/*
* probe.c - PCI detection and setup code
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/cpumask.h>
#include "pci.h"
#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
#define CARDBUS_RESERVE_BUSNR 3
#define PCI_CFG_SPACE_SIZE 256
#define PCI_CFG_SPACE_EXP_SIZE 4096
/* Ugh. Need to stop exporting this to modules. */
LIST_HEAD(pci_root_buses);
EXPORT_SYMBOL(pci_root_buses);
LIST_HEAD(pci_devices);
#ifdef HAVE_PCI_LEGACY
/**
* pci_create_legacy_files - create legacy I/O port and memory files
* @b: bus to create files under
*
* Some platforms allow access to legacy I/O port and ISA memory space on
* a per-bus basis. This routine creates the files and ties them into
* their associated read, write and mmap files from pci-sysfs.c
*/
static void pci_create_legacy_files(struct pci_bus *b)
{
b->legacy_io = kzalloc(sizeof(struct bin_attribute) * 2,
GFP_ATOMIC);
if (b->legacy_io) {
b->legacy_io->attr.name = "legacy_io";
b->legacy_io->size = 0xffff;
b->legacy_io->attr.mode = S_IRUSR | S_IWUSR;
b->legacy_io->attr.owner = THIS_MODULE;
b->legacy_io->read = pci_read_legacy_io;
b->legacy_io->write = pci_write_legacy_io;
class_device_create_bin_file(&b->class_dev, b->legacy_io);
/* Allocated above after the legacy_io struct */
b->legacy_mem = b->legacy_io + 1;
b->legacy_mem->attr.name = "legacy_mem";
b->legacy_mem->size = 1024*1024;
b->legacy_mem->attr.mode = S_IRUSR | S_IWUSR;
b->legacy_mem->attr.owner = THIS_MODULE;
b->legacy_mem->mmap = pci_mmap_legacy_mem;
class_device_create_bin_file(&b->class_dev, b->legacy_mem);
}
}
void pci_remove_legacy_files(struct pci_bus *b)
{
if (b->legacy_io) {
class_device_remove_bin_file(&b->class_dev, b->legacy_io);
class_device_remove_bin_file(&b->class_dev, b->legacy_mem);
kfree(b->legacy_io); /* both are allocated here */
}
}
#else /* !HAVE_PCI_LEGACY */
static inline void pci_create_legacy_files(struct pci_bus *bus) { return; }
void pci_remove_legacy_files(struct pci_bus *bus) { return; }
#endif /* HAVE_PCI_LEGACY */
/*
* PCI Bus Class Devices
*/
static ssize_t pci_bus_show_cpuaffinity(struct class_device *class_dev,
char *buf)
{
int ret;
cpumask_t cpumask;
cpumask = pcibus_to_cpumask(to_pci_bus(class_dev));
ret = cpumask_scnprintf(buf, PAGE_SIZE, cpumask);
if (ret < PAGE_SIZE)
buf[ret++] = '\n';
return ret;
}
CLASS_DEVICE_ATTR(cpuaffinity, S_IRUGO, pci_bus_show_cpuaffinity, NULL);
/*
* PCI Bus Class
*/
static void release_pcibus_dev(struct class_device *class_dev)
{
struct pci_bus *pci_bus = to_pci_bus(class_dev);
if (pci_bus->bridge)
put_device(pci_bus->bridge);
kfree(pci_bus);
}
static struct class pcibus_class = {
.name = "pci_bus",
.release = &release_pcibus_dev,
};
static int __init pcibus_class_init(void)
{
return class_register(&pcibus_class);
}
postcore_initcall(pcibus_class_init);
/*
* Translate the low bits of the PCI base
* to the resource type
*/
static inline unsigned int pci_calc_resource_flags(unsigned int flags)
{
if (flags & PCI_BASE_ADDRESS_SPACE_IO)
return IORESOURCE_IO;
if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH)
return IORESOURCE_MEM | IORESOURCE_PREFETCH;
return IORESOURCE_MEM;
}
/*
* Find the extent of a PCI decode..
