diff options
Diffstat (limited to 'lib_i386/bios_pci.S')
| -rw-r--r-- | lib_i386/bios_pci.S | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/lib_i386/bios_pci.S b/lib_i386/bios_pci.S new file mode 100644 index 0000000..e53791a --- /dev/null +++ b/lib_i386/bios_pci.S @@ -0,0 +1,411 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB, daniel@omicron.se + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +/* + * x86 realmode assembly implementation of a PCI BIOS + * for platforms that use one PCI hose and configuration + * access type 1. (The common case for low-end PC's) + */ + +#include "bios.h" + +#define PCI_BIOS_DEBUG + +.section .bios, "ax" +.code16 +.globl realmode_pci_bios_call_entry +realmode_pci_bios_call_entry: + MAKE_BIOS_STACK + call realmode_pci_bios + RESTORE_CALLERS_STACK + ret + + +.globl realmode_pci_bios +realmode_pci_bios: +gs movw OFFS_AX(%bp), %ax + cmpb $1, %al + je pci_bios_present + cmpb $2, %al + je pci_bios_find_device + cmpb