eric patch
        1. x86_setup_mtrr take address bit.
        2. generic ht, pcix, pcie beidge...
        3. scan bus and reset_bus
        4. ht read ctrl to decide if the ht chain
           is ready
        5. Intel e7520 and e7525 support
        6. new ich5r support
        7. intel sb 6300 support.

yhlu patch
	1. split x86_setup_mtrrs to fixed and var
	2. if (resource->flags & IORESOURCE_FIXED ) return; in device.c pick_largest_resource
	3. in_conherent.c K8_SCAN_PCI_BUS


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1982 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/devices/pci_device.c b/src/devices/pci_device.c
index 3f9a1ca..f3f53f0 100644
--- a/src/devices/pci_device.c
+++ b/src/devices/pci_device.c
@@ -21,8 +21,23 @@
 #include <part/hard_reset.h>
 #include <part/fallback_boot.h>
 #include <delay.h>
+#if CONFIG_HYPERTRANSPORT_PLUGIN_SUPPORT == 1
+#include <device/hypertransport.h>
+#endif
+#if CONFIG_PCIX_PLUGIN_SUPPORT == 1
+#include <device/pcix.h>
+#endif
+#if CONFIG_PCIEXP_PLUGIN_SUPPORT == 1
+#include <device/pciexp.h>
+#endif
+#if CONFGI_AGP_PLUGIN_SUPPORT == 1
+#include <device/agp.h>
+#endif
+#if CONFIG_CARDBUS_PLUGIN_SUPPORT == 1
+#include <device/cardbus.h>
+#endif
 
-static uint8_t pci_moving_config8(struct device *dev, unsigned reg)
+uint8_t pci_moving_config8(struct device *dev, unsigned reg)
 {
 	uint8_t value, ones, zeroes;
 	value = pci_read_config8(dev, reg);
@@ -38,7 +53,7 @@
 	return ones ^ zeroes;
 }
 
-static uint16_t pci_moving_config16(struct device *dev, unsigned reg)
+uint16_t pci_moving_config16(struct device *dev, unsigned reg)
 {
 	uint16_t value, ones, zeroes;
 	value = pci_read_config16(dev, reg);
@@ -54,7 +69,7 @@
 	return ones ^ zeroes;
 }
 
-static uint32_t pci_moving_config32(struct device *dev, unsigned reg)
+uint32_t pci_moving_config32(struct device *dev, unsigned reg)
 {
 	uint32_t value, ones, zeroes;
 	value = pci_read_config32(dev, reg);
@@ -70,29 +85,53 @@
 	return ones ^ zeroes;
 }
 
-unsigned pci_find_capability(device_t dev, unsigned cap)
+unsigned pci_find_next_capability(device_t dev, unsigned cap, unsigned last)
 {
 	unsigned pos;
+	unsigned status;
+	unsigned reps = 48;
 	pos = 0;
+	status = pci_read_config16(dev, PCI_STATUS);
+	if (!(status & PCI_STATUS_CAP_LIST)) {
+		return 0;
+	}
 	switch(dev->hdr_type & 0x7f) {
 	case PCI_HEADER_TYPE_NORMAL:
 	case PCI_HEADER_TYPE_BRIDGE:
 		pos = PCI_CAPABILITY_LIST;
 		break;
+	case PCI_HEADER_TYPE_CARDBUS:
+		pos = PCI_CB_CAPABILITY_LIST;
+		break;
+	default:
+		return 0;
 	}
-	if (pos > PCI_CAP_LIST_NEXT) {
-		pos = pci_read_config8(dev, pos);
-	}
-	while (pos != 0) {   /* loop through the linked list */
+	pos = pci_read_config8(dev, pos);
+	while(reps-- && (pos >= 0x40)) {   /* loop through the linked list */
 		int this_cap;
+		pos &= ~3;
 		this_cap = pci_read_config8(dev, pos + PCI_CAP_LIST_ID);
-		if (this_cap == cap) {
+		printk_spew("Capability: 0x%02x @ 0x%02x\n", cap, pos);
+		if (this_cap == 0xff) {
+			break;
+		}
+		if (!last && (this_cap == cap)) {
 			return pos;
 		}
+		if (last == pos) {
+			last = 0;
+		}
+		pos = pci_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
 	}
 	return 0;
 }
 
