| Message ID | 20210624072916.27703-1-tzimmermann@suse.de |
|---|---|
| Headers | show |
| Series | Deprecate struct drm_device.irq_enabled | expand |
On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: > For KMS drivers, replace the IRQ check in VBLANK ioctls with a check for > vblank support. IRQs might be enabled wthout vblanking being supported. > > This change also removes the DRM framework's only dependency on IRQ state > for non-legacy drivers. For legacy drivers with userspace modesetting, > the original test remains in drm_wait_vblank_ioctl(). > > v3: > * optimize test in drm_wait_vblank_ioctl() for KMS case (Liviu) > * update docs for drm_irq_uninstall() > v2: > * keep the old test for legacy drivers in > drm_wait_vblank_ioctl() (Daniel) > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> > --- > drivers/gpu/drm/drm_irq.c | 13 ++++--------- > drivers/gpu/drm/drm_vblank.c | 16 ++++++++++++---- > 2 files changed, 16 insertions(+), 13 deletions(-) > > diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c > index c3bd664ea733..945dd82e2ea3 100644 > --- a/drivers/gpu/drm/drm_irq.c > +++ b/drivers/gpu/drm/drm_irq.c > @@ -74,10 +74,8 @@ > * only supports devices with a single interrupt on the main device stored in > * &drm_device.dev and set as the device paramter in drm_dev_alloc(). > * > - * These IRQ helpers are strictly optional. Drivers which roll their own only > - * need to set &drm_device.irq_enabled to signal the DRM core that vblank > - * interrupts are working. Since these helpers don't automatically clean up the > - * requested interrupt like e.g. devm_request_irq() they're not really > + * These IRQ helpers are strictly optional. Since these helpers don't automatically > + * clean up the requested interrupt like e.g. devm_request_irq() they're not really > * recommended. > */ > > @@ -91,9 +89,7 @@ > * and after the installation. > * > * This is the simplified helper interface provided for drivers with no special > - * needs. Drivers which need to install interrupt handlers for multiple > - * interrupts must instead set &drm_device.irq_enabled to signal the DRM core > - * that vblank interrupts are available. > + * needs. > * > * @irq must match the interrupt number that would be passed to request_irq(), > * if called directly instead of using this helper function. > @@ -156,8 +152,7 @@ EXPORT_SYMBOL(drm_irq_install); > * > * Calls the driver's &drm_driver.irq_uninstall function and unregisters the IRQ > * handler. This should only be called by drivers which used drm_irq_install() > - * to set up their interrupt handler. Other drivers must only reset > - * &drm_device.irq_enabled to false. > + * to set up their interrupt handler. > * > * Note that for kernel modesetting drivers it is a bug if this function fails. > * The sanity checks are only to catch buggy user modesetting drivers which call > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > index 3417e1ac7918..10fe16bafcb6 100644 > --- a/drivers/gpu/drm/drm_vblank.c > +++ b/drivers/gpu/drm/drm_vblank.c > @@ -1748,8 +1748,16 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, > unsigned int pipe_index; > unsigned int flags, pipe, high_pipe; > > - if (!dev->irq_enabled) > - return -EOPNOTSUPP; > +#if defined(CONFIG_DRM_LEGACY) > + if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) { > + if (!dev->irq_enabled) > + return -EOPNOTSUPP; > + } else /* if DRIVER_MODESET */ > +#endif > + { > + if (!drm_dev_has_vblank(dev)) > + return -EOPNOTSUPP; > + } Sheesh I hate this kind of inline #ifdefs. Two alternate suggestions that I believe should be as just efficient: 1) The more verbose: #if defined(CONFIG_DRM_LEGACY) static bool drm_wait_vblank_supported(struct drm_device *dev) { if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) return dev->irq_enabled; else