1
linux/drivers/pci/probe.c

1234 lines
33 KiB
C
Raw Normal View History

/*
* 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 u64 pci_size64(u64 base, u64 maxbase, u64 mask)
{
u64 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 inline int is_64bit_memory(u32 mask)
{
if ((mask & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
(PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64))
return 1;
return 0;
}
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) {
u64 l64;
u64 sz64;
u32 raw_sz;
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;
raw_sz = sz;
if ((l & PCI_BASE_ADDRESS_SPACE) ==
PCI_BASE_ADDRESS_SPACE_MEMORY) {
sz = pci_size(l, sz, (u32)PCI_BASE_ADDRESS_MEM_MASK);
/*
* For 64bit prefetchable memory sz could be 0, if the
* real size is bigger than 4G, so we need to check
* szhi for that.
*/
if (!is_64bit_memory(l) && !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 (is_64bit_memory(l)) {
u32 szhi, lhi;
pci_read_config_dword(dev, reg+4, &lhi);
pci_write_config_dword(dev, reg+4, ~0);
pci_read_config_dword(dev, reg+4, &szhi);
pci_write_config_dword(dev, reg+4, lhi);
sz64 = ((u64)szhi << 32) | raw_sz;
l64 = ((u64)lhi << 32) | l;
sz64 = pci_size64(l64, sz64, PCI_BASE_ADDRESS_MEM_MASK);
next++;
#if BITS_PER_LONG == 64
if (!sz64) {
res->start = 0;
res->end = 0;
res->flags = 0;
continue;
}
res->start = l64 & PCI_BASE_ADDRESS_MEM_MASK;
res->end = res->start + sz64;
#else
if (sz64 > 0x100000000ULL) {
printk(KERN_ERR "PCI: Unable to handle 64-bit "
"BAR for device %s\n", pci_name(dev));
res->start = 0;
res->flags = 0;
} else if (lhi) {
/* 64-bit wide address, treat as disabled */
pci_write_config_dword(dev, reg,
l & ~(u32)PCI_BASE_ADDRESS_MEM_MASK);
pci_write_config_dword(dev, reg+4, 0);
res->start = 0;
res->end = sz;
}
#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;
int retval;
/*
* 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);
retval = class_device_register(&child->class_dev);
if (retval)
goto error_register;
retval = class_device_create_file(&child->class_dev,
&class_device_attr_cpuaffinity);
if (retval)
goto error_file_create;
/*
* 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;
error_file_create:
class_device_unregister(&child->class_dev);
error_register:
kfree(child);
return NULL;
}
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) {
down_write(&pci_bus_sem);
list_add_tail(&child->node, &parent->children);
up_write(&pci_bus_sem);
}
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)
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
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);
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
goto out;
}
child = pci_add_new_bus(bus, dev, busnr);
if (!child)
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
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);
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
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))
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
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)) {
[PATCH] PCI: PCI/Cardbus cards hidden, needs pci=assign-busses to fix "In some cases, especially on modern laptops with a lot of PCI and cardbus bridges, we're unable to assign correct secondary/subordinate bus numbers to all cardbus bridges due to BIOS limitations unless we are using "pci=assign-busses" boot option." -- Ivan Kokshaysky (from a patch comment) Without it, Cardbus cards inserted are never seen by PCI because the parent PCI-PCI Bridge of the Cardbus bridge will not pass and translate Type 1 PCI configuration cycles correctly and the system will fail to find and initialise the PCI devices in the system. Reference: PCI-PCI Bridges: PCI Configuration Cycles and PCI Bus Numbering: http://www.science.unitn.it/~fiorella/guidelinux/tlk/node72.html The reason for this is that: ``All PCI busses located behind a PCI-PCI bridge must reside between the secondary bus number and the subordinate bus number (inclusive).'' "pci=assign-busses" makes pcibios_assign_all_busses return 1 and this turns on PCI renumbering during PCI probing. Alan suggested to use DMI automatically set assign-busses on problem systems. The only question for me was where to put it. I put it directly before scanning PCI bus into pcibios_scan_root() because it's called from legacy, acpi and numa and so it can be one place for all systems and configurations which may need it. AMD64 Laptops are also affected and fixed by assign-busses, and the code is also incuded from arch/x86_64/pci/ that place will also work for x86_64 kernels, I only ifdef'-ed the x86-only Laptop in this example. Affected and known or assumed to be fixed with it are (found by googling): * ASUS Z71V and L3s * Samsung X20 * Compaq R3140us and all Compaq R3000 series laptops with TI1620 Controller, also Compaq R4000 series (from a kernel.org bugreport) * HP zv5000z (AMD64 3700+, known that fixup_parent_subordinate_busnr fixes it) * HP zv5200z * IBM ThinkPad 240 * An IBM ThinkPad (1.8 GHz Pentium M) debugged by Pavel Machek gives the correspondig message which detects the possible problem. * MSI S260 / Medion SIM 2100 MD 95600 The patch also expands the "try pci=assign-busses" warning so testers will help us to update the DMI table. Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-18 02:36:55 -07:00