*/
static u32 pci_size(u32 base, u32 maxbase, u32 mask)
{
u32 size = mask & maxbase; /* Find the significant bits */
if (!size)
return 0;
/* Get the lowest of them to find the decode size, and
from that the extent. */
size = (size & ~(size-1)) - 1;
/* base == maxbase can be valid only if the BAR has
already been programmed with all 1s. */
if (base == maxbase && ((base | size) & mask) != mask)
return 0;
return size;
}
static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
{
unsigned int pos, reg, next;
u32 l, sz;
struct resource *res;
for(pos=0; pos<howmany; pos = next) {
next = pos+1;
res = &dev->resource[pos];
res->name = pci_name(dev);
reg = PCI_BASE_ADDRESS_0 + (pos << 2);
pci_read_config_dword(dev, reg, &l);
pci_write_config_dword(dev, reg, ~0);
pci_read_config_dword(dev, reg, &sz);
pci_write_config_dword(dev, reg, l);
if (!sz || sz == 0xffffffff)
continue;
if (l == 0xffffffff)
l = 0;
if ((l & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_MEMORY) {
sz = pci_size(l, sz, (u32)PCI_BASE_ADDRESS_MEM_MASK);
if (!sz)
continue;
res->start = l & PCI_BASE_ADDRESS_MEM_MASK;
res->flags |= l & ~PCI_BASE_ADDRESS_MEM_MASK;
} else {
sz = pci_size(l, sz, PCI_BASE_ADDRESS_IO_MASK & 0xffff);
if (!sz)
continue;
res->start = l & PCI_BASE_ADDRESS_IO_MASK;
res->flags |= l & ~PCI_BASE_ADDRESS_IO_MASK;
}
res->end = res->start + (unsigned long) sz;
res->flags |= pci_calc_resource_flags(l);
if ((l & (PCI_BASE_ADDRESS_SPACE | PCI_BASE_ADDRESS_MEM_TYPE_MASK))
== (PCI_BASE_ADDRESS_SPACE_MEMORY | PCI_BASE_ADDRESS_MEM_TYPE_64)) {
pci_read_config_dword(dev, reg+4, &l);
next++;
#if BITS_PER_LONG == 64
res->start |= ((unsigned long) l) << 32;
res->end = res->start + sz;
pci_write_config_dword(dev, reg+4, ~0);
pci_read_config_dword(dev, reg+4, &sz);
pci_write_config_dword(dev, reg+4, l);
sz = pci_size(l, sz, 0xffffffff);
if (sz) {
/* This BAR needs > 4GB? Wow. */
res->end |= (unsigned long)sz<<32;
}
#else
if (l) {
printk(KERN_ERR "PCI: Unable to handle 64-bit address for device %s\n", pci_name(dev));
res->start = 0;
res->flags = 0;
continue;
}
#endif
}
}
if (rom) {
dev->rom_base_reg = rom;
res = &dev->resource[PCI_ROM_RESOURCE];
res->name = pci_name(dev);
pci_read_config_dword(dev, rom, &l);
pci_write_config_dword(dev, rom, ~PCI_ROM_ADDRESS_ENABLE);
pci_read_config_dword(dev, rom, &sz);
pci_write_config_dword(dev, rom, l);
if (l == 0xffffffff)
l = 0;
if (sz && sz != 0xffffffff) {
sz = pci_size(l, sz, (u32)PCI_ROM_ADDRESS_MASK);
if (sz) {
res->flags = (l & IORESOURCE_ROM_ENABLE) |
IORESOURCE_MEM | IORESOURCE_PREFETCH |
IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
res->start = l & PCI_ROM_ADDRESS_MASK;
res->end = res->start + (unsigned long) sz;
}
}
}
}
void __devinit pci_read_bridge_bases(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
u8 io_base_lo, io_limit_lo;
u16 mem_base_lo, mem_limit_lo;
unsigned long base, limit;
struct resource *res;
int i;
if (!dev) /* It's a host bus, nothing to read */
return;
if (dev->transparent) {
printk(KERN_INFO "PCI: Transparent bridge - %s\n", pci_name(dev));
for(i = 3; i < PCI_BUS_NUM_RESOURCES; i++)
child->resource[i] = child->parent->resource[i - 3];
}
for(i=0; i<3; i++)
child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i];
res = child->resource[0];
pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo);
pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo);
base = (io_base_lo & PCI_IO_RANGE_MASK) << 8;
limit = (io_limit_lo & PCI_IO_RANGE_MASK) << 8;
if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) {
u16 io_base_hi, io_limit_hi;
pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi);
pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi);
base |= (io_base_hi << 16);
limit |= (io_limit_hi << 16);
}
if (base <= limit) {
res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
if (!res->start)
res->start = base;
if (!res->end)
res->end = limit + 0xfff;
}
res = child->resource[1];
pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
if (base <= limit) {
res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
res->start = base;
res->end = limit + 0xfffff;
}
res = child->resource[2];
pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
base = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
limit = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
u32 mem_base_hi, mem_limit_hi;
pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi);
pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi);
/*
* Some bridges set the base > limit by default, and some
* (broken) BIOSes do not initialize them. If we find
* this, just assume they are not being used.
