[U-Boot] [PATCH 0/3] Rpi: Add support for second sd host controller

Alexander Graf agraf at suse.de
Tue Jan 16 13:46:35 UTC 2018


The Raspberry Pi (bcm283x SoC) family contains 2 IP blocks to drive SD
peripherals: A pretty standard SDHCI one called iProc and a home grown
one called "sdhost".

When driving U-Boot by the same device tree that we use for Linux, we
end up in situations where only the "sdhost" device is available for use.
In those situations, current U-Boot can simply not drive the SD card,
because the device tree disables the SDHCI device.

This patch set also adds support for pinmuxing the SD devices properly
to their respective pins. This is necessary because the RPi firmware
doesn't mux the SD pins according to the device tree but instead expects
the payload (usually Linux, U-Boot for us) to do that.

With this patch set, I can successfully use U-Boot on a RPi3 Compute
Module with CONFIG_OF_BOARD=y and a device tree generated by the RPi
firmware (plus a few overlays in config.txt for vc4, serial, etc).

Alexander Graf (3):
  bcm2835_gpio: Add support for pinmux
  mmc: Add bcm2835 sdhost controller
  mmc: bcm2835_sdhci: Add pinmux support

 arch/arm/mach-bcm283x/include/mach/gpio.h |    1 +
 drivers/gpio/bcm2835_gpio.c               |   40 ++
 drivers/mmc/Kconfig                       |   14 +
 drivers/mmc/Makefile                      |    1 +
 drivers/mmc/bcm2835_sdhci.c               |   11 +
 drivers/mmc/bcm2835_sdhost.c              | 1000 +++++++++++++++++++++++++++++
 6 files changed, 1067 insertions(+)
 create mode 100644 drivers/mmc/bcm2835_sdhost.c

-- 
2.12.3



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