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')");
[PATCH] PCI: PCI/Cardbus cards hidden, needs pci=assign-busses to fix "In some cases, especially on modern laptops with a lot of PCI and cardbus bridges, we're unable to assign correct secondary/subordinate bus numbers to all cardbus bridges due to BIOS limitations unless we are using "pci=assign-busses" boot option." -- Ivan Kokshaysky (from a patch comment) Without it, Cardbus cards inserted are never seen by PCI because the parent PCI-PCI Bridge of the Cardbus bridge will not pass and translate Type 1 PCI configuration cycles correctly and the system will fail to find and initialise the PCI devices in the system. Reference: PCI-PCI Bridges: PCI Configuration Cycles and PCI Bus Numbering: http://www.science.unitn.it/~fiorella/guidelinux/tlk/node72.html The reason for this is that: ``All PCI busses located behind a PCI-PCI bridge must reside between the secondary bus number and the subordinate bus number (inclusive).'' "pci=assign-busses" makes pcibios_assign_all_busses return 1 and this turns on PCI renumbering during PCI probing. Alan suggested to use DMI automatically set assign-busses on problem systems. The only question for me was where to put it. I put it directly before scanning PCI bus into pcibios_scan_root() because it's called from legacy, acpi and numa and so it can be one place for all systems and configurations which may need it. AMD64 Laptops are also affected and fixed by assign-busses, and the code is also incuded from arch/x86_64/pci/ that place will also work for x86_64 kernels, I only ifdef'-ed the x86-only Laptop in this example. Affected and known or assumed to be fixed with it are (found by googling): * ASUS Z71V and L3s * Samsung X20 * Compaq R3140us and all Compaq R3000 series laptops with TI1620 Controller, also Compaq R4000 series (from a kernel.org bugreport) * HP zv5000z (AMD64 3700+, known that fixup_parent_subordinate_busnr fixes it) * HP zv5200z * IBM ThinkPad 240 * An IBM ThinkPad (1.8 GHz Pentium M) debugged by Pavel Machek gives the correspondig message which detects the possible problem. * MSI S260 / Medion SIM 2100 MD 95600 The patch also expands the "try pci=assign-busses" warning so testers will help us to update the DMI table. Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-18 02:36:55 -07:00
printk(KERN_WARNING "Please report the result to "
"linux-kernel to fix this permanently\n");
}
bus = bus->parent;
}
[PATCH] PCI: Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. > On Mon, Feb 13, 2006 at 05:13:21PM -0800, David S. Miller wrote: > > > > In drivers/pci/probe.c:pci_scan_bridge(), if this is not the first > > pass (pass != 0) we don't restore the PCI_BRIDGE_CONTROL_REGISTER and > > thus leave PCI_BRIDGE_CTL_MASTER_ABORT off: > > > > int __devinit pci_scan_bridge(struct pci_bus *bus, struct pci_dev * dev, int max, int 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); > > ... > > 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) > > return max; > > ... > > } > > > > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); > > ... > > > > This doesn't seem intentional. Agreed, looks like an accident. The patch [1] originally came from Kip Walker (Broadcom back then) between 2.6.0-test3 and 2.6.0-test4. As I recall it was supposed to fix an issue with with PCI aborts being signalled by the PCI bridge of the Broadcom BCM1250 family of SOCs when probing behind pci_scan_bridge. It is undeseriable to disable PCI_BRIDGE_CTL_MASTER_ABORT in pci_{read,write)_config_* and the behaviour wasn't considered a bug in need of a workaround, so this was put in probe.c. I don't have an affected system at hand, so can't really test but I propose something like the below patch. [1] http://www.linux-mips.org/git?p=linux.git;a=commit;h=599457e0cb702a31a3247ea6a5d9c6c99c4cf195 [PCI] Avoid leaving MASTER_ABORT disabled permanently when returning from pci_scan_bridge. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-02-14 09:23:57 -07:00
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;
}
#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)
/**
* 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);
/*
* Do the ugly legacy mode stuff here rather than broken chip
* quirk code. Legacy mode ATA controllers have fixed
* addresses. These are not always echoed in BAR0-3, and
* BAR0-3 in a few cases contain junk!