*/
if (mem_base_hi <= mem_limit_hi) {
#if BITS_PER_LONG == 64
base |= ((long) mem_base_hi) << 32;
limit |= ((long) mem_limit_hi) << 32;
#else
if (mem_base_hi || mem_limit_hi) {
printk(KERN_ERR "PCI: Unable to handle 64-bit address space for bridge %s\n", pci_name(dev));
return;
}
#endif
}
}
if (base <= limit) {
res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH;
res->start = base;
res->end = limit + 0xfffff;
}
}
static struct pci_bus * __devinit pci_alloc_bus(void)
{
struct pci_bus *b;
b = kzalloc(sizeof(*b), GFP_KERNEL);
if (b) {
INIT_LIST_HEAD(&b->node);
INIT_LIST_HEAD(&b->children);
INIT_LIST_HEAD(&b->devices);
}
return b;
}
static struct pci_bus * __devinit
pci_alloc_child_bus(struct pci_bus *parent, struct pci_dev *bridge, int busnr)
{
struct pci_bus *child;
int i;
/*
* Allocate a new bus, and inherit stuff from the parent..
*/
child = pci_alloc_bus();
if (!child)
return NULL;
child->self = bridge;
child->parent = parent;
child->ops = parent->ops;
child->sysdata = parent->sysdata;
child->bus_flags = parent->bus_flags;
child->bridge = get_device(&bridge->dev);
child->class_dev.class = &pcibus_class;
sprintf(child->class_dev.class_id, "%04x:%02x", pci_domain_nr(child), busnr);
class_device_register(&child->class_dev);
class_device_create_file(&child->class_dev, &class_device_attr_cpuaffinity);
/*
* Set up the primary, secondary and subordinate
* bus numbers.
*/
child->number = child->secondary = busnr;
child->primary = parent->secondary;
child->subordinate = 0xff;
/* Set up default resource pointers and names.. */
for (i = 0; i < 4; i++) {
child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i];
child->resource[i]->name = child->name;
}
bridge->subordinate = child;
return child;
}
struct pci_bus * __devinit pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, int busnr)
{
struct pci_bus *child;
child = pci_alloc_child_bus(parent, dev, busnr);
if (child) {
spin_lock(&pci_bus_lock);
list_add_tail(&child->node, &parent->children);
spin_unlock(&pci_bus_lock);
}
return child;
}
static void pci_enable_crs(struct pci_dev *dev)
{
u16 cap, rpctl;
int rpcap = pci_find_capability(dev, PCI_CAP_ID_EXP);
if (!rpcap)
return;
pci_read_config_word(dev, rpcap + PCI_CAP_FLAGS, &cap);
if (((cap & PCI_EXP_FLAGS_TYPE) >> 4) != PCI_EXP_TYPE_ROOT_PORT)
return;
pci_read_config_word(dev, rpcap + PCI_EXP_RTCTL, &rpctl);
rpctl |= PCI_EXP_RTCTL_CRSSVE;
pci_write_config_word(dev, rpcap + PCI_EXP_RTCTL, rpctl);
}
static void __devinit pci_fixup_parent_subordinate_busnr(struct pci_bus *child, int max)
{
struct pci_bus *parent = child->parent;
/* Attempts to fix that up are really dangerous unless
we're going to re-assign all bus numbers. */
if (!pcibios_assign_all_busses())
return;
while (parent->parent && parent->subordinate < max) {
parent->subordinate = max;
pci_write_config_byte(parent->self, PCI_SUBORDINATE_BUS, max);
parent = parent->parent;
}
}
unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus);
/*
* If it's a bridge, configure it and scan the bus behind it.
* For CardBus bridges, we don't scan behind as the devices will
* be handled by the bridge driver itself.
