Revision 5ea47691bd99e1100707ec63364aff72324e2af4 authored by Daniel Drake on 20 March 2019, 06:36:53 UTC, committed by Ulf Hansson on 21 March 2019, 10:19:06 UTC
Setting max_blk_count to 1 here was causing the mmc block layer
to always use the MMC_READ_SINGLE_BLOCK command here, which the
driver does not DMA-accelerate.
Drop the max_blk_ settings here. The mmc host defaults suffice,
along with the max_segs and max_seg_size settings, which I have
now documented in more detail.
Now each MMC command reads 4 512-byte blocks, using DMA instead of
PIO. On my SD card, this increases read performance (measured with dd)
from 167kb/sec to 4.6mb/sec.
Link: http://lkml.kernel.org/r/CAD8Lp47L5T3jnAjBiPs1cQ+yFA3L6LJtgFvMETnBrY63-Zdi2g@mail.gmail.com
Signed-off-by: Daniel Drake <drake@endlessm.com>
Reviewed-by: Oleksij Rempel <linux@rempel-privat.de>
Fixes: c5413ad815a6 ("mmc: add new Alcor Micro Cardreader SD/MMC driver")
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
1 parent 031d2cc
Kconfig
menu "SOC (System On Chip) specific Drivers"
source "drivers/soc/actions/Kconfig"
source "drivers/soc/amlogic/Kconfig"
source "drivers/soc/atmel/Kconfig"
source "drivers/soc/bcm/Kconfig"
source "drivers/soc/fsl/Kconfig"
source "drivers/soc/imx/Kconfig"
source "drivers/soc/mediatek/Kconfig"
source "drivers/soc/qcom/Kconfig"
source "drivers/soc/renesas/Kconfig"
source "drivers/soc/rockchip/Kconfig"
source "drivers/soc/samsung/Kconfig"
source "drivers/soc/sunxi/Kconfig"
source "drivers/soc/tegra/Kconfig"
source "drivers/soc/ti/Kconfig"
source "drivers/soc/ux500/Kconfig"
source "drivers/soc/versatile/Kconfig"
source "drivers/soc/xilinx/Kconfig"
source "drivers/soc/zte/Kconfig"
endmenu
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