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;
	resource_size_t add_size;
	unsigned long flags;
};

#define free_list(type, head) do {                      \
	struct type *list, *tmp;			\
	for (list = (head)->next; list;) {		\
		tmp = list;				\
		list = list->next;			\
		kfree(tmp);				\
	}						\
	(head)->next = NULL;				\
} while (0)

/**
 * add_to_list() - add a new resource tracker to the list
 * @head:	Head of the list
 * @dev:	device corresponding to which the resource
 *		belongs
 * @res:	The resource to be tracked
 * @add_size:	additional size to be optionally added
 *              to the resource
 */
static void add_to_list(struct resource_list_x *head,
		 struct pci_dev *dev, struct resource *res,
		 resource_size_t add_size)
{
	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_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;
	tmp->add_size = add_size;
	list->next = tmp;
}

static void add_to_failed_list(struct resource_list_x *head,
				struct pci_dev *dev, struct resource *res)
{
	add_to_list(head, dev, res, 0);
}

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 inline void reset_resource(struct resource *res)
{
	res->start = 0;
	res->end = 0;
	res->flags = 0;
}

/**
 * adjust_resources_sorted() - satisfy any additional resource requests
 *
 * @add_head : head of the list tracking requests requiring additional
 *             resources
 * @head     : head of the list tracking requests with allocated
 *             resources
 *
 * Walk through each element of the add_head and try to procure
 * additional resources for the element, provided the element
 * is in the head list.
 */
static void adjust_resources_sorted(struct resource_list_x *add_head,
		struct resource_list *head)
{
	struct resource <