*
* We need to process bridges in two passes -- first we scan those
* already configured by the BIOS and after we are done with all of
* them, we proceed to assigning numbers to the remaining buses in
* order to avoid overlaps between old and new bus numbers.
*/
int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int pass)
{
struct pci_bus *child;
int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS);
u32 buses, i, j = 0;
u16 bctl;
pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);
pr_debug("PCI: Scanning behind PCI bridge %s, config %06x, pass %d\n",
pci_name(dev), buses & 0xffffff, pass);
/* Disable MasterAbortMode during probing to avoid reporting
of bus errors (in some architectures) */
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl);
pci_write_config_word(dev, PCI_BRIDGE_CONTROL,
bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT);
pci_enable_crs(dev);
if ((buses & 0xffff00) && !pcibios_assign_all_busses() && !is_cardbus) {
unsigned int cmax, busnr;
/*
* Bus already configured by firmware, process it in the first
* pass and just note the configuration.
*/
if (pass)
goto out;
busnr = (buses >> 8) & 0xFF;
/*
* If we already got to this bus through a different bridge,
* ignore it. This can happen with the i450NX chipset.
*/
if (pci_find_bus(pci_domain_nr(bus), busnr)) {
printk(KERN_INFO "PCI: Bus %04x:%02x already known\n",
pci_domain_nr(bus), busnr);
goto out;
}
child = pci_add_new_bus(bus, dev, busnr);
if (!child)
goto out;
child->primary = buses & 0xFF;
child->subordinate = (buses >> 16) & 0xFF;
child->bridge_ctl = bctl;
cmax = pci_scan_child_bus(child);
if (cmax > max)
max = cmax;
if (child->subordinate > max)
max = child->subordinate;
} else {
/*
* We need to assign a number to this bus which we always
* do in the second pass.
*/
if (!pass) {
if (pcibios_assign_all_busses())
/* Temporarily disable forwarding of the
configuration cycles on all bridges in
this bus segment to avoid possible
conflicts in the second pass between two
bridges programmed with overlapping
bus ranges. */
pci_write_config_dword(dev, PCI_PRIMARY_BUS,
buses & ~0xffffff);
goto out;
}
/* Clear errors */
pci_write_config_word(dev, PCI_STATUS, 0xffff);
/* Prevent assigning a bus number that already exists.
* This can happen when a bridge is hot-plugged */
if (pci_find_bus(pci_domain_nr(bus), max+1))
goto out;
child = pci_add_new_bus(bus, dev, ++max);
buses = (buses & 0xff000000)
| ((unsigned int)(child->primary) << 0)
| ((unsigned int)(child->secondary) << 8)
| ((unsigned int)(child->subordinate) << 16);
/*
* yenta.c forces a secondary latency timer of 176.
* Copy that behaviour here.
*/
if (is_cardbus) {
buses &= ~0xff000000;
buses |= CARDBUS_LATENCY_TIMER << 24;
}
/*
* We need to blast all three values with a single write.
*/
pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses);
if (!is_cardbus) {
child->bridge_ctl = bctl | PCI_BRIDGE_CTL_NO_ISA;
/*
* Adjust subordinate busnr in parent buses.
* We do this before scanning for children because
* some devices may not be detected if the bios
* was lazy.
*/
pci_fixup_parent_subordinate_busnr(child, max);
/* Now we can scan all subordinate buses... */
max = pci_scan_child_bus(child);
/*
* now fix it up again since we have found
* the real value of max.
*/
pci_fixup_parent_subordinate_busnr(child, max);
} else {
/*
* For CardBus bridges, we leave 4 bus numbers
* as cards with a PCI-to-PCI bridge can be
* inserted later.
*/
for (i=0; i<CARDBUS_RESERVE_BUSNR; i++) {
struct pci_bus *parent = bus;
if (pci_find_bus(pci_domain_nr(bus),
max+i+1))
break;
while (parent->parent) {
if ((!pcibios_assign_all_busses()) &&
(parent->subordinate > max) &&
(parent->subordinate <= max+i)) {
j = 1;
}
parent = parent->parent;
}
if (j) {
/*
* Often, there are two cardbus bridges
* -- try to leave one valid bus number
* for each one.
*/
i /= 2;
break;
}
}
max += i;
pci_fixup_parent_subordinate_busnr(child, max);
}
/*
* Set the subordinate bus number to its real value.
*/
child->subordinate = max;
pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
}
sprintf(child->name, (is_cardbus ? "PCI CardBus #%02x" : "PCI Bus #%02x"), child->number);
while (bus->parent) {
if ((child->subordinate > bus->subordinate) ||
(child->number > bus->subordinate) ||
(child->number < bus->number) ||
(child->subordinate < bus->number)) {
printk(KERN_WARNING "PCI: Bus #%02x (-#%02x) is "
"hidden behind%s bridge #%02x (-#%02x)%s\n",
child->number, child->subordinate,
bus->self->transparent ? " transparent" : " ",
bus->number, bus->subordinate,
pcibios_assign_all_busses() ? " " :
" (try 'pci=assign-busses')");
printk(KERN_WARNING "Please report the result to "
"linux-kernel to fix this permanently\n");
}
bus = bus->parent;
}
out:
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
return max;
}
/*
* Read interrupt line and base address registers.
* The architecture-dependent code can tweak these, of course.
*/
static void pci_read_irq(struct pci_dev *dev)
{
unsigned char irq;
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
dev->pin = irq;
if (irq)
pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
dev->irq = irq;
}
/**
* pci_setup_device - fill in class and map information of a device
* @dev: the device structure to fill
*
* Initialize the device structure with information about the device's
* vendor,class,memory and IO-space addresses,IRQ lines etc.
* Called at initialisation of the PCI subsystem and by CardBus services.
* Returns 0 on success and -1 if unknown type of device (not normal, bridge
* or CardBus).
*/
static int pci_setup_device(struct pci_dev * dev)
{
u32 class;
sprintf(pci_name(dev), "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
class >>= 8; /* upper 3 bytes */
dev->class = class;
class >>= 8;
pr_debug("PCI: Found %s [%04x/%04x] %06x %02x\n", pci_name(dev),
dev->vendor, dev->device, class, dev->hdr_type);
/* "Unknown power state" */
dev->current_state = PCI_UNKNOWN;
/* Early fixups, before probing the BARs */
pci_fixup_device(pci_fixup_early, dev);
class = dev->class >> 8;
switch (dev->hdr_type) { /* header type */
case PCI_HEADER_TYPE_NORMAL: /* standard header */
if (class == PCI_CLASS_BRIDGE_PCI)
goto bad;
pci_read_irq(dev);
pci_read_bases(dev, 6, PCI_ROM_ADDRESS);
pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
pci_read_config_word(dev, PCI_SUBSYSTEM_ID, &dev->subsystem_device);
break;
case PCI_HEADER_TYPE_BRIDGE: /* bridge header */
if (class != PCI_CLASS_BRIDGE_PCI)
goto bad;
/* The PCI-to-PCI bridge spec requires that subtractive
decoding (i.e. transparent) bridge must have programming
interface code of 0x01. */
pci_read_irq(dev);
dev->transparent = ((dev->class & 0xff) == 1);
pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
break;
case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */
if (class != PCI_CLASS_BRIDGE_CARDBUS)
goto bad;
pci_read_irq(dev);
pci_read_bases(dev, 1, 0);
pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor);
pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device);
break;
default: /* unknown header */
printk(KERN_ERR "PCI: device %s has unknown header type %02x, ignoring.\n",
pci_name(dev), dev->hdr_type);
return -1;
bad:
printk(KERN_ERR "PCI: %s: class %x doesn't match header type %02x. Ignoring class.\n",
pci_name(dev), class, dev->hdr_type);
dev->class = PCI_CLASS_NOT_DEFINED;
}
/* We found a fine healthy device, go go go... */
return 0;
}
/**
* pci_release_dev - free a pci device structure when all users of it are finished.
* @dev: device that's been disconnected
*
* Will be called only by the device core when all users of this pci device are
* done.
*/
static void pci_release_dev(struct device *dev)
{
struct pci_dev *pci_dev;
pci_dev = to_pci_dev(dev);
kfree(pci_dev);
}
/**
* pci_cfg_space_size - get the configuration space size of the PCI device.
* @dev: PCI device
*
* Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices
* have 4096 bytes. Even if the device is capable, that doesn't mean we can
* access it. Maybe we don't have a way to generate extended config space
* accesses, or the device is behind a reverse Express bridge. So we try
* reading the dword at 0x100 which must either be 0 or a valid extended
* capability header.
