This adds a simple driver for the BCM2835's SD controller.
Workarounds are implemented for:
* Register writes can't be too close to each-other in time, or they will
be lost.
* Register accesses must all be 32-bit, so implement custom accessors.
This code was extracted from:
git://github.com/gonzoua/u-boot-pi.git master
which was created by Oleksandr Tymoshenko.
Portions of the code there were obviously based on the Linux kernel at:
git://github.com/raspberrypi/linux.git rpi-3.6.y
commit f5b930b "Main bcm2708 linux port" signed-off-by Dom Cobley.
swarren changed the following for upstream:
* Removed hack udelay()s in bcm2835_sdhci_raw_writel(); setting
SDHCI_QUIRK_WAIT_SEND_CMD appears to solve the issues.
* Remove register logging from read*/write* functions.
* Sort out confusion with min/max_freq values passed to add_sdhci().
* Use more descriptive variable names and calculations in IO accessors.
* Simplified and commented twoticks_delay calculation.
* checkpatch fixes.
Cc: Andy Fleming <afleming@gmail.com>
Signed-off-by: Oleksandr Tymoshenko <gonzo@bluezbox.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Andy Fleming <afleming@gmail.com>
Commit 86c6326 "ARM: arm1176: enable instruction cache in
arch_cpu_init()" defined arch_cpu_init() in a file that is shared across
all arm1176 SoCs. tnetv107x already implemented this function, which
caused linking to break. Move the new conflicting arch_cpu_init() into
arm1176/bcm2835/init.c so that it doesn't conflict; grep indicates this
function is usually defined at the SoC-level, not the CPU-level, at least
for ARM.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Marek Vasut <marex@denx.de>
This SoC is used in the Raspberry Pi, for example.
For more details, see:
http://www.broadcom.com/products/BCM2835http://www.raspberrypi.org/wp-content/uploads/2012/02/BCM2835-ARM-Peripherals.pdf.
Initial support is enough to boot to a serial console, execute a minimal
set of U-Boot commands, download data over a serial port, and boot a
Linux kernel. No storage or network drivers are implemented.
GPIO driver originally by Vikram Narayanan <vikram186@gmail.com>
with many fixes from myself.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Stephen Warren
Fabio Estevam
Peter Tyser
wdenk