+unsigned pci_find_capability(device_t dev, unsigned cap)
+{
+	return pci_find_next_capability(dev, cap, 0);
+
+}
+
 /** Given a device and register, read the size of the BAR for that register. 
  * @param dev       Pointer to the device structure
  * @param resource  Pointer to the resource structure
@@ -118,7 +157,7 @@
 
 	/* If it is a 64bit resource look at the high half as well */
 	if (((attr & PCI_BASE_ADDRESS_SPACE_IO) == 0) &&
-	    ((attr & PCI_BASE_ADDRESS_MEM_LIMIT_MASK) == PCI_BASE_ADDRESS_MEM_LIMIT_64))
+		((attr & PCI_BASE_ADDRESS_MEM_LIMIT_MASK) == PCI_BASE_ADDRESS_MEM_LIMIT_64))
 	{
 		/* Find the high bits that move */
 		moving |= ((resource_t)pci_moving_config32(dev, index + 4)) << 32;
@@ -134,7 +173,7 @@
 	if (moving) {
 		resource->size = 1;
 		resource->align = resource->gran = 0;
-		while (!(moving & resource->size)) {
+		while(!(moving & resource->size)) {
 			resource->size <<= 1;
 			resource->align += 1;
 			resource->gran  += 1;
@@ -154,17 +193,20 @@
 	 */
 	if (moving == 0) {
 		if (value != 0) {
-			printk_debug("%s register %02x(%08x), read-only ignoring it\n",
-				     dev_path(dev), index, value);
+			printk_debug(
+				"%s register %02x(%08x), read-only ignoring it\n",
+				dev_path(dev), index, value);
 		}
 		resource->flags = 0;
-	} else if (attr & PCI_BASE_ADDRESS_SPACE_IO) {
+	}
+	else if (attr & PCI_BASE_ADDRESS_SPACE_IO) {
 		/* An I/O mapped base address */
 		attr &= PCI_BASE_ADDRESS_IO_ATTR_MASK;
 		resource->flags |= IORESOURCE_IO;
 		/* I don't want to deal with 32bit I/O resources */
 		resource->limit = 0xffff;
-	} else {
+	} 
+	else {
 		/* A Memory mapped base address */
 		attr &= PCI_BASE_ADDRESS_MEM_ATTR_MASK;
 		resource->flags |= IORESOURCE_MEM;
@@ -175,14 +217,17 @@
 		if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_32) {
 			/* 32bit limit */
 			resource->limit = 0xffffffffUL;
-		} else if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_1M) {
+		}
+		else if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_1M) {
 			/* 1MB limit */
 			resource->limit = 0x000fffffUL;
-		} else if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_64) {
+		}
+		else if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_64) {
 			/* 64bit limit */
 			resource->limit = 0xffffffffffffffffULL;
 			resource->flags |= IORESOURCE_PCI64;
-		} else {
+		}
+		else {
 			/* Invalid value */
 			resource->flags = 0;
 		}
@@ -194,18 +239,15 @@
 #if 0
 	if (resource->flags) {
 		printk_debug("%s %02x ->",
-			     dev_path(dev), resource->index);
+			dev_path(dev), resource->index);
 		printk_debug(" value: 0x%08Lx zeroes: 0x%08Lx ones: 0x%08Lx attr: %08lx\n",
-			     value, zeroes, ones, attr);
+			value, zeroes, ones, attr);
 		printk_debug(
-			"%s %02x -> size: 0x%08Lx max: 0x%08Lx %s%s\n ",
+			"%s %02x -> size: 0x%08Lx max: 0x%08Lx %s\n ",
 			dev_path(dev),
 			resource->index,
 			resource->size,	resource->limit,
-			(resource->flags == 0) ? "unused":
-			(resource->flags & IORESOURCE_IO)? "io":
-			(resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem",
-			(resource->flags & IORESOURCE_PCI64)?"64":"");
+			resource_type(resource));
 	}
 #endif
 
@@ -272,32 +314,32 @@
 		resource->flags |= IORESOURCE_MEM | IORESOURCE_READONLY |
 			IORESOURCE_ASSIGNED | IORESOURCE_FIXED;
 	}  
+
+	compact_resources(dev);
 }
 
 /** Read the base address registers for a given device. 
  * @param dev Pointer to the dev structure
  * @param howmany How many registers to read (6 for device, 2 for bridge)
  */
-static void pci_read_bases(struct device *dev, unsigned int howmany, unsigned long rom)
+static void pci_read_bases(struct device *dev, unsigned int howmany)
 {
 	unsigned long index;
 
