GPP_B8 acts as input to the inverter whose output controls PERST#
signal to wifi module. Out of reset, GPP_B8 is configured as
input by default. Since there is no external pull-down on it, this
line is floating and results in PERST# being asserted until ramstage
where the GPIO was originally configured. Because of this the wifi
chip is not ready during the PCIe initialization step. Move the
configuration of GPP_B8 to bootblock so that wifi device is taken out
of reset as early as possible.
BUG=b:64181150,b:62726961
TEST=Verified with warm reboot and suspend-resume stress test that
wifi is still functional.
Change-Id: I68e1bd67499262a17daade72e9a9fd32934a184d
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/20869
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
0767f89be4