From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH] ARM: dts: sun4i: Add simplefb node with de_fe0-de_be0-lcd0-hdmi pipeline Date: Wed, 21 Jan 2015 09:56:48 +0100 Message-ID: <20150121085648.GB4367@lukather> References: <1421672477-12978-1-git-send-email-hdegoede@redhat.com> <1421672477-12978-2-git-send-email-hdegoede@redhat.com> Reply-To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="4rQ9lIe3OahbhU4J" Return-path: Content-Disposition: inline In-Reply-To: <1421672477-12978-2-git-send-email-hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: Hans de Goede Cc: Ian Campbell , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree , linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org List-Id: devicetree@vger.kernel.org --4rQ9lIe3OahbhU4J Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline On Mon, Jan 19, 2015 at 02:01:17PM +0100, Hans de Goede wrote: > Testing has shown that on sun4i the display backend engine does not have > deep enough fifo-s causing flickering / tearing in full-hd mode due to > fifo underruns. This can be avoided by letting the display frontend engine > do the dma from memory, and then letting it feed the data directly into > the backend unmodified, as the frontend does have deep enough fifo-s. > > Note since u-boot-v2015.01 has been released using the de_be0-lcd0-hdmi > pipeline on sun4i, we need to keep that one around too (unfortunately). > > Signed-off-by: Hans de Goede Merged, thanks! Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com --4rQ9lIe3OahbhU4J--