Add a flash driver for the STM32L4 family.
For write and erase, the code is very similar to other variants
excepted the 'normal' writes need to be perform 2 aligned
32-bit words at a time.
Option bytes are a sligthly easier business since the hardware deals
with the option bytes page preserving and erasing for us.
For the write-protection, the STM32L4 is slightly different from the
other variants. The write-protection granularity is still a 2-kB block
(2kB here) but instead of having a 'bitmap' of the protected blocks, it
defines 2 write-protection ranges (WRP1AR and WRP1BR).
For the EC code base, we are using WRP1AR to protect the Read-Only
regions and WRP1BR to protect the Rollback and RW regions (if they
exist).
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
BRANCH=none
BUG=b:35648258
TEST=On Eve, run 'flashrom -p ec:type=fp -w /tmp/ec.bin'
and 'flashrom -p ec:type=fp --wp-enable --wp-range 0x0 0x20000'
Change-Id: Iaa98c1b4d3b07de2923ac076624bd4601c31a600
Reviewed-on: https://chromium-review.googlesource.com/456711
Commit-Ready: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
d8cbf0dc40