tpm2: handle failures more gracefully

When trying to bring up a device with a malfunctioning TPM2 chip, the
driver currently gets stuck waiting for SPI flow control, causing
bricked devices.

This patch puts a 100 ms cap on the waiting time - this should be
enough even for a longest NVRAM save operation which could be under
way on the TPM device.

BRANCH=gru
BUG=chrome-os-partner:59807
TEST=with a matching change in depthcharge, now a gru with corrupted
     SPI TPM comes up to the recovery screen (it was not showing signs
     of life before this change).

Change-Id: I63ef5dde8dddd9afeae91e396c157a1a37d47c80
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://review.coreboot.org/17898
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins)

0 files changed, 0 insertions, 0 deletions