2 * BIOS32 and PCI BIOS handling.
6 #include <linux/init.h>
7 #include <linux/module.h>
8 #include <linux/uaccess.h>
9 #include <asm/pci_x86.h>
10 #include <asm/pci-functions.h>
12 /* BIOS32 signature: "_32_" */
13 #define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24))
15 /* PCI signature: "PCI " */
16 #define PCI_SIGNATURE (('P' << 0) + ('C' << 8) + ('I' << 16) + (' ' << 24))
18 /* PCI service signature: "$PCI" */
19 #define PCI_SERVICE (('$' << 0) + ('P' << 8) + ('C' << 16) + ('I' << 24))
21 /* PCI BIOS hardware mechanism flags */
22 #define PCIBIOS_HW_TYPE1 0x01
23 #define PCIBIOS_HW_TYPE2 0x02
24 #define PCIBIOS_HW_TYPE1_SPEC 0x10
25 #define PCIBIOS_HW_TYPE2_SPEC 0x20
28 * This is the standard structure used to identify the entry point
29 * to the BIOS32 Service Directory, as documented in
30 * Standard BIOS 32-bit Service Directory Proposal
31 * Revision 0.4 May 24, 1993
32 * Phoenix Technologies Ltd.
34 * and the PCI BIOS specification.
39 unsigned long signature
; /* _32_ */
40 unsigned long entry
; /* 32 bit physical address */
41 unsigned char revision
; /* Revision level, 0 */
42 unsigned char length
; /* Length in paragraphs should be 01 */
43 unsigned char checksum
; /* All bytes must add up to zero */
44 unsigned char reserved
[5]; /* Must be zero */
50 * Physical address of the service directory. I don't know if we're
51 * allowed to have more than one of these or not, so just in case
52 * we'll make pcibios_present() take a memory start parameter and store
57 unsigned long address
;
58 unsigned short segment
;
59 } bios32_indirect
= { 0, __KERNEL_CS
};
62 * Returns the entry point for the given service, NULL on error
65 static unsigned long bios32_service(unsigned long service
)
67 unsigned char return_code
; /* %al */
68 unsigned long address
; /* %ebx */
69 unsigned long length
; /* %ecx */
70 unsigned long entry
; /* %edx */
73 local_irq_save(flags
);
74 __asm__("lcall *(%%edi); cld"
81 "D" (&bios32_indirect
));
82 local_irq_restore(flags
);
84 switch (return_code
) {
86 return address
+ entry
;
87 case 0x80: /* Not present */
88 printk(KERN_WARNING
"bios32_service(0x%lx): not present\n", service
);
90 default: /* Shouldn't happen */
91 printk(KERN_WARNING
"bios32_service(0x%lx): returned 0x%x -- BIOS bug!\n",
92 service
, return_code
);
98 unsigned long address
;
99 unsigned short segment
;
100 } pci_indirect
= { 0, __KERNEL_CS
};
102 static int pci_bios_present
;
104 static int __devinit
check_pcibios(void)
106 u32 signature
, eax
, ebx
, ecx
;
107 u8 status
, major_ver
, minor_ver
, hw_mech
;
108 unsigned long flags
, pcibios_entry
;
110 if ((pcibios_entry
= bios32_service(PCI_SERVICE
))) {
111 pci_indirect
.address
= pcibios_entry
+ PAGE_OFFSET
;
113 local_irq_save(flags
);
115 "lcall *(%%edi); cld\n\t"
123 : "1" (PCIBIOS_PCI_BIOS_PRESENT
),
126 local_irq_restore(flags
);
128 status
= (eax
>> 8) & 0xff;
129 hw_mech
= eax
& 0xff;
130 major_ver
= (ebx
>> 8) & 0xff;
131 minor_ver
= ebx
& 0xff;
132 if (pcibios_last_bus
< 0)
133 pcibios_last_bus
= ecx
& 0xff;
134 DBG("PCI: BIOS probe returned s=%02x hw=%02x ver=%02x.%02x l=%02x\n",
135 status
, hw_mech
, major_ver
, minor_ver
, pcibios_last_bus
);
136 if (status
|| signature
!= PCI_SIGNATURE
) {
137 printk (KERN_ERR
"PCI: BIOS BUG #%x[%08x] found\n",
141 printk(KERN_INFO
"PCI: PCI BIOS revision %x.%02x entry at 0x%lx, last bus=%d\n",
142 major_ver
, minor_ver
, pcibios_entry
, pcibios_last_bus
);
143 #ifdef CONFIG_PCI_DIRECT
144 if (!(hw_mech
& PCIBIOS_HW_TYPE1
))
145 pci_probe
&= ~PCI_PROBE_CONF1
;
146 if (!(hw_mech
& PCIBIOS_HW_TYPE2
))
147 pci_probe
&= ~PCI_PROBE_CONF2
;
154 static int pci_bios_read(unsigned int seg
, unsigned int bus
,
155 unsigned int devfn
, int reg
, int len
, u32
*value
)
157 unsigned long result
= 0;
159 unsigned long bx
= (bus
<< 8) | devfn
;
161 if (!value
|| (bus
> 255) || (devfn
> 255) || (reg
> 255))
164 spin_lock_irqsave(&pci_config_lock
, flags
);
168 __asm__("lcall *(%%esi); cld\n\t"
174 : "1" (PCIBIOS_READ_CONFIG_BYTE
),
177 "S" (&pci_indirect
));
179 * Zero-extend the result beyond 8 bits, do not trust the
180 * BIOS having done it:
