mirror of
https://github.com/Telecominfraproject/OpenCellular.git
synced 2025-12-28 10:45:22 +00:00
7e78087a91
This fixes a bug in which after a sysjump, the sleep_mask is reset, and the EC is allowed to go into a low power mode even though the AP is still running. This causes numerous problems, must notable of which is that a flashrom write fails with an EC protocol mismatch error. BUG=chrome-os-partner:23645 BRANCH=none TEST=Execute a flashrom write and make sure the system does not use the low power code immediately after. Change-Id: I4d50282da0c5ba5b6488ed14a267a4d8cafe09a7 Signed-off-by: Alec Berg <alecaberg@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/174943 Reviewed-by: Randall Spangler <rspangler@chromium.org> Reviewed-by: Vincent Palatin <vpalatin@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.