linux/drivers/mmc
Heiner Kallweit 79ed05e329 mmc: meson-gx: add support for descriptor chain mode
So far a bounce buffer is used to serialize the scatterlist(s).
This overhead can be avoided by switching to descriptor chain mode.
As result the performance is drastically improved. On a Odroid-C2 with
a 128 GB eMMC module raw reads reach 140 MB/s.

Prerequisite for descriptor chain mode is that all scatterlist buffers
are 8 byte aligned for 64-bit DMA. That's not always the case, at least
the brcmfmac SDIO WiFi driver is known to cause problems.

Therefore, for each request, check upfront whether all scatterlist
buffers are 8 byte aligned and fall back to bounce buffer mode if
that's not the case.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
2017-04-24 21:42:21 +02:00
..
core mmc: core: add proper be32 annotation 2017-04-24 21:42:19 +02:00
host mmc: meson-gx: add support for descriptor chain mode 2017-04-24 21:42:21 +02:00
Kconfig mmc: block: Move files to core 2016-12-12 16:30:05 +01:00
Makefile mmc: block: Move files to core 2016-12-12 16:30:05 +01:00