pci.c

底层驱动开发

/*
 * Port for PPC64 David Engebretsen, IBM Corp.
 * Contains common pci routines for ppc64 platform, pSeries and iSeries brands.
 * 
 * Copyright (C) 2003 Anton Blanchard <[e-mail]>, IBM
 *   Rework, based on alpha PCI code.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#undef DEBUG

#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/syscalls.h>

#include <asm/processor.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/machdep.h>
#include <asm/udbg.h>

#include "pci.h"

#ifdef DEBUG
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif

unsigned long pci_probe_only = 1;
unsigned long pci_assign_all_buses = 0;

/*
 * legal IO pages under MAX_ISA_PORT.  This is to ensure we don't touch
 * devices we don't have access to.
 */
unsigned long io_page_mask;

EXPORT_SYMBOL(io_page_mask);

#ifdef CONFIG_PPC_MULTIPLATFORM
static void fixup_resource(struct resource *res, struct pci_dev *dev);
static void do_bus_setup(struct pci_bus *bus);
#endif

unsigned int pcibios_assign_all_busses(void)
{
	return pci_assign_all_buses;
}

/* pci_io_base -- the base address from which io bars are offsets.
 * This is the lowest I/O base address (so bar values are always positive),
 * and it *must* be the start of ISA space if an ISA bus exists because
 * ISA drivers use hard coded offsets.  If no ISA bus exists a dummy
 * page is mapped and isa_io_limit prevents access to it.
 */
unsigned long isa_io_base;	/* NULL if no ISA bus */
EXPORT_SYMBOL(isa_io_base);
unsigned long pci_io_base;
EXPORT_SYMBOL(pci_io_base);

void iSeries_pcibios_init(void);

LIST_HEAD(hose_list);

struct dma_mapping_ops pci_dma_ops;
EXPORT_SYMBOL(pci_dma_ops);

int global_phb_number;		/* Global phb counter */

/* Cached ISA bridge dev. */
struct pci_dev *ppc64_isabridge_dev = NULL;

static void fixup_broken_pcnet32(struct pci_dev* dev)
{
	if ((dev->class>>8 == PCI_CLASS_NETWORK_ETHERNET)) {
		dev->vendor = PCI_VENDOR_ID_AMD;
		pci_write_config_word(dev, PCI_VENDOR_ID, PCI_VENDOR_ID_AMD);
	}
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TRIDENT, PCI_ANY_ID, fixup_broken_pcnet32);

void  pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
			      struct resource *res)
{
	unsigned long offset = 0;
	struct pci_controller *hose = pci_bus_to_host(dev->bus);

	if (!hose)
		return;

	if (res->flags & IORESOURCE_IO)
	        offset = (unsigned long)hose->io_base_virt - pci_io_base;

	if (res->flags & IORESOURCE_MEM)
		offset = hose->pci_mem_offset;

	region->start = res->start - offset;
	region->end = res->end - offset;
}

void pcibios_bus_to_resource(struct pci_dev *dev, struct resource *res,
			      struct pci_bus_region *region)
{
	unsigned long offset = 0;
	struct pci_controller *hose = pci_bus_to_host(dev->bus);

	if (!hose)
		return;

	if (res->flags & IORESOURCE_IO)
	        offset = (unsigned long)hose->io_base_virt - pci_io_base;

	if (res->flags & IORESOURCE_MEM)
		offset = hose->pci_mem_offset;

	res->start = region->start + offset;
	res->end = region->end + offset;
}

#ifdef CONFIG_HOTPLUG
EXPORT_SYMBOL(pcibios_resource_to_bus);
EXPORT_SYMBOL(pcibios_bus_to_resource);
#endif

/*
 * We need to avoid collisions with `mirrored' VGA ports
 * and other strange ISA hardware, so we always want the
 * addresses to be allocated in the 0x000-0x0ff region
 * modulo 0x400.
 *
 * Why? Because some silly external IO cards only decode
 * the low 10 bits of the IO address. The 0x00-0xff region
 * is reserved for motherboard devices that decode all 16
 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
 * but we want to try to avoid allocating at 0x2900-0x2bff
 * which might have be mirrored at 0x0100-0x03ff..
 */
void pcibios_align_resource(void *data, struct resource *res,
			    unsigned long size, unsigned long align)
{
	struct pci_dev *dev = data;
	struct pci_controller *hose = pci_bus_to_host(dev->bus);
	unsigned long start = res->start;
	unsigned long alignto;

	if (res->flags & IORESOURCE_IO) {
	        unsigned long offset = (unsigned long)hose->io_base_virt -
					pci_io_base;
		/* Make sure we start at our min on all hoses */
		if (start - offset < PCIBIOS_MIN_IO)
			start = PCIBIOS_MIN_IO + offset;

