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When using a "non-servo" debug dongle or integrated FTDI chip to flash a STM32 microcontroller, add the option to toggle the reset of the microcontroller if the control exists. This was not done for the original Toad version because it cannot control the reset line, but now Firefly, Zinger, Fruitpie debug interfaces can do it. Signed-off-by: Vincent Palatin <vpalatin@chromium.org> BRANCH=none BUG=none TEST=./util/flash_ec --board=zinger Change-Id: Ia21e3b3403e56b4c0797582659d9a3a0c26bb8bb Reviewed-on: https://chromium-review.googlesource.com/197050 Tested-by: Vincent Palatin <vpalatin@chromium.org> Reviewed-by: Todd Broch <tbroch@chromium.org> Commit-Queue: 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.