From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maxime Ripard Subject: Re: [PATCH v3 01/10] clk: sunxi-ng: Add interface to query or configure MMC timing modes. Date: Tue, 25 Jul 2017 09:32:29 +0200 Message-ID: <20170725073229.fbm7ead455oudftc@flea> References: <20170724135905.28855-1-wens@csie.org> <20170724135905.28855-2-wens@csie.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="wzyrrs3i7h2wwp77" Return-path: Content-Disposition: inline In-Reply-To: <20170724135905.28855-2-wens@csie.org> Sender: linux-clk-owner@vger.kernel.org To: Chen-Yu Tsai Cc: Ulf Hansson , Michael Turquette , Stephen Boyd , Rob Herring , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-mmc@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com List-Id: devicetree@vger.kernel.org --wzyrrs3i7h2wwp77 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jul 24, 2017 at 09:58:56PM +0800, Chen-Yu Tsai wrote: > Starting with the A83T SoC, Allwinner introduced a new timing mode for > its MMC clocks. The new mode changes how the MMC controller sample and > output clocks are delayed to match chip and board specifics. There are > two controls for this, one on the CCU side controlling how the clocks > behave, and one in the MMC controller controlling what inputs to take > and how to route them. >=20 > In the old mode, the MMC clock had 2 child clocks providing the output > and sample clocks, which could be delayed by a number of clock cycles > measured from the MMC clock's parent. >=20 > With the new mode, the 2 delay clocks are no longer active. Instead, > the delays and associated controls are moved into the MMC controller. > The output of the MMC clock is also halved. >=20 > The difference in how things are wired between the modes means that the > clock controls and the MMC controls must match. To achieve this in a > clear, explicit way, we introduce two functions for the MMC driver to > use: one queries the hardware for the current mode set, and the other > allows the MMC driver to request a mode. >=20 > Signed-off-by: Chen-Yu Tsai Acked-by: Maxime Ripard Thanks! Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --wzyrrs3i7h2wwp77 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIcBAEBAgAGBQJZdvQNAAoJEBx+YmzsjxAgo7sP/A7YmHobs5IO97Mpq4X53u7Z XC6NfQLYXxSAidX+g/Uusrt+R6RdAdyuKZdrNq0AuxA5lhLbAAb910IiTOH0vATJ zFQLp3VhpNE2OhyU8eoQyO9OWRNLEVRQrSIj6vwpm1AVYT5sDx8+DCBbLxvnEf7k fafo+tmnQqIU2qgD0yGnDLsOrVTYHotyHmHCigdi4uVxfpa9i4cfYKlycoi7h9YQ 65iZPdFiDf5pvUEVQUDCh8H+b5wik6S/W1DDYEBuWeg7dwdVEZAL1gHRYm4gwgOn 027/Hefy7+WNj6OEiEGas1/bzJ9Y0afK4eWHgzIjiOzeqeaJeGKRmesy+RoeOkOJ CAobLroRSzGzToibhA/8dRNZV9mCmonVOOGWRAwtJz5ght7WN5VXhJaoFQWmphaI AQnlJuby7eEn26IVQ4b/IwiZsDXovphgUH031ND6jXJWo9KT/yHkaEFUm4yS+qPx j3GGfEyyaZ/1oSqI47g2mVrLia8nFRRPLcZSD5Y3a1qxjF0n/q/aD9Be3Xb391Gn N/m7qIJNplHo46KvIM9G6alh6irBjY728438xr2BrSXG1t6oOtz3noBMX9nr/gie ENJGOM6+edKcOEjuBgy7B5xZfLbBcBIEnN3CfImHwUZKSCLNjJhPWTsKk+g4fgHG BNx4jrO48UqdBNxXYu9o =5sjE -----END PGP SIGNATURE----- --wzyrrs3i7h2wwp77--