_vblank_counter	= drm_vblank_no_hw_counter,
> >  	.enable_vblank		= shmob_drm_enable_vblank,
> >  	.disable_vblank		= shmob_drm_disable_vblank,
> >  	.gem_free_object	= drm_gem_cma_free_object,
> > diff --git a/drivers/gpu/drm/sti/sti_drv.c b/drivers/gpu/drm/sti/sti_drv.c
> > index 9f85988..f846996 100644
> > --- a/drivers/gpu/drm/sti/sti_drv.c
> > +++ b/drivers/gpu/drm/sti/sti_drv.c
> > @@ -201,7 +201,7 @@ static struct drm_driver sti_driver = {
> >  	.dumb_destroy = drm_gem_dumb_destroy,
> >  	.fops = &sti_driver_fops,
> >  
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank = sti_crtc_enable_vblank,
> >  	.disable_vblank = sti_crtc_disable_vblank,
> >  
> > diff --git a/drivers/gpu/drm/tilcdc/tilcdc_drv.c b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> > index 0f283a3..7e0b0c5 100644
> > --- a/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> > +++ b/drivers/gpu/drm/tilcdc/tilcdc_drv.c
> > @@ -563,7 +563,7 @@ static struct drm_driver tilcdc_driver = {
> >  	.irq_preinstall     = tilcdc_irq_preinstall,
> >  	.irq_postinstall    = tilcdc_irq_postinstall,
> >  	.irq_uninstall      = tilcdc_irq_uninstall,
> > -	.get_vblank_counter = drm_vblank_count,
> > +	.get_vblank_counter = drm_vblank_no_hw_counter,
> >  	.enable_vblank      = tilcdc_enable_vblank,
> >  	.disable_vblank     = tilcdc_disable_vblank,
> >  	.gem_free_object    = drm_gem_cma_free_object,
> > diff --git a/include/drm/drmP.h b/include/drm/drmP.h
> > index d0251ac..f563333 100644
> > --- a/include/drm/drmP.h
> > +++ b/include/drm/drmP.h
> > @@ -952,6 +952,7 @@ extern void drm_crtc_vblank_off(struct drm_crtc *crtc);
> >  extern void drm_crtc_vblank_reset(struct drm_crtc *crtc);
> >  extern void drm_crtc_vblank_on(struct drm_crtc *crtc);
> >  extern void drm_vblank_cleanup(struct drm_device *dev);
> > +extern u32 drm_vblank_no_hw_counter(struct drm_device *dev, int pipe);
> >  
> >  extern int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
> >  						 unsigned int pipe, int *max_error,
> > -- 
> > 2.4.6
> > 
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/dri-devel
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

-- 
Ville Syrjälä
Intel OTC


More information about the dri-devel mailing list