diff options
Diffstat (limited to 'arch/x86/lib/bios_pci.S')
| -rw-r--r-- | arch/x86/lib/bios_pci.S | 92 |
1 files changed, 63 insertions, 29 deletions
diff --git a/arch/x86/lib/bios_pci.S b/arch/x86/lib/bios_pci.S index 53d2ea047..47c478b27 100644 --- a/arch/x86/lib/bios_pci.S +++ b/arch/x86/lib/bios_pci.S @@ -80,11 +80,15 @@ cs incl num_pci_bios_present #endif movl $0x20494350, %eax gs movl %eax, OFFS_EDX(%bp) + + /* We support cfg type 1 version 2.10 */ movb $0x01, %al -gs movb %al, OFFS_AL(%bp) /* We support cfg type 1 */ - movw $0x0210, %ax /* version 2.10 */ +gs movb %al, OFFS_AL(%bp) + movw $0x0210, %ax gs movw %ax, OFFS_BX(%bp) -cs movb pci_last_bus, %al /* last bus number */ + + /* last bus number */ +cs movb pci_last_bus, %al gs movb %al, OFFS_CL(%bp) jmp clear_carry @@ -97,16 +101,22 @@ cs incl num_pci_bios_find_device #endif gs movw OFFS_CX(%bp), %di shll $16, %edi -gs movw OFFS_DX(%bp), %di /* edi now holds device in upper 16 - * bits and vendor in lower 16 bits */ +gs movw OFFS_DX(%bp), %di + /* edi now holds device in upper 16 bits and vendor in lower 16 bits */ + gs movw OFFS_SI(%bp), %si - xorw %bx, %bx /* start at bus 0 dev 0 function 0 */ + + /* start at bus 0 dev 0 function 0 */ + xorw %bx, %bx pfd_loop: - xorw %ax, %ax /* dword 0 is vendor/device */ + /* dword 0 is vendor/device */ + xorw %ax, %ax call __pci_bios_select_register movw $0xcfc, %dx inl %dx, %eax - cmpl %edi, %eax /* our device ? */ + + /* our device ? */ + cmpl %edi, %eax je pfd_found_one pfd_next_dev: /* check for multi function devices */ @@ -120,13 +130,16 @@ pfd_next_dev: andb $0x80, %al jz pfd_not_multi_function pfd_function_not_zero: - incw %bx /* next function, overflows in to - * device number, then bus number */ + /* next function, overflows in to device number, then bus number */ + incw %bx jmp pfd_check_bus pfd_not_multi_function: - andw $0xfff8, %bx /* remove function bits */ - addw $0x0008, %bx /* next device, overflows in to bus number */ + /* remove function bits */ + andw $0xfff8, %bx + + /* next device, overflows in to bus number */ + addw $0x0008, %bx pfd_check_bus: cs movb pci_last_bus, %ah cmpb %ah, %bh @@ -142,7 +155,8 @@ gs movw %bx, OFFS_BX(%bp) jmp clear_carry pfd_not_found: - movb $0x86, %ah /* device not found */ + /* device not found */ + movb $0x86, %ah jmp set_carry /*****************************************************************************/ @@ -152,17 +166,24 @@ pci_bios_find_class: cs incl num_pci_bios_find_class #endif gs movl OFFS_ECX(%bp), %edi - andl $0x00ffffff, %edi /* edi now holds class-code in lower 24 bits */ + + /* edi now holds class-code in lower 24 bits */ + andl $0x00ffffff, %edi gs movw OFFS_SI(%bp), %si - xorw %bx, %bx /* start at bus 0 dev 0 function 0 */ + + /* start at bus 0 dev 0 function 0 */ + xorw %bx, %bx pfc_loop: - movw $8, %ax /* dword 8 is class-code high 24bits */ + /* dword 8 is class-code high 24bits */ + movw $8, %ax call __pci_bios_select_register movw $0xcfc, %dx inl %dx, %eax shrl $8, %eax andl $0x00ffffff, %eax - cmpl %edi, %eax /* our device ? */ + + /* our device ? */ + cmpl %edi, %eax je pfc_found_one pfc_next_dev: /* check for multi function devices */ @@ -175,13 +196,16 @@ pfc_next_dev: andb $0x80, %al jz pfc_not_multi_function pfc_function_not_zero: - incw %bx /* next function, overflows in to - * device number, then bus number */ + /* next function, overflows in to device number, then bus number */ + incw %bx jmp pfc_check_bus pfc_not_multi_function: - andw $0xfff8, %bx /* remove function bits */ - addw $0x0008, %bx /* next device, overflows in to bus number */ + /* remove function bits */ + andw $0xfff8, %bx + + /* next device, overflows in to bus number */ + addw $0x0008, %bx pfc_check_bus: cs movb pci_last_bus, %ah cmpb %ah, %bh @@ -197,7 +221,8 @@ gs movw %bx, OFFS_BX(%bp) jmp clear_carry pfc_not_found: - movb $0x86, %ah /* device not found */ + /* device not found */ + movb $0x86, %ah jmp set_carry /*****************************************************************************/ @@ -206,7 +231,8 @@ pci_bios_generate_special_cycle: #ifdef PCI_BIOS_DEBUG cs incl num_pci_bios_generate_special_cycle #endif - movb $0x81, %ah /* function not supported */ + /* function not supported */ + movb $0x81, %ah jmp set_carry /*****************************************************************************/ @@ -296,7 +322,8 @@ pci_bios_get_irq_routing: #ifdef PCI_BIOS_DEBUG cs incl num_pci_bios_get_irq_routing #endif - movb $0x81, %ah /* function not supported */ + /* function not supported */ + movb $0x81, %ah jmp set_carry /*****************************************************************************/ @@ -305,7 +332,8 @@ pci_bios_set_irq: #ifdef PCI_BIOS_DEBUG cs incl num_pci_bios_set_irq #endif - movb $0x81, %ah /* function not supported */ + /* function not supported */ + movb $0x81, %ah jmp set_carry /*****************************************************************************/ @@ -314,7 +342,8 @@ unknown_function: #ifdef PCI_BIOS_DEBUG cs incl num_pci_bios_unknown_function #endif - movb $0x81, %ah /* function not supported */ + /* function not supported */ + movb $0x81, %ah jmp set_carry /*****************************************************************************/ @@ -323,7 +352,8 @@ pci_bios_select_register: gs movw OFFS_BX(%bp), %bx gs movw OFFS_DI(%bp), %ax /* destroys eax, dx */ -__pci_bios_select_register: /* BX holds device id, AX holds register index */ +__pci_bios_select_register: + /* BX holds device id, AX holds register index */ pushl %ebx andl $0xfc, %eax andl $0xffff, %ebx @@ -338,7 +368,9 @@ __pci_bios_select_register: /* BX holds device id, AX holds regist clear_carry: gs movw OFFS_FLAGS(%bp), %ax - andw $0xfffe, %ax /* clear carry -- function succeeded */ + + /* clear carry -- function succeeded */ + andw $0xfffe, %ax gs movw %ax, OFFS_FLAGS(%bp) xorw %ax, %ax gs movb %ah, OFFS_AH(%bp) @@ -347,7 +379,9 @@ gs movb %ah, OFFS_AH(%bp) set_carry: gs movb %ah, OFFS_AH(%bp) gs movw OFFS_FLAGS(%bp), %ax - orw $1, %ax /* return carry -- function not supported */ + + /* return carry -- function not supported */ + orw $1, %ax gs movw %ax, OFFS_FLAGS(%bp) movw $-1, %ax ret |