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2 commits

Author SHA1 Message Date
Stephen Warren
5eaa215607 ARM: bcm2835: fix get_timer() to return ms
Apparently, CONFIG_SYS_HZ must be 1000. Change this, and fix the timer
driver to conform to this.

Have the timer implementation export a custom API get_timer_us() for use
by the BCM2835 MMC API, which needs us resolution for a HW workaround.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
2013-04-04 08:14:54 +02:00
Stephen Warren
9a4fbe4fbd mmc: add bcm2835 driver
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>
2013-03-20 15:31:25 +01:00