*/
int pci_cfg_space_size(struct pci_dev *dev)
{
int pos;
u32 status;
pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
if (!pos) {
pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
if (!pos)
goto fail;
pci_read_config_dword(dev, pos + PCI_X_STATUS, &status);
if (!(status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)))
goto fail;
}
if (pci_read_config_dword(dev, 256, &status) != PCIBIOS_SUCCESSFUL)
goto fail;
if (status == 0xffffffff)
goto fail;
return PCI_CFG_SPACE_EXP_SIZE;
fail:
return PCI_CFG_SPACE_SIZE;
}
static void pci_release_bus_bridge_dev(struct device *dev)
{
kfree(dev);
}
/*
* Read the config data for a PCI device, sanity-check it
* and fill in the dev structure...
*/
static struct pci_dev * __devinit
pci_scan_device(struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
u32 l;
u8 hdr_type;
int delay = 1;
if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
return NULL;
/* some broken boards return 0 or ~0 if a slot is empty: */
if (l == 0xffffffff || l == 0x00000000 ||
l == 0x0000ffff || l == 0xffff0000)
return NULL;
/* Configuration request Retry Status */
while (l == 0xffff0001) {
msleep(delay);
delay *= 2;
if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, &l))
return NULL;
/* Card hasn't responded in 60 seconds? Must be stuck. */
if (delay > 60 * 1000) {
printk(KERN_WARNING "Device %04x:%02x:%02x.%d not "
"responding\n", pci_domain_nr(bus),
bus->number, PCI_SLOT(devfn),
PCI_FUNC(devfn));
return NULL;
}
}
if (pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type))
return NULL;
dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
if (!dev)
return NULL;
dev->bus = bus;
dev->sysdata = bus->sysdata;
dev->dev.parent = bus->bridge;
dev->dev.bus = &pci_bus_type;
dev->devfn = devfn;
dev->hdr_type = hdr_type & 0x7f;
dev->multifunction = !!(hdr_type & 0x80);
dev->vendor = l & 0xffff;
dev->device = (l >> 16) & 0xffff;
dev->cfg_size = pci_cfg_space_size(dev);
/* Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer)
set this higher, assuming the system even supports it. */
dev->dma_mask = 0xffffffff;
if (pci_setup_device(dev) < 0) {
kfree(dev);
return NULL;
}
return dev;
}
void __devinit pci_device_add(struct pci_dev *dev, struct pci_bus *bus)
{
device_initialize(&dev->dev);
dev->dev.release = pci_release_dev;
pci_dev_get(dev);
dev->dev.dma_mask = &dev->dma_mask;
dev->dev.coherent_dma_mask = 0xffffffffull;
/* Fix up broken headers */
pci_fixup_device(pci_fixup_header, dev);
/*
* Add the device to our list of discovered devices
* and the bus list for fixup functions, etc.
*/
INIT_LIST_HEAD(&dev->global_list);
spin_lock(&pci_bus_lock);
list_add_tail(&dev->bus_list, &bus->devices);
spin_unlock(&pci_bus_lock);
}
struct pci_dev * __devinit
pci_scan_single_device(struct pci_bus *bus, int devfn)
{
struct pci_dev *dev;
dev = pci_scan_device(bus, devfn);
if (!dev)
return NULL;
pci_device_add(dev, bus);
pci_scan_msi_device(dev);
return dev;
}
/**
* pci_scan_slot - scan a PCI slot on a bus for devices.
* @bus: PCI bus to scan
* @devfn: slot number to scan (must have zero function.)
*
* Scan a PCI slot on the specified PCI bus for devices, adding
* discovered devices to the @bus->devices list. New devices
* will have an empty dev->global_list head.
*/
int __devinit pci_scan_slot(struct pci_bus *bus, int devfn)
{
int func, nr = 0;
int scan_all_fns;
scan_all_fns = pcibios_scan_all_fns(bus, devfn);
for (func = 0; func < 8; func++, devfn++) {
struct pci_dev *dev;
dev = pci_scan_single_device(bus, devfn);
if (dev) {
nr++;
/*
* If this is a single function device,
* don't scan past the first function.