-	for (index = PCI_BASE_ADDRESS_0; (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) {
+	for(index = PCI_BASE_ADDRESS_0; (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) {
 		struct resource *resource;
 		resource = pci_get_resource(dev, index);
 		index += (resource->flags & IORESOURCE_PCI64)?8:4;
 	}
-	if (rom)
-		pci_get_rom_resource(dev, rom);
 
 	compact_resources(dev);
 }
 
 static void pci_set_resource(struct device *dev, struct resource *resource);
 
-static void pci_record_bridge_resource( struct device *dev, resource_t moving,
-					unsigned index, unsigned long mask,
-					unsigned long type)
+static void pci_record_bridge_resource(
+	struct device *dev, resource_t moving,
+	unsigned index, unsigned long mask, unsigned long type)
 {
 	/* Initiliaze the constraints on the current bus */
 	struct resource *resource;
@@ -346,8 +388,10 @@
 	moving = moving_base & moving_limit;
 
 	/* Initialize the io space constraints on the current bus */
-	pci_record_bridge_resource(dev, moving, PCI_IO_BASE,
-				   IORESOURCE_IO, IORESOURCE_IO);
+	pci_record_bridge_resource(
+		dev, moving, PCI_IO_BASE, 
+		IORESOURCE_IO, IORESOURCE_IO);
+
 
 	/* See if the bridge prefmem resources are implemented */
 	moving_base =  ((resource_t)pci_moving_config16(dev, PCI_PREF_MEMORY_BASE)) << 16;
@@ -358,9 +402,11 @@
 	
 	moving = moving_base & moving_limit;
 	/* Initiliaze the prefetchable memory constraints on the current bus */
-	pci_record_bridge_resource(dev, moving, PCI_PREF_MEMORY_BASE, 
-				   IORESOURCE_MEM | IORESOURCE_PREFETCH,
-				   IORESOURCE_MEM | IORESOURCE_PREFETCH);
+	pci_record_bridge_resource(
+		dev, moving, PCI_PREF_MEMORY_BASE, 
+		IORESOURCE_MEM | IORESOURCE_PREFETCH,
+		IORESOURCE_MEM | IORESOURCE_PREFETCH);
+	
 
 	/* See if the bridge mem resources are implemented */
 	moving_base = ((uint32_t)pci_moving_config16(dev, PCI_MEMORY_BASE)) << 16;
@@ -369,26 +415,25 @@
 	moving = moving_base & moving_limit;
 
 	/* Initialize the memory resources on the current bus */
-	pci_record_bridge_resource(dev, moving, PCI_MEMORY_BASE, 
-				   IORESOURCE_MEM | IORESOURCE_PREFETCH,
-				   IORESOURCE_MEM);
+	pci_record_bridge_resource(
+		dev, moving, PCI_MEMORY_BASE, 
+		IORESOURCE_MEM | IORESOURCE_PREFETCH,
+		IORESOURCE_MEM);
 
 	compact_resources(dev);
 }
 
 void pci_dev_read_resources(struct device *dev)
 {
-	uint32_t addr;
-
-	pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
+	pci_read_bases(dev, 6);
+	pci_get_rom_resource(dev, PCI_ROM_ADDRESS);
 }
 
 void pci_bus_read_resources(struct device *dev)
 {
-	uint32_t addr;
-
 	pci_bridge_read_bases(dev);
-	pci_read_bases(dev, 2,  PCI_ROM_ADDRESS1);
+	pci_read_bases(dev, 2);
+	pci_get_rom_resource(dev, PCI_ROM_ADDRESS1);
 }
 
 static void pci_set_resource(struct device *dev, struct resource *resource)
@@ -397,8 +442,10 @@
 
 	/* Make certain the resource has actually been set */
 	if (!(resource->flags & IORESOURCE_ASSIGNED)) {
-		printk_err("ERROR: %s %02x not allocated\n",
-			dev_path(dev), resource->index);
+		printk_err("ERROR: %s %02x %s size: 0x%010Lx not assigned\n",
+			dev_path(dev), resource->index,
+			resource_type(resource),
+			resource->size);
 		return;
 	}
 
@@ -497,10 +544,10 @@
 
 	last = &dev->resource[dev->resources];
 
