[RFC 0/5] replace sdhci-bcm2835 with bcm2835-mmc

Piotr Król piotr.krol at 3mdeb.com
Tue Oct 28 17:00:10 PDT 2014

Hi all,
this patch series introduce bcm2835-mmc driver, which is used in Raspberry Pi
Foundation kernel. It also adds support for slave_sg transfer mode in
bcm2835-dma driver which is used by bcm2835-mmc to decrease CPU utilization.
This driver significantly improves throughput and system CPU utilization in
comparison with sdhci-bcm2835. On my Kingston SDC10/8GB I have ~11MB/s writes
with 15s of sys CPU load, instead of ~700KB/s and 43s of sys CPU utilization.

Almost all code coming from raspberrypi.org, so I'm looking for feedback about
missing/broken stuff and things that should be redesigned.

 Documentation/devicetree/bindings/mmc/brcm,bcm2835-mmc.txt |   23 +++
 arch/arm/boot/dts/bcm2835-rpi-b.dts                        |    2 +-
 arch/arm/boot/dts/bcm2835.dtsi                             |   13 +-
 arch/arm/configs/bcm2835_defconfig                         |    9 +-
 drivers/dma/bcm2835-dma.c                                  |  210 +++++++++++++++++++++++--
 drivers/mmc/host/Kconfig                                   |   29 ++++
 drivers/mmc/host/Makefile                                  |    1 +
 drivers/mmc/host/bcm2835-mmc.c                             | 1449 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 8 files changed, 1716 insertions(+), 20 deletions(-)

[RFC 1/5] bcm2835-mmc: driver for Arasan eMMC IP
[RFC 2/5] dt: bcm2835-mmc bindings documentation
[RFC 3/5] dt: bcm2835: add mmc node
[RFC 4/5] bcm2835-dma: add support for slave_sg transfer mode
[RFC 5/5] bcm2835_defconfig: use bcm2835-mmc instead sdhci-bcm2835

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