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We have three duplicated ADC read console command, and we are about to have the fourth. Let's consolidate them to a single implementation in common/. Note that we have to add a simple implementation of adc_read_all_channels() for LM4. BUG=chrome-os-partner:18343 TEST=Build all boards TEST=Read single channel TEST=Read all channels BRANCH=None Change-Id: I079c0b33ab6b81a188f309cf99875eb02e9d78a4 Signed-off-by: Vic (Chun-Ju) Yang <victoryang@chromium.org> Reviewed-on: https://chromium-review.googlesource.com/180831
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.