usb_updater: separate image updates and resets, add restore image option
With the upcoming availability of the downloaded header corruption,
there needs to be a mechanism for usb_updater to restore the corrupted
header, so that the downloaded code can run right away.
This patch separates image download and reset functionality. Download
happens as before, and the UPGRADE_DONE PDU is sent immediately once
image transfer completes. This puts the receive state machine into the
idle state and allows to send other commands.
The reset function is different for the target supporting protocol
versions 5 and above. The only command version 5 recognizes is the
indirect reboot command (the UPGRADE_DONE PDU sent the second time in
a row). For protocol version 6 and above the reset could be immediate
or posted, and for targets running RW version 19 or above the command
to restore the corrupted header is required.
When running on the target the command to restore the corrupted header
would be generated by the AP firmware on the reboot.
BRANCH=cr50
BUG=b:35580805
TEST=with the next patch of the series applied observed the corrupted
header properly restored and the device rebooted.
Change-Id: If87c12fe8578cd6f1b4beed6d113471356f6b6c2
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/457677
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed
