kernel-ark/arch/i386/pci/common.c
Bernhard Kaindl 8c4b2cf9af [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>
2006-03-23 14:35:14 -08:00

294 lines
6.7 KiB
C

/*
* Low-Level PCI Support for PC
*
* (c) 1999--2000 Martin Mares <mj@ucw.cz>
*/
#include <linux/sched.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/dmi.h>
#include <asm/acpi.h>
#include <asm/segment.h>
#include <asm/io.h>
#include <asm/smp.h>
#include "pci.h"
#ifdef CONFIG_PCI_BIOS
extern void pcibios_sort(void);
#endif
unsigned int pci_probe = PCI_PROBE_BIOS | PCI_PROBE_CONF1 | PCI_PROBE_CONF2 |
PCI_PROBE_MMCONF;
int pci_routeirq;
int pcibios_last_bus = -1;
unsigned long pirq_table_addr;
struct pci_bus *pci_root_bus;
struct pci_raw_ops *raw_pci_ops;
static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
{
return raw_pci_ops->read(0, bus->number, devfn, where, size, value);
}
static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
{
return raw_pci_ops->write(0, bus->number, devfn, where, size, value);
}
struct pci_ops pci_root_ops = {
.read = pci_read,
.write = pci_write,
};
/*
* legacy, numa, and acpi all want to call pcibios_scan_root
* from their initcalls. This flag prevents that.
*/
int pcibios_scanned;
/*
* This interrupt-safe spinlock protects all accesses to PCI
* configuration space.
*/
DEFINE_SPINLOCK(pci_config_lock);
/*
* Several buggy motherboards address only 16 devices and mirror
* them to next 16 IDs. We try to detect this `feature' on all
* primary buses (those containing host bridges as they are
* expected to be unique) and remove the ghost devices.
*/
static void __devinit pcibios_fixup_ghosts(struct pci_bus *b)
{
struct list_head *ln, *mn;
struct pci_dev *d, *e;
int mirror = PCI_DEVFN(16,0);
int seen_host_bridge = 0;
int i;
DBG("PCI: Scanning for ghost devices on bus %d\n", b->number);
list_for_each(ln, &b->devices) {
d = pci_dev_b(ln);
if ((d->class >> 8) == PCI_CLASS_BRIDGE_HOST)
seen_host_bridge++;
for (mn=ln->next; mn != &b->devices; mn=mn->next) {
e = pci_dev_b(mn);
if (e->devfn != d->devfn + mirror ||
e->vendor != d->vendor ||
e->device != d->device ||
e->class != d->class)
continue;
for(i=0; i<PCI_NUM_RESOURCES; i++)
if (e->resource[i].start != d->resource[i].start ||
e->resource[i].end != d->resource[i].end ||
e->resource[i].flags != d->resource[i].flags)
continue;
break;
}
if (mn == &b->devices)
return;
}
if (!seen_host_bridge)
return;
printk(KERN_WARNING "PCI: Ignoring ghost devices on bus %02x\n", b->number);
ln = &b->devices;
while (ln->next != &b->devices) {
d = pci_dev_b(ln->next);
if (d->devfn >= mirror) {
list_del(&d->global_list);
list_del(&d->bus_list);
kfree(d);
} else
ln = ln->next;
}
}
/*
* Called after each bus is probed, but before its children
* are examined.
*/
void __devinit pcibios_fixup_bus(struct pci_bus *b)
{
pcibios_fixup_ghosts(b);
pci_read_bridge_bases(b);
}
/*
* Enable renumbering of PCI bus# ranges to reach all PCI busses (Cardbus)
*/
#ifdef __i386__
static int __devinit assign_all_busses(struct dmi_system_id *d)
{
pci_probe |= PCI_ASSIGN_ALL_BUSSES;
printk(KERN_INFO "%s detected: enabling PCI bus# renumbering"
" (pci=assign-busses)\n", d->ident);
return 0;
}
#endif
/*
* Laptops which need pci=assign-busses to see Cardbus cards
*/
static struct dmi_system_id __devinitdata pciprobe_dmi_table[] = {
#ifdef __i386__
{
.callback = assign_all_busses,
.ident = "Samsung X20 Laptop",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Samsung Electronics"),
DMI_MATCH(DMI_PRODUCT_NAME, "SX20S"),
},
},
#endif /* __i386__ */
{}
};
struct pci_bus * __devinit pcibios_scan_root(int busnum)
{
struct pci_bus *bus = NULL;
dmi_check_system(pciprobe_dmi_table);
while ((bus = pci_find_next_bus(bus)) != NULL) {
if (bus->number == busnum) {
/* Already scanned */
return bus;
}
}
printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
return pci_scan_bus_parented(NULL, busnum, &pci_root_ops, NULL);
}
extern u8 pci_cache_line_size;
static int __init pcibios_init(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
if (!raw_pci_ops) {
printk(KERN_WARNING "PCI: System does not support PCI\n");
return 0;
}
/*
* Assume PCI cacheline size of 32 bytes for all x86s except K7/K8
* and P4. It's also good for 386/486s (which actually have 16)
* as quite a few PCI devices do not support smaller values.
