From bd2a702571485d395f8d058a63e7a32f60996faa Mon Sep 17 00:00:00 2001
From: kettenis <kettenis@openbsd.org>
Date: Tue, 3 Aug 2010 22:54:12 +0000
Subject: [PATCH] Remove old code that figures out the PCI bus number.  The new
 code gets some corner cases right that the old code messed up.  As a bonus,
 this noticibly speeds up booting my Dell XPS M1330.

ok deraadt@, marco@, jordan@
---
 sys/dev/acpi/acpiprt.c | 92 +++---------------------------------------
 1 file changed, 5 insertions(+), 87 deletions(-)

diff --git a/sys/dev/acpi/acpiprt.c b/sys/dev/acpi/acpiprt.c
index cf3258e9b48..997684ccf2c 100644
--- a/sys/dev/acpi/acpiprt.c
+++ b/sys/dev/acpi/acpiprt.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: acpiprt.c,v 1.42 2010/07/21 19:35:15 deraadt Exp $ */
+/* $OpenBSD: acpiprt.c,v 1.43 2010/08/03 22:54:12 kettenis Exp $ */
 /*
  * Copyright (c) 2006 Mark Kettenis <kettenis@openbsd.org>
  *
@@ -56,7 +56,6 @@ SIMPLEQ_HEAD(, acpiprt_map) acpiprt_map_list =
 int	acpiprt_match(struct device *, void *, void *);
 void	acpiprt_attach(struct device *, struct device *, void *);
 int	acpiprt_getirq(union acpi_resource *crs, void *arg);
-int	acpiprt_getminbus(union acpi_resource *, void *);
 int	acpiprt_chooseirq(union acpi_resource *, void *);
 
 struct acpiprt_softc {
@@ -101,22 +100,13 @@ acpiprt_attach(struct device *parent, struct device *self, void *aux)
 	struct acpiprt_softc *sc = (struct acpiprt_softc *)self;
 	struct acpi_attach_args *aa = aux;
 	struct aml_value res;
-	int i, nbus;
+	int i;
 
 	sc->sc_acpi = (struct acpi_softc *)parent;
 	sc->sc_devnode = aa->aaa_node;
 	sc->sc_bus = acpiprt_getpcibus(sc, sc->sc_devnode);
-	nbus = (sc->sc_devnode->parent && sc->sc_devnode->parent->pci) ?
-		sc->sc_devnode->parent->pci->sub : -1;
 	printf(": bus %d (%s)", sc->sc_bus, sc->sc_devnode->parent->name);
 
-	if (nbus != sc->sc_bus) {
-		printf("%s: bus mismatch, new:%d old:%d\n",
-			aml_nodename(sc->sc_devnode),
-			nbus, sc->sc_bus);
-		sc->sc_bus = nbus;
-	}
-
 	if (aml_evalnode(sc->sc_acpi, sc->sc_devnode, 0, NULL, &res)) {
 		printf(": no PCI interrupt routing table\n");
 		return;
@@ -367,84 +357,12 @@ acpiprt_prt_add(struct acpiprt_softc *sc, struct aml_value *v)
 	}
 }
 
-int
-acpiprt_getminbus(union acpi_resource *crs, void *arg)
-{
-	int *bbn = arg;
-	int typ = AML_CRSTYPE(crs);
-
-	/* Check for embedded bus number */
-	if (typ == LR_WORD && crs->lr_word.type == 2)
-		*bbn = crs->lr_word._min;
-	return 0;
-}
-
 int
 acpiprt_getpcibus(struct acpiprt_softc *sc, struct aml_node *node)
 {
-	struct aml_node *parent = node->parent;
-	struct aml_value res;
-	pci_chipset_tag_t pc = NULL;
-	pcitag_t tag;
-	pcireg_t reg;
-	int bus, dev, func, rv;
-	int64_t ires;
-
-	if (parent == NULL)
-		return 0;
-
-	/*
-	 * If our parent is a a bridge, it might have an address descriptor
-	 * that tells us our bus number.
-	 */
-	if (aml_evalname(sc->sc_acpi, parent, "_CRS.", 0, NULL, &res) == 0) {
-		rv = -1;
-		aml_parse_resource(&res, acpiprt_getminbus, &rv);
-		aml_freevalue(&res);
-		if (rv != -1)
-			return rv;
-	}
-
-	/*
-	 * If our parent is the root of the bus, it should specify the
-	 * base bus number.
-	 */
-	if (aml_evalinteger(sc->sc_acpi, parent, "_BBN.", 0, NULL, &ires) == 0) {
-		return (ires);
-	}
-
-	/*
-	 * If our parent is a PCI-PCI bridge, get our bus number from its
-	 * PCI config space.
-	 */
-	if (aml_evalinteger(sc->sc_acpi, parent, "_ADR.", 0, NULL, &ires) == 0) {
-		bus = acpiprt_getpcibus(sc, parent);
-		dev = ACPI_PCI_DEV(ires << 16);
-		func = ACPI_PCI_FN(ires << 16);
-
-		/*
-		 * Some systems return 255 as the device number for
-		 * devices that are not really there.
-		 */
-		if (dev >= pci_bus_maxdevs(pc, bus))
-			return (-1);
-
-		tag = pci_make_tag(pc, bus, dev, func);
-
-		/* Check whether the device is really there. */
-		reg = pci_conf_read(pc, tag, PCI_ID_REG);
-		if (PCI_VENDOR(reg) == PCI_VENDOR_INVALID)
-			return (-1);
-
-		/* Fetch bus number from PCI config space. */
-		reg = pci_conf_read(pc, tag, PCI_CLASS_REG);
-		if (PCI_CLASS(reg) == PCI_CLASS_BRIDGE &&
-		    PCI_SUBCLASS(reg) == PCI_SUBCLASS_BRIDGE_PCI) {
-			reg = pci_conf_read(pc, tag, PPB_REG_BUSINFO);
-			return (PPB_BUSINFO_SECONDARY(reg));
-		}
-	}
-	return (0);
+	/* Check if parent device has PCI mapping */
+	return (node->parent && node->parent->pci) ?
+		node->parent->pci->sub : -1;
 }
 
 void
-- 
2.20.1