318 lines
6.4 KiB
C
318 lines
6.4 KiB
C
/*
|
|
* direct.c - Low-level direct PCI config space access
|
|
*/
|
|
|
|
#include <linux/pci.h>
|
|
#include <linux/init.h>
|
|
#include <linux/dmi.h>
|
|
#include <asm/pci_x86.h>
|
|
|
|
/*
|
|
* Functions for accessing PCI base (first 256 bytes) and extended
|
|
* (4096 bytes per PCI function) configuration space with type 1
|
|
* accesses.
|
|
*/
|
|
|
|
#define PCI_CONF1_ADDRESS(bus, devfn, reg) \
|
|
(0x80000000 | ((reg & 0xF00) << 16) | (bus << 16) \
|
|
| (devfn << 8) | (reg & 0xFC))
|
|
|
|
static int pci_conf1_read(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 *value)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if ((bus > 255) || (devfn > 255) || (reg > 4095)) {
|
|
*value = -1;
|
|
return -EINVAL;
|
|
}
|
|
|
|
spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
outl(PCI_CONF1_ADDRESS(bus, devfn, reg), 0xCF8);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
*value = inb(0xCFC + (reg & 3));
|
|
break;
|
|
case 2:
|
|
*value = inw(0xCFC + (reg & 2));
|
|
break;
|
|
case 4:
|
|
*value = inl(0xCFC);
|
|
break;
|
|
}
|
|
|
|
spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pci_conf1_write(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 value)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if ((bus > 255) || (devfn > 255) || (reg > 4095))
|
|
return -EINVAL;
|
|
|
|
spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
outl(PCI_CONF1_ADDRESS(bus, devfn, reg), 0xCF8);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
outb((u8)value, 0xCFC + (reg & 3));
|
|
break;
|
|
case 2:
|
|
outw((u16)value, 0xCFC + (reg & 2));
|
|
break;
|
|
case 4:
|
|
outl((u32)value, 0xCFC);
|
|
break;
|
|
}
|
|
|
|
spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#undef PCI_CONF1_ADDRESS
|
|
|
|
struct pci_raw_ops pci_direct_conf1 = {
|
|
.read = pci_conf1_read,
|
|
.write = pci_conf1_write,
|
|
};
|
|
|
|
|
|
/*
|
|
* Functions for accessing PCI configuration space with type 2 accesses
|
|
*/
|
|
|
|
#define PCI_CONF2_ADDRESS(dev, reg) (u16)(0xC000 | (dev << 8) | reg)
|
|
|
|
static int pci_conf2_read(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 *value)
|
|
{
|
|
unsigned long flags;
|
|
int dev, fn;
|
|
|
|
if ((bus > 255) || (devfn > 255) || (reg > 255)) {
|
|
*value = -1;
|
|
return -EINVAL;
|
|
}
|
|
|
|
dev = PCI_SLOT(devfn);
|
|
fn = PCI_FUNC(devfn);
|
|
|
|
if (dev & 0x10)
|
|
return PCIBIOS_DEVICE_NOT_FOUND;
|
|
|
|
spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
outb((u8)(0xF0 | (fn << 1)), 0xCF8);
|
|
outb((u8)bus, 0xCFA);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
*value = inb(PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
case 2:
|
|
*value = inw(PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
case 4:
|
|
*value = inl(PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
}
|
|
|
|
outb(0, 0xCF8);
|
|
|
|
spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pci_conf2_write(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 value)
|
|
{
|
|
unsigned long flags;
|
|
int dev, fn;
|
|
|
|
if ((bus > 255) || (devfn > 255) || (reg > 255))
|
|
return -EINVAL;
|
|
|
|
dev = PCI_SLOT(devfn);
|
|
fn = PCI_FUNC(devfn);
|
|
|
|
if (dev & 0x10)
|
|
return PCIBIOS_DEVICE_NOT_FOUND;
|
|
|
|
spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
outb((u8)(0xF0 | (fn << 1)), 0xCF8);
|
|
outb((u8)bus, 0xCFA);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
outb((u8)value, PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
case 2:
|
|
outw((u16)value, PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
case 4:
|
|
outl((u32)value, PCI_CONF2_ADDRESS(dev, reg));
|
|
break;
|
|
}
|
|
|
|
outb(0, 0xCF8);
|
|
|
|
spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#undef PCI_CONF2_ADDRESS
|
|
|
|
struct pci_raw_ops pci_direct_conf2 = {
|
|
.read = pci_conf2_read,
|
|
.write = pci_conf2_write,
|
|
};
|
|
|
|
|
|
/*
|
|
* Before we decide to use direct hardware access mechanisms, we try to do some
|
|
* trivial checks to ensure it at least _seems_ to be working -- we just test
|
|
* whether bus 00 contains a host bridge (this is similar to checking
|
|
* techniques used in XFree86, but ours should be more reliable since we
|
|
* attempt to make use of direct access hints provided by the PCI BIOS).
