From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932188Ab3FAAak (ORCPT ); Fri, 31 May 2013 20:30:40 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:40956 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755037Ab3FAAad (ORCPT ); Fri, 31 May 2013 20:30:33 -0400 Date: Fri, 31 May 2013 19:30:29 -0500 From: "Philip J. Kelleher" To: axboe@kernel.dk Cc: linux-kernel@vger.kernel.org Subject: [PATCH 4/8] rsxx: Adding EEH check inside cregs timeout. Message-ID: <20130601003029.GE3051@oc6784271780.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-12-10) X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13060100-7606-0000-0000-00000C0D0881 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Philip J Kelleher Unfortunaly, our CPU register path does not do any kind of EEH error checking. So to fix this issue, an ioread32 was added to the CPU register timeout code. This way, the driver can check to see if the timeout was caused by an EEH error or not. This is a dummy read. Signed-off-by: Philip J Kelleher ------------------------------------------------------------------------------- diff -uprN -X linux-block/Documentation/dontdiff linux-block-vanilla/drivers/block/rsxx/cregs.c linux-block/drivers/block/rsxx/cregs.c --- linux-block-vanilla/drivers/block/rsxx/cregs.c 2013-05-31 15:37:27.481079110 -0500 +++ linux-block/drivers/block/rsxx/cregs.c 2013-05-31 16:35:52.306080966 -0500 @@ -431,6 +431,15 @@ static int __issue_creg_rw(struct rsxx_c *hw_stat = completion.creg_status; if (completion.st) { + /* + * This read is needed to verify that there has not been any + * extreme errors that might have occurred, i.e. EEH. The + * function iowrite32 will not detect EEH errors, so it is + * necessary that we recover if such an error is the reason + * for the timeout. This is a dummy read. + */ + ioread32(card->regmap + SCRATCH); + dev_warn(CARD_TO_DEV(card), "creg command failed(%d x%08x)\n", completion.st, addr);