- Initial checkin of the freebios2 tree


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@784 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/devices/device.c b/src/devices/device.c
new file mode 100644
index 0000000..ffc7253
--- /dev/null
+++ b/src/devices/device.c
@@ -0,0 +1,423 @@
+/*
+ *      (c) 1999--2000 Martin Mares <mj@suse.cz>
+ *      (c) 2003 Eric Biederman <ebiederm@xmission.com>
+ */
+/* lots of mods by ron minnich (rminnich@lanl.gov), with 
+ * the final architecture guidance from Tom Merritt (tjm@codegen.com)
+ * In particular, we changed from the one-pass original version to 
+ * Tom's recommended multiple-pass version. I wasn't sure about doing 
+ * it with multiple passes, until I actually started doing it and saw
+ * the wisdom of Tom's recommendations ...
+ *
+ * Lots of cleanups by Eric Biederman to handle bridges, and to
+ * handle resource allocation for non-pci devices.
+ */
+
+#include <console/console.h>
+#include <bitops.h>
+#include <device.h>
+#include <arch/io.h>
+#include <pci.h>
+
+/**
+ * This is the root of the device tree. A PCI tree always has 
+ * one bus, bus 0. Bus 0 contains devices and bridges. 
+ */
+struct device dev_root;
+/* Linked list of ALL devices */
+struct device *all_devices = 0;
+/* pointer to the last device */
+static struct device **last_dev_p = &all_devices;
+
+#define DEVICE_MEM_HIGH  0xFEC00000UL /* Reserve 20M for the system */
+#define DEVICE_IO_START 0x1000
+
+
+unsigned long device_memory_base;
+
+
+/* Append a new device to the global device chain.
+ * The chain is used to find devices once everything is set up.
+ */
+void append_device(struct device *dev)
+{
+	*last_dev_p = dev;
+	last_dev_p = &dev->next;
+}
+
+
+/** round a number to an alignment. 
+ * @param val the starting value
+ * @param roundup Alignment as a power of two
+ * @returns rounded up number
+ */
+static unsigned long round(unsigned long val, unsigned long roundup)
+{
+	/* ROUNDUP MUST BE A POWER OF TWO. */
+	unsigned long inverse;
+	inverse = ~(roundup - 1);
+	val += (roundup - 1);
+	val &= inverse;
+	return val;
+}
+
+static unsigned long round_down(unsigned long val, unsigned long round_down)
+{
+	/* ROUND_DOWN MUST BE A POWER OF TWO. */
+	unsigned long inverse;
+	inverse = ~(round_down - 1);
+	val &= inverse;
+	return val;
+}
+
+
+/** Read the resources on all devices of a given bus.
+ * @param bus bus to read the resources on.
+ */
+static void read_resources(struct device *bus)
+{
+	struct device *curdev;
+
+	
+	/* Walk through all of the devices and find which resources they need. */
+	for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+		if (curdev->resources > 0) {
+			continue;
+		}
+		curdev->ops->read_resources(curdev);
+	}
+}
+
+static struct device *largest_resource(struct device *bus, struct resource **result_res,
+	unsigned long type_mask, unsigned long type)
+{
+	struct device *curdev;
+	struct device *result_dev = 0;
+	struct resource *last = *result_res;
+	struct resource *result = 0;
+	int seen_last = 0;
+	for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+		int i;
+		for(i = 0; i < curdev->resources; i++) {
+			struct resource *resource = &curdev->resource[i];
+			/* If it isn't the right kind of resource ignore it */
+			if ((resource->flags & type_mask) != type) {
+				continue;
+			}
+			/* Be certain to pick the successor to last */
+			if (resource == last) {
+				seen_last = 1;
+				continue;
+			}
+			if (last && (
+				(last->align < resource->align) ||
+				((last->align == resource->align) &&
+					(last->size < resource->size)) ||
+				((last->align == resource->align) &&
+					(last->size == resource->size) &&
+					(!seen_last)))) {
+				continue;
+			}
+			if (!result || 
+				(result->align < resource->align) ||
+				((result->align == resource->align) &&
+					(result->size < resource->size))) {
+				result_dev = curdev;
+				result = resource;
+			}
+		}
+	}
+	*result_res = result;
+	return result_dev;
+}
+
+/* Compute allocate resources is the guts of the resource allocator.
+ * 
+ * The problem.
+ *  - Allocate resources locations for every device.
+ *  - Don't overlap, and follow the rules of bridges.
+ *  - Don't overlap with resources in fixed locations.
+ *  - Be efficient so we don't have ugly strategies.
+ *
+ * The strategy.
+ * - Devices that have fixed addresses are the minority so don't
+ *   worry about them too much.  Instead only use part of the address
+ *   space for devices with programmable addresses.  This easily handles
+ *   everything except bridges.
+ *
+ * - PCI devices are required to have thier sizes and their alignments
+ *   equal.  In this case an optimal solution to the packing problem
+ *   exists.  Allocate all devices from highest alignment to least
+ *   alignment or vice versa.  Use this.