		/*
		 * Put everything into 0x00-0xff region modulo 0x400
		 */
		if (start & 0x300)
			start = (start + 0x3ff) & ~0x3ff;

	} else if (res->flags & IORESOURCE_MEM) {
		/* Make sure we start at our min on all hoses */
		if (start - hose->pci_mem_offset < PCIBIOS_MIN_MEM)
			start = PCIBIOS_MIN_MEM + hose->pci_mem_offset;

		/* Align to multiple of size of minimum base.  */
		alignto = max(0x1000UL, align);
		start = ALIGN(start, alignto);
	}

	res->start = start;
}

static DEFINE_SPINLOCK(hose_spinlock);

/*
 * pci_controller(phb) initialized common variables.
 */
void __devinit pci_setup_pci_controller(struct pci_controller *hose)
{
	memset(hose, 0, sizeof(struct pci_controller));

	spin_lock(&hose_spinlock);
	hose->global_number = global_phb_number++;
	list_add_tail(&hose->list_node, &hose_list);
	spin_unlock(&hose_spinlock);
}

static void __init pcibios_claim_one_bus(struct pci_bus *b)
{
	struct pci_dev *dev;
	struct pci_bus *child_bus;

	list_for_each_entry(dev, &b->devices, bus_list) {
		int i;

		for (i = 0; i < PCI_NUM_RESOURCES; i++) {
			struct resource *r = &dev->resource[i];

			if (r->parent || !r->start || !r->flags)
				continue;
			pci_claim_resource(dev, i);
		}
	}

	list_for_each_entry(child_bus, &b->children, node)
		pcibios_claim_one_bus(child_bus);
}

#ifndef CONFIG_PPC_ISERIES
static void __init pcibios_claim_of_setup(void)
{
	struct pci_bus *b;

	list_for_each_entry(b, &pci_root_buses, node)
		pcibios_claim_one_bus(b);
}
#endif

#ifdef CONFIG_PPC_MULTIPLATFORM
static u32 get_int_prop(struct device_node *np, const char *name, u32 def)
{
	u32 *prop;
	int len;

	prop = (u32 *) get_property(np, name, &len);
	if (prop && len >= 4)
		return *prop;
	return def;
}

static unsigned int pci_parse_of_flags(u32 addr0)
{
	unsigned int flags = 0;

	if (addr0 & 0x02000000) {
		flags = IORESOURCE_MEM | PCI_BASE_ADDRESS_SPACE_MEMORY;
		flags |= (addr0 >> 22) & PCI_BASE_ADDRESS_MEM_TYPE_64;
		flags |= (addr0 >> 28) & PCI_BASE_ADDRESS_MEM_TYPE_1M;
		if (addr0 & 0x40000000)
			flags |= IORESOURCE_PREFETCH
				 | PCI_BASE_ADDRESS_MEM_PREFETCH;
	} else if (addr0 & 0x01000000)
		flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
	return flags;
}

#define GET_64BIT(prop, i)	((((u64) (prop)[(i)]) << 32) | (prop)[(i)+1])

static void pci_parse_of_addrs(struct device_node *node, struct pci_dev *dev)
{
	u64 base, size;
	unsigned int flags;
	struct resource *res;
	u32 *addrs, i;
	int proplen;

	addrs = (u32 *) get_property(node, "assigned-addresses", &proplen);
	if (!addrs)
		return;
	for (; proplen >= 20; proplen -= 20, addrs += 5) {
		flags = pci_parse_of_flags(addrs[0]);
		if (!flags)
			continue;
		base = GET_64BIT(addrs, 1);
		size = GET_64BIT(addrs, 3);
		if (!size)
			continue;
		i = addrs[0] & 0xff;
		if (PCI_BASE_ADDRESS_0 <= i && i <= PCI_BASE_ADDRESS_5) {
			res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
		} else if (i == dev->rom_base_reg) {
			res = &dev->resource[PCI_ROM_RESOURCE];
			flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
		} else {
			printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
			continue;
		}
		res->start = base;
		res->end = base + size - 1;
		res->flags = flags;
		res->name = pci_name(dev);
		fixup_resource(res, dev);
	}
}

static struct pci_dev *of_create_pci_dev(struct device_node *node,
					 struct pci_bus *bus, int devfn)
{
	struct pci_dev *dev;
	const char *type;

