454 lines
11 KiB
C
454 lines
11 KiB
C
/*
|
|
* BIOS32 and PCI BIOS handling.
|
|
*/
|
|
|
|
#include <linux/pci.h>
|
|
#include <linux/init.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
#include <linux/uaccess.h>
|
|
#include <asm/pci_x86.h>
|
|
#include <asm/pci-functions.h>
|
|
#include <asm/cacheflush.h>
|
|
|
|
/* BIOS32 signature: "_32_" */
|
|
#define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24))
|
|
|
|
/* PCI signature: "PCI " */
|
|
#define PCI_SIGNATURE (('P' << 0) + ('C' << 8) + ('I' << 16) + (' ' << 24))
|
|
|
|
/* PCI service signature: "$PCI" */
|
|
#define PCI_SERVICE (('$' << 0) + ('P' << 8) + ('C' << 16) + ('I' << 24))
|
|
|
|
/* PCI BIOS hardware mechanism flags */
|
|
#define PCIBIOS_HW_TYPE1 0x01
|
|
#define PCIBIOS_HW_TYPE2 0x02
|
|
#define PCIBIOS_HW_TYPE1_SPEC 0x10
|
|
#define PCIBIOS_HW_TYPE2_SPEC 0x20
|
|
|
|
int pcibios_enabled;
|
|
|
|
/* According to the BIOS specification at:
|
|
* http://members.datafast.net.au/dft0802/specs/bios21.pdf, we could
|
|
* restrict the x zone to some pages and make it ro. But this may be
|
|
* broken on some bios, complex to handle with static_protections.
|
|
* We could make the 0xe0000-0x100000 range rox, but this can break
|
|
* some ISA mapping.
|
|
*
|
|
* So we let's an rw and x hole when pcibios is used. This shouldn't
|
|
* happen for modern system with mmconfig, and if you don't want it
|
|
* you could disable pcibios...
|
|
*/
|
|
static inline void set_bios_x(void)
|
|
{
|
|
pcibios_enabled = 1;
|
|
set_memory_x(PAGE_OFFSET + BIOS_BEGIN, (BIOS_END - BIOS_BEGIN) >> PAGE_SHIFT);
|
|
if (__supported_pte_mask & _PAGE_NX)
|
|
printk(KERN_INFO "PCI : PCI BIOS aera is rw and x. Use pci=nobios if you want it NX.\n");
|
|
}
|
|
|
|
/*
|
|
* This is the standard structure used to identify the entry point
|
|
* to the BIOS32 Service Directory, as documented in
|
|
* Standard BIOS 32-bit Service Directory Proposal
|
|
* Revision 0.4 May 24, 1993
|
|
* Phoenix Technologies Ltd.
|
|
* Norwood, MA
|
|
* and the PCI BIOS specification.
|
|
*/
|
|
|
|
union bios32 {
|
|
struct {
|
|
unsigned long signature; /* _32_ */
|
|
unsigned long entry; /* 32 bit physical address */
|
|
unsigned char revision; /* Revision level, 0 */
|
|
unsigned char length; /* Length in paragraphs should be 01 */
|
|
unsigned char checksum; /* All bytes must add up to zero */
|
|
unsigned char reserved[5]; /* Must be zero */
|
|
} fields;
|
|
char chars[16];
|
|
};
|
|
|
|
/*
|
|
* Physical address of the service directory. I don't know if we're
|
|
* allowed to have more than one of these or not, so just in case
|
|
* we'll make pcibios_present() take a memory start parameter and store
|
|
* the array there.
