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36d4ecb153
We copied that delay because it seemed to be necessary on early LM4
chips to avoid glitching the UART. But on current boards (e.g. rambi)
this does not seem to be necessary, and delays boot by 31ms. So,
remove the delay.
BUG=chrome-os-partner:23794
BRANCH=rambi
TEST=boot system; see little to no glitching on EC uart, and system boots ok
hibernate 1; see little to no glitching on EC uart, and system boots ok
Change-Id: I9d4b5927da4282e47e1b09be838104c64f25268c
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/185232
Reviewed-by: Bill Richardson <wfrichar@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.