[coreboot-gerrit] Change in coreboot[master]: soc/intel/skylake: Fix ACPI exception AE_NOT_FOUND

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/35621 )

Change subject: soc/intel/skylake: Fix ACPI exception AE_NOT_FOUND
......................................................................

soc/intel/skylake: Fix ACPI exception AE_NOT_FOUND

Make sure to match devices on the root bus only. This fixes an issue
where the SoC returned "MCHC" as ACPI name for devices behind bridge
devices, as the DEVFN matched.

Fixes observed "ACPI exception: AE_NOT_FOUND" in dmesg, as the ACPI
path no longer contains invalid names.

Tested on Supermicro X11SSH-TF.

Change-Id: I6eca37a1792287502a46a90144f2f0d8e12ae5d4
Signed-off-by: Patrick Rudolph 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35621
Tested-by: build bot (Jenkins) 
Reviewed-by: Paul Menzel 
Reviewed-by: Aaron Durbin 
---
M src/soc/intel/skylake/acpi.c
1 file changed, 4 insertions(+), 0 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Paul Menzel: Looks good to me, but someone else must approve
  Aaron Durbin: Looks good to me, approved

diff --git a/src/soc/intel/skylake/acpi.c b/src/soc/intel/skylake/acpi.c
index c3757b0..d67b502 100644
--- a/src/soc/intel/skylake/acpi.c
+++ b/src/soc/intel/skylake/acpi.c
@@ -760,6 +760,10 @@
    if (dev->path.type != DEVICE_PATH_PCI)
    	return NULL;

+	/* Only match devices on the root bus */
+	if (dev->bus && dev->bus->secondary > 0)
+		return NULL;
+
    switch (dev->path.pci.devfn) {
    case SA_DEVFN_ROOT:	return "MCHC";
    case SA_DEVFN_IGD:	return "GFX0";