-	for (resource = &dev->resource[0]; resource < last; resource++) {
+	for(resource = &dev->resource[0]; resource < last; resource++) {
 		pci_set_resource(dev, resource);
 	}
-	for (link = 0; link < dev->links; link++) {
+	for(link = 0; link < dev->links; link++) {
 		struct bus *bus;
 		bus = &dev->link[link];
 		if (bus->children) {
@@ -551,14 +598,10 @@
 void pci_bus_enable_resources(struct device *dev)
 {
 	uint16_t ctrl;
-
-#if CONFIG_CONSOLE_VGA == 1
 	/* enable IO in command register if there is VGA card
 	 * connected with (even it does not claim IO resource) */
 	if (dev->link[0].bridge_ctrl & PCI_BRIDGE_CTL_VGA)
 		dev->command |= PCI_COMMAND_IO;
-#endif
-
 	ctrl = pci_read_config16(dev, PCI_BRIDGE_CONTROL);
 	ctrl |= dev->link[0].bridge_ctrl;
 	ctrl |= (PCI_BRIDGE_CTL_PARITY + PCI_BRIDGE_CTL_SERR); /* error check */
@@ -570,15 +613,27 @@
 	enable_childrens_resources(dev);
 }
 
+void pci_bus_reset(struct bus *bus)
+{
+	unsigned ctl;
+	ctl = pci_read_config16(bus->dev, PCI_BRIDGE_CONTROL);
+	ctl |= PCI_BRIDGE_CTL_BUS_RESET;
+	pci_write_config16(bus->dev, PCI_BRIDGE_CONTROL, ctl);
+	mdelay(10);
+	ctl &= ~PCI_BRIDGE_CTL_BUS_RESET;
+	pci_write_config16(bus->dev, PCI_BRIDGE_CONTROL, ctl);
+	delay(1);
+}
+
 void pci_dev_set_subsystem(device_t dev, unsigned vendor, unsigned device)
 {
 	pci_write_config32(dev, PCI_SUBSYSTEM_VENDOR_ID, 
 		((device & 0xffff) << 16) | (vendor & 0xffff));
 }
 
-#if CONFIG_PCI_ROM_RUN == 1
 void pci_dev_init(struct device *dev)
 {
+#if CONFIG_PCI_ROM_RUN == 1
 	struct rom_header *rom, *ram;
 
 	rom = pci_rom_probe(dev);
@@ -589,8 +644,8 @@
 		return;
 
 	run_bios(dev, ram);
-}
 #endif
+}
 
 /** Default device operation for PCI devices */
 static struct pci_operations pci_dev_ops_pci = {
@@ -601,11 +656,7 @@
 	.read_resources   = pci_dev_read_resources,
 	.set_resources    = pci_dev_set_resources,
 	.enable_resources = pci_dev_enable_resources,
-#if CONFIG_PCI_ROM_RUN == 1
 	.init		  = pci_dev_init,
-#else
-	.init		  = 0,
-#endif
 	.scan_bus	  = 0,
 	.enable           = 0,
 	.ops_pci          = &pci_dev_ops_pci,
@@ -623,10 +674,79 @@
 	.init		  = 0,
 	.scan_bus	  = pci_scan_bridge,
 	.enable           = 0,
+	.reset_bus        = pci_bus_reset,
 	.ops_pci          = &pci_bus_ops_pci,
 };
 
