path: root/drivers/pci/setup-bus.c

/*
 *	drivers/pci/setup-bus.c
 *
 * Extruded from code written by
 *      Dave Rusling (david.rusling@reo.mts.dec.com)
 *      David Mosberger (davidm@cs.arizona.edu)
 *	David Miller (davem@redhat.com)
 *
 * Support routines for initializing a PCI subsystem.
 */

/*
 * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 *	     PCI-PCI bridges cleanup, sorted resource allocation.
 * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
 *	     Converted to allocation in 3 passes, which gives
 *	     tighter packing. Prefetchable range support.
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/cache.h>
#include <linux/slab.h>
#include "pci.h"

struct resource_list_x {
	struct resource_list_x *next;
	struct resource *res;
	struct pci_dev *dev;
	resource_size_t start;
	resource_size_t end;
	unsigned long flags;
};

static void add_to_failed_list(struct resource_list_x *head,
				 struct pci_dev *dev, struct resource *res)
{
	struct resource_list_x *list = head;
	struct resource_list_x *ln = list->next;
	struct resource_list_x *tmp;

	tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
	if (!tmp) {
		pr_warning("add_to_failed_list: kmalloc() failed!\n");
		return;
	}

	tmp->next = ln;
	tmp->res = res;
	tmp->dev = dev;
	tmp->start = res->start;
	tmp->end = res->end;
	tmp->flags = res->flags;
	list->next = tmp;
}

static void free_failed_list(struct resource_list_x *head)
{
	struct resource_list_x *list, *tmp;

	for (list = head->next; list;) {
		tmp = list;
		list = list->next;
		kfree(tmp);
	}

	head->next = NULL;
}

static void __dev_sort_resources(struct pci_dev *dev,
				 struct resource_list *head)
{
	u16 class = dev->class >> 8;

	/* Don't touch classless devices or host bridges or ioapics.  */
	if (class == PCI_CLASS_NOT_DEFINED || class == PCI_CLASS_BRIDGE_HOST)
		return;

	/* Don't touch ioapic devices already enabled by firmware */
	if (class == PCI_CLASS_SYSTEM_PIC) {
		u16 command;
		pci_read_config_word(dev, PCI_COMMAND, &command);
		if (command & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY))
			return;
	}

	pdev_sort_resources(dev, head);
}

static void __assign_resources_sorted(struct resource_list *head,
				 struct resource_list_x *fail_head)
{
	struct resource *res;
	struct resource_list *list, *tmp;
	int idx;

	for (list = head->next; list;) {
		res = list->res;
		idx = res - &list->dev->resource[0];

		if (pci_assign_resource(list->dev, idx)) {
			if (fail_head && !pci_is_root_bus(list->dev->bus)) {
				/*
				 * if the failed res is for ROM BAR, and it will
				 * be enabled later, don't add it to the list
				 */
				if (!((idx == PCI_ROM_RESOURCE) &&
				      (!(res->flags & IORESOURCE_ROM_ENABLE))))
					add_to_failed_list(fail_head, list->dev, res);
			}
			res->start = 0;
			res->end = 0;
			res->flags = 0;
		}
		tmp = list;
		list = list->next;
		kfree(tmp);
	}
}

static void pdev_assign_resources_sorted(struct pci_dev *dev,
				 struct resource_list_x *fail_head)
{
	struct resource_list head;

	head.next = NULL;
	__dev_sort_resources(dev, &head);
	__assign_resources_sorted(&head, fail_head);

}

static void pbus_assign_resources_sorted(const struct pci_bus *bus,
					 struct resource_list_x *fail_head)
{
	struct pci_dev *dev;
	struct resource_list head;

	head.next = NULL;
	list_for_each_entry(dev, &bus->devices,