From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian Hunter Subject: Re: mmc0: Invalid maximum block size, assuming 512 bytes Date: Tue, 2 Feb 2016 10:58:56 +0200 Message-ID: <56B06FD0.6000109@intel.com> References: <569E575A.5070401@free.fr> <569EE03F.9090008@rock-chips.com> <56A0F2A1.3060805@free.fr> <56A18EFE.6000900@rock-chips.com> <56A1D791.9010803@free.fr> <56AFCEE0.1090005@free.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mga09.intel.com ([134.134.136.24]:45380 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753962AbcBBJDJ (ORCPT ); Tue, 2 Feb 2016 04:03:09 -0500 In-Reply-To: <56AFCEE0.1090005@free.fr> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Mason , linux-mmc Cc: Shawn Lin , Michal Simek , Soren Brinkmann , Suman Tripathi , Arnd Bergmann , Ulf Hansson , Sebastian Frias On 01/02/16 23:32, Mason wrote: > On 22/01/2016 08:17, Mason wrote: > >> On 22/01/2016 03:07, Shawn Lin wrote: >> >>> On 2016/1/21 23:00, Mason wrote: >>> >>>> So that means I have to write code in >>>> drivers/mmc/host/sdhci-of-arasan.c correct? >>> >>> It depends. If you think 512 block size if okay for you, leave it alone. >>> Otherwise, add it in drivers/mmc/host/sdhci-of-arasan.c :) >> >> When I measured the read/write throughput to an attached >> SD card, I got around 16 MB/s, and I thought raising the >> block size might help with throughput? >> >> I'll test and report back. > > Haven't had time to test yet, but I wanted to ask experienced > folks what to expect when raising the block size from 512 to > 2048 bytes? mmc block driver sets block size to 512. What you are looking at is maximum block size. SDIO uses bigger block sizes, so it is useful for that.