sb/intel/lynxpoint/pcie.c: Ensure OBFF is disabled
Setting registers 64h[19:18] = 2 and 68h[14:13] = 3 enables OBFF, and
setting registers 64h[19:18] = 0 and 68h[14:13] = 0 disables OBFF.
Register at offset 0x64 is DCAP2, and offset 0x68 is DCTL2.
However, current code doesn't account for this. The result is that
register 64h[19:18] = 2 and 68h[14:13] = 0, which means the hardware is
OBFF-capable but support is disabled, which makes no sense. Given that
reference code and Broadwell both disable OBFF, disable it here too.
Change-Id: I6c1cafdb435ee22909b077128b3ae5bde5543039
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47240
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/southbridge/intel/lynxpoint/pcie.c b/src/southbridge/intel/lynxpoint/pcie.c
index 4a245b1..19eb9fa 100644
--- a/src/southbridge/intel/lynxpoint/pcie.c
+++ b/src/southbridge/intel/lynxpoint/pcie.c
@@ -645,9 +645,9 @@
pci_and_config32(dev, 0x338, ~(1 << 26));
}
- /* Enable LTR in Root Port. */
- pci_or_config32(dev, 0x64, 1 << 11);
- pci_update_config32(dev, 0x68, ~(1 << 10), (1 << 10));
+ /* Enable LTR in Root Port. Disable OBFF. */
+ pci_update_config32(dev, 0x64, ~(3 << 18), 1 << 11);
+ pci_update_config16(dev, 0x68, ~(3 << 13), 1 << 10);
pci_update_config32(dev, 0x318, ~(0xffff << 16), (0x1414 << 16));