From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ec2-52-27-115-49.us-west-2.compute.amazonaws.com ([52.27.115.49]:37099 "EHLO osg.samsung.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750872AbdISQti (ORCPT ); Tue, 19 Sep 2017 12:49:38 -0400 Date: Tue, 19 Sep 2017 13:49:30 -0300 From: Mauro Carvalho Chehab To: Philipp Zabel Cc: Dave Stevenson , Mats Randgaard , Mauro Carvalho Chehab , Hans Verkuil , linux-media@vger.kernel.org Subject: Re: [PATCH 2/3] [media] tc358743: Increase FIFO level to 300. Message-ID: <20170919134930.6fa28562@recife.lan> In-Reply-To: <1505834685.10076.5.camel@pengutronix.de> References: <3e638375aff788b24f988e452214649d6100a596.1505826082.git.dave.stevenson@raspberrypi.org> <1505834685.10076.5.camel@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Tue, 19 Sep 2017 17:24:45 +0200 Philipp Zabel escreveu: > Hi Dave, > > On Tue, 2017-09-19 at 14:08 +0100, Dave Stevenson wrote: > > The existing fixed value of 16 worked for UYVY 720P60 over > > 2 lanes at 594MHz, or UYVY 1080P60 over 4 lanes. (RGB888 > > 1080P60 needs 6 lanes at 594MHz). > > It doesn't allow for lower resolutions to work as the FIFO > > underflows. > > > > Using a value of 300 works for all resolutions down to VGA60, > > and the increase in frame delay is <4usecs for 1080P60 UYVY > > (2.55usecs for RGB888). > > > > Signed-off-by: Dave Stevenson > > Can we increase this to 320? This would also allow > 720p60 at 594 Mbps / 4 lanes, according to the xls. Hmm... if this is dependent on the resolution and frame rate, wouldn't it be better to dynamically adjust it accordingly? Regards, Maur Thanks, Mauro