Re: [PATCH 17/24] drm/vblank: merge drm_vblank_restore() into drm_crtc_vblank_restore()

[Thomas Zimmermann <tzimmermann@suse.de>]

Am 10.11.25 um 17:17 schrieb Jani Nikula:
> The extra function serves no useful purpose.
>
> This allows us to drop another superfluous pipe check warning.
>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>

> ---
>   drivers/gpu/drm/drm_vblank.c | 57 +++++++++++++++---------------------
>   1 file changed, 23 insertions(+), 34 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c
> index 0ff69b06b2bd..64cd96207ad5 100644
> --- a/drivers/gpu/drm/drm_vblank.c
> +++ b/drivers/gpu/drm/drm_vblank.c
> @@ -1524,23 +1524,41 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc)
>   }
>   EXPORT_SYMBOL(drm_crtc_vblank_on);
>   
> -static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
> +/**
> + * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count.
> + * @crtc: CRTC in question
> + *
> + * Power manamement features can cause frame counter resets between vblank
> + * disable and enable. Drivers can use this function in their
> + * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
> + * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
> + * vblank counter.
> + *
> + * Note that drivers must have race-free high-precision timestamping support,
> + * i.e.  &drm_crtc_funcs.get_vblank_timestamp must be hooked up and
> + * &drm_vblank_crtc_config.disable_immediate must be set to indicate the
> + * time-stamping functions are race-free against vblank hardware counter
> + * increments.
> + */
> +void drm_crtc_vblank_restore(struct drm_crtc *crtc)
>   {
> +	struct drm_device *dev = crtc->dev;
> +	unsigned int pipe = drm_crtc_index(crtc);
> +	struct drm_vblank_crtc *vblank = drm_crtc_vblank_crtc(crtc);
>   	ktime_t t_vblank;
> -	struct drm_vblank_crtc *vblank;
>   	int framedur_ns;
>   	u64 diff_ns;
>   	u32 cur_vblank, diff = 1;
>   	int count = DRM_TIMESTAMP_MAXRETRIES;
>   	u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
>   
> -	if (drm_WARN_ON(dev, pipe >= dev->num_crtcs))
> -		return;
> +	drm_WARN_ON_ONCE(dev, !crtc->funcs->get_vblank_timestamp);
> +	drm_WARN_ON_ONCE(dev, vblank->inmodeset);
> +	drm_WARN_ON_ONCE(dev, !vblank->config.disable_immediate);
>   
>   	assert_spin_locked(&dev->vbl_lock);
>   	assert_spin_locked(&dev->vblank_time_lock);
>   
> -	vblank = drm_vblank_crtc(dev, pipe);
>   	drm_WARN_ONCE(dev,
>   		      drm_debug_enabled(DRM_UT_VBL) && !vblank->framedur_ns,
>   		      "Cannot compute missed vblanks without frame duration\n");
> @@ -1561,35 +1579,6 @@ static void drm_vblank_restore(struct drm_device *dev, unsigned int pipe)
>   		    diff, diff_ns, framedur_ns, cur_vblank - vblank->last);
>   	vblank->last = (cur_vblank - diff) & max_vblank_count;
>   }
> -
> -/**
> - * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count.
> - * @crtc: CRTC in question
> - *
> - * Power manamement features can cause frame counter resets between vblank
> - * disable and enable. Drivers can use this function in their
> - * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since
> - * the last &drm_crtc_funcs.disable_vblank using timestamps and update the
> - * vblank counter.
> - *
> - * Note that drivers must have race-free high-precision timestamping support,
> - * i.e.  &drm_crtc_funcs.get_vblank_timestamp must be hooked up and
> - * &drm_vblank_crtc_config.disable_immediate must be set to indicate the
> - * time-stamping functions are race-free against vblank hardware counter
> - * increments.
> - */
> -void drm_crtc_vblank_restore(struct drm_crtc *crtc)
> -{
> -	struct drm_device *dev = crtc->dev;
> -	unsigned int pipe = drm_crtc_index(crtc);
> -	struct drm_vblank_crtc *vblank = drm_vblank_crtc(dev, pipe);
> -
> -	drm_WARN_ON_ONCE(dev, !crtc->funcs->get_vblank_timestamp);
> -	drm_WARN_ON_ONCE(dev, vblank->inmodeset);
> -	drm_WARN_ON_ONCE(dev, !vblank->config.disable_immediate);
> -
> -	drm_vblank_restore(dev, pipe);
> -}
>   EXPORT_SYMBOL(drm_crtc_vblank_restore);
>   
>   static int drm_queue_vblank_event(struct drm_vblank_crtc *vblank,

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)