+ *
+ * - So we can handle more than PCI run two allocation passes on
+ *   bridges.  The first to see how large the resources are behind
+ *   the bridge, and what their alignment requirements are.  The
+ *   second to assign a safe address to the devices behind the
+ *   bridge.  This allows me to treat a bridge as just a device with 
+ *   a couple of resources, and not need to special case it in the
+ *   allocator.  Also this allows handling of other types of bridges.
+ *
+ */
+
+void compute_allocate_resource(
+	struct device *bus,
+	struct resource *bridge,
+	unsigned long type_mask,
+	unsigned long type)
+{
+	struct device *dev;
+	struct resource *resource;
+	unsigned long base;
+	unsigned long align, min_align;
+	min_align = 0;
+	base = bridge->base;
+
+	/* We want different minimum alignments for different kinds of
+	 * resources.  These minimums are not device type specific
+	 * but resource type specific.
+	 */
+	if (bridge->flags & IORESOURCE_IO) {
+		min_align = log2(DEVICE_IO_ALIGN);
+	}
+	if (bridge->flags & IORESOURCE_MEM) {
+		min_align = log2(DEVICE_MEM_ALIGN);
+	}
+
+	printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d\n", 
+		bus->bus->secondary,
+		PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn),
+		(bridge->flags & IORESOURCE_IO)? "io":
+		(bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
+		base, bridge->size, bridge->align, bridge->gran);
+
+	/* Make certain I have read in all of the resources */
+	read_resources(bus);
+
+	/* Remember I haven't found anything yet. */
+	resource = 0;
+
+	/* Walk through all the devices on the current bus and compute the addresses */
+	while((dev = largest_resource(bus, &resource, type_mask, type))) {
+		unsigned long size;
+		/* Do NOT I repeat do not ignore resources which have zero size.
+		 * If they need to be ignored dev->read_resources should not even
+		 * return them.   Some resources must be set even when they have
+		 * no size.  PCI bridge resources are a good example of this.
+		 */
+
+		/* Propogate the resource alignment to the bridge register  */
+		if (resource->align > bridge->align) {
+			bridge->align = resource->align;
+		}
+
+		/* Make certain we are dealing with a good minimum size */
+		size = resource->size;
+		align = resource->align;
+		if (align < min_align) {
+			align = min_align;
+		}
+		if (resource->flags & IORESOURCE_IO) {
+			/* Don't allow potential aliases over the
+			 * legacy pci expansion card addresses.
+			 */
+			if ((base > 0x3ff) && ((base & 0x300) != 0)) {
+				base = (base & ~0x3ff) + 0x400;
+			}
+			/* Don't allow allocations in the VGA IO range.
+			 * PCI has special cases for that.
+			 */
+			else if ((base >= 0x3b0) && (base <= 0x3df)) {
+				base = 0x3e0;
+			}
+		}
+		if (((round(base, 1UL << align) + size) -1) <= resource->limit) {
+			/* base must be aligned to size */
+			base = round(base, 1UL << align);
+			resource->base = base;
+			resource->flags |= IORESOURCE_SET;
+			base += size;
+			
+			printk_spew(
+				"DEV: %02x:%02x.%01x %02x *  [0x%08lx - 0x%08lx] %s\n",
+				dev->bus->secondary, 
+				PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+				resource->index, 
+				resource->base, resource->base + resource->size -1,
+				(resource->flags & IORESOURCE_IO)? "io":
+				(resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem");
+		}
+
+	}
+	/* A pci bridge resource does not need to be a power
+	 * of two size, but it does have a minimum granularity.
+	 * Round the size up to that minimum granularity so we
+	 * know not to place something else at an address postitively
+	 * decoded by the bridge.
+	 */
+	bridge->size = round(base, 1UL << bridge->gran) - bridge->base;
+
+	printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d done\n", 
+		bus->bus->secondary,
+		PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn),
+		(bridge->flags & IORESOURCE_IO)? "io":
+		(bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
+		base, bridge->size, bridge->align, bridge->gran);
+
+
+}
+
+static void allocate_vga_resource(void)
+{
+	/* FIXME handle the VGA pallette snooping */
+	struct device *dev, *vga, *bus;
+	bus = vga = 0;
+	for(dev = all_devices; dev; dev = dev->next) {
+		uint32_t class_revision;
+		pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_revision);
+		if (((class_revision >> 24) == 0x03) && 
+		    ((class_revision >> 16) != 0x380)) {
+			if (!vga) {
+				printk_debug("Allocating VGA resource\n");
+				vga = dev;
+			}
+			if (vga == dev) {
+				/* All legacy VGA cards have MEM & I/O space registers */
+				dev->command |= PCI_COMMAND_MEMORY | PCI_COMMAND_IO;
+			} else {
+				/* It isn't safe to enable other VGA cards */
+				dev->command &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
+			}
+		}
+	}
+	if (vga) {
+		bus = vga->bus;
+	}
+	/* Now walk up the bridges setting the VGA enable */
+	while(bus) {
+		uint16_t ctrl;
+		pci_read_config_word(bus, PCI_BRIDGE_CONTROL, &ctrl);
+		ctrl |= PCI_BRIDGE_CTL_VGA;
+		pci_write_config_word(bus, PCI_BRIDGE_CONTROL, ctrl);
+		bus = (bus == bus->bus)? 0 : bus->bus;
+	} 
+}
+
+
+/** Assign the computed resources to the bridges and devices on the bus.
