From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: Re: [RFC PATCH 4/4] mmc: sdhci-of-arasan: overwrite enhanced strobe callback Date: Thu, 3 Mar 2016 19:37:17 +0800 Message-ID: <56D821ED.9090203@rock-chips.com> References: <1456972557-7994-1-git-send-email-shawn.lin@rock-chips.com> <1456972613-8159-1-git-send-email-shawn.lin@rock-chips.com> <56D819C4.9080703@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from lucky1.263xmail.com ([211.157.147.131]:42326 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751386AbcCCLhm (ORCPT ); Thu, 3 Mar 2016 06:37:42 -0500 In-Reply-To: <56D819C4.9080703@xilinx.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Michal Simek , Adrian Hunter , Ulf Hansson Cc: shawn.lin@rock-chips.com, shawn.lin@kernel-upstream.org, soren.brinkmann@xilinx.com, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org On 2016/3/3 19:02, Michal Simek wrote: > On 3.3.2016 03:36, Shawn Lin wrote: >> Currently sdhci-arasan 5.1 can support enhanced strobe function, >> but considering the potential requirement in the future for other >> version IP, we don't limit it just for "arasan,sdhci-5.1". Add >> cap-enhanced-strobe in DT to enable the function if we'r sure our >> controller can support it. >> >> Signed-off-by: Shawn Lin >> --- >> >> drivers/mmc/host/sdhci-of-arasan.c | 20 ++++++++++++++++++++ >> 1 file changed, 20 insertions(+) >> >> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c >> index 1e4b5e0..31f3494 100644 >> --- a/drivers/mmc/host/sdhci-of-arasan.c >> +++ b/drivers/mmc/host/sdhci-of-arasan.c >> @@ -24,7 +24,9 @@ >> #include "sdhci-pltfm.h" >> >> #define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c >> +#define SDHCI_ARASAN_VENDOR_REGISTER 0x78 > > I was checking our register map and we even don't have this register > listed as reserved. > It looks like that this will be related to certain SoC and different SoC > can use it different location. > That's why I think this feature and setup should be related to certain > SoC specific compatible string. Hi Michal, I think that is IP version specific because it's inside controller's databook. But I only have a datasheet released by arasan for 5.1 controller, so I didn't know if your databook has this register. And I can't find sdhci spec has a reg to enable this feature either. Looks strange, but maybe you are right: it also related to certain Soc for other sdhci variant drivers. But for sdhci-of-arsan, it more likes to use this register from now on for the future IP version to enable this feature inside the controller register-range. Thanks for checking that. Now, I'm more sure about that we should limit it for 5.1 currently by checking the compatible string. I expect more comments from ulf and adrian about the other part of code until I respin the next version. > > Thanks, > Michal > > > > -- Best Regards Shawn Lin