On 2020-03-09 20:52, Laurent Pinchart wrote:
> Enable vblank handling when the CRTC is turned on and disable it when it
> is turned off. This requires moving vblank init after the KMS pipeline
> initialisation, otherwise drm_vblank_init() gets called with 0 CRTCs.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com>

With this patch applied I start to get system resets on my Colibri iMX7
test device during system boot shortly after initializing mxsfb. It
happens not on every boot, but rather often, I would say every second or
third. From what I can tell the interrupt handling should be safe, but
it seems that every now and then something races. Any idea what that
could be?

--
Stefan

> ---
>  drivers/gpu/drm/mxsfb/mxsfb_drv.c | 15 +++++++++------
>  drivers/gpu/drm/mxsfb/mxsfb_kms.c |  6 +++++-
>  2 files changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> index e324bd2a63a5..72b4f6a947a4 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_drv.c
> @@ -160,12 +160,6 @@ static int mxsfb_load(struct drm_device *drm,
> unsigned long flags)
>  
>       pm_runtime_enable(drm->dev);
>  
> -     ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
> -     if (ret < 0) {
> -             dev_err(drm->dev, "Failed to initialise vblank\n");
> -             goto err_vblank;
> -     }
> -
>       /* Modeset init */
>       drm_mode_config_init(drm);
>  
> @@ -175,6 +169,15 @@ static int mxsfb_load(struct drm_device *drm,
> unsigned long flags)
>               goto err_vblank;
>       }
>  
> +     ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
> +     if (ret < 0) {
> +             dev_err(drm->dev, "Failed to initialise vblank\n");
> +             goto err_vblank;
> +     }
> +
> +     /* Start with vertical blanking interrupt reporting disabled. */
> +     drm_crtc_vblank_off(&mxsfb->crtc);
> +
>       ret = mxsfb_attach_bridge(mxsfb);
>       if (ret) {
>               dev_err(drm->dev, "Cannot connect bridge: %d\n", ret);
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> index ac2696c8483d..640305fb1068 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> @@ -322,8 +322,10 @@ static void mxsfb_crtc_atomic_enable(struct drm_crtc 
> *crtc,
>       dma_addr_t paddr;
>  
>       pm_runtime_get_sync(drm->dev);
> -
>       mxsfb_enable_axi_clk(mxsfb);
> +
> +     drm_crtc_vblank_on(crtc);
> +
>       mxsfb_crtc_mode_set_nofb(mxsfb);
>  
>       /* Write cur_buf as well to avoid an initial corrupt frame */
> @@ -353,6 +355,8 @@ static void mxsfb_crtc_atomic_disable(struct drm_crtc 
> *crtc,
>       }
>       spin_unlock_irq(&drm->event_lock);
>  
> +     drm_crtc_vblank_off(crtc);
> +
>       mxsfb_disable_axi_clk(mxsfb);
>       pm_runtime_put_sync(drm->dev);
>  }
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

Reply via email to