+ * Recurse to any bridges found on this bus first. Then do the devices
+ * on this bus. 
+ * @param bus Pointer to the structure for this bus
+ */ 
+void assign_resources(struct device *bus)
+{
+	struct device *curdev;
+
+	printk_debug("ASSIGN RESOURCES, bus %d\n", bus->secondary);
+
+	for (curdev = bus->children; curdev; curdev = curdev->sibling) {
+		curdev->ops->set_resources(curdev);
+	}
+	printk_debug("ASSIGNED RESOURCES, bus %d\n", bus->secondary);
+}
+
+static void enable_resources(struct device *bus)
+{
+	struct device *curdev;
+
+	/* Walk through the chain of all pci devices and enable them.
+	 * This is effectively a breadth first traversal so we should
+	 * not have enalbing ordering problems.
+	 */
+	for (curdev = all_devices; curdev; curdev = curdev->next) {
+		uint16_t command;
+		pci_read_config_word(curdev, PCI_COMMAND, &command);
+		command |= curdev->command;
+		printk_debug("DEV: %02x:%02x.%01x cmd <- %02x\n",
+			curdev->bus->secondary,
+			PCI_SLOT(curdev->devfn), PCI_FUNC(curdev->devfn),
+			command);
+		pci_write_config_word(curdev, PCI_COMMAND, command);
+	}
+}
+
+/** Enumerate the resources on the PCI by calling pci_init
+ */
+void dev_enumerate(void)
+{
+	struct device *root;
+	printk_info("Enumerating buses...");
+	root = &dev_root;
+	if (!root->ops) {
+		root->ops = &default_pci_ops_root;
+	}
+	root->subordinate = root->ops->scan_bus(root, 0);
+	printk_info("done\n");
+}
+
+/** Starting at the root, compute what resources are needed and allocate them. 
+ * I/O starts at PCI_IO_START. Since the assignment is hierarchical we
+ * set the values into the dev_root struct. 
+ */
+void dev_configure(void)
+{
+	struct device *root = &dev_root;
+	printk_info("Allocating resources...");
+	printk_debug("\n");
+
+
+	root->ops->read_resources(root);
+
+	/* Make certain the io devices are allocated somewhere
+	 * safe.
+	 */
+	root->resource[0].base = DEVICE_IO_START;
+	root->resource[0].flags |= IORESOURCE_SET;
+	/* Now reallocate the pci resources memory with the
+	 * highest addresses I can manage.
+	 */
+	root->resource[1].base = 
+		round_down(DEVICE_MEM_HIGH - root->resource[1].size,
+			1UL << root->resource[1].align);
+	device_memory_base = root->resource[1].base;
+	root->resource[1].flags |= IORESOURCE_SET;
+	// now just set things into registers ... we hope ...
+	root->ops->set_resources(root);
+
+	allocate_vga_resource();
+
+	printk_info("done.\n");
+}
+
+/** Starting at the root, walk the tree and enable all devices/bridges. 
+ * What really happens is computed COMMAND bits get set in register 4
+ */
+void dev_enable(void)
+{
+	printk_info("Enabling resourcess...");
+
+	/* now enable everything. */
+	enable_resources(&dev_root);
+	printk_info("done.\n");
+}
+
+/** Starting at the root, walk the tree and call a driver to
+ *  do device specific setup.
+ */
+void dev_initialize(void)
+{
+	struct device *dev;
+
+	printk_info("Initializing devices...\n");
+	for (dev = all_devices; dev; dev = dev->next) {
+		if (dev->ops->init) {
+			printk_debug("PCI: %02x:%02x.%01x init\n",
+				dev->bus->secondary,
+				PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
+			dev->ops->init(dev);
+		}
+	}
+	printk_info("Devices initialized\n");
+}
+
+
diff --git a/src/devices/device_util.c b/src/devices/device_util.c
new file mode 100644
index 0000000..fdaa20d
--- /dev/null
+++ b/src/devices/device_util.c
@@ -0,0 +1,56 @@
+#include <console/console.h>
+#include <device.h>
+
+/**
+ * Given a bus and a devfn number, find the device structure
+ * @param bus The bus number
+ * @param devfn a device/function number
+ * @return pointer to the device structure
+ */
+struct device *dev_find_slot(unsigned int bus, unsigned int devfn)
+{
+	struct device *dev;
+
+	for (dev = all_devices; dev; dev = dev->next)
+		if (dev->bus->secondary == bus && dev->devfn == devfn)
+			break;
+	return dev;
+}
+
+/** Find a device of a given vendor and type
+ * @param vendor Vendor ID (e.g. 0x8086 for Intel)
+ * @param device Device ID
+ * @param from Pointer to the device structure, used as a starting point
+ *        in the linked list of all_devices, which can be 0 to start at the 
+ *        head of the list (i.e. all_devices)
+ * @return Pointer to the device struct 
+ */
+struct device *dev_find_device(unsigned int vendor, unsigned int device, struct device *from)
+{
+	if (!from)
+		from = all_devices;
+	else
+		from = from->next;
+	while (from && (from->vendor != vendor || from->device != device))
+		from = from->next;
+	return from;
+}
+
+/** Find a device of a given class
+ * @param class Class of the device
+ * @param from Pointer to the device structure, used as a starting point
+ *        in the linked list of all_devices, which can be 0 to start at the 
+ *        head of the list (i.e. all_devices)
+ * @return Pointer to the device struct 
+ */
+struct device *dev_find_class(unsigned int class, struct device *from)
+{
+	if (!from)
+		from = all_devices;
+	else
+		from = from->next;
+	while (from && from->class != class)
+		from = from->next;
+	return from;
+}
+
diff --git a/src/devices/pci_device.c b/src/devices/pci_device.c
new file mode 100644
index 0000000..2b309a9
--- /dev/null
+++ b/src/devices/pci_device.c
@@ -0,0 +1,670 @@
+/*
+ *      PCI Bus Services, see include/linux/pci.h for further explanation.
