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BUG=chrome-os-partner:25655 BRANCH=None TEST=Verify WLAN_OFF_L = 1 and GPIO_PP3300_WLAN_EN = 1 in suspend. Change-Id: I06df0a7c629e554fad110a9c3611d84035100af3 Original-Change-Id: I6d60fe78d51a1b6ef16b3e1df242025e927aa7d1 Signed-off-by: Dave Parker <dparker@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/187994 Reviewed-by: Randall Spangler <rspangler@chromium.org> Reviewed-by: Bernie Thompson <bhthompson@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/192192
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.