[PATCH] gpu: ipu-v3: image-convert: Wait for channels before disabling

[Steve Longerbeam]

Hi Philpp,

Please disregard this patch. A better solution to a busy wait with a 
spin lock held is to wait for all required EOF interrupts before doing 
tile completion processing. I will submit a new patch series.

Steve


On 6/9/20 5:51 PM, Steve Longerbeam wrote:
> Call ipu_idmac_wait_busy() on each idmac channel to busy wait for the
> channel to be idle before disabling. Otherwise it was found that a
> conversion would stall after the completion of a tile and the start
> of the next tile.
>
> Fixes: 0537db801bb01 ("gpu: ipu-v3: image-convert: reconfigure IC per tile")
> Signed-off-by: Steve Longerbeam <slongerbeam at gmail.com>
> ---
>   drivers/gpu/ipu-v3/ipu-image-convert.c | 21 +++++++++++++++++----
>   1 file changed, 17 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/ipu-v3/ipu-image-convert.c b/drivers/gpu/ipu-v3/ipu-image-convert.c
> index eeca50d9a1ee..f0938015d2fd 100644
> --- a/drivers/gpu/ipu-v3/ipu-image-convert.c
> +++ b/drivers/gpu/ipu-v3/ipu-image-convert.c
> @@ -1251,6 +1251,19 @@ static int get_run_count(struct ipu_image_convert_ctx *ctx,
>   	return count;
>   }
>   
> +static void stop_channel(struct ipu_image_convert_chan *chan,
> +			 struct ipuv3_channel *channel)
> +{
> +	struct ipu_image_convert_priv *priv = chan->priv;
> +	int ret;
> +
> +	ret = ipu_idmac_wait_busy(channel, 1);
> +	if (ret == -ETIMEDOUT)
> +		dev_warn(priv->ipu->dev, "IDMAC timeout\n");
> +
> +	ipu_idmac_disable_channel(channel);
> +}
> +
>   static void convert_stop(struct ipu_image_convert_run *run)
>   {
>   	struct ipu_image_convert_ctx *ctx = run->ctx;
> @@ -1262,12 +1275,12 @@ static void convert_stop(struct ipu_image_convert_run *run)
>   
>   	/* disable IC tasks and the channels */
>   	ipu_ic_task_disable(chan->ic);
> -	ipu_idmac_disable_channel(chan->in_chan);
> -	ipu_idmac_disable_channel(chan->out_chan);
> +	stop_channel(chan, chan->in_chan);
> +	stop_channel(chan, chan->out_chan);
>   
>   	if (ipu_rot_mode_is_irt(ctx->rot_mode)) {
> -		ipu_idmac_disable_channel(chan->rotation_in_chan);
> -		ipu_idmac_disable_channel(chan->rotation_out_chan);
> +		stop_channel(chan, chan->rotation_in_chan);
> +		stop_channel(chan, chan->rotation_out_chan);
>   		ipu_idmac_unlink(chan->out_chan, chan->rotation_in_chan);
>   	}
>