linux-stable.git/include/linux/mmc/host.h, branch v4.16.2

mmc: core: Remove code no longer needed after the switch to blk-mq

2017-12-11T12:05:58+00:00

Remove code no longer needed after the switch to blk-mq.

Signed-off-by: Adrian Hunter 
Acked-by: Linus Walleij 
Tested-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: block: blk-mq: Add support for direct completion

2017-12-11T11:44:35+00:00

For blk-mq, add support for completing requests directly in the ->done
callback. That means that error handling and urgent background operations
must be handled by recovery_work in that case.

Signed-off-by: Adrian Hunter 
Acked-by: Linus Walleij 
Signed-off-by: Ulf Hansson 
Tested-by: Linus Walleij

mmc: core: Add parameter use_blk_mq

2017-12-11T11:44:33+00:00

Until mmc has blk-mq support fully implemented and tested, add a parameter
use_blk_mq, set to true if config option MMC_MQ_DEFAULT is selected, which
it is by default.

Signed-off-by: Adrian Hunter 
Acked-by: Linus Walleij 
Signed-off-by: Ulf Hansson 
Tested-by: Linus Walleij

mmc: parse new binding for eMMC fixed driver type

2017-10-30T10:50:38+00:00

Parse the new binding and store it in the host struct after doing some
sanity checks. The code is designed to support fixed SD driver type if
we ever need that.

Signed-off-by: Wolfram Sang 
Reviewed-by: Simon Horman 
Signed-off-by: Ulf Hansson

mmc: core: Add support for handling CQE requests

2017-10-30T10:45:50+00:00

Add core support for handling CQE requests, including starting, completing
and recovering.

Signed-off-by: Adrian Hunter 
Reviewed-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: core: Introduce host claiming by context

2017-10-30T10:45:49+00:00

Currently the host can be claimed by a task.  Change this so that the host
can be claimed by a context that may or may not be a task.  This provides
for the host to be claimed by a block driver queue to support blk-mq, while
maintaining compatibility with the existing use of mmc_claim_host().

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson

mmc: Delete bounce buffer handling

2017-10-04T08:22:55+00:00

In may, Steven sent a patch deleting the bounce buffer handling
and the CONFIG_MMC_BLOCK_BOUNCE option.

I chose the less invasive path of making it a runtime config
option, and we merged that successfully for kernel v4.12.

The code is however just standing in the way and taking up
space for seemingly no gain on any systems in wide use today.

Pierre says the code was there to improve speed on TI SDHCI
controllers on certain HP laptops and possibly some Ricoh
controllers as well. Early SDHCI controllers lacked the
scatter-gather feature, which made software bounce buffers
a significant speed boost.

We are clearly talking about the list of SDHCI PCI-based
MMC/SD card readers found in the pci_ids[] list in
drivers/mmc/host/sdhci-pci-core.c.

The TI SDHCI derivative is not supported by the upstream
kernel. This leaves the Ricoh.

What we can however notice is that the x86 defconfigs in the
kernel did not enable CONFIG_MMC_BLOCK_BOUNCE option, which
means that any such laptop would have to have a custom
configured kernel to actually take advantage of this
bounce buffer speed-up. It simply seems like there was
a speed optimization for the Ricoh controllers that noone
was using. (I have not checked the distro defconfigs but
I am pretty sure the situation is the same there.)

Bounce buffers increased performance on the OMAP HSMMC
at one point, and was part of the original submission in
commit a45c6cb81647 ("[ARM] 5369/1: omap mmc: Add new
   omap hsmmc controller for 2430 and 34xx, v3")

This optimization was removed in
commit 0ccd76d4c236 ("omap_hsmmc: Implement scatter-gather
   emulation")
which found that scatter-gather emulation provided even
better performance.

The same was introduced for SDHCI in
commit 2134a922c6e7 ("sdhci: scatter-gather (ADMA) support")

I am pretty positively convinced that software
scatter-gather emulation will do for any host controller what
the bounce buffers were doing. Essentially, the bounce buffer
was a reimplementation of software scatter-gather-emulation in
the MMC subsystem, and it should be done away with.

Cc: Pierre Ossman 
Cc: Juha Yrjola 
Cc: Steven J. Hill 
Cc: Shawn Lin 
Cc: Adrian Hunter 
Suggested-by: Steven J. Hill 
Suggested-by: Shawn Lin 
Signed-off-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: host: Add CQE interface

2017-08-30T13:03:33+00:00

Add CQE host operations, capabilities, and host members.

Signed-off-by: Adrian Hunter 
Signed-off-by: Ulf Hansson

mmc: core: Remove unused MMC_CAP2_PACKED_CMD

2017-08-30T12:02:00+00:00

Packed commands support was removed but some bits got left behind. Remove
them.

Signed-off-by: Adrian Hunter 
Reviewed-by: Linus Walleij 
Signed-off-by: Ulf Hansson

mmc: core: remove check of host->removed for rescan routine

2017-08-30T12:01:33+00:00

The intention of this check was to prevent the conflict between
hotplug and removing driver for whatever reason. Currently it
doesn't improve anything and the following rescan process could
still saftly perform the scan flow. So these code seems pointless
now and let's remove them.

Signed-off-by: Shawn Lin 
Signed-off-by: Ulf Hansson