mmc: Soft Command queue implementation for eMMC5.1 device

Here are V2 version of eMMC5.1 soft command queue patches.

Performance data captured by iozone command shown it has improvment to both random read and random write. The command used is:
iozone -zec -t 4 -i0 -i2 -F iozonefile1 iozonefile2 iozonefile3 iozonefile4 -+n -I -r 4k -s 500m -O -R -+r -+D

Without CMDQ With CMDQ
Random read 5074.91 7916.06
Random write 1354.69 1444.52

Changes in V2:
1. not to send CMD13 during CMD46/47 is executing.
2. added a timer in case the data never complete for CMD46/47

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
mmc: sdhci: add SW CMDQ support for SDHCI host

 drivers/mmc/card/block.c      |  561 ++++++++++++++++++++++++++++++++++++++---
 drivers/mmc/card/queue.c      |  224 ++++++++--------
 drivers/mmc/card/queue.h      |   14 +-
 drivers/mmc/core/core.c       |   81 +++++-
 drivers/mmc/core/host.c       |   13 +
 drivers/mmc/core/mmc.c        |   37 ++-
 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      |  178 +++++++++++--
 drivers/mmc/host/sdhci.h      |    2 +
 include/linux/mmc/card.h      |    3 +
 include/linux/mmc/core.h      |    5 +-
 include/linux/mmc/host.h      |    4 +
 include/linux/mmc/mmc.h       |   21 ++
 include/linux/mmc/pm.h        |    1 +
 18 files changed, 980 insertions(+), 206 deletions(-)

1.7.10.4