From: Steven Smith <ssmith@weybridge.uk.xensource.com>
Date: Tue, 30 Jun 2009 11:55:48 +0000 (+0100)
Subject: patch pci-ignore
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=f113ad75fe1dad24ee2c29e29b0e88c7218f9dc9;p=people%2Fssmith%2Fnc2-2.6.27.git

patch pci-ignore
---

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 1964c670..cf0a00cb 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -23,6 +23,9 @@
 
 unsigned int pci_pm_d3_delay = 10;
 
+struct pci_ignore pci_ignore_list[512] __devinitdata = {{-1,-1,-1},};
+int pci_ignore_count __devinitdata = 0;
+
 #ifdef CONFIG_PCI_DOMAINS
 int pci_domains_supported = 1;
 #endif
@@ -1927,6 +1930,33 @@ static int __devinit pci_init(void)
 	return 0;
 }
 
+static int __devinit pci_ignore(char *str)
+{
+	unsigned int bus = -1u, dev = -1u, fn = -1u;
+	int fields;
+
+	fields = sscanf(str, "ignore-%x-%x-%x", &bus, &dev, &fn);
+	if (fields < 1 || fields > 3) 
+		return 0;
+
+	if (pci_ignore_count >= 512) 
+		return 0;
+
+	printk(KERN_INFO "PCI: Ignoring %2.2x", bus);
+	if (dev != -1u)
+		printk(".%2.2x", dev);
+	if (fn != -1u)
+		printk(".%2.2x", dev);
+	printk("\n");
+
+	pci_ignore_list[pci_ignore_count].bus = bus;
+	pci_ignore_list[pci_ignore_count].dev = dev;
+	pci_ignore_list[pci_ignore_count].fn = fn;
+	pci_ignore_count++;
+
+	return 1;
+}
+
 static int __devinit pci_setup(char *str)
 {
 	while (str) {
@@ -1944,7 +1974,7 @@ static int __devinit pci_setup(char *str)
 				pci_cardbus_io_size = memparse(str + 9, &str);
 			} else if (!strncmp(str, "cbmemsize=", 10)) {
 				pci_cardbus_mem_size = memparse(str + 10, &str);
-			} else {
+			} else if (!pci_ignore(str)) {
 				printk(KERN_ERR "PCI: Unknown option `%s'\n",
 						str);
 			}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 9b7f9cc3..b7a59d7a 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -131,6 +131,31 @@ pci_match_one_device(const struct pci_device_id *id, const struct pci_dev *dev)
 	return NULL;
 }
 
+/* Linked list of pci bus/dev/fn combinations not to touch */
+struct pci_ignore {
+	unsigned int bus, dev, fn; /* what to ignore; -1u means wildcard */
+};
+
+extern struct pci_ignore pci_ignore_list[];
+extern int pci_ignore_count;
+
+static inline int __devinit pci_ignore_chk(unsigned int bus, 
+					   unsigned int dev, 
+					   unsigned int fn)
+{
+	int i;
+	struct pci_ignore *ig = pci_ignore_list;
+	for (i = 0; i < pci_ignore_count; i++)
+		if (ig[i].bus == bus 
+		    && (ig[i].dev == dev || ig[i].dev == -1u)
+		    && (ig[i].fn == fn || ig[i].fn == -1u))
+			return 1;
+	return 0;
+}
+
+#define pci_ignore_bus(_b)     pci_ignore_chk((_b), -1u, -1u)
+#define pci_ignore_dev(_b, _d) pci_ignore_chk((_b), (_d), -1u)
+#define pci_ignore_fn(_b, _f)  pci_ignore_chk((_b), PCI_SLOT(_f), PCI_FUNC(_f))
 struct pci_dev *pci_find_upstream_pcie_bridge(struct pci_dev *pdev);
 
 /* PCI slot sysfs helper code */
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index eb6c8d15..f12de80e 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -955,6 +955,13 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
 	u8 hdr_type;
 	int delay = 1;
 
+	if (pci_ignore_fn(bus->number, devfn)) {
+		pr_debug("PCI: skipping dev/fn %04x:%02x:%02x:%02x\n",
+			 pci_domain_nr(bus), bus->number,
+			 PCI_SLOT(devfn), PCI_SLOT(devfn));
+		return NULL;
+	}
+
 	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
 		return NULL;
 
@@ -1071,6 +1078,12 @@ int pci_scan_slot(struct pci_bus *bus, int devfn)
 	int func, nr = 0;
 	int scan_all_fns;
 
+	if (pci_ignore_dev(bus->number, PCI_SLOT(devfn))) {
+		pr_debug("PCI: skipping dev %04x:%02x:%02x\n",
+			 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn));
+		return nr;
+	}
+
 	scan_all_fns = pcibios_scan_all_fns(bus, devfn);
 
 	for (func = 0; func < 8; func++, devfn++) {
@@ -1109,6 +1122,12 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
 	unsigned int devfn, pass, max = bus->secondary;
 	struct pci_dev *dev;
 
+	if (pci_ignore_bus(bus->number)) {
+		pr_debug("PCI: skipping bus %04x:%02x\n",
+			 pci_domain_nr(bus), bus->number);
+		return max;
+	}
+
 	pr_debug("PCI: Scanning bus %04x:%02x\n", pci_domain_nr(bus), bus->number);
 
 	/* Go find them, Rover! */