+ *
+ *      Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
+ *      David Mosberger-Tang
+ *
+ *      Copyright 1997 -- 1999 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ *	
+ *	Copyright 2003 -- Eric Biederman <ebiederman@lnxi.com>
+ */
+
+#include <console/console.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <bitops.h>
+#include <pci.h>
+#include <pci_ids.h>
+#include <string.h>
+
+static unsigned int pci_scan_bridge(struct device *bus, unsigned int max);
+
+/** 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
+ * @param index     Address of the pci configuration register
+ */
+static void pci_get_resource(struct device *dev, struct resource *resource, unsigned long index)
+{
+	uint32_t addr, size, base;
+	unsigned long type;
+
+	/* Initialize the resources to nothing */
+	resource->base = 0;
+	resource->size = 0;
+	resource->align = 0;
+	resource->gran = 0;
+	resource->limit = 0;
+	resource->flags = 0;
+	resource->index = index;
+
+	pci_read_config_dword(dev, index, &addr);
+	if (addr == 0xffffffffUL)
+		return;
+
+	/* FIXME: more consideration for 64-bit PCI devices,
+	 * we currently detect their size but otherwise
+	 * treat them as 32-bit resources
+	 */
+	/* get the size */
+	pci_write_config_dword(dev, index, ~0);
+	pci_read_config_dword(dev,  index, &size);
+
+	/* get the minimum value the bar can be set to */
+	pci_write_config_dword(dev, index, 0);
+	pci_read_config_dword(dev, index, &base);
+
+	/* restore addr */
+	pci_write_config_dword(dev, index, addr);
+
+	/*
+	 * some broken hardware has read-only registers that do not 
+	 * really size correctly. You can tell this if addr == size
+	 * Example: the acer m7229 has BARs 1-4 normally read-only. 
+	 * so BAR1 at offset 0x10 reads 0x1f1. If you size that register
+	 * by writing 0xffffffff to it, it will read back as 0x1f1 -- a 
+	 * violation of the spec. 
+	 * We catch this case and ignore it by settting size and type to 0.
+	 * This incidentally catches the common case where registers 
+	 * read back as 0 for both address and size. 
+	 */
+	if ((addr == size) && (addr == base)) {
+		if (size != 0) {
+			printk_debug(
+				"PCI: %02x:%02x.%01x register %02x(%08x), read-only ignoring it\n",
+				dev->bus->secondary,
+				PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+				index, addr);
+		}
+		resource->flags = 0;
+	}
+	/* Now compute the actual size, See PCI Spec 6.2.5.1 ...  */
+	else if (size & PCI_BASE_ADDRESS_SPACE_IO) {
+		type = size & (~PCI_BASE_ADDRESS_IO_MASK);
+		/* BUG! Top 16 bits can be zero (or not) 
+		 * So set them to 0xffff so they go away ...
