[coreboot-gerrit] Change in coreboot[master]: superio/common: Validate devicetree

[Patrick Rudolph (Code Review)]

Patrick Rudolph has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/38863 )

Change subject: superio/common: Validate devicetree
......................................................................

superio/common: Validate devicetree

As the SSDT generator for LDNs expects a "parent" PNP device
for proper ACPI code generation, validate that it is present.

Make sure the devicetree looks as expected and print a BUG message
if that's not the case.

Tested on HP Z220:
No BUG message was printed.

Change-Id: I6cbcba8ac86a2a837e23055fdd7e529f9b3277a2
Signed-off-by: Patrick Rudolph 
---
M src/superio/common/ssdt.c
1 file changed, 15 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/63/38863/1

diff --git a/src/superio/common/ssdt.c b/src/superio/common/ssdt.c
index 7aa24ea..945d0a6 100644
--- a/src/superio/common/ssdt.c
+++ b/src/superio/common/ssdt.c
@@ -168,6 +168,21 @@
    const u8 vldn = (dev->path.pnp.device >> 8) & 0x7;
    const char *hid;

+	/* Validate devicetree settings */
+	if (dev && dev->bus && dev->bus->dev) {
+		bool bug = false;
+		if (dev->bus->dev->path.type != DEVICE_PATH_PNP) {
+			bug = true;
+			printk(BIOS_CRIT, "BUG: Parent of device %s is not a PNP device\n",
+				dev_path(dev));
+		} else if (dev->bus->dev->path.pnp.port != dev->path.pnp.port) {
+			bug = true;
+			printk(BIOS_CRIT, "BUG: Parent of device %s has wrong I/O port\n",
+				dev_path(dev));
+		}
+		if (bug)
+			printk(BIOS_CRIT, "BUG: Check your devicetree!\n");
+	}
    if (!scope || !name) {
    	printk(BIOS_ERR, "%s: Missing ACPI path/scope\n", dev_path(dev));
    	return;