|
|
*/
|
|
|
|
static struct {
|
|
unsigned long address;
|
|
unsigned short segment;
|
|
} bios32_indirect = { 0, __KERNEL_CS };
|
|
|
|
/*
|
|
* Returns the entry point for the given service, NULL on error
|
|
*/
|
|
|
|
static unsigned long bios32_service(unsigned long service)
|
|
{
|
|
unsigned char return_code; /* %al */
|
|
unsigned long address; /* %ebx */
|
|
unsigned long length; /* %ecx */
|
|
unsigned long entry; /* %edx */
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
__asm__("lcall *(%%edi); cld"
|
|
: "=a" (return_code),
|
|
"=b" (address),
|
|
"=c" (length),
|
|
"=d" (entry)
|
|
: "0" (service),
|
|
"1" (0),
|
|
"D" (&bios32_indirect));
|
|
local_irq_restore(flags);
|
|
|
|
switch (return_code) {
|
|
case 0:
|
|
return address + entry;
|
|
case 0x80: /* Not present */
|
|
printk(KERN_WARNING "bios32_service(0x%lx): not present\n", service);
|
|
return 0;
|
|
default: /* Shouldn't happen */
|
|
printk(KERN_WARNING "bios32_service(0x%lx): returned 0x%x -- BIOS bug!\n",
|
|
service, return_code);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static struct {
|
|
unsigned long address;
|
|
unsigned short segment;
|
|
} pci_indirect = { 0, __KERNEL_CS };
|
|
|
|
static int pci_bios_present;
|
|
|
|
static int __devinit check_pcibios(void)
|
|
{
|
|
u32 signature, eax, ebx, ecx;
|
|
u8 status, major_ver, minor_ver, hw_mech;
|
|
unsigned long flags, pcibios_entry;
|
|
|
|
if ((pcibios_entry = bios32_service(PCI_SERVICE))) {
|
|
pci_indirect.address = pcibios_entry + PAGE_OFFSET;
|
|
|
|
local_irq_save(flags);
|
|
__asm__(
|
|
"lcall *(%%edi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=d" (signature),
|
|
"=a" (eax),
|
|
"=b" (ebx),
|
|
"=c" (ecx)
|
|
: "1" (PCIBIOS_PCI_BIOS_PRESENT),
|
|
"D" (&pci_indirect)
|
|
: "memory");
|
|
local_irq_restore(flags);
|
|
|
|
status = (eax >> 8) & 0xff;
|
|
hw_mech = eax & 0xff;
|
|
major_ver = (ebx >> 8) & 0xff;
|
|
minor_ver = ebx & 0xff;
|
|
if (pcibios_last_bus < 0)
|
|
pcibios_last_bus = ecx & 0xff;
|
|
DBG("PCI: BIOS probe returned s=%02x hw=%02x ver=%02x.%02x l=%02x\n",
|
|
status, hw_mech, major_ver, minor_ver, pcibios_last_bus);
|
|
if (status || signature != PCI_SIGNATURE) {
|
|
printk (KERN_ERR "PCI: BIOS BUG #%x[%08x] found\n",
|
|
status, signature);
|
|
return 0;
|
|
}
|
|
printk(KERN_INFO "PCI: PCI BIOS revision %x.%02x entry at 0x%lx, last bus=%d\n",
|
|
major_ver, minor_ver, pcibios_entry, pcibios_last_bus);
|
|
#ifdef CONFIG_PCI_DIRECT
|
|
if (!(hw_mech & PCIBIOS_HW_TYPE1))
|
|
pci_probe &= ~PCI_PROBE_CONF1;
|
|
if (!(hw_mech & PCIBIOS_HW_TYPE2))
|
|
pci_probe &= ~PCI_PROBE_CONF2;
|
|
#endif
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int pci_bios_read(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 *value)
|
|
{
|
|