 /**
+ * @brief Detect the type of downstream bridge
+ *
+ * This function is a heuristic to detect which type
+ * of bus is downstream of a pci to pci bridge.  This
+ * functions by looking for various capability blocks
+ * to figure out the type of downstream bridge.  PCI-X
+ * PCI-E, and Hypertransport all seem to have appropriate
+ * capabilities.
+ * 
+ * When only a PCI-Express capability is found the type
+ * is examined to see which type of bridge we have.
+ *
+ * @param dev
+ * 
+ * @return appropriate bridge operations
+ */
+static struct device_operations *get_pci_bridge_ops(device_t dev)
+{
+	unsigned pos;
+
+#if CONFIG_PCIX_PLUGIN_SUPPORT == 1
+	pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
+	if (pos) {
+		printk_debug("%s subbordinate bus PCI-X\n", dev_path(dev));
+		return &default_pcix_ops_bus;
+	}
+#endif
+#if CONFIG_AGP_PLUGIN_SUPPORT == 1
+	/* How do I detect an PCI to AGP bridge? */
+#endif
+#if CONFIG_HYPERTRANSPORT_PLUGIN_SUPPORT == 1
+	pos = 0;
+	while((pos = pci_find_next_capability(dev, PCI_CAP_ID_HT, pos))) {
+		unsigned flags;
+		flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
+		if ((flags >> 13) == 1) {
+			/* Host or Secondary Interface */
+			printk_debug("%s subbordinate bus Hypertransport\n", 
+				dev_path(dev));
+			return &default_ht_ops_bus;
+		}
+	}
+#endif
+#if CONFIG_PCIEXP_PLUGIN_SUPPORT == 1
+	pos = pci_find_capability(dev, PCI_CAP_ID_PCIE);
+	if (pos) {
+		unsigned flags;
+		flags = pci_read_config16(dev, pos + PCI_EXP_FLAGS);
+		switch((flags & PCI_EXP_FLAGS_TYPE) >> 4) {
+		case PCI_EXP_TYPE_ROOT_PORT:
+		case PCI_EXP_TYPE_UPSTREAM:
+		case PCI_EXP_TYPE_DOWNSTREAM:
+			printk_debug("%s subbordinate bus PCI Express\n", 
+				dev_path(dev));
+			return &default_pciexp_ops_bus;
+		case PCI_EXP_TYPE_PCI_BRIDGE:
+			printk_debug("%s subbordinate PCI\n", 
+				dev_path(dev));
+			return &default_pci_ops_bus;
+		default:
+			break;
+		}
+	}
+#endif
+	return &default_pci_ops_bus;
+}
+
+/**
  * @brief Set up PCI device operation
  *
  *
@@ -644,12 +764,12 @@
 	/* Look through the list of setup drivers and find one for
 	 * this pci device 
 	 */
-	for (driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) {
+	for(driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) {
 		if ((driver->vendor == dev->vendor) &&
-		    (driver->device == dev->device)) 
+			(driver->device == dev->device)) 
 		{
 			dev->ops = driver->ops;
-			printk_debug("%s [%04x/%04x] %sops\n", 
+			printk_spew("%s [%04x/%04x] %sops\n", 
 				dev_path(dev),
 				driver->vendor, driver->device,
 				(driver->ops->scan_bus?"bus ":""));
@@ -667,8 +787,13 @@
 	case PCI_HEADER_TYPE_BRIDGE:
 		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
 			goto bad;
-		dev->ops = &default_pci_ops_bus;
+		dev->ops = get_pci_bridge_ops(dev);
 		break;
+#if CONFIG_CARDBUS_PLUGIN_SUPPORT == 1
+	case PCI_HEADER_TYPE_CARDBUS:
+		dev->ops = &default_cardbus_ops_bus;
+		break;
+#endif
 	default:
 	bad:
 		if (dev->enabled) {
@@ -682,6 +807,8 @@
 	return;
 }
 