+		 */
+		resource->size = (~((size | 0xffff0000) & PCI_BASE_ADDRESS_IO_MASK)) +1;
+		resource->align = log2(resource->size);
+		resource->gran = resource->align;
+		resource->flags = IORESOURCE_IO;
+		resource->limit = 0xffff;
+	} 
+	else {
+		/* A Memory mapped base address */
+		type = size & (~PCI_BASE_ADDRESS_MEM_MASK);
+		resource->size = (~(size &PCI_BASE_ADDRESS_MEM_MASK)) +1;
+		resource->align = log2(resource->size);
+		resource->gran = resource->align;
+		resource->flags = IORESOURCE_MEM;
+		if (type & PCI_BASE_ADDRESS_MEM_PREFETCH) {
+			resource->flags |= IORESOURCE_PREFETCH;
+		}
+		type &= PCI_BASE_ADDRESS_MEM_TYPE_MASK;
+		if (type == PCI_BASE_ADDRESS_MEM_TYPE_32) {
+			/* 32bit limit */
+			resource->limit = 0xffffffffUL;
+		}
+		else if (type == PCI_BASE_ADDRESS_MEM_TYPE_1M) {
+			/* 1MB limit */
+			resource->limit = 0x000fffffUL;
+		}
+		else if (type == PCI_BASE_ADDRESS_MEM_TYPE_64) {
+			unsigned long index_hi;
+			/* 64bit limit 
+			 * For now just treat this as a 32bit limit
+			 */
+			index_hi = index + 4;
+			resource->limit = 0xffffffffUL;
+			resource->flags |= IORESOURCE_PCI64;
+			pci_read_config_dword( dev, index_hi, &addr);
+			/* get the extended size */
+			pci_write_config_dword(dev, index_hi, 0xffffffffUL);
+			pci_read_config_dword( dev, index_hi, &size);
+
+			/* get the minimum value the bar can be set to */
+			pci_write_config_dword(dev, index_hi, 0);
+			pci_read_config_dword(dev,  index_hi, &base);
+
+			/* restore addr */
+			pci_write_config_dword(dev, index_hi, addr);
+			
+			if ((size == 0xffffffff) && (base == 0)) {
+				/* Clear the top half of the bar */
+				pci_write_config_dword(dev, index_hi, 0);
+			}
+			else {
+				printk_err("PCI: %02x:%02x.%01x Unable to handle 64-bit address\n",
+					dev->bus->secondary, 
+					PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
+				resource->flags = IORESOURCE_PCI64;
+			}
+		} 
+		else {
+			/* Invalid value */
+			resource->flags = 0;
+		}
+	}
+	/* dev->size holds the flags... */
+	return;
+}
+
+/** 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 int reg;
+	unsigned long index;
+
+	reg = dev->resources;
+	for(index = PCI_BASE_ADDRESS_0; 
+	    (reg < MAX_RESOURCES) && (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) {
+		struct resource *resource;
+		resource = &dev->resource[reg];
+		pci_get_resource(dev, resource, index);
+		reg += (resource->flags & (IORESOURCE_IO | IORESOURCE_MEM))? 1:0;
+		index += (resource->flags & IORESOURCE_PCI64)?8:4;
+	}
+	dev->resources = reg;
+}
+
+
+static void pci_bridge_read_bases(struct device *dev)
+{
+	unsigned int reg = dev->resources;
+
+	/* FIXME handle bridges without some of the optional resources */
+
+	/* Initialize the io space constraints on the current bus */
+	dev->resource[reg].base  = 0;
+	dev->resource[reg].size  = 0;
+	dev->resource[reg].align = log2(PCI_IO_BRIDGE_ALIGN);
+	dev->resource[reg].gran  = log2(PCI_IO_BRIDGE_ALIGN);
+	dev->resource[reg].limit = 0xffffUL;
+	dev->resource[reg].flags = IORESOURCE_IO | IORESOURCE_PCI_BRIDGE;
+	dev->resource[reg].index = PCI_IO_BASE;
+	compute_allocate_resource(dev, &dev->resource[reg],
+		IORESOURCE_IO, IORESOURCE_IO);
+	reg++;
+
+	/* Initiliaze the prefetchable memory constraints on the current bus */
+	dev->resource[reg].base = 0;
+	dev->resource[reg].size = 0;
+	dev->resource[reg].align = log2(PCI_MEM_BRIDGE_ALIGN);
+	dev->resource[reg].gran  = log2(PCI_MEM_BRIDGE_ALIGN);
+	dev->resource[reg].limit = 0xffffffffUL;
+	dev->resource[reg].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_PCI_BRIDGE;
+	dev->resource[reg].index = PCI_PREF_MEMORY_BASE;
+	compute_allocate_resource(dev, &dev->resource[reg],
+		IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+		IORESOURCE_MEM | IORESOURCE_PREFETCH);
+	reg++;
+
+	/* Initialize the memory resources on the current bus */
+	dev->resource[reg].base = 0;
+	dev->resource[reg].size = 0;
+	dev->resource[reg].align = log2(PCI_MEM_BRIDGE_ALIGN);
+	dev->resource[reg].gran  = log2(PCI_MEM_BRIDGE_ALIGN);
+	dev->resource[reg].limit = 0xffffffffUL;
+	dev->resource[reg].flags = IORESOURCE_MEM | IORESOURCE_PCI_BRIDGE;
+	dev->resource[reg].index = PCI_MEMORY_BASE;
+	compute_allocate_resource(dev, &dev->resource[reg],
+		IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+		IORESOURCE_MEM);
+	reg++;
+
+	dev->resources = reg;
+}
+
+
+static void pci_dev_read_resources(struct device *dev)
