Hi Jaehoon, It is in a draft eMMC5.1 spec. I believe the official eMMC5.1 spec will be released soon. Thanks Chuanxiao > -----Original Message----- > From: linux-mmc-owner@xxxxxxxxxxxxxxx > [mailto:linux-mmc-owner@xxxxxxxxxxxxxxx] On Behalf Of Jaehoon Chung > Sent: Monday, December 22, 2014 12:56 PM > To: Dong, Chuanxiao; linux-mmc@xxxxxxxxxxxxxxx > Subject: Re: [RFC PATCH 0/5]mmc: Soft Command queue implementation for > eMMC5.1 device > > 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(-) > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body > of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