*/
if (!dev->multifunction) {
if (func > 0) {
dev->multifunction = 1;
} else {
break;
}
}
} else {
if (func == 0 && !scan_all_fns)
break;
}
}
return nr;
}
unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
{
unsigned int devfn, pass, max = bus->secondary;
struct pci_dev *dev;
pr_debug("PCI: Scanning bus %04x:%02x\n", pci_domain_nr(bus), bus->number);
/* Go find them, Rover! */
for (devfn = 0; devfn < 0x100; devfn += 8)
pci_scan_slot(bus, devfn);
/*
* After performing arch-dependent fixup of the bus, look behind
* all PCI-to-PCI bridges on this bus.
*/
pr_debug("PCI: Fixups for bus %04x:%02x\n", pci_domain_nr(bus), bus->number);
pcibios_fixup_bus(bus);
for (pass=0; pass < 2; pass++)
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
max = pci_scan_bridge(bus, dev, max, pass);
}
/*
* 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.
*/
pr_debug("PCI: Bus scan for %04x:%02x returning with max=%02x\n",
pci_domain_nr(bus), bus->number, max);
return max;
}
unsigned int __devinit pci_do_scan_bus(struct pci_bus *bus)
{
unsigned int max;
max = pci_scan_child_bus(bus);
/*
* Make the discovered devices available.
*/
pci_bus_add_devices(bus);
return max;
}
struct pci_bus * __devinit pci_create_bus(struct device *parent,
int bus, struct pci_ops *ops, void *sysdata)
{
int error;
struct pci_bus *b;
struct device *dev;
b = pci_alloc_bus();
if (!b)
return NULL;
dev = kmalloc(sizeof(*dev), GFP_KERNEL);
if (!dev){
kfree(b);
return NULL;
}
b->sysdata = sysdata;
b->ops = ops;
if (pci_find_bus(pci_domain_nr(b), bus)) {
/* If we already got to this bus through a different bridge, ignore it */
pr_debug("PCI: Bus %04x:%02x already known\n", pci_domain_nr(b), bus);
goto err_out;
}
spin_lock(&pci_bus_lock);
list_add_tail(&b->node, &pci_root_buses);
spin_unlock(&pci_bus_lock);
memset(dev, 0, sizeof(*dev));
dev->parent = parent;
dev->release = pci_release_bus_bridge_dev;
sprintf(dev->bus_id, "pci%04x:%02x", pci_domain_nr(b), bus);
error = device_register(dev);
if (error)
goto dev_reg_err;
b->bridge = get_device(dev);
b->class_dev.class = &pcibus_class;
sprintf(b->class_dev.class_id, "%04x:%02x", pci_domain_nr(b), bus);
error = class_device_register(&b->class_dev);
if (error)
goto class_dev_reg_err;
error = class_device_create_file(&b->class_dev, &class_device_attr_cpuaffinity);
if (error)
goto class_dev_create_file_err;
/* Create legacy_io and legacy_mem files for this bus */
pci_create_legacy_files(b);
error = sysfs_create_link(&b->class_dev.kobj, &b->bridge->kobj, "bridge");
if (error)
goto sys_create_link_err;
b->number = b->secondary = bus;
b->resource[0] = &ioport_resource;
b->resource[1] = &iomem_resource;
return b;
sys_create_link_err:
class_device_remove_file(&b->class_dev, &class_device_attr_cpuaffinity);
class_dev_create_file_err:
class_device_unregister(&b->class_dev);
class_dev_reg_err:
device_unregister(dev);
dev_reg_err:
spin_lock(&pci_bus_lock);
list_del(&b->node);
spin_unlock(&pci_bus_lock);
err_out:
kfree(dev);
kfree(b);
return NULL;
}
EXPORT_SYMBOL_GPL(pci_create_bus);
struct pci_bus * __devinit pci_scan_bus_parented(struct device *parent,
int bus, struct pci_ops *ops, void *sysdata)
{
struct pci_bus *b;
b = pci_create_bus(parent, bus, ops, sysdata);
if (b)
b->subordinate = pci_scan_child_bus(b);
return b;
}
EXPORT_SYMBOL(pci_scan_bus_parented);
#ifdef CONFIG_HOTPLUG
EXPORT_SYMBOL(pci_add_new_bus);
EXPORT_SYMBOL(pci_do_scan_bus);
EXPORT_SYMBOL(pci_scan_slot);
EXPORT_SYMBOL(pci_scan_bridge);
EXPORT_SYMBOL(pci_scan_single_device);
EXPORT_SYMBOL_GPL(pci_scan_child_bus);
#endif