*/
if (class == PCI_CLASS_STORAGE_IDE) {
u8 progif;
pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
if ((progif & 1) == 0) {
dev->resource[0].start = 0x1F0;
dev->resource[0].end = 0x1F7;
dev->resource[0].flags = LEGACY_IO_RESOURCE;
dev->resource[1].start = 0x3F6;
dev->resource[1].end = 0x3F6;
dev->resource[1].flags = LEGACY_IO_RESOURCE;
}
if ((progif & 4) == 0) {
dev->resource[2].start = 0x170;
dev->resource[2].end = 0x177;
dev->resource[2].flags = LEGACY_IO_RESOURCE;
dev->resource[3].start = 0x376;
dev->resource[3].end = 0x376;
dev->resource[3].flags = LEGACY_IO_RESOURCE;
}
}
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);
dev->error_state = pci_channel_io_normal;
/* 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);
set_dev_node(&dev->dev, pcibus_to_node(bus));
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);
down_write(&pci_bus_sem);
list_add_tail(&dev->bus_list, &bus->devices);
up_write(&pci_bus_sem);
}
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);
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;
}
down_write(&pci_bus_sem);
list_add_tail(&b->node, &pci_root_buses);
up_write(&pci_bus_sem);
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:
down_write(&pci_bus_sem);
list_del(&b->node);
up_write(&pci_bus_sem);
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
PCI: optionally sort device lists breadth-first Problem: New Dell PowerEdge servers have 2 embedded ethernet ports, which are labeled NIC1 and NIC2 on the chassis, in the BIOS setup screens, and in the printed documentation. Assuming no other add-in ethernet ports in the system, Linux 2.4 kernels name these eth0 and eth1 respectively. Many people have come to expect this naming. Linux 2.6 kernels name these eth1 and eth0 respectively (backwards from expectations). I also have reports that various Sun and HP servers have similar behavior. Root cause: Linux 2.4 kernels walk the pci_devices list, which happens to be sorted in breadth-first order (or pcbios_find_device order on i386, which most often is breadth-first also). 2.6 kernels have both the pci_devices list and the pci_bus_type.klist_devices list, the latter is what is walked at driver load time to match the pci_id tables; this klist happens to be in depth-first order. On systems where, for physical routing reasons, NIC1 appears on a lower bus number than NIC2, but NIC2's bridge is discovered first in the depth-first ordering, NIC2 will be discovered before NIC1. If the list were sorted breadth-first, NIC1 would be discovered before NIC2. A PowerEdge 1955 system has the following topology which easily exhibits the difference between depth-first and breadth-first device lists. -[0000:00]-+-00.0 Intel Corporation 5000P Chipset Memory Controller Hub +-02.0-[0000:03-08]--+-00.0-[0000:04-07]--+-00.0-[0000:05-06]----00.0-[0000:06]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC2, 2.4 kernel name eth1, 2.6 kernel name eth0) +-1c.0-[0000:01-02]----00.0-[0000:02]----00.0 Broadcom Corporation NetXtreme II BCM5708S Gigabit Ethernet (labeled NIC1, 2.4 kernel name eth0, 2.6 kernel name eth1) Other factors, such as device driver load order and the presence of PCI slots at various points in the bus hierarchy further complicate this problem; I'm not trying to solve those here, just restore the device order, and thus basic behavior, that 2.4 kernels had. Solution: The solution can come in multiple steps. Suggested fix #1: kernel Patch below optionally sorts the two device lists into breadth-first ordering to maintain compatibility with 2.4 kernels. It adds two new command line options: pci=bfsort pci=nobfsort to force the sort order, or not, as you wish. It also adds DMI checks for the specific Dell systems which exhibit "backwards" ordering, to make them "right". Suggested fix #2: udev rules from userland Many people also have the expectation that embedded NICs are always discovered before add-in NICs (which this patch does not try to do). Using the PCI IRQ Routing Table provided by system BIOS, it's easy to determine which PCI devices are embedded, or if add-in, which PCI slot they're in. I'm working on a tool that would allow udev to name ethernet devices in ascending embedded, slot 1 .. slot N order, subsort by PCI bus/dev/fn breadth-first. It'll be possible to use it independent of udev as well for those distributions that don't use udev in their installers. Suggested fix #3: system board routing rules One can constrain the system board layout to put NIC1 ahead of NIC2 regardless of breadth-first or depth-first discovery order. This adds a significant level of complexity to board routing, and may not be possible in all instances (witness the above systems from several major manufacturers). I don't want to encourage this particular train of thought too far, at the expense of not doing #1 or #2 above. Feedback appreciated. Patch tested on a Dell PowerEdge 1955 blade with 2.6.18. You'll also note I took some liberty and temporarily break the klist abstraction to simplify and speed up the sort algorithm. I think that's both safe and appropriate in this instance. Signed-off-by: Matt Domsch <Matt_Domsch@dell.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-29 13:23:23 -07:00
static int __init pci_sort_bf_cmp(const struct pci_dev *a, const struct pci_dev *b)
{
if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1;
else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1;
if (a->bus->number < b->bus->number) return -1;
else if (a->bus->number > b->bus->number) return 1;
if (a->devfn < b->devfn) return -1;
else if (a->devfn > b->devfn) return 1;
return 0;
}
/*
* Yes, this forcably breaks the klist abstraction temporarily. It
* just wants to sort the klist, not change reference counts and
* take/drop locks rapidly in the process. It does all this while
* holding the lock for the list, so objects can't otherwise be
* added/removed while we're swizzling.
*/
static void __init pci_insertion_sort_klist(struct pci_dev *a, struct list_head *list)
{
struct list_head *pos;
struct klist_node *n;
struct device *dev;
struct pci_dev *b;
list_for_each(pos, list) {
n = container_of(pos, struct klist_node, n_node);
dev = container_of(n, struct device, knode_bus);
b = to_pci_dev(dev);
if (pci_sort_bf_cmp(a, b) <= 0) {
list_move_tail(&a->dev.knode_bus.n_node, &b->dev.knode_bus.n_node);
return;
}
}
list_move_tail(&a->dev.knode_bus.n_node, list);
}
static void __init pci_sort_breadthfirst_klist(void)
{
LIST_HEAD(sorted_devices);
struct list_head *pos, *tmp;
struct klist_node *n;
struct device *dev;
struct pci_dev *pdev;
spin_lock(&pci_bus_type.klist_devices.k_lock);
list_for_each_safe(pos, tmp, &pci_bus_type.klist_devices.k_list) {
n = container_of(pos, struct klist_node, n_node);
dev = container_of(n, struct device, knode_bus);
pdev = to_pci_dev(dev);
pci_insertion_sort_klist(pdev, &sorted_devices);
}
list_splice(&sorted_devices, &pci_bus_type.klist_devices.k_list);
spin_unlock(&pci_bus_type.klist_devices.k_lock);
}
static void __init pci_insertion_sort_devices(struct pci_dev *a, struct list_head *list)
{
struct pci_dev *b;
list_for_each_entry(b, list, global_list) {
if (pci_sort_bf_cmp(a, b) <= 0) {
list_move_tail(&a->global_list, &b->global_list);
return;
}
}
list_move_tail(&a->global_list, list);
}
static void __init pci_sort_breadthfirst_devices(void)
{
LIST_HEAD(sorted_devices);
struct pci_dev *dev, *tmp;
down_write(&pci_bus_sem);
list_for_each_entry_safe(dev, tmp, &pci_devices, global_list) {
pci_insertion_sort_devices(dev, &sorted_devices);
}
list_splice(&sorted_devices, &pci_devices);
up_write(&pci_bus_sem);
}
void __init pci_sort_breadthfirst(void)
{
pci_sort_breadthfirst_devices();
pci_sort_breadthfirst_klist();
}