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BUG=chrome-os-partner:24370 BRANCH=tot TEST=Power key and keyboard work normally. Signed-off-by: Dave Parker <dparker@chromium.org> Orig-Change-Id: I291ff384ae2fc3e074132330713f0b0c2cc36a76 Reviewed-on: https://chromium-review.googlesource.com/184543 (cherry picked from commit c65f82a5b02cdecf5b62f71ef2e916795f808389) Change-Id: I1cd02e824c97eb5909e7bff68c8ecefc89f52df0 Reviewed-on: https://chromium-review.googlesource.com/185242 Tested-by: Randall Spangler <rspangler@chromium.org> Reviewed-by: Bill Richardson <wfrichar@chromium.org> Commit-Queue: Randall Spangler <rspangler@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.