From mboxrd@z Thu Jan 1 00:00:00 1970 From: Przemyslaw Marczak Date: Mon, 02 Sep 2013 16:16:52 +0200 Subject: [U-Boot] [PATCH] mmc:sdhci: Fix card ready status timeout. In-Reply-To: <521EBCF5.3020007@samsung.com> References: <1377708592-16702-1-git-send-email-p.marczak@samsung.com> <521EBCF5.3020007@samsung.com> Message-ID: <52249DD4.3090802@samsung.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 08/29/2013 05:16 AM, Jaehoon Chung wrote: > Hi Przemyslaw, > > Could you give me the test-case? > I want to test this problem. > > On 08/29/2013 01:49 AM, Przemyslaw Marczak wrote: >> According to JEDEC eMMC specification, after data transfer >> (multiple or single block) host must wait for card ready >> status. This is done by waiting for command and data lines >> to be at idle state after transfer. JEDEC does not specify >> maximum timeout. >> >> Before this change max timeout was 10 ms but in case of UMS >> - when system do multiple read/write operations on random >> card blocks - timeout causes I/O errors. >> The timeout has been increased to 200ms after data transfer. >> For other transfers it stays unchanged. >> >> Tested on Goni and Trats. >> >> Signed-off-by: Przemyslaw Marczak >> Cc: Pantelis Antoniou Hello, You can ease reproduce this problem by typing "ums" on prompt(Trats). If you are using Goni (without ums config), the problem is hard to reproduce in this case. Sometimes read one block from mmc just after start causes error and then you can see information "Controller never released inhibit bit(s)". Patch will be completed with some code comment. Thank you -- Przemyslaw Marczak Samsung R&D Institute Poland Samsung Electronics p.marczak at samsung.com