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8eacb8ffe2
Due to power topology, PP5000 needs to be enabled as soon after
PP3300_DSW as possible. Since PP3300_DSW is what powers the EC, the
EC needs to turn on PP5000 by default and leave it on.
BUG=chrome-os-partner:23673
BRANCH=none
TEST=reboot ap-off (this boots the EC without doing AP power sequencing)
gpioget -> shows PP5000_EN=1, PP5000_GOOD=1
Change-Id: I5d493877d330b2543a493f8a2f3411003d5964ca
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/174989
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.