From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaehoon Chung Subject: Re: [RFC PATCH 0/5]mmc: Soft Command queue implementation for eMMC5.1 device Date: Mon, 22 Dec 2014 13:55:41 +0900 Message-ID: <5497A44D.6030000@samsung.com> References: <20141219080442.GA3775@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mailout3.samsung.com ([203.254.224.33]:46366 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753813AbaLVEzp (ORCPT ); Sun, 21 Dec 2014 23:55:45 -0500 Received: from epcpsbgr1.samsung.com (u141.gpu120.samsung.co.kr [203.254.230.141]) by mailout3.samsung.com (Oracle Communications Messaging Server 7u4-24.01 (7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NGY00400WCU0K50@mailout3.samsung.com> for linux-mmc@vger.kernel.org; Mon, 22 Dec 2014 13:55:42 +0900 (KST) In-reply-to: <20141219080442.GA3775@intel.com> Sender: linux-mmc-owner@vger.kernel.org List-Id: linux-mmc@vger.kernel.org To: Chuanxiao Dong , linux-mmc@vger.kernel.org Hi, Chuanxiao. Was it published for the eMMC5.1 spec? Best Regards, Jaehoon Chung On 12/19/2014 05:04 PM, Chuanxiao Dong wrote: > Hello, > > Seems community already have some implementation for the eMMC5.1 device command > queue feature, but that require the eMMC host controller to support CMDQ. In my > platform, I don't have this kind of eMMC host controller but I have a > Samsung eMMC5.1 device which can support the Command queue. > > With this limitation, I have to let eMMC host controller to manually send the > CMD44/45/13/46/47. So in this way, more commands are needed for an I/O request, > more interrupts/schedule are needed in driver. > > Even this way have some more software overhead, but it can still use the eMMC5.1 > device Command queue feature. After test with the iozone command: > "iozone -zec -t 4 -i0 -i2 -F iozonefile1 iozonefile2 iozonefile3 iozonefile4 -+n > -I -r 4k -s 500m -O -R -+r -+D" to test random performance, I saw a performance > improvment for random read on my eMMC5.1 device: > > Random read > SW CMDQ: 5544.6 > Normal Read: 3993.05 > > So I want to send this serial patches as RFC patch for reviewing > > > Chuanxiao Dong (5): > mmc: replace sbc to precmd and add postcmd > mmc: host: add runtime PM for host class dev > mmc: queue: change mqrq_cur and mqrq_pre to mq qdepth > mmc: core: add support for CMDQ feature in MMC Core stack > mmc: sdhci: add SW CMDQ support for CHT SDHCI host > > drivers/mmc/card/block.c | 538 ++++++++++++++++++++++++++++++++++++++--- > drivers/mmc/card/queue.c | 213 ++++++++-------- > drivers/mmc/card/queue.h | 14 +- > drivers/mmc/core/core.c | 78 +++++- > drivers/mmc/core/host.c | 14 ++ > drivers/mmc/core/mmc.c | 43 +++- > drivers/mmc/host/dw_mmc.c | 8 +- > drivers/mmc/host/mmci.c | 14 +- > drivers/mmc/host/omap_hsmmc.c | 18 +- > drivers/mmc/host/sdhci-acpi.c | 1 - > drivers/mmc/host/sdhci-pci.c | 1 - > drivers/mmc/host/sdhci.c | 137 +++++++++-- > include/linux/mmc/card.h | 3 + > include/linux/mmc/core.h | 5 +- > include/linux/mmc/host.h | 5 + > include/linux/mmc/mmc.h | 21 ++ > include/linux/mmc/pm.h | 1 + > include/linux/mmc/sdhci.h | 1 + > 18 files changed, 909 insertions(+), 206 deletions(-) >