return drm_dev_has_vblank(dev); } #else static bool drm_wait_vblank_supported(struct drm_device *dev) { return drm_dev_has_vblank(dev); } #endif 2) The more compact: static bool drm_wait_vblank_supported(struct drm_device *dev) { if (IS_ENABLED(CONFIG_DRM_LEGACY) && unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) return dev->irq_enabled; else return drm_dev_has_vblank(dev); } Then, in drm_wait_vblank_ioctl(). if (!drm_wait_vblank_supported(dev)) return -EOPNOTSUPP; The compiler should do the right thing without any explicit inline keywords etc. BR, Jani. > > if (vblwait->request.type & _DRM_VBLANK_SIGNAL) > return -EINVAL; > @@ -2023,7 +2031,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > - if (!dev->irq_enabled) > + if (!drm_dev_has_vblank(dev)) > return -EOPNOTSUPP; > > crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id); > @@ -2082,7 +2090,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > return -EOPNOTSUPP; > > - if (!dev->irq_enabled) > + if (!drm_dev_has_vblank(dev)) > return -EOPNOTSUPP; > > crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id);
Hi Am 24.06.21 um 10:06 schrieb Jani Nikula: > On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: >> For KMS drivers, replace the IRQ check in VBLANK ioctls with a check for >> vblank support. IRQs might be enabled wthout vblanking being supported. >> >> This change also removes the DRM framework's only dependency on IRQ state >> for non-legacy drivers. For legacy drivers with userspace modesetting, >> the original test remains in drm_wait_vblank_ioctl(). >> >> v3: >> * optimize test in drm_wait_vblank_ioctl() for KMS case (Liviu) >> * update docs for drm_irq_uninstall() >> v2: >> * keep the old test for legacy drivers in >> drm_wait_vblank_ioctl() (Daniel) >> >> Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> >> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> >> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> >> --- >> drivers/gpu/drm/drm_irq.c | 13 ++++--------- >> drivers/gpu/drm/drm_vblank.c | 16 ++++++++++++---- >> 2 files changed, 16 insertions(+), 13 deletions(-) >> >> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c >> index c3bd664ea733..945dd82e2ea3 100644 >> --- a/drivers/gpu/drm/drm_irq.c >> +++ b/drivers/gpu/drm/drm_irq.c >> @@ -74,10 +74,8 @@ >> * only supports devices with a single interrupt on the main device stored in >> * &drm_device.dev and set as the device paramter in drm_dev_alloc(). >> * >> - * These IRQ helpers are strictly optional. Drivers which roll their own only >> - * need to set &drm_device.irq_enabled to signal the DRM core that vblank >> - * interrupts are working. Since these helpers don't automatically clean up the >> - * requested interrupt like e.g. devm_request_irq() they're not really >> + * These IRQ helpers are strictly optional. Since these helpers don't automatically >> + * clean up the requested interrupt like e.g. devm_request_irq() they're not really >> * recommended. >> */ >> >> @@ -91,9 +89,7 @@ >> * and after the installation. >> * >> * This is the simplified helper interface provided for drivers with no special >> - * needs. Drivers which need to install interrupt handlers for multiple >> - * interrupts must instead set &drm_device.irq_enabled to signal the DRM core >> - * that vblank interrupts are available. >> + * needs. >> * >> * @irq must match the interrupt number that would be passed to request_irq(), >> * if called directly instead of using this helper function. >> @@ -156,8 +152,7 @@ EXPORT_SYMBOL(drm_irq_install); >> * >> * Calls the driver's &drm_driver.irq_uninstall function and unregisters the IRQ >> * handler. This should only be called by drivers which used drm_irq_install() >> - * to set up their interrupt handler. Other drivers must only reset >> - * &drm_device.irq_enabled to false. >> + * to set up their interrupt handler. >> * >> * Note that for kernel modesetting drivers it is a bug if this function fails. >> * The sanity checks are only to catch buggy user modesetting drivers which call >> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c >> index 3417e1ac7918..10fe16bafcb6 100644 >> --- a/drivers/gpu/drm/drm_vblank.c >> +++ b/drivers/gpu/drm/drm_vblank.c >> @@ -1748,8 +1748,16 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, >> unsigned int pipe_index; >> unsigned int flags, pipe, high_pipe; >> >> - if (!dev->irq_enabled) >> - return -EOPNOTSUPP; >> +#if defined(CONFIG_DRM_LEGACY) >> + if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) { >> + if (!dev->irq_enabled) >> + return -EOPNOTSUPP; >> + } else /* if DRIVER_MODESET */ >> +#endif >> + { >> + if (!drm_dev_has_vblank(dev)) >> + return -EOPNOTSUPP; >> + } > > Sheesh I hate this kind of inline #ifdefs. I don't like them either. I guess I'll go with suggestion 2. Thanks for the feedback. Best regards Thomas > > Two alternate suggestions that I believe should be as just efficient: > > 1) The more verbose: > > #if defined(CONFIG_DRM_LEGACY) > static bool drm_wait_vblank_supported(struct drm_device *dev) > { > if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) > return dev->irq_enabled; > else > return drm_dev_has_vblank(dev); > } > #else > static bool drm_wait_vblank_supported(struct drm_device *dev) > { > return drm_dev_has_vblank(dev); > } > #endif > > 2) The more compact: > > static bool drm_wait_vblank_supported(struct drm_device *dev) > { > if (IS_ENABLED(CONFIG_DRM_LEGACY) && unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) > return dev->irq_enabled; > else > return drm_dev_has_vblank(dev); > } > > Then, in drm_wait_vblank_ioctl(). > > if (!drm_wait_vblank_supported(dev)) > return -EOPNOTSUPP; > > The compiler should do the right thing without any explicit inline > keywords etc. > > BR, > Jani. > >> >> if (vblwait->request.type & _DRM_VBLANK_SIGNAL) >> return -EINVAL; >> @@ -2023,7 +2031,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, >> if (!drm_core_check_feature(dev, DRIVER_MODESET)) >> return -EOPNOTSUPP; >> >> - if (!dev->irq_enabled) >> + if (!drm_dev_has_vblank(dev)) >> return -EOPNOTSUPP; >> >> crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id); >> @@ -2082,7 +2090,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, >> if (!drm_core_check_feature(dev, DRIVER_MODESET)) >> return -EOPNOTSUPP; >> >> - if (!dev->irq_enabled) >> + if (!drm_dev_has_vblank(dev)) >> return -EOPNOTSUPP; >> >> crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id); >
On Thu, 2021-06-24 at 09:29 +0200, Thomas Zimmermann wrote: > The field drm_device.irq_enabled is only used by legacy drivers > with userspace modesetting. Don't set it in imx. > > v3: > * move dcss changes into separate patch (Laurentiu) > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> > --- > drivers/gpu/drm/imx/imx-drm-core.c | 11 ----------- > 1 file changed, 11 deletions(-) > > diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c > index 76819a8ac37f..9558e9e1b431 100644 > --- a/drivers/gpu/drm/imx/imx-drm-core.c > +++ b/drivers/gpu/drm/imx/imx-drm-core.c > @@ -207,17 +207,6 @@ static int imx_drm_bind(struct device *dev) > if (IS_ERR(drm)) > return PTR_ERR(drm); > > - /* > - * enable drm irq mode. > - * - with irq_enabled = true, we can use the vblank feature. > - * > - * P.S. note that we wouldn't use drm irq handler but > - * just specific driver own one instead because > - * drm framework supports only one irq handler and > - * drivers can well take care of their interrupts > - */ > - drm->irq_enabled = true; > - > /* > * set max width and height as default value(4096x4096). > * this value would be used to check framebuffer size limitation Acked-by: Philipp Zabel <p.zabel@pengutronix.de> regards Philipp
