From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Cohen Subject: Re: [RFC/PATCH 0/2] mmc: sdhci: Workaround Intel Merrifield issue for HS200 Date: Thu, 19 Dec 2013 19:25:16 -0800 Message-ID: <20131220032516.GB19320@psi-dev26.jf.intel.com> References: <1383069507-27574-1-git-send-email-david.a.cohen@linux.intel.com> <5282A255.5090904@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Dong Aisheng Cc: Chris Ball , Adrian Hunter , gregkh@linuxfoundation.org, "linux-mmc@vger.kernel.org" , "linux-kernel@vger.kernel.org" , chuanxiao.dong@intel.com List-Id: linux-mmc@vger.kernel.org On Fri, Dec 20, 2013 at 11:00:23AM +0800, Dong Aisheng wrote: > On Wed, Nov 13, 2013 at 5:49 AM, David Cohen > wrote: > > On 10/29/2013 10:58 AM, David Cohen wrote: > >> > >> Hi, > >> > >> SDHCI used to work well on Intel Merrifield until this patch was applied: > >> > >> commit 156e14b126ffb6f040bc6f1aff3c51077e42a744 > >> Author: Giuseppe CAVALLARO > >> Date: Wed Jun 12 08:16:38 2013 +0200 > >> > >> mmc: sdhci: fix caps2 for HS200 > >> > >> Although the HC supports HS200 (eMMC) the caps2 are always zero; this > >> means there's no way to use the super speed mode (when init the > >> card). > >> > >> If the HC support SDR104, for SD3.0, so it also supports HS200 for > >> eMMC > >> and this patch just sets the MMC_CAP2_HS200 in the host caps2 field. > >> > >> Looks like there is a hw issue with unknown root cause so far. > >> > >> Is it acceptable to have the quirk I'm proposing to workaround the issue? > > > > > > Ping. Any comments here? > > > > Chris, > Can you pick this one? > IMX also needs this quirk for imx6q/dl since it can not meet HS200 > timing requirement. > > > David, > Is the unkonwn hw issue in your patch #2 resolved now? > If yes, you may not need this quirk. > I could resend it with your sign-off with IMX patches. Merrifield still needs this quirk to not break MMC support. This quirk could be applied to 3.13-rc (since merrifield was added to sdhci-pci.c on 3.13-rc1). Br, David > > Regards > Dong Aisheng > > > Br, David Cohen > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/