From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([213.167.242.64]:36860 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727872AbeINUD3 (ORCPT ); Fri, 14 Sep 2018 16:03:29 -0400 From: Laurent Pinchart To: Kieran Bingham Cc: mchehab@kernel.org, linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Kieran Bingham Subject: Re: [PATCH v2 2/2] media: vsp1: Document max_width restriction on UDS Date: Fri, 14 Sep 2018 17:48:50 +0300 Message-ID: <7357198.ccT2EWLa9U@avalon> In-Reply-To: <20180914142652.30484-2-kieran.bingham+renesas@ideasonboard.com> References: <20180914142652.30484-1-kieran.bingham+renesas@ideasonboard.com> <20180914142652.30484-2-kieran.bingham+renesas@ideasonboard.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Kieran, Thank you for the patch. On Friday, 14 September 2018 17:26:52 EEST Kieran Bingham wrote: > The UDS is currently restricted based on a partition size of 256 pixels. > Document the actual restrictions, but don't increase the implementation. > > The extended partition algorithm may later choose to utilise a larger > partition size to support overlapping partitions which will improve the > quality of the output images. > > Signed-off-by: Kieran Bingham Reviewed-by: Laurent Pinchart > --- > drivers/media/platform/vsp1/vsp1_uds.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/media/platform/vsp1/vsp1_uds.c > b/drivers/media/platform/vsp1/vsp1_uds.c index 75c613050151..e8340de85813 > 100644 > --- a/drivers/media/platform/vsp1/vsp1_uds.c > +++ b/drivers/media/platform/vsp1/vsp1_uds.c > @@ -342,6 +342,14 @@ static unsigned int uds_max_width(struct vsp1_entity > *entity, UDS_PAD_SOURCE); > hscale = output->width / input->width; > > + /* > + * The maximum width of the UDS is 304 pixels. These are input pixels > + * in the event of up-scaling, and output pixels in the event of > + * downscaling. > + * > + * To support overlapping parition windows we clamp at units of 256 and > + * the remaining pixels are reserved. > + */ > if (hscale <= 2) > return 256; > else if (hscale <= 4) -- Regards, Laurent Pinchart