185 __asm__("lcall *(%%esi); cld\n\t"
191 : "1" (PCIBIOS_READ_CONFIG_WORD
),
194 "S" (&pci_indirect
));
196 * Zero-extend the result beyond 16 bits, do not trust the
197 * BIOS having done it:
202 __asm__("lcall *(%%esi); cld\n\t"
208 : "1" (PCIBIOS_READ_CONFIG_DWORD
),
211 "S" (&pci_indirect
));
215 spin_unlock_irqrestore(&pci_config_lock
, flags
);
217 return (int)((result
& 0xff00) >> 8);
220 static int pci_bios_write(unsigned int seg
, unsigned int bus
,
221 unsigned int devfn
, int reg
, int len
, u32 value
)
223 unsigned long result
= 0;
225 unsigned long bx
= (bus
<< 8) | devfn
;
227 if ((bus
> 255) || (devfn
> 255) || (reg
> 255))
230 spin_lock_irqsave(&pci_config_lock
, flags
);
234 __asm__("lcall *(%%esi); cld\n\t"
239 : "0" (PCIBIOS_WRITE_CONFIG_BYTE
),
243 "S" (&pci_indirect
));
246 __asm__("lcall *(%%esi); cld\n\t"
251 : "0" (PCIBIOS_WRITE_CONFIG_WORD
),
255 "S" (&pci_indirect
));
258 __asm__("lcall *(%%esi); cld\n\t"
263 : "0" (PCIBIOS_WRITE_CONFIG_DWORD
),
267 "S" (&pci_indirect
));
271 spin_unlock_irqrestore(&pci_config_lock
, flags
);
273 return (int)((result
& 0xff00) >> 8);
278 * Function table for BIOS32 access
281 static struct pci_raw_ops pci_bios_access
= {
282 .read
= pci_bios_read
,
283 .write
= pci_bios_write
287 * Try to find PCI BIOS.
290 static struct pci_raw_ops
* __devinit
pci_find_bios(void)
297 * Follow the standard procedure for locating the BIOS32 Service
298 * directory by scanning the permissible address range from
299 * 0xe0000 through 0xfffff for a valid BIOS32 structure.
302 for (check
= (union bios32
*) __va(0xe0000);
303 check
<= (union bios32
*) __va(0xffff0);
306 if (probe_kernel_address(&check
->fields
.signature
, sig
))
309 if (check
->fields
.signature
!= BIOS32_SIGNATURE
)
311 length
= check
->fields
.length
* 16;
315 for (i
= 0; i
< length
; ++i
)
316 sum
+= check
->chars
[i
];
319 if (check
->fields
.revision
!= 0) {
320 printk("PCI: unsupported BIOS32 revision %d at 0x%p\n",
321 check
->fields
.revision
, check
);
324 DBG("PCI: BIOS32 Service Directory structure at 0x%p\n", check
);
325 if (check
->fields
.entry
>= 0x100000) {
326 printk("PCI: BIOS32 entry (0x%p) in high memory, "
327 "cannot use.\n", check
);
330 unsigned long bios32_entry
= check
->fields
.entry
;
331 DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n",
333 bios32_indirect
.address
= bios32_entry
+ PAGE_OFFSET
;
335 return &pci_bios_access
;
337 break; /* Hopefully more than one BIOS32 cannot happen... */
344 * BIOS Functions for IRQ Routing
347 struct irq_routing_options
{
349 struct irq_info
*table
;
351 } __attribute__((packed
));
353 struct irq_routing_table
* pcibios_get_irq_routing_table(void)
355 struct irq_routing_options opt
;
356 struct irq_routing_table
*rt
= NULL
;
360 if (!pci_bios_present
)
362 page
= __get_free_page(GFP_KERNEL
);
365 opt
.table
= (struct irq_info
*) page
;
366 opt
.size
= PAGE_SIZE
;
367 opt
.segment
= __KERNEL_DS
;
369 DBG("PCI: Fetching IRQ routing table... ");
370 __asm__("push %%es\n\t"
373 "lcall *(%%esi); cld\n\t"
381 : "0" (PCIBIOS_GET_ROUTING_OPTIONS
),
387 DBG("OK ret=%d, size=%d, map=%x\n", ret
, opt
.size
, map
);
389 printk(KERN_ERR
"PCI: Error %02x when fetching IRQ routing table.\n", (ret
>> 8) & 0xff);
391 rt
= kmalloc(sizeof(struct irq_routing_table
) + opt
.size
, GFP_KERNEL
);
393 memset(rt
, 0, sizeof(struct irq_routing_table
));
394 rt
->size
= opt
.size
+ sizeof(struct irq_routing_table
);
395 rt
->exclusive_irqs
= map
;
396 memcpy(rt
->slots
, (void *) page
, opt
.size
);
397 printk(KERN_INFO
"PCI: Using BIOS Interrupt Routing Table\n");
403 EXPORT_SYMBOL(pcibios_get_irq_routing_table
);
405 int pcibios_set_irq_routing(struct pci_dev
*dev
, int pin
, int irq
)
409 __asm__("lcall *(%%esi); cld\n\t"
414 : "0" (PCIBIOS_SET_PCI_HW_INT
),
415 "b" ((dev
->bus
->number
<< 8) | dev
->devfn
),
416 "c" ((irq
<< 8) | (pin
+ 10)),
417 "S" (&pci_indirect
));
418 return !(ret
& 0xff00);
420 EXPORT_SYMBOL(pcibios_set_irq_routing
);
422 void __init
pci_pcbios_init(void)
424 if ((pci_probe
& PCI_PROBE_BIOS
)
425 && ((raw_pci_ops
= pci_find_bios()))) {
426 pci_bios_present
= 1;