The current early PM setup that attempts to configure dynamic clock
gating relies on PCIe functions to be enabled that may not be.
Instead of reading port 0 or 4 directly to determine the link width
use the register that refelects the soft strapping options as this
will always be available.
Also add a clear register assignment and break for port 0 in the
switch statement instead of falling through to port 4 as that could
end up setting the slot power limit based on port 4 values instead
of based on port 0.
register 0xE1=0x3f and all other root ports should have 0xE1=0x03.
When port 0 and 4 are disabled they will have 0xE1=0x3C before
being disabled by the pch enable handler.
LUMPY default:
00:1c.0 PCI bridge: Intel Corporation Device 1c10 (rev b5)
00:1c.3 PCI bridge: Intel Corporation Device 1c16 (rev b5)
pci_read8 0 0x1c 0 0xe1
0x3f
pci_read8 0 0x1c 3 0xe1
0x03
LUMPY with PCIe port coalesce enabled:
00:1c.0 PCI bridge: Intel Corporation Device 1c10 (rev b5)
00:1c.1 PCI bridge: Intel Corporation Device 1c16 (rev b5)
pci_read8 0 0x1c 0 0xe1
0x3f
pci_read8 0 0x1c 1 0xe1
0x03
Change-Id: I33a37b0ec0c8e570cf5d9dda2c06e0225fee135c
Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/980
Tested-by: build bot (Jenkins)