mb/google/brya: Fix brya0 WWAN poweron sequencing

The PCIe WWAN module used on brya0 requires control over 4 signals to
successfully power it on. It is desirable to do this before passing
control to the payload, because the modem requires a ~10 seconds
initialization phase before it can be used.

The corrected sequence looks like:
1) Drive device into full reset and enable power in bootblock
2) Deassert FCPO in romstage, after power rails stabilize
3) Deassert WLAN_RST#, then WLAN_PERST# in ramstage

BUG=b:187691798

Change-Id: I10f15a4dcfd86216c334fb24b4693ea250d35ee4
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57540
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: EricR Lai <ericr_lai@compal.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions