Commit 0efd5aab authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

PCI: add struct pci_host_bridge_window with CPU/bus address offset 



Some PCI host bridges apply an address offset, so bus addresses on PCI are
different from CPU addresses.  This patch adds a way for architectures to
tell the PCI core about this offset.  For example:

    LIST_HEAD(resources);
    pci_add_resource_offset(&resources, host->io_space, host->io_offset);
    pci_add_resource_offset(&resources, host->mem_space, host->mem_offset);
    pci_scan_root_bus(parent, bus, ops, sysdata, &resources);

Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 5a21d70d

drivers/pci/bus.c

+19 −11
Original line number Diff line number Diff line
@@ -18,28 +18,36 @@ 


#include "pci.h"



void pci_add_resource(struct list_head *resources, struct resource *res)

void pci_add_resource_offset(struct list_head *resources, struct resource *res,

			     resource_size_t offset)

{

	struct pci_bus_resource *bus_res;

	struct pci_host_bridge_window *window;



	bus_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);

	if (!bus_res) {

		printk(KERN_ERR "PCI: can't add bus resource %pR\n", res);

	window = kzalloc(sizeof(struct pci_host_bridge_window), GFP_KERNEL);

	if (!window) {

		printk(KERN_ERR "PCI: can't add host bridge window %pR\n", res);

		return;

	}



	bus_res->res = res;

	list_add_tail(&bus_res->list, resources);

	window->res = res;

	window->offset = offset;

	list_add_tail(&window->list, resources);

}

EXPORT_SYMBOL(pci_add_resource_offset);



void pci_add_resource(struct list_head *resources, struct resource *res)

{

	pci_add_resource_offset(resources, res, 0);

}

EXPORT_SYMBOL(pci_add_resource);



void pci_free_resource_list(struct list_head *resources)

{

	struct pci_bus_resource *bus_res, *tmp;

	struct pci_host_bridge_window *window, *tmp;



	list_for_each_entry_safe(bus_res, tmp, resources, list) {

		list_del(&bus_res->list);

		kfree(bus_res);

	list_for_each_entry_safe(window, tmp, resources, list) {

		list_del(&window->list);

		kfree(window);

	}

}

EXPORT_SYMBOL(pci_free_resource_list);

drivers/pci/probe.c

+23 −9
Original line number Diff line number Diff line
@@ -1562,12 +1562,15 @@ unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus) 
struct pci_bus *pci_create_root_bus(struct device *parent, int bus,

		struct pci_ops *ops, void *sysdata, struct list_head *resources)

{

	int error, i;

	int error;

	struct pci_host_bridge *bridge;

	struct pci_bus *b, *b2;

	struct device *dev;

	struct pci_bus_resource *bus_res, *n;

	struct pci_host_bridge_window *window, *n;

	struct resource *res;

	resource_size_t offset;

	char bus_addr[64];

	char *fmt;



	bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);

	if (!bridge)
@@ -1617,19 +1620,30 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, 
	b->number = b->secondary = bus;



	bridge->bus = b;



	/* Add initial resources to the bus */

	list_for_each_entry_safe(bus_res, n, resources, list)

		list_move_tail(&bus_res->list, &b->resources);

	INIT_LIST_HEAD(&bridge->windows);



	if (parent)

		dev_info(parent, "PCI host bridge to bus %s\n", dev_name(&b->dev));

	else

		printk(KERN_INFO "PCI host bridge to bus %s\n", dev_name(&b->dev));



	pci_bus_for_each_resource(b, res, i) {

		if (res)

			dev_info(&b->dev, "root bus resource %pR\n", res);

	/* Add initial resources to the bus */

	list_for_each_entry_safe(window, n, resources, list) {

		list_move_tail(&window->list, &bridge->windows);

		res = window->res;

		offset = window->offset;

		pci_bus_add_resource(b, res, 0);

		if (offset) {

			if (resource_type(res) == IORESOURCE_IO)

				fmt = " (bus address [%#06llx-%#06llx])";

			else

				fmt = " (bus address [%#010llx-%#010llx])";

			snprintf(bus_addr, sizeof(bus_addr), fmt,

				 (unsigned long long) (res->start - offset),

				 (unsigned long long) (res->end - offset));

		} else

			bus_addr[0] = '\0';

		dev_info(&b->dev, "root bus resource %pR%s\n", res, bus_addr);

	}



	down_write(&pci_bus_sem);

include/linux/pci.h

+9 −0
Original line number Diff line number Diff line
@@ -368,9 +368,16 @@ static inline int pci_channel_offline(struct pci_dev *pdev) 
	return (pdev->error_state != pci_channel_io_normal);

}



struct pci_host_bridge_window {

	struct list_head list;

	struct resource *res;		/* host bridge aperture (CPU address) */

	resource_size_t offset;		/* bus address + offset = CPU address */

};



struct pci_host_bridge {

	struct list_head list;

	struct pci_bus *bus;		/* root bus */

	struct list_head windows;	/* pci_host_bridge_windows */

};



/*
@@ -901,6 +908,8 @@ void pci_release_selected_regions(struct pci_dev *, int); 


/* drivers/pci/bus.c */

void pci_add_resource(struct list_head *resources, struct resource *res);

void pci_add_resource_offset(struct list_head *resources, struct resource *res,

			     resource_size_t offset);

void pci_free_resource_list(struct list_head *resources);

void pci_bus_add_resource(struct pci_bus *bus, struct resource *res, unsigned int flags);

struct resource *pci_bus_resource_n(const struct pci_bus *bus, int n);

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