spi_flash: Differentiate between atomic/manual sequencing

This adds a wrapper function and a Kconfig variable to differentiate
between SPI controllers which use atomic cycle sequencing versus
those where the transaction sequence is controlled manually. Currently
this boils down to x86 vs. non-x86.

Yes, it's hideous. The current API only worked because, for better or
worse, x86 platforms have been homogeneous in this regard since they
started using SPI as an alternative to FWH for boot flash. Now that
we have non-x86 platforms which use general purpose SPI controllers,
we should overhaul the entire SPI infrastructure to be more adaptable.

BUG=none
BRANCH=none
TEST=tested on nyan and link
Signed-off-by: David Hendricks <dhendrix@chromium.org>

Original-Change-Id: If8ccc9400a9d04772a195941a42bc82d5ecc1958
Original-Reviewed-on: https://chromium-review.googlesource.com/195283
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Original-Commit-Queue: David Hendricks <dhendrix@chromium.org>
Original-Tested-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 4170c59d06206667755402712083452da9fcd941)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I54e2d3d9f9a0153a56f7a51b80f6ee6d997ad358
Reviewed-on: http://review.coreboot.org/7828
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

0 files changed, 0 insertions, 0 deletions