+
+
 /**
  * @brief See if we have already allocated a device structure for a given devfn.
  *
@@ -702,7 +829,7 @@
 	for(; *list; list = &(*list)->sibling) {
 		if ((*list)->path.type != DEVICE_PATH_PCI) {
 			printk_err("child %s not a pci device\n",
-				   dev_path(*list));
+				dev_path(*list));
 			continue;
 		}
 		if ((*list)->path.u.pci.devfn == devfn) {
@@ -713,15 +840,15 @@
 			break;
 		}
 	}
-	/* Just like alloc_dev add the device to the list of device on the bus.
-	 * When the list of devices was formed we removed all of the parents
-	 * children, and now we are interleaving static and dynamic devices in
+	/* Just like alloc_dev add the device to the  list of device on the bus.  
+	 * When the list of devices was formed we removed all of the parents 
+	 * children, and now we are interleaving static and dynamic devices in 
 	 * order on the bus.
 	 */
 	if (dev) {
 		device_t child;
 		/* Find the last child of our parent */
-		for (child = dev->bus->children; child && child->sibling; ) {
+		for(child = dev->bus->children; child && child->sibling; ) {
 			child = child->sibling;
 		}
 		/* Place the device on the list of children of it's parent. */
@@ -738,9 +865,128 @@
 /** 
  * @brief Scan a PCI bus.
  *
+ * Determine the existence of a given PCI device.
+ *
+ * @param bus pointer to the bus structure
+ * @param devfn to look at
+ *
+ * @return The device structure for hte device (if found)
+ *         or the NULL if no device is found.
+ */
+device_t pci_probe_dev(device_t dev, struct bus *bus, unsigned devfn)
+{
+	uint32_t id, class;
+	uint8_t hdr_type;
+
+	/* Detect if a device is present */
+	if (!dev) {
+		struct device dummy;
+		dummy.bus              = bus;
+		dummy.path.type        = DEVICE_PATH_PCI;
+		dummy.path.u.pci.devfn = devfn;
+		id = pci_read_config32(&dummy, PCI_VENDOR_ID);
+		/* Have we found somthing?
+		 * Some broken boards return 0 if a slot is empty.
+		 */
+		if (	(id == 0xffffffff) || (id == 0x00000000) ||
+			(id == 0x0000ffff) || (id == 0xffff0000))
+		{
+			printk_spew("PCI: devfn 0x%x, bad id 0x%x\n", devfn, id);
+			return NULL;
+		}
+		dev = alloc_dev(bus, &dummy.path);
+	}
+	else {
+		/* Enable/disable the device.  Once we have
+		 * found the device specific operations this
+		 * operations we will disable the device with
+		 * those as well.
+		 * 
+		 * This is geared toward devices that have subfunctions
+		 * that do not show up by default.
+		 * 
+		 * If a device is a stuff option on the motherboard
+		 * it may be absent and enable_dev must cope.
+		 * 
+		 */
+		/* Run the magice enable sequence for the device */
+		if (dev->chip_ops && dev->chip_ops->enable_dev) {
+			dev->chip_ops->enable_dev(dev);
+		}
+		/* Now read the vendor and device id */
+		id = pci_read_config32(dev, PCI_VENDOR_ID);
+		
+		
+		/* If the device does not have a pci id disable it.
+		 * Possibly this is because we have already disabled
+		 * the device.  But this also handles optional devices
+		 * that may not always show up.
+		 */
+		/* If the chain is fully enumerated quit */
+		if (	(id == 0xffffffff) || (id == 0x00000000) ||
+			(id == 0x0000ffff) || (id == 0xffff0000)) 
+		{
+			if (dev->enabled) {
+				printk_info("Disabling static device: %s\n",
+					dev_path(dev));
+				dev->enabled = 0;
+			}
+			return dev;
+		}
+	}
+	/* Read the rest of the pci configuration information */
+	hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
+	class = pci_read_config32(dev, PCI_CLASS_REVISION);
+	
+	/* Store the interesting information in the device structure */
+	dev->vendor = id & 0xffff;
+	dev->device = (id >> 16) & 0xffff;
+	dev->hdr_type = hdr_type;
+	/* class code, the upper 3 bytes of PCI_CLASS_REVISION */
+	dev->class = class >> 8;
+	
+
+	/* Architectural/System devices always need to
+	 * be bus masters.
+	 */
+	if ((dev->class >> 16) == PCI_BASE_CLASS_SYSTEM) {
+		dev->command |= PCI_COMMAND_MASTER;
+	}
+	/* Look at the vendor and device id, or at least the 
+	 * header type and class and figure out which set of
+	 * configuration methods to use.  Unless we already
+	 * have some pci ops.
+	 */
+	set_pci_ops(dev);
+
+	/* Now run the magic enable/disable sequence for the device */
+	if (dev->ops && dev->ops->enable) {
+		dev->ops->enable(dev);
+	}
+	
+
+	/* Display the device and error if we don't have some pci operations
+	 * for it.
+	 */
+	printk_debug("%s [%04x/%04x] %s%s\n",
+		dev_path(dev),
+		dev->vendor, dev->device, 
+		dev->enabled?"enabled": "disabled",
+		dev->ops?"" : " No operations"
+		);
+
+	return dev;
+}
+
+/** 
+ * @brief Scan a PCI bus.
+ *
  * Determine the existence of devices and bridges on a PCI bus. If there are
  * bridges on the bus, recursively scan the buses behind the bridges.
  *
+ * This function is the default scan_bus() method for the root device
+ * 'dev_root'.
+ *
  * @param bus pointer to the bus structure
  * @param min_devfn minimum devfn to look at in the scan usually 0x00
  * @param max_devfn maximum devfn to look at in the scan usually 0xff
@@ -748,11 +994,11 @@
  *
  * @return The maximum bus number found, after scanning all subordinate busses
  */
-unsigned int pci_scan_bus(struct bus *bus, unsigned min_devfn, unsigned max_devfn,
-			  unsigned int max)
+unsigned int pci_scan_bus(struct bus *bus,
+	unsigned min_devfn, unsigned max_devfn,
+	unsigned int max)
 {
 	unsigned int devfn;
-	device_t dev;
 	device_t old_devices;
 	device_t child;
 