|
|
*
|
|
* This should be close to trivial, but it isn't, because there are buggy
|
|
* chipsets (yes, you guessed it, by Intel and Compaq) that have no class ID.
|
|
*/
|
|
static int __init pci_sanity_check(struct pci_raw_ops *o)
|
|
{
|
|
u32 x = 0;
|
|
int devfn;
|
|
|
|
if (pci_probe & PCI_NO_CHECKS)
|
|
return 1;
|
|
/* Assume Type 1 works for newer systems.
|
|
This handles machines that don't have anything on PCI Bus 0. */
|
|
if (dmi_get_year(DMI_BIOS_DATE) >= 2001)
|
|
return 1;
|
|
|
|
for (devfn = 0; devfn < 0x100; devfn++) {
|
|
if (o->read(0, 0, devfn, PCI_CLASS_DEVICE, 2, &x))
|
|
continue;
|
|
if (x == PCI_CLASS_BRIDGE_HOST || x == PCI_CLASS_DISPLAY_VGA)
|
|
return 1;
|
|
|
|
if (o->read(0, 0, devfn, PCI_VENDOR_ID, 2, &x))
|
|
continue;
|
|
if (x == PCI_VENDOR_ID_INTEL || x == PCI_VENDOR_ID_COMPAQ)
|
|
return 1;
|
|
}
|
|
|
|
DBG(KERN_WARNING "PCI: Sanity check failed\n");
|
|
return 0;
|
|
}
|
|
|
|
static int __init pci_check_type1(void)
|
|
{
|
|
unsigned long flags;
|
|
unsigned int tmp;
|
|
int works = 0;
|
|
|
|
local_irq_save(flags);
|
|
|
|
outb(0x01, 0xCFB);
|
|
tmp = inl(0xCF8);
|
|
outl(0x80000000, 0xCF8);
|
|
if (inl(0xCF8) == 0x80000000 && pci_sanity_check(&pci_direct_conf1)) {
|
|
works = 1;
|
|
}
|
|
outl(tmp, 0xCF8);
|
|
local_irq_restore(flags);
|
|
|
|
return works;
|
|
}
|
|
|
|
static int __init pci_check_type2(void)
|
|
{
|
|
unsigned long flags;
|
|
int works = 0;
|
|
|
|
local_irq_save(flags);
|
|
|
|
outb(0x00, 0xCFB);
|
|
outb(0x00, 0xCF8);
|
|
outb(0x00, 0xCFA);
|
|
if (inb(0xCF8) == 0x00 && inb(0xCFA) == 0x00 &&
|
|
pci_sanity_check(&pci_direct_conf2)) {
|
|
works = 1;
|
|
}
|
|
|
|
local_irq_restore(flags);
|
|
|
|
return works;
|
|
}
|
|
|
|
void __init pci_direct_init(int type)
|
|
{
|
|
if (type == 0)
|
|
return;
|
|
printk(KERN_INFO "PCI: Using configuration type %d for base access\n",
|
|
type);
|
|
if (type == 1) {
|
|
raw_pci_ops = &pci_direct_conf1;
|
|
if (raw_pci_ext_ops)
|
|
return;
|
|
if (!(pci_probe & PCI_HAS_IO_ECS))
|
|
return;
|
|
printk(KERN_INFO "PCI: Using configuration type 1 "
|
|
"for extended access\n");
|
|
raw_pci_ext_ops = &pci_direct_conf1;
|
|
return;
|
|
}
|
|
raw_pci_ops = &pci_direct_conf2;
|
|
}
|
|
|
|
int __init pci_direct_probe(void)
|
|
{
|
|
struct resource *region, *region2;
|
|
|
|
if ((pci_probe & PCI_PROBE_CONF1) == 0)
|
|
goto type2;
|
|
region = request_region(0xCF8, 8, "PCI conf1");
|
|
if (!region)
|
|
goto type2;
|
|
|
|
if (pci_check_type1()) {
|
|
raw_pci_ops = &pci_direct_conf1;
|
|
port_cf9_safe = true;
|
|
return 1;
|
|
}
|
|
release_resource(region);
|
|
|
|
type2:
|
|
if ((pci_probe & PCI_PROBE_CONF2) == 0)
|
|
return 0;
|
|
region = request_region(0xCF8, 4, "PCI conf2");
|
|
if (!region)
|
|
return 0;
|
|
region2 = request_region(0xC000, 0x1000, "PCI conf2");
|
|
if (!region2)
|
|
goto fail2;
|
|
|
|
if (pci_check_type2()) {
|
|
raw_pci_ops = &pci_direct_conf2;
|
|
port_cf9_safe = true;
|
|
return 2;
|
|
}
|
|
|
|
release_resource(region2);
|
|
fail2:
|
|
release_resource(region);
|
|
return 0;
|
|
}
|