Don't perform the acpi_DeviceIsPresent() check for PCI-PCI bridges. If

we are probing a PCI-PCI bridge it is because we found one by enumerating
the devices on a PCI bus, so the bridge is definitely present.  A few
BIOSes report incorrect status (_STA) for some bridges that claimed they
were not present when in fact they were.

While here, move this check earlier for Host-PCI bridges so attach fails
before doing any work that needs to be torn down.

PR:		kern/91594
Tested by:	Jack Vogel @ Intel
MFC after:	1 week

2 files changed, 7 insertions, 10 deletions

diff --git a/sys/dev/acpica/acpi_pcib.c b/sys/dev/acpica/acpi_pcib.c
index 1a42d74..c4bded8 100644
--- a/sys/dev/acpica/acpi_pcib.c
+++ b/sys/dev/acpica/acpi_pcib.c
@@ -135,15 +135,6 @@ acpi_pcib_attach(device_t dev, ACPI_BUFFER *prt, int busno)
     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
 
     /*
-     * Don't attach if we're not really there.
-     *
-     * XXX: This isn't entirely correct since we may be a PCI bus
-     * on a hot-plug docking station, etc.
-     */
-    if (!acpi_DeviceIsPresent(dev))
-	return_VALUE(ENXIO);
-
-    /*
      * Get the PCI interrupt routing table for this bus.  If we can't
      * get it, this is not an error but may reduce functionality.  There
      * are several valid bridges in the field that do not have a _PRT, so
diff --git a/sys/dev/acpica/acpi_pcib_acpi.c b/sys/dev/acpica/acpi_pcib_acpi.c
index 36d9580..882834d 100644
--- a/sys/dev/acpica/acpi_pcib_acpi.c
+++ b/sys/dev/acpica/acpi_pcib_acpi.c
@@ -287,6 +287,12 @@ acpi_pcib_acpi_attach(device_t dev)
     sc->ap_handle = acpi_get_handle(dev);
 
     /*
+     * Don't attach if we're not really there.
+     */
+    if (!acpi_DeviceIsPresent(dev))
+	return (ENXIO);
+
+    /*
      * Get our segment number by evaluating _SEG.
      * It's OK for this to not exist.
      */
@@ -353,7 +359,7 @@ acpi_pcib_acpi_attach(device_t dev)
 	if (status != AE_NOT_FOUND) {
 	    device_printf(dev, "could not evaluate _BBN - %s\n",
 		AcpiFormatException(status));
-	    return_VALUE (ENXIO);
+	    return (ENXIO);
 	} else {
 	    /* If it's not found, assume 0. */
 	    sc->ap_bus = 0;