+{
+	uint32_t addr;
+	dev->resources = 0;
+	memset(&dev->resource[0], 0, sizeof(dev->resource));
+	pci_read_bases(dev, 6);
+	pci_read_config_dword(dev, PCI_ROM_ADDRESS, &addr);
+	dev->rom_address = (addr == 0xffffffff)? 0 : addr;
+}
+
+static void pci_bus_read_resources(struct device *dev)
+{
+	uint32_t addr;
+	dev->resources = 0;
+	memset(&dev->resource[0], 0, sizeof(dev->resource));
+	pci_bridge_read_bases(dev);
+	pci_read_bases(dev, 2);
+	
+	pci_read_config_dword(dev, PCI_ROM_ADDRESS1, &addr);
+	dev->rom_address = (addr == 0xffffffff)? 0 : addr;
+
+}
+
+
+static void pci_set_resource(struct device *dev, struct resource *resource)
+{
+	unsigned long base, limit;
+	unsigned long bridge_align = PCI_MEM_BRIDGE_ALIGN;
+	unsigned char buf[10];
+	
+	/* Make certain the resource has actually been set */
+	if (!(resource->flags & IORESOURCE_SET)) {
+#if 1
+		printk_err("ERROR: %02x:%02x.%01x %02x not allocated\n",
+			dev->bus->secondary,
+			PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+			resource->index);
+#endif
+		return;
+	}
+
+	/* Only handle PCI memory and IO resources for now */
+	if (!(resource->flags & (IORESOURCE_MEM |IORESOURCE_IO)))
+		return;
+	
+	if (resource->flags & IORESOURCE_MEM) {
+		dev->command |= PCI_COMMAND_MEMORY;
+		bridge_align = PCI_MEM_BRIDGE_ALIGN;
+	}
+	if (resource->flags & IORESOURCE_IO) {
+		dev->command |= PCI_COMMAND_IO;
+		bridge_align = PCI_IO_BRIDGE_ALIGN;
+	}
+	if (resource->flags & IORESOURCE_PCI_BRIDGE) {
+		dev->command |= PCI_COMMAND_MASTER;
+	}
+	/* Get the base address */
+	base = resource->base;
+	
+	/* Get the limit (rounded up) */
+	limit = base + ((resource->size + bridge_align - 1UL) & ~(bridge_align -1)) -1UL;
+	
+	if (!(resource->flags & IORESOURCE_PCI_BRIDGE)) {
+		/*
+		 * some chipsets allow us to set/clear the IO bit. 
+		 * (e.g. VIA 82c686a.) So set it to be safe)
+		 */
+		limit = base + resource->size -1;
+		if (resource->flags & IORESOURCE_IO) {
+			base |= PCI_BASE_ADDRESS_SPACE_IO;
+		}
+		pci_write_config_dword(dev, resource->index, base & 0xffffffff);
+		if (resource->flags & IORESOURCE_PCI64) {
+			/* FIXME handle real 64bit base addresses */
+			pci_write_config_dword(dev, resource->index + 4, 0);
+		}
+	}
+	else if (resource->index == PCI_IO_BASE) {
+		/* set the IO ranges
+		 * WARNING: we don't really do 32-bit addressing for IO yet! 
+		 */
+		compute_allocate_resource(dev, resource, 
+			IORESOURCE_IO, IORESOURCE_IO);
+		pci_write_config_byte(dev, PCI_IO_BASE,  base >> 8);
+		pci_write_config_byte(dev, PCI_IO_LIMIT, limit >> 8);
+	}
+	else if (resource->index == PCI_MEMORY_BASE) {
+		/* set the memory range
+		 */
+		compute_allocate_resource(dev, resource,
+			IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+			IORESOURCE_MEM);
+		pci_write_config_word(dev, PCI_MEMORY_BASE, base >> 16);
+		pci_write_config_word(dev, PCI_MEMORY_LIMIT, limit >> 16);
+	}
+	else if (resource->index == PCI_PREF_MEMORY_BASE) {
+		/* set the prefetchable memory range
+		 * WARNING: we don't really do 64-bit addressing for prefetchable memory yet!
+		 */
+		compute_allocate_resource(dev, resource,
+			IORESOURCE_MEM | IORESOURCE_PREFETCH, 
+			IORESOURCE_MEM | IORESOURCE_PREFETCH);
+		pci_write_config_word(dev, PCI_PREF_MEMORY_BASE,  base >> 16);
+		pci_write_config_word(dev, PCI_PREF_MEMORY_LIMIT, limit >> 16);
+	}
+	else {
+		printk_err("ERROR: invalid resource->index %x\n",
+			resource->index);
+	}
+	buf[0] = '\0';
+	if (resource->flags & IORESOURCE_PCI_BRIDGE) {
+		sprintf(buf, "bus %d ", dev->secondary);
+	}
+	
+	printk_debug(
+		"PCI: %02x:%02x.%01x %02x <- [0x%08lx - 0x%08lx] %s%s\n",
+		dev->bus->secondary, 
+		PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+		resource->index, 
+		resource->base, limit,
+		buf,
+		(resource->flags & IORESOURCE_IO)? "io":
+		(resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem");
+	return;
+}
+
+static void pci_dev_set_resources(struct device *dev)
+{
+	struct resource *resource, *last;
+	uint8_t line;
+
+	last = &dev->resource[dev->resources];
+
+	for(resource = &dev->resource[0]; resource < last; resource++) {
+		pci_set_resource(dev, resource);
+	}
+	if (dev->children) {
+		assign_resources(dev);
+	}
+
+	/* set a default latency timer */
+	pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0x40);
+
+	/* set a default secondary latency timer */
+	if ((dev->hdr_type & 0x7f) == PCI_HEADER_TYPE_BRIDGE) {
