mb/google/brya/var/agah: Fix GPU power sequencing

While testing the power sequencing code for the GPU, a few mistakes were
found. This patch fixes those errors:

1) FBVDD load-switch enable is active-low
2) NVVDD VR enable is active-high
3) GPU_PERST_L should be driven low during GPIO table programming
4) The BAR saving code missed the top 32 bits of 64-bit BARs
5) sequence_rail() assumed the pwr_en_gpio and pg_gpio were the same
   polarity
6) PEG vGPIOs were not programmed to the correct NF

BUG=b:233552225
TEST=dGPU is able to successfully enumerate over PCIe bus

Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I85767d382012a0c7dfdb1f849768e0160f06c273
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64727
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions