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1006187c61
This is an initial version of power sequencing for the rambi rev.1
boards. It has a workaround for a rev.1 board problem; this requires
turning on PP5000 early.
BUG=chrome-os-partner:22895
BRANCH=none
TEST=AP should power on to S0 (PLTRST# deasserts) automatically when EC boots
Then 'apshutdown' should drag it back to G3.
Then 'powerbtn' should take it back to S0.
Change-Id: Id9bc6fe9b55fce3eb46ce1265891724ec7a4ae20
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/172675
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
In the most general case, the flash layout looks something like this: +---------------------+ | Reserved for EC use | +---------------------+ +---------------------+ | Vblock B | +---------------------+ | RW firmware B | +---------------------+ +---------------------+ | Vblock A | +---------------------+ | RW firmware A | +---------------------+ +---------------------+ | FMAP | +---------------------+ | Public root key | +---------------------+ | Read-only firmware | +---------------------+ BIOS firmware (and kernel) put the vblock info at the start of each image where it's easy to find. The Blizzard EC expects the firmware vector table to come first, so we have to put the vblock at the end. This means we have to know where to look for it, but that's built into the FMAP and the RO firmware anyway, so that's not an issue. The RO firmware doesn't need a vblock of course, but it does need some reserved space for vboot-related things. Using SHA256/RSA4096, the vblock is 2468 bytes (0x9a4), while the public root key is 1064 bytes (0x428) and the current FMAP is 644 bytes (0x284). If we reserve 4K at the top of each FW image, that should give us plenty of room for vboot-related stuff.