unsigned long result = 0;
|
|
unsigned long flags;
|
|
unsigned long bx = (bus << 8) | devfn;
|
|
|
|
if (!value || (bus > 255) || (devfn > 255) || (reg > 255))
|
|
return -EINVAL;
|
|
|
|
raw_spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=c" (*value),
|
|
"=a" (result)
|
|
: "1" (PCIBIOS_READ_CONFIG_BYTE),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
/*
|
|
* Zero-extend the result beyond 8 bits, do not trust the
|
|
* BIOS having done it:
|
|
*/
|
|
*value &= 0xff;
|
|
break;
|
|
case 2:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=c" (*value),
|
|
"=a" (result)
|
|
: "1" (PCIBIOS_READ_CONFIG_WORD),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
/*
|
|
* Zero-extend the result beyond 16 bits, do not trust the
|
|
* BIOS having done it:
|
|
*/
|
|
*value &= 0xffff;
|
|
break;
|
|
case 4:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=c" (*value),
|
|
"=a" (result)
|
|
: "1" (PCIBIOS_READ_CONFIG_DWORD),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
break;
|
|
}
|
|
|
|
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return (int)((result & 0xff00) >> 8);
|
|
}
|
|
|
|
static int pci_bios_write(unsigned int seg, unsigned int bus,
|
|
unsigned int devfn, int reg, int len, u32 value)
|
|
{
|
|
unsigned long result = 0;
|
|
unsigned long flags;
|
|
unsigned long bx = (bus << 8) | devfn;
|
|
|
|
if ((bus > 255) || (devfn > 255) || (reg > 255))
|
|
return -EINVAL;
|
|
|
|
raw_spin_lock_irqsave(&pci_config_lock, flags);
|
|
|
|
switch (len) {
|
|
case 1:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=a" (result)
|
|
: "0" (PCIBIOS_WRITE_CONFIG_BYTE),
|
|
"c" (value),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
break;
|
|
case 2:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=a" (result)
|
|
: "0" (PCIBIOS_WRITE_CONFIG_WORD),
|
|
"c" (value),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
break;
|
|
case 4:
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=a" (result)
|
|
: "0" (PCIBIOS_WRITE_CONFIG_DWORD),
|
|
"c" (value),
|
|
"b" (bx),
|
|
"D" ((long)reg),
|
|
"S" (&pci_indirect));
|
|
break;
|
|
}
|
|
|
|
raw_spin_unlock_irqrestore(&pci_config_lock, flags);
|
|
|
|
return (int)((result & 0xff00) >> 8);
|
|
}
|
|
|
|
|
|
/*
|
|
* Function table for BIOS32 access
|
|
*/
|
|
|
|
static struct pci_raw_ops pci_bios_access = {
|
|
.read = pci_bios_read,
|
|
.write = pci_bios_write
|
|
};
|
|
|
|
/*
|
|
* Try to find PCI BIOS.
|
|
*/
|
|
|
|
static struct pci_raw_ops * __devinit pci_find_bios(void)
|
|
{
|
|
union bios32 *check;
|
|
unsigned char sum;
|
|
int i, length;
|
|
|
|
/*
|
|
* Follow the standard procedure for locating the BIOS32 Service
|
|
* directory by scanning the permissible address range from
|
|
* 0xe0000 through 0xfffff for a valid BIOS32 structure.