@@ -762,141 +1008,49 @@
 	bus->children = 0;
 
 	post_code(0x24);
-
 	/* probe all devices/functions on this bus with some optimization for
 	 * non-existence and single funcion devices
 	 */
 	for (devfn = min_devfn; devfn <= max_devfn; devfn++) {
-		uint32_t id, class;
-		uint8_t hdr_type;
+		device_t dev;
 
 		/* First thing setup the device structure */
 		dev = pci_scan_get_dev(&old_devices, devfn);
-	
-		/* Detect if a device is present */
-		if (!dev) {
-			struct device dummy;
-			dummy.bus              = bus;
-			dummy.path.type        = DEVICE_PATH_PCI;
-			dummy.path.u.pci.devfn = devfn;
-			id = pci_read_config32(&dummy, PCI_VENDOR_ID);
-			/* some broken boards return 0 if a slot is empty: */
-			if ((id == 0xffffffff) || (id == 0x00000000) || 
-			    (id == 0x0000ffff) || (id == 0xffff0000))
-			{
-				printk_spew("PCI: devfn 0x%x, bad id 0x%x\n", devfn, id);
-				if (PCI_FUNC(devfn) == 0x00) {
-					/* if this is a function 0 device and 
-					 * it is not present,
-					 * skip to next device 
-					 */
-					devfn += 0x07;
-				}
-				/* This function in a multi function device is
-				 * not present, skip to the next function.
-				 */
-				continue;
-			}
-			dev = alloc_dev(bus, &dummy.path);
-		}
-		else {
-			/* Enable/disable the device.  Once we have
-			 * found the device specific operations this
-			 * operations we will disable the device with
-			 * those as well.
-			 * 
-			 * This is geared toward devices that have subfunctions
-			 * that do not show up by default.
-			 * 
-			 * If a device is a stuff option on the motherboard
-			 * it may be absent and enable_dev must cope.
-			 * 
-			 */
-			if (dev->chip_ops && dev->chip_ops->enable_dev) 
-			{
-				dev->chip_ops->enable_dev(dev);
-			}
-			/* Now read the vendor and device id */
-			id = pci_read_config32(dev, PCI_VENDOR_ID);
-			
-			/* If the device does not have a pci id disable it.
-			 * Possibly this is because we have already disabled
-			 * the device.  But this also handles optional devices
-			 * that may not always show up.
-			 */
-			if (id == 0xffffffff || id == 0x00000000 ||
-			    id == 0x0000ffff || id == 0xffff0000) 
-			{
-				if (dev->enabled) {
-					printk_info("Disabling static device: %s\n",
-						dev_path(dev));
-					dev->enabled = 0;
-				}
-				continue;
-			}
-		}
-		/* Read the rest of the pci configuration information */
-		hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
-		class = pci_read_config32(dev, PCI_CLASS_REVISION);
 
-		/* Store the interesting information in the device structure */
-		dev->vendor = id & 0xffff;
-		dev->device = (id >> 16) & 0xffff;
-		dev->hdr_type = hdr_type;
-		/* class code, the upper 3 bytes of PCI_CLASS_REVISION */
-		dev->class = class >> 8;
-
-		/* Architectural/System devices always need to
-		 * be bus masters.
+		/* See if a device is present and setup the device
+		 * structure.
 		 */
-		if ((dev->class >> 16) == PCI_BASE_CLASS_SYSTEM) {
-			dev->command |= PCI_COMMAND_MASTER;
-		}
+		dev = pci_probe_dev(dev, bus, devfn); 
 
-		/* Look at the vendor and device id, or at least the 
-		 * header type and class and figure out which set of
-		 * configuration methods to use.  Unless we already
-		 * have some pci ops.
+		/* if this is not a multi function device, 
+		 * or the device is not present don't waste
+		 * time probing another function. 
+		 * Skip to next device. 
 		 */
-		set_pci_ops(dev);
-		/* Error if we don't have some pci operations for it */
-		if (!dev->ops) {
-			printk_err("%s No device operations\n",
-				dev_path(dev));
-			continue;
-		}
-
-		/* Now run the magic enable/disable sequence for the device */
-		if (dev->ops && dev->ops->enable) {
-			dev->ops->enable(dev);
-		}
-
-		printk_debug("%s [%04x/%04x] %s\n", 
-			dev_path(dev),
-			dev->vendor, dev->device, 
-			dev->enabled?"enabled": "disabled");
-
-		if (PCI_FUNC(devfn) == 0x00 && (hdr_type & 0x80) != 0x80) {
-			/* if this is not a multi function device, 
-			 * don't waste time probing another function. 
-			 * Skip to next device. 
-			 */
+		if ((PCI_FUNC(devfn) == 0x00) && 
+			(!dev || (dev->enabled && ((dev->hdr_type & 0x80) != 0x80))))
+		{
 			devfn += 0x07;
 		}
 	}
 	post_code(0x25);
 