+		pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER, 0x40);
+	}
+
+	/* zero the irq settings */
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &line);
+	if (line) {
+		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 0);
+	}
+	/* set the cache line size, so far 64 bytes is good for everyone */
+	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 64 >> 2);
+}
+
+struct device_operations default_pci_ops_dev = {
+	.read_resources = pci_dev_read_resources,
+	.set_resources = pci_dev_set_resources,
+	.init = 0,
+	.scan_bus = 0,
+};
+struct device_operations default_pci_ops_bus = {
+	.read_resources = pci_bus_read_resources,
+	.set_resources = pci_dev_set_resources,
+	.init = 0,
+	.scan_bus = pci_scan_bridge,
+};
+static void set_pci_ops(struct device *dev)
+{
+	struct pci_driver *driver;
+	if (dev->ops) {
+		return;
+	}
+	/* Look through the list of setup drivers and find one for
+	 * this pci device 
+	 */
+	for(driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) {
+		if ((driver->vendor == dev->vendor) &&
+			(driver->device = dev->device)) {
+			dev->ops = driver->ops;
+			break;
+		}
+	}
+	/* If I don't have a specific driver use the default operations */
+	switch(dev->hdr_type & 0x7f) {	/* header type */
+	case PCI_HEADER_TYPE_NORMAL:	/* standard header */
+		if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)
+			goto bad;
+		dev->ops = &default_pci_ops_dev;
+		break;
+	case PCI_HEADER_TYPE_BRIDGE:
+		if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI)
+			goto bad;
+		dev->ops = &default_pci_ops_bus;
+		break;
+	default:
+	bad:
+		printk_err("PCI: %02x:%02x.%01x [%04x/%04x/%06x] has unknown header "
+			"type %02x, ignoring.\n",
+			dev->bus->secondary, 
+			PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+			dev->vendor, dev->device, 
+			dev->class >> 8, dev->hdr_type);
+	}
+	return;
+}
+
+/**
+ * Given a bus and a devfn number, find the device structure
+ * @param bus The bus structure
+ * @param devfn a device/function number
+ * @return pointer to the device structure
+ */
+static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn)
+{
+	struct device *dev = 0;
+	for(; *list; list = &(*list)->sibling) {
+		if ((*list)->devfn == devfn) {
+			/* Unlink from the list */
+			dev = *list;
+			*list = (*list)->sibling;
+			dev->sibling = 0;
+			break;
+		}
+	}
+	return dev;
+}
+
+
+/** Scan the pci bus devices and bridges.
+ * @param pci_bus pointer to the bus structure
+ * @param max current bus number
+ * @return The maximum bus number found, after scanning all subordinate busses
+ */
+unsigned int pci_scan_bus(struct device *bus, unsigned int max)
+{
+	unsigned int devfn;
+	struct device *dev, **bus_last;
+	struct device *old_devices;
+	struct device *child;
+
+	printk_debug("PCI: pci_scan_bus for bus %d\n", bus->secondary);
+
+	old_devices = bus->children;
+	bus->children = 0;
+	bus_last = &bus->children;
+
+	post_code(0x24);
+	
+
+	/* probe all devices on this bus with some optimization for non-existance and 
+	   single funcion devices */
+	for (devfn = 0; devfn < 0xff; devfn++) {
+		struct device dummy;
+		uint32_t id, class;
+		uint8_t cmd, tmp, hdr_type;
+
+		/* First thing setup the device structure */
+		dev = pci_scan_get_dev(&old_devices, devfn);
+	
+		dummy.bus = bus;
+		dummy.devfn = devfn;
+		pci_read_config_dword(&dummy, PCI_VENDOR_ID, &id);
+		/* some broken boards return 0 if a slot is empty: */
+		if (!dev &&
+			(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;
+			}
+			/* multi function device, skip to next function */
+			continue;
+		}
+		pci_read_config_byte(&dummy, PCI_HEADER_TYPE, &hdr_type);
+		pci_read_config_dword(&dummy, PCI_CLASS_REVISION, &class);
+
+		if (!dev) {
+			if ((dev = malloc(sizeof(*dev))) == 0) {
+				printk_err("PCI: out of memory.\n");
+				continue;
+			}
+			memset(dev, 0, sizeof(*dev));
+		}
+
+		dev->bus = bus;
+		dev->devfn = devfn;
+		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;
+
+		/* non-destructively determine if device can be a master: */
+		pci_read_config_byte(dev, PCI_COMMAND, &cmd);
+		pci_write_config_byte(dev, PCI_COMMAND, cmd | PCI_COMMAND_MASTER);
+		pci_read_config_byte(dev, PCI_COMMAND, &tmp);
+
+		dev->master = ((tmp & PCI_COMMAND_MASTER) != 0);
+		pci_write_config_byte(dev, PCI_COMMAND, cmd);
+
+		/* 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.
