Nvidia recommends saving and restoring the LTR Enable bit in PCIe config
space for the PCIe root port before/after GC6 entry. Also the detectable
error bit should be cleared, as there may be errors expected during the
GC6 flow.
BUG=b:214581763
TEST=no more correctable errors after GC6 entry/exit
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I058ce1b3f17fb6cc59785a85efaf9ea0504cf2ee
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66808
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Anil Kumar K <anil.kumar.k@intel.corp-partner.google.com>
Reviewed-by: Ivy Jian <ivy.jian@quanta.corp-partner.google.com>