+	/* Die if any leftover Static devices are are found.  
+	 * There's probably a problem in the Config.lb.
+	*/
+	if(old_devices) {
+		device_t left;
+		for(left = old_devices; left; left = left->sibling) {
+			printk_debug("%s\n", dev_path(left));
+		}
+		die("Left over static devices.  Check your Config.lb\n");
+	}
+
 	/* For all children that implement scan_bus (i.e. bridges)
 	 * scan the bus behind that child.
 	 */
-	for (child = bus->children; child; child = child->sibling) {
-		if (!child->enabled ||
-		    !child->ops || 
-		    !child->ops->scan_bus) 
-		{
-			continue;
-		}
-		max = child->ops->scan_bus(child, max);
+	for(child = bus->children; child; child = child->sibling) {
+		max = scan_bus(child, max);
 	}
 
 	/*
@@ -911,6 +1065,7 @@
 	return max;
 }
 
+
 /**
  * @brief Scan a PCI bridge and the buses behind the bridge.
  *
@@ -924,7 +1079,9 @@
  *
  * @return The maximum bus number found, after scanning all subordinate busses
  */
-unsigned int pci_scan_bridge(struct device *dev, unsigned int max)
+unsigned int do_pci_scan_bridge(struct device *dev, unsigned int max, 
+	unsigned int (*do_scan_bus)(struct bus *bus, 
+		unsigned min_devfn, unsigned max_devfn, unsigned int max))
 {
 	struct bus *bus;
 	uint32_t buses;
@@ -960,14 +1117,14 @@
 	 */
 	buses &= 0xff000000;
 	buses |= (((unsigned int) (dev->bus->secondary) << 0) |
-		  ((unsigned int) (bus->secondary) << 8) |
-		  ((unsigned int) (bus->subordinate) << 16));
+		((unsigned int) (bus->secondary) << 8) |
+		((unsigned int) (bus->subordinate) << 16));
 	pci_write_config32(dev, PCI_PRIMARY_BUS, buses);
 
 	/* Now we can scan all subordinate buses 
 	 * i.e. the bus behind the bridge.
 	 */
-	max = pci_scan_bus(bus, 0x00, 0xff, max);
+	max = do_scan_bus(bus, 0x00, 0xff, max);
 
 	/* We know the number of buses behind this bridge. Set the subordinate
 	 * bus number to its real value.
@@ -977,11 +1134,29 @@
 		((unsigned int) (bus->subordinate) << 16);
 	pci_write_config32(dev, PCI_PRIMARY_BUS, buses);
 	pci_write_config16(dev, PCI_COMMAND, cr);
-
+	
 	printk_spew("%s returns max %d\n", __func__, max);
 	return max;
 }
 
+/**
+ * @brief Scan a PCI bridge and the buses behind the bridge.
+ *
+ * Determine the existence of buses behind the bridge. Set up the bridge
+ * according to the result of the scan.
+ *
+ * This function is the default scan_bus() method for PCI bridge devices.
+ *
+ * @param dev pointer to the bridge device
+ * @param max the highest bus number assgined up to now
+ *
+ * @return The maximum bus number found, after scanning all subordinate busses
+ */
+unsigned int pci_scan_bridge(struct device *dev, unsigned int max)
+{
+	return do_pci_scan_bridge(dev, max, pci_scan_bus);
+}
+
 /*
     Tell the EISA int controller this int must be level triggered
     THIS IS A KLUDGE -- sorry, this needs to get cleaned up.
@@ -1026,7 +1201,8 @@
 
     -kevinh@ispiri.com
 */
-void pci_assign_irqs(unsigned bus, unsigned slot, const unsigned char pIntAtoD[4])
+void pci_assign_irqs(unsigned bus, unsigned slot,
+	const unsigned char pIntAtoD[4])
 {
 	unsigned functNum;
 	device_t pdev;