+		 */
+		set_pci_ops(dev);
+		/* Kill the device if we don't have some pci operations for it */
+		if (!dev->ops) {
+			free(dev);
+			continue;
+		}
+		printk_debug("PCI: %02x:%02x.%01x [%04x/%04x]\n", 
+			bus->secondary, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn), 
+			dev->vendor, dev->device);
+
+		/* Put it into the global device chain. */
+		append_device(dev);
+
+		/* Now insert it into the list of devices held by the parent bus. */
+		*bus_last = dev;
+		bus_last = &dev->sibling;
+
+		if (PCI_FUNC(devfn) == 0x00 && (hdr_type & 0x80) != 0x80) {
+			/* if this is not a multi function device, don't waste time probe
+			   another function. Skip to next device. */
+			devfn += 0x07;
+		}
+	}
+	post_code(0x25);
+
+	for(child = bus->children; child; child = child->sibling) {
+		if (!child->ops->scan_bus)
+			continue;
+		max = child->ops->scan_bus(child, max);
+		
+	}
+	/*
+	 * We've scanned the bus and so we know all about what's on
+	 * the other side of any bridges that may be on this bus plus
+	 * any devices.
+	 *
+	 * Return how far we've got finding sub-buses.
+	 */
+	printk_debug("PCI: pci_scan_bus returning with max=%02x\n", max);
+	post_code(0x55);
+	return max;
+}
+
+/** Scan the bus, first for bridges and next for devices. 
+ * @param pci_bus pointer to the bus structure
+ * @return The maximum bus number found, after scanning all subordinate busses
+ */
+static unsigned int pci_scan_bridge(struct device *bus, unsigned int max)
+{
+	uint32_t buses;
+	uint16_t cr;
+	/* Set up the primary, secondary and subordinate bus numbers. We have
+	 * no idea how many buses are behind this bridge yet, so we set the
+	 * subordinate bus number to 0xff for the moment 
+	 */
+	bus->secondary = ++max;
+	bus->subordinate = 0xff;
+	
+	/* Clear all status bits and turn off memory, I/O and master enables. */
+	pci_read_config_word(bus, PCI_COMMAND, &cr);
+	pci_write_config_word(bus, PCI_COMMAND, 0x0000);
+	pci_write_config_word(bus, PCI_STATUS, 0xffff);
+
+	/*
+	 * Read the existing primary/secondary/subordinate bus
+	 * number configuration.
+	 */
+	pci_read_config_dword(bus, PCI_PRIMARY_BUS, &buses);
+
+	/* Configure the bus numbers for this bridge: the configuration
+	 * transactions will not be propagated by the bridge if it is not
+	 * correctly configured 
+	 */
+	buses &= 0xff000000;
+	buses |= (((unsigned int) (bus->bus->secondary) << 0) |
+		((unsigned int) (bus->secondary) << 8) |
+		((unsigned int) (bus->subordinate) << 16));
+	pci_write_config_dword(bus, PCI_PRIMARY_BUS, buses);
+	
+	/* Now we can scan all subordinate buses i.e. the bus hehind the bridge */
+	max = pci_scan_bus(bus, max);
+	
+	/* We know the number of buses behind this bridge. Set the subordinate
+	 *  bus number to its real value 
+	 */
+	bus->subordinate = max;
+	buses = (buses & 0xff00ffff) |
+		((unsigned int) (bus->subordinate) << 16);
+	pci_write_config_dword(bus, PCI_PRIMARY_BUS, buses);
+	pci_write_config_word(bus, PCI_COMMAND, cr);
+		
+	return max;
+}
+
+
+static void pci_root_read_resources(struct device *bus)
+{
+	int res = 0;
+	/* Initialize the system wide io space constraints */
+	bus->resource[res].base  = 0x400;
+	bus->resource[res].size  = 0;
+	bus->resource[res].align = 0;
+	bus->resource[res].gran  = 0;
+	bus->resource[res].limit = 0xffffUL;
+	bus->resource[res].flags = IORESOURCE_IO;
+	bus->resource[res].index = PCI_IO_BASE;
+	compute_allocate_resource(bus, &bus->resource[res], 
+		IORESOURCE_IO, IORESOURCE_IO);
+	res++;
+
+	/* Initialize the system wide memory resources constraints */
+	bus->resource[res].base  = 0;
+	bus->resource[res].size  = 0;
+	bus->resource[res].align = 0;
+	bus->resource[res].gran  = 0;
+	bus->resource[res].limit = 0xffffffffUL;
+	bus->resource[res].flags = IORESOURCE_MEM;
+	bus->resource[res].index = PCI_MEMORY_BASE;
+	compute_allocate_resource(bus, &bus->resource[res], 
+		IORESOURCE_MEM, IORESOURCE_MEM);
+	res++;
+
+	bus->resources = res;
+}
+static void pci_root_set_resources(struct device *bus)
+{
+	compute_allocate_resource(bus,
+		&bus->resource[0], IORESOURCE_IO, IORESOURCE_IO);
+	compute_allocate_resource(bus, 
+		&bus->resource[1], IORESOURCE_MEM, IORESOURCE_MEM);
+	assign_resources(bus);
+}
+
+struct device_operations default_pci_ops_root = {
+	.read_resources = pci_root_read_resources,
+	.set_resources = pci_root_set_resources,
+	.init = 0,
+	.scan_bus = pci_scan_bus,
+};
+