WebSVN - shark - Rev 587 - /shark/branches/xen/drivers/pci/probe.c

/*
* probe.c - PCI detection and setup code
*/

#include <linuxcomp.h>

#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>

//#define DEBUG

#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif

#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
#define CARDBUS_RESERVE_BUSNR 3

/* Ugh. Need to stop exporting this to modules. */
LIST_HEAD(pci_root_buses);
EXPORT_SYMBOL(pci_root_buses);

LIST_HEAD(pci_devices);

/*
* 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, unsigned long 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, 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);
if (~sz)
res->end = res->start + 0xffffffff +
(((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, PCI_ROM_ADDRESS_MASK);
if (sz) {
res->flags = (l & PCI_ROM_ADDRESS_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("Transparent bridge - %s\n", pci_name(dev));
for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++)
child->resource[i] = child->parent->resource[i];
return;
}

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 && base <= limit) {
res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
res->start = base;
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 && 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);
#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 %s\n", child->name);
return;
}
#endif
}
if (base && 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 = kmalloc(sizeof(*b), GFP_KERNEL);
if (b) {
memset(b, 0, sizeof(*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;

/*
* Allocate a new bus, and inherit stuff from the parent..
*/
child = pci_alloc_bus();

if (child) {
int i;

child->self = bridge;
child->parent = parent;
child->ops = parent->ops;
child->sysdata = parent->sysdata;
child->dev = &bridge->dev;

/*
* 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)
list_add_tail(&child->node, &parent->children);
return child;
}

static 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;

pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses);

DBG("Scanning behind PCI bridge %s, config %06x, pass %d\n",
pci_name(dev), buses & 0xffffff, pass);

if ((buses & 0xffff00) && !pcibios_assign_all_busses() && !is_cardbus) {
unsigned int cmax;
/*
* Bus already configured by firmware, process it in the first
* pass and just note the configuration.
*/
if (pass)
return max;
child = pci_alloc_child_bus(bus, dev, 0);
child->primary = buses & 0xFF;
child->secondary = (buses >> 8) & 0xFF;
child->subordinate = (buses >> 16) & 0xFF;
child->number = child->secondary;
cmax = pci_scan_child_bus(child);
if (cmax > max) max = cmax;
} else {
/*
* We need to assign a number to this bus which we always
* do in the second pass.
*/
if (!pass)
return max;

/* Clear errors */
pci_write_config_word(dev, PCI_STATUS, 0xffff);

child = pci_alloc_child_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) {
/* Now we can scan all subordinate buses... */
max = pci_scan_child_bus(child);
} else {
/*
* For CardBus bridges, we leave 4 bus numbers
* as cards with a PCI-to-PCI bridge can be
* inserted later.
*/
max += CARDBUS_RESERVE_BUSNR;
}
/*
* Set the subordinate bus number to its real value.
*/
child->subordinate = max;
pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max);
}

sprintf26(child->name, (is_cardbus ? "PCI CardBus #%02x" : "PCI Bus #%02x"), child->number);

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);
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;

dev->slot_name = dev->dev.bus_id;
sprintf26(pci_name(dev), "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus),
dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));

INIT_LIST_HEAD(&dev->pools);

pci_read_config_dword(dev, PCI_CLASS_REVISION, &class);
class >>= 8; /* upper 3 bytes */
dev->class = class;
class >>= 8;

DBG("Found %02x:%02x [%04x/%04x] %06x %02x\n", dev->bus->number,
dev->devfn, dev->vendor, dev->device, class, dev->hdr_type);

/* "Unknown power state" */
dev->current_state = 4;

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. */
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);
}

/*
* 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;

if (pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type))
return NULL;

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;

dev = kmalloc(sizeof(struct pci_dev), GFP_KERNEL);
if (!dev)
return NULL;

memset(dev, 0, sizeof(struct pci_dev));
dev->bus = bus;
dev->sysdata = bus->sysdata;
dev->dev.parent = bus->dev;
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;

/* 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;
dev->consistent_dma_mask = 0xffffffff;
if (pci_setup_device(dev) < 0) {
kfree(dev);
return NULL;
}
device_initialize(&dev->dev);
dev->dev.release = pci_release_dev;
pci_dev_get(dev);

pci_name_device(dev);

dev->dev.dma_mask = &dev->dma_mask;

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;

for (func = 0; func < 8; func++, devfn++) {
struct pci_dev *dev;

dev = pci_scan_device(bus, devfn);
if (func == 0) {
if (!dev)
break;
} else {
if (!dev)
continue;
dev->multifunction = 1;
}

/* 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);
list_add_tail(&dev->bus_list, &bus->devices);
nr++;

/*
* If this is a single function device,
* don't scan past the first function.
*/
if (!dev->multifunction)
break;
}
return nr;
}

static unsigned int __devinit pci_scan_child_bus(struct pci_bus *bus)
{
unsigned int devfn, pass, max = bus->secondary;
struct pci_dev *dev;

DBG("Scanning bus %02x\n", 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.
*/
DBG("Fixups for bus %02x\n", 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.
*/
DBG("Bus scan for %02x returning with max=%02x\n", 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_scan_bus_parented(struct device *parent, int bus, struct pci_ops *ops, void *sysdata)
{
struct pci_bus *b;

b = pci_alloc_bus();
if (!b)
return NULL;

b->dev = kmalloc(sizeof(*(b->dev)),GFP_KERNEL);
if (!b->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 */
DBG("PCI: Bus %02x already known\n", bus);
kfree(b->dev);
kfree(b);
return NULL;
}

list_add_tail(&b->node, &pci_root_buses);

memset(b->dev,0,sizeof(*(b->dev)));
b->dev->parent = parent;
sprintf26(b->dev->bus_id,"pci%04x:%02x", pci_domain_nr(b), bus);
device_register(b->dev);

b->number = b->secondary = bus;
b->resource[0] = &ioport_resource;
b->resource[1] = &iomem_resource;

b->subordinate = pci_scan_child_bus(b);

pci_bus_add_devices(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);
#endif

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(root)/shark/branches/xen/drivers/pci/probe.c - Rev 587