From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pawel Moll Subject: Re: [PATCH] mmc: mmci: Add new VE MMCI variant Date: Thu, 24 Jan 2013 12:36:08 +0000 Message-ID: <1359030968.26878.46.camel@hornet> References: <1355499526-13790-1-git-send-email-pawel.moll@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Return-path: Received: from service87.mimecast.com ([91.220.42.44]:44506 "EHLO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753272Ab3AXMgM convert rfc822-to-8bit (ORCPT ); Thu, 24 Jan 2013 07:36:12 -0500 In-Reply-To: Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Ulf Hansson Cc: Chris Ball , "linux-mmc@vger.kernel.org" , Russell King , Ulf Hansson , Linus Walleij Hello Ulf, On Fri, 2012-12-21 at 11:05 +0000, Ulf Hansson wrote: > On 14 December 2012 16:38, Pawel Moll wrote: > > The Versatile Express IOFPGA as shipped on VECD 5.0 (bitfiles v108/208 > > and v116/216) contains a modified version of the PL180 MMCI, with > > PeriphID Configuration value changed to 0x2. > > > > This version adds an optional "hardware flow control" feature. When > > enabled MMC card clock will be automatically disabled when FIFO is > > about to over/underflow and re-enabled once the host retrieved some > > data. This makes the controller immune to over/underrun errors caused > > by big interrupt handling latencies. > > > > This patch adds relevant device variant in the driver. > > > > Signed-off-by: Pawel Moll > So enabling this in the variant will also effect how the clock is > being set/gated when the clock freq is 0. > > Please have a look at "mmc: mmci: Gate the clock when freq is 0", a > patch I sent out as of 12 dec. > That patch is using the power register to gate the clock. Will that > work with this new version of the PL180 as well? If not, that patch > must be reworked. I'm not quite sure what you meant here, but I see that v2 of your patch does whatever it is supposed to do to ST variants only, so I guess your objections don't apply any more? Cheers! Pawel