On Tue, Jun 8, 2021 at 11:18 AM Daniel Vetter daniel@ffwll.ch wrote:
On Tue, Jun 08, 2021 at 11:03:01AM +0200, Thomas Zimmermann wrote:
Replace the IRQ check in VBLANK ioctls with a check for vblank support. IRQs might be enabled wthout vblanking being supported.
Nah, or if they are, that's a broken driver. irq_enabled here really only means vblank_irq_enabled (maybe we should rename it). I'd like to understand the motivation here a bit better to make sure we'r not just papering over a driver bug.
Also as-is this breaks legacy drivers, which do enable/disable irqs at runtime with the legacy IRQ_CONTROL ioctl, so we can't just throw this out. Hence this cleanup here is only ok for non-legacy drivers.
Finally if you do this cleanup I think we should go through drivers and drop the irq_enabled = true settings that are littered around. For that cleanup I think this patch makes sense.
I forgot to add: We already do this check that you're adding here because later on we validate the provided crtc index against dev->num_crtcs. vblank support is confusing because it lives both in a kms and legacy driver world. -Daniel
This change also removes the DRM framework's only dependency on IRQ state for non-legacy drivers.
Signed-off-by: Thomas Zimmermann tzimmermann@suse.de
drivers/gpu/drm/drm_irq.c | 10 +++------- drivers/gpu/drm/drm_vblank.c | 6 +++--- 2 files changed, 6 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index c3bd664ea733..1d7785721323 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.
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index 3417e1ac7918..165286fef478 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -1748,7 +1748,7 @@ 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)
if (!drm_dev_has_vblank(dev)) return -EOPNOTSUPP; if (vblwait->request.type & _DRM_VBLANK_SIGNAL)@@ -2023,7 +2023,7 @@ 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 +2082,7 @@ 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);-- 2.31.1
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch