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BUG=chrome-os-partner:24876 BRANCH=None TEST=Suspend with a USB keyboard attached. On the EC console, 'gpioget pp5000_en' should be 1. Change-Id: Ic4ec175e2a5b51c433143e61e417d2171f1f99f2 Original-Change-Id: Ie7850617befa32dd2c2146ef23d18252ef6ea4a4 Signed-off-by: Dave Parker <dparker@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/186673 Reviewed-by: Randall Spangler <rspangler@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/192193
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.