From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaehoon Chung Subject: Re: [PATCH v3] mmc: support BKOPS feature for eMMC Date: Wed, 30 Nov 2011 13:09:56 +0900 Message-ID: <4ED5AC94.9020609@samsung.com> References: <4EC45A39.5030706@samsung.com> <4ED4CE04.4070403@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mailout4.samsung.com ([203.254.224.34]:29663 "EHLO mailout4.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751996Ab1K3EKB (ORCPT ); Tue, 29 Nov 2011 23:10:01 -0500 Received: from epcpsbgm1.samsung.com (mailout4.samsung.com [203.254.224.34]) by mailout4.samsung.com (Oracle Communications Messaging Exchange Server 7u4-19.01 64bit (built Sep 7 2010)) with ESMTP id <0LVG00FBMGWNDGJ0@mailout4.samsung.com> for linux-mmc@vger.kernel.org; Wed, 30 Nov 2011 13:09:59 +0900 (KST) Received: from [165.213.219.108] by mmp1.samsung.com (Oracle Communications Messaging Exchange Server 7u4-19.01 64bit (built Sep 7 2010)) with ESMTPA id <0LVG00KSTGWM7MV0@mmp1.samsung.com> for linux-mmc@vger.kernel.org; Wed, 30 Nov 2011 13:09:59 +0900 (KST) In-reply-to: <4ED4CE04.4070403@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Adrian Hunter Cc: Jaehoon Chung , linux-mmc , Chris Ball , Kyungmin Park , Hanumath Prasad , Per Forlin , Sebastian Rasmussen , "Dong, Chuanxiao" , "svenkatr@ti.com" Hi Adrian. On 11/29/2011 09:20 PM, Adrian Hunter wrote: > On 17/11/11 02:50, Jaehoon Chung wrote: >> Enable eMMC background operations (BKOPS) feature. >> >> If URGENT_BKOPS is set after a response, note that BKOPS >> are required. After all I/O requests are finished, run >> BKOPS if required. Should read/write operations be requested >> during BKOPS, first issue HPI to interrupt the ongoing BKOPS >> and then service the request. >> >> If you want to enable this feature, set MMC_CAP2_BKOPS. >> >> Future considerations >> * Check BKOPS_LEVEL=1 and start BKOPS in a preventive manner. >> * Interrupt ongoing BKOPS before powering off the card. >> >> Signed-off-by: Jaehoon Chung >> Signed-off-by: Kyungmin Park >> CC: Hanumath Prasad >> --- >> Changelog V3: >> - move the bkops setting's location in mmc_blk_issue_rw_rq >> - modify condition checking >> - bkops_en is assigned ext_csd[EXT_CSD_BKOPS_EN] instead of "1" >> - remove the unused code >> - change pr_debug instead of pr_warn in mmc_send_hpi_cmd >> - Add the Future consideration suggested by Per >> >> Changelog V2: >> - Use EXCEPTION_STATUS instead of URGENT_BKOPS >> - Add function to check Exception_status(for eMMC4.5) >> - remove unnecessary code. >> > > The main problem with bkops is: > > If the status is at level 3 ("critical"), some operations > may extend beyond their original timeouts due to maintenance > operations which cannot be delayed anymore. > > This means: > > 1. at level 3 either bkops are run or the timeout of the next > (data?) operation is extended > > 2. at level 3 either the bkops must not be interrupted or the > level must be rechecked after interruption and bkops run again > if the level is still 3 Thanks for your comment..I will consider to solve this problem. Best Regards, Jaehoon Chung > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >