From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH] serial: sh-sci: Fix receive on SCIFA/SCIFB variants with DMA Date: Fri, 12 Oct 2018 14:19:08 +0200 Message-ID: <20181012121908.sbwsojs7vvhiztbb@ninjato> References: <20181009174158.4476-1-geert+renesas@glider.be> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="buj6bqvqn5q3nvzd" Return-path: Content-Disposition: inline In-Reply-To: <20181009174158.4476-1-geert+renesas@glider.be> Sender: linux-kernel-owner@vger.kernel.org To: Geert Uytterhoeven Cc: Greg Kroah-Hartman , Jiri Slaby , Yoshihiro Shimoda , Ulrich Hecht , Wolfram Sang , linux-serial@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-serial@vger.kernel.org --buj6bqvqn5q3nvzd Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Oct 09, 2018 at 07:41:58PM +0200, Geert Uytterhoeven wrote: > On SCIFA and SCIFB serial ports with DMA support (i.e. some ports on > R-Car Gen2 and RZ/G1 SoCs), receive DMA operations are submitted before > the DMA channel pointer is initialized. Hence this fails, and the > driver tries to fall back to PIO. However, at this early phase in the > initialization sequence, fallback to PIO does not work, leading to a > serial port that cannot receive any data. >=20 > Fix this by calling sci_submit_rx() after initialization of the DMA > channel pointer. >=20 > Reported-by: Jinzai Solution and RVC Test Teams via Yoshihiro Shimoda Brainstorming: keep Shimoda-san's address as is and mention the test teams in the commit message? > Fixes: 2c4ee23530ffc022 ("serial: sh-sci: Postpone DMA release when falli= ng back to PIO") > Signed-off-by: Geert Uytterhoeven Reviewed-by: Wolfram Sang > --- > Reported on r8a7790/lager using SCIFA1 on Debug Serial 1. I hope to test this on Lager this weekend. I am quite sure it will work now, but then we have this formally checked, too. > Tested on r8a7791/koelsch using SCIFA3 on EXIO-B. --buj6bqvqn5q3nvzd Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAlvAkTwACgkQFA3kzBSg KbZkthAAmGR7rsU8Sk45tDzPeEFHpyvkT9eAe7NEJV/V8CzZDW3BxP2mUDSDO0Z9 CWWH0kYPnvirKaGeZtGxJcs3qK4dF/OVkCEWLUs4Z2nv0hNAYmfUt/gBxdQFuqWX jutfgi4EZkVIXvhQtGFU3ahdumsB3LSYy8aNpa9GNpbg0ECSBXgdGTUtA5LZ5H+k NvavVQgVPYaNtT3DXn3FZyZzpUlsxtOtpu4mypjjzWvDlb58F/4zh9E3bkW4cLA0 FjtFpxasFOl34PQVHDnEQmddHSv9GRgRqvaSSvfbmhf9chC1y4ECweXRVBUL1J01 kVUuPEUc0e6ms7OIn67HCsBTDfzN9Mw+bkL1VmX5bIfWkquwBCU+4jMS0Dx9+FZG GudshCXl51V/6MpfxjsVzvS6Phw5sL3ClsiOWphrnCzMwO5Kok9ElPfGqzFFulGO xe+/ys2b8eqiGBNwnYu6artjaPtJkC7XO/l+53OPfnLXqd+U9SfI8HpXJTmHIocf yLE7gFp94BB2vVplrO3PwIRRCVPhz3rV8wBPavfDcU9lJKb74A+qnu/GQJCv8Hqp T4KUqD4hKyBcEGTmU9YQiZJmaxBiNTbrpzT+MR8OnXjphzyoWWs2PMWiedaVIwES 75tnGSiNm9jIhESRavSMYXxu9euM/GaV11c/Nt3Qm5bOLWok8KY= =VFOj -----END PGP SIGNATURE----- --buj6bqvqn5q3nvzd--