rk3288: Re-write spi_xfer() to support full duplex

This change re-writes the spi_xfer() function to support full-duplex
transfers.

Even though the code looks much different, the same basic algorithm
for setting up the transfer is used. The main difference is that
reads from rxdr and writes to txdr occur simultaneously and accounting
is more complicated, so I separated the higher-level accounting
portion from the low-level FIFO handling portion to simplify things.

BUG=chrome-os-partner:31850
BRANCH=none
TEST=Loaded content from SPI ROM fine, needs testing w/ EC

Change-Id: Ic109a02daf52ba694b63a73fec1a72b3c5c0fd71
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 6a14f5ff8ed04d62e8de6ad2f468b763ffb8213c
Original-Signed-off-by: David Hendricks <dhendrix@chromium.org>
Original-Change-Id: I33d2f5179360baf94627c86b57d12f032897caf5
Original-Reviewed-on: https://chromium-review.googlesource.com/218881
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: http://review.coreboot.org/9338
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

0 files changed, 0 insertions, 0 deletions