	dev = kmalloc(sizeof(struct pci_dev), GFP_KERNEL);
	if (!dev)
		return NULL;
	type = get_property(node, "device_type", NULL);
	if (type == NULL)
		type = "";

	memset(dev, 0, sizeof(struct pci_dev));
	dev->bus = bus;
	dev->sysdata = node;
	dev->dev.parent = bus->bridge;
	dev->dev.bus = &pci_bus_type;
	dev->devfn = devfn;
	dev->multifunction = 0;		/* maybe a lie? */

	dev->vendor = get_int_prop(node, "vendor-id", 0xffff);
	dev->device = get_int_prop(node, "device-id", 0xffff);
	dev->subsystem_vendor = get_int_prop(node, "subsystem-vendor-id", 0);
	dev->subsystem_device = get_int_prop(node, "subsystem-id", 0);

	dev->cfg_size = 256; /*pci_cfg_space_size(dev);*/

	sprintf(pci_name(dev), "%04x:%02x:%02x.%d", pci_domain_nr(bus),
		dev->bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn));
	dev->class = get_int_prop(node, "class-code", 0);

	dev->current_state = 4;		/* unknown power state */

	if (!strcmp(type, "pci")) {
		/* a PCI-PCI bridge */
		dev->hdr_type = PCI_HEADER_TYPE_BRIDGE;
		dev->rom_base_reg = PCI_ROM_ADDRESS1;
	} else if (!strcmp(type, "cardbus")) {
		dev->hdr_type = PCI_HEADER_TYPE_CARDBUS;
	} else {
		dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
		dev->rom_base_reg = PCI_ROM_ADDRESS;
		dev->irq = NO_IRQ;
		if (node->n_intrs > 0) {
			dev->irq = node->intrs[0].line;
			pci_write_config_byte(dev, PCI_INTERRUPT_LINE,
					      dev->irq);
		}
	}

	pci_parse_of_addrs(node, dev);

	pci_device_add(dev, bus);

	/* XXX pci_scan_msi_device(dev); */

	return dev;
}

static void of_scan_pci_bridge(struct device_node *node, struct pci_dev *dev);

static void __devinit of_scan_bus(struct device_node *node,
				  struct pci_bus *bus)
{
	struct device_node *child = NULL;
	u32 *reg;
	int reglen, devfn;
	struct pci_dev *dev;

	while ((child = of_get_next_child(node, child)) != NULL) {
		reg = (u32 *) get_property(child, "reg", &reglen);
		if (reg == NULL || reglen < 20)
			continue;
		devfn = (reg[0] >> 8) & 0xff;
		/* create a new pci_dev for this device */
		dev = of_create_pci_dev(child, bus, devfn);
		if (!dev)
			continue;
		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
		    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
			of_scan_pci_bridge(child, dev);
	}

	do_bus_setup(bus);
}

static void __devinit of_scan_pci_bridge(struct device_node *node,
					 struct pci_dev *dev)
{
	struct pci_bus *bus;
	u32 *busrange, *ranges;
	int len, i, mode;
	struct resource *res;
	unsigned int flags;
	u64 size;

	/* parse bus-range property */
	busrange = (u32 *) get_property(node, "bus-range", &len);
	if (busrange == NULL || len != 8) {
		printk(KERN_ERR "Can't get bus-range for PCI-PCI bridge %s\n",
		       node->full_name);
		return;
	}
	ranges = (u32 *) get_property(node, "ranges", &len);
	if (ranges == NULL) {
		printk(KERN_ERR "Can't get ranges for PCI-PCI bridge %s\n",
		       node->full_name);
		return;
	}

	bus = pci_add_new_bus(dev->bus, dev, busrange[0]);
	if (!bus) {
		printk(KERN_ERR "Failed to create pci bus for %s\n",
		       node->full_name);
		return;
	}

	bus->primary = dev->bus->number;
	bus->subordinate = busrange[1];
	bus->bridge_ctl = 0;
	bus->sysdata = node;

	/* parse ranges property */
	/* PCI #address-cells == 3 and #size-cells == 2 always */
	res = &dev->resource[PCI_BRIDGE_RESOURCES];
	for (i = 0; i < PCI_NUM_RESOURCES - PCI_BRIDGE_RESOURCES; ++i) {
		res->flags = 0;
		bus->resource[i] = res;
		++res;
	}
	i = 1;
	for (; len >= 32; len -= 32, ranges += 8) {
		flags = pci_parse_of_flags(ranges[0]);