|
|
*/
|
|
|
|
for (check = (union bios32 *) __va(0xe0000);
|
|
check <= (union bios32 *) __va(0xffff0);
|
|
++check) {
|
|
long sig;
|
|
if (probe_kernel_address(&check->fields.signature, sig))
|
|
continue;
|
|
|
|
if (check->fields.signature != BIOS32_SIGNATURE)
|
|
continue;
|
|
length = check->fields.length * 16;
|
|
if (!length)
|
|
continue;
|
|
sum = 0;
|
|
for (i = 0; i < length ; ++i)
|
|
sum += check->chars[i];
|
|
if (sum != 0)
|
|
continue;
|
|
if (check->fields.revision != 0) {
|
|
printk("PCI: unsupported BIOS32 revision %d at 0x%p\n",
|
|
check->fields.revision, check);
|
|
continue;
|
|
}
|
|
DBG("PCI: BIOS32 Service Directory structure at 0x%p\n", check);
|
|
if (check->fields.entry >= 0x100000) {
|
|
printk("PCI: BIOS32 entry (0x%p) in high memory, "
|
|
"cannot use.\n", check);
|
|
return NULL;
|
|
} else {
|
|
unsigned long bios32_entry = check->fields.entry;
|
|
DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n",
|
|
bios32_entry);
|
|
bios32_indirect.address = bios32_entry + PAGE_OFFSET;
|
|
set_bios_x();
|
|
if (check_pcibios())
|
|
return &pci_bios_access;
|
|
}
|
|
break; /* Hopefully more than one BIOS32 cannot happen... */
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* BIOS Functions for IRQ Routing
|
|
*/
|
|
|
|
struct irq_routing_options {
|
|
u16 size;
|
|
struct irq_info *table;
|
|
u16 segment;
|
|
} __attribute__((packed));
|
|
|
|
struct irq_routing_table * pcibios_get_irq_routing_table(void)
|
|
{
|
|
struct irq_routing_options opt;
|
|
struct irq_routing_table *rt = NULL;
|
|
int ret, map;
|
|
unsigned long page;
|
|
|
|
if (!pci_bios_present)
|
|
return NULL;
|
|
page = __get_free_page(GFP_KERNEL);
|
|
if (!page)
|
|
return NULL;
|
|
opt.table = (struct irq_info *) page;
|
|
opt.size = PAGE_SIZE;
|
|
opt.segment = __KERNEL_DS;
|
|
|
|
DBG("PCI: Fetching IRQ routing table... ");
|
|
__asm__("push %%es\n\t"
|
|
"push %%ds\n\t"
|
|
"pop %%es\n\t"
|
|
"lcall *(%%esi); cld\n\t"
|
|
"pop %%es\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=a" (ret),
|
|
"=b" (map),
|
|
"=m" (opt)
|
|
: "0" (PCIBIOS_GET_ROUTING_OPTIONS),
|
|
"1" (0),
|
|
"D" ((long) &opt),
|
|
"S" (&pci_indirect),
|
|
"m" (opt)
|
|
: "memory");
|
|
DBG("OK ret=%d, size=%d, map=%x\n", ret, opt.size, map);
|
|
if (ret & 0xff00)
|
|
printk(KERN_ERR "PCI: Error %02x when fetching IRQ routing table.\n", (ret >> 8) & 0xff);
|
|
else if (opt.size) {
|
|
rt = kmalloc(sizeof(struct irq_routing_table) + opt.size, GFP_KERNEL);
|
|
if (rt) {
|
|
memset(rt, 0, sizeof(struct irq_routing_table));
|
|
rt->size = opt.size + sizeof(struct irq_routing_table);
|
|
rt->exclusive_irqs = map;
|
|
memcpy(rt->slots, (void *) page, opt.size);
|
|
printk(KERN_INFO "PCI: Using BIOS Interrupt Routing Table\n");
|
|
}
|
|
}
|
|
free_page(page);
|
|
return rt;
|
|
}
|
|
EXPORT_SYMBOL(pcibios_get_irq_routing_table);
|
|
|
|
int pcibios_set_irq_routing(struct pci_dev *dev, int pin, int irq)
|
|
{
|
|
int ret;
|
|
|
|
__asm__("lcall *(%%esi); cld\n\t"
|
|
"jc 1f\n\t"
|
|
"xor %%ah, %%ah\n"
|
|
"1:"
|
|
: "=a" (ret)
|
|
: "0" (PCIBIOS_SET_PCI_HW_INT),
|
|
"b" ((dev->bus->number << 8) | dev->devfn),
|
|
"c" ((irq << 8) | (pin + 10)),
|
|
"S" (&pci_indirect));
|
|
return !(ret & 0xff00);
|
|
}
|
|
EXPORT_SYMBOL(pcibios_set_irq_routing);
|
|
|
|
void __init pci_pcbios_init(void)
|
|
{
|
|
if ((pci_probe & PCI_PROBE_BIOS)
|
|
&& ((raw_pci_ops = pci_find_bios()))) {
|
|
pci_bios_present = 1;
|
|
}
|
|
}
|
|
|