On Thu, Jun 24, 2021 at 11:07:57AM +0200, Thomas Zimmermann wrote: > Hi > > Am 24.06.21 um 10:51 schrieb Jani Nikula: > > On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: > > > Hi > > > > > > Am 24.06.21 um 10:06 schrieb Jani Nikula: > > > > On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: > > > > > diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c > > > > > index 3417e1ac7918..10fe16bafcb6 100644 > > > > > --- a/drivers/gpu/drm/drm_vblank.c > > > > > +++ b/drivers/gpu/drm/drm_vblank.c > > > > > @@ -1748,8 +1748,16 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, > > > > > unsigned int pipe_index; > > > > > unsigned int flags, pipe, high_pipe; > > > > > - if (!dev->irq_enabled) > > > > > - return -EOPNOTSUPP; > > > > > +#if defined(CONFIG_DRM_LEGACY) > > > > > + if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) { > > > > > + if (!dev->irq_enabled) > > > > > + return -EOPNOTSUPP; > > > > > + } else /* if DRIVER_MODESET */ > > > > > +#endif > > > > > + { > > > > > + if (!drm_dev_has_vblank(dev)) > > > > > + return -EOPNOTSUPP; > > > > > + } > > > > > > > > Sheesh I hate this kind of inline #ifdefs. > > > > > > > > Two alternate suggestions that I believe should be as just efficient: > > > > > > Or how about: > > > > > > static bool drm_wait_vblank_supported(struct drm_device *dev) > > > > > > { > > > > > > if defined(CONFIG_DRM_LEGACY) > > > if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) > > > > > > return dev->irq_enabled; > > > > > > #endif > > > return drm_dev_has_vblank(dev); > > > > > > } > > > > > > > > > ? > > > > > > It's inline, but still readable. > > > > It's definitely better than the original, but it's unclear to me why > > you'd prefer this over option 2) below. I guess the only reason I can > > think of is emphasizing the conditional compilation. However, > > IS_ENABLED() is widely used in this manner specifically to avoid inline > > #if, and the compiler optimizes it away. > > It's simply more readable to me as the condition is simpler. But option 2 is > also ok. Either option looks good to me. Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> Thanks for doing that! Liviu > > Best regards > Thomas > > > > > BR, > > Jani. > > > > > > > > > > Best regards > > > Thomas > > > > > > > > > > > 1) The more verbose: > > > > > > > > #if defined(CONFIG_DRM_LEGACY) > > > > static bool drm_wait_vblank_supported(struct drm_device *dev) > > > > { > > > > if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) > > > > return dev->irq_enabled; > > > > else > > > > return drm_dev_has_vblank(dev); > > > > } > > > > #else > > > > static bool drm_wait_vblank_supported(struct drm_device *dev) > > > > { > > > > return drm_dev_has_vblank(dev); > > > > } > > > > #endif > > > > > > > > 2) The more compact: > > > > > > > > static bool drm_wait_vblank_supported(struct drm_device *dev) > > > > { > > > > if (IS_ENABLED(CONFIG_DRM_LEGACY) && unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) > > > > return dev->irq_enabled; > > > > else > > > > return drm_dev_has_vblank(dev); > > > > } > > > > > > > > Then, in drm_wait_vblank_ioctl(). > > > > > > > > if (!drm_wait_vblank_supported(dev)) > > > > return -EOPNOTSUPP; > > > > > > > > The compiler should do the right thing without any explicit inline > > > > keywords etc. > > > > > > > > BR, > > > > Jani. > > > > > > > > > if (vblwait->request.type & _DRM_VBLANK_SIGNAL) > > > > > return -EINVAL; > > > > > @@ -2023,7 +2031,7 @@ int drm_crtc_get_sequence_ioctl(struct drm_device *dev, void *data, > > > > > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > > > > > return -EOPNOTSUPP; > > > > > - if (!dev->irq_enabled) > > > > > + if (!drm_dev_has_vblank(dev)) > > > > > return -EOPNOTSUPP; > > > > > crtc = drm_crtc_find(dev, file_priv, get_seq->crtc_id); > > > > > @@ -2082,7 +2090,7 @@ int drm_crtc_queue_sequence_ioctl(struct drm_device *dev, void *data, > > > > > if (!drm_core_check_feature(dev, DRIVER_MODESET)) > > > > > return -EOPNOTSUPP; > > > > > - if (!dev->irq_enabled) > > > > > + if (!drm_dev_has_vblank(dev)) > > > > > return -EOPNOTSUPP; > > > > > crtc = drm_crtc_find(dev, file_priv, queue_seq->crtc_id); > > > > > > > > -- > Thomas Zimmermann > Graphics Driver Developer > SUSE Software Solutions Germany GmbH > Maxfeldstr. 5, 90409 Nürnberg, Germany > (HRB 36809, AG Nürnberg) > Geschäftsführer: Felix Imendörffer >
On Thu, Jun 24, 2021 at 09:29:10AM +0200, Thomas Zimmermann wrote: > The field drm_device.irq_enabled is only used by legacy drivers > with userspace modesetting. Don't set it in tegra. > > Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> > --- > drivers/gpu/drm/tegra/drm.c | 7 ------- > 1 file changed, 7 deletions(-) Acked-by: Thierry Reding <treding@nvidia.com>
Hi Am 24.06.21 um 14:36 schrieb Jani Nikula: > On Thu, 24 Jun 2021, Thierry Reding <thierry.reding@gmail.com> wrote: >> On Thu, Jun 24, 2021 at 11:07:57AM +0200, Thomas Zimmermann wrote: >>> Hi >>> >>> Am 24.06.21 um 10:51 schrieb Jani Nikula: >>>> On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: >>>>> Hi >>>>> >>>>> Am 24.06.21 um 10:06 schrieb Jani Nikula: >>>>>> On Thu, 24 Jun 2021, Thomas Zimmermann <tzimmermann@suse.de> wrote: >>>>>>> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c >>>>>>> index 3417e1ac7918..10fe16bafcb6 100644 >>>>>>> --- a/drivers/gpu/drm/drm_vblank.c >>>>>>> +++ b/drivers/gpu/drm/drm_vblank.c >>>>>>> @@ -1748,8 +1748,16 @@ int drm_wait_vblank_ioctl(struct drm_device *dev, void *data, >>>>>>> unsigned int pipe_index; >>>>>>> unsigned int flags, pipe, high_pipe; >>>>>>> - if (!dev->irq_enabled) >>>>>>> - return -EOPNOTSUPP; >>>>>>> +#if defined(CONFIG_DRM_LEGACY) >>>>>>> + if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) { >>>>>>> + if (!dev->irq_enabled) >>>>>>> + return -EOPNOTSUPP; >>>>>>> + } else /* if DRIVER_MODESET */ >>>>>>> +#endif >>>>>>> + { >>>>>>> + if (!drm_dev_has_vblank(dev)) >>>>>>> + return -EOPNOTSUPP; >>>>>>> + } >>>>>> >>>>>> Sheesh I hate this kind of inline #ifdefs. >>>>>> >>>>>> Two alternate suggestions that I believe should be as just efficient: >>>>> >>>>> Or how about: >>>>> >>>>> static bool drm_wait_vblank_supported(struct drm_device *dev) >>>>> >>>>> { >>>>> >>>>> if defined(CONFIG_DRM_LEGACY) >>>>> if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) >>>>> >>>>> return dev->irq_enabled; >>>>> >>>>> #endif >>>>> return drm_dev_has_vblank(dev); >>>>> >>>>> } >>>>> >>>>> >>>>> ? >>>>> >>>>> It's inline, but still readable. >>>> >>>> It's definitely better than the original, but it's unclear to me why >>>> you'd prefer this over option 2) below. I guess the only reason I can >>>> think of is emphasizing the conditional compilation. However, >>>> IS_ENABLED() is widely used in this manner specifically to avoid inline >>>> #if, and the compiler optimizes it away. >>> >>> It's simply more readable to me as the condition is simpler. But option 2 is >>> also ok. >> >> Perhaps do something like this, then: >> >> if (IS_ENABLED(CONFIG_DRM_LEGACY)) { >> if (unlikely(drm_core_check_feature(dev, DRIVER_LEGACY))) >> return dev->irq_enabled; >> } >> >> return drm_dev_has_vblank(dev); >> >> That's about just as readable as the variant involving the preprocessor >> but has all the benefits of not using the preprocessor. > > Looks like a winner to me. :) That's the most readable. But I just remembered that irq_enabled will likely become legacy-only in the device structure. We'll need an ifdef variant then. :/ Best regards Thomas > > BR, > Jani. > >