*/
pci_cache_line_size = 32 >> 2;
if (c->x86 >= 6 && c->x86_vendor == X86_VENDOR_AMD)
pci_cache_line_size = 64 >> 2; /* K7 & K8 */
else if (c->x86 > 6 && c->x86_vendor == X86_VENDOR_INTEL)
pci_cache_line_size = 128 >> 2; /* P4 */
pcibios_resource_survey();
#ifdef CONFIG_PCI_BIOS
if ((pci_probe & PCI_BIOS_SORT) && !(pci_probe & PCI_NO_SORT))
pcibios_sort();
#endif
return 0;
}
subsys_initcall(pcibios_init);
char * __devinit pcibios_setup(char *str)
{
if (!strcmp(str, "off")) {
pci_probe = 0;
return NULL;
}
#ifdef CONFIG_PCI_BIOS
else if (!strcmp(str, "bios")) {
pci_probe = PCI_PROBE_BIOS;
return NULL;
} else if (!strcmp(str, "nobios")) {
pci_probe &= ~PCI_PROBE_BIOS;
return NULL;
} else if (!strcmp(str, "nosort")) {
pci_probe |= PCI_NO_SORT;
return NULL;
} else if (!strcmp(str, "biosirq")) {
pci_probe |= PCI_BIOS_IRQ_SCAN;
return NULL;
} else if (!strncmp(str, "pirqaddr=", 9)) {
pirq_table_addr = simple_strtoul(str+9, NULL, 0);
return NULL;
}
#endif
#ifdef CONFIG_PCI_DIRECT
else if (!strcmp(str, "conf1")) {
pci_probe = PCI_PROBE_CONF1 | PCI_NO_CHECKS;
return NULL;
}
else if (!strcmp(str, "conf2")) {
pci_probe = PCI_PROBE_CONF2 | PCI_NO_CHECKS;
return NULL;
}
#endif
#ifdef CONFIG_PCI_MMCONFIG
else if (!strcmp(str, "nommconf")) {
pci_probe &= ~PCI_PROBE_MMCONF;
return NULL;
}
#endif
else if (!strcmp(str, "noacpi")) {
acpi_noirq_set();
return NULL;
}
#ifndef CONFIG_X86_VISWS
else if (!strcmp(str, "usepirqmask")) {
pci_probe |= PCI_USE_PIRQ_MASK;
return NULL;
} else if (!strncmp(str, "irqmask=", 8)) {
pcibios_irq_mask = simple_strtol(str+8, NULL, 0);
return NULL;
} else if (!strncmp(str, "lastbus=", 8)) {
pcibios_last_bus = simple_strtol(str+8, NULL, 0);
return NULL;
}
#endif
else if (!strcmp(str, "rom")) {
pci_probe |= PCI_ASSIGN_ROMS;
return NULL;
} else if (!strcmp(str, "assign-busses")) {
pci_probe |= PCI_ASSIGN_ALL_BUSSES;
return NULL;
} else if (!strcmp(str, "routeirq")) {
pci_routeirq = 1;
return NULL;
}
return str;
}
unsigned int pcibios_assign_all_busses(void)
{
return (pci_probe & PCI_ASSIGN_ALL_BUSSES) ? 1 : 0;
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
int err;
if ((err = pcibios_enable_resources(dev, mask)) < 0)
return err;
return pcibios_enable_irq(dev);
}
void pcibios_disable_device (struct pci_dev *dev)
{
if (pcibios_disable_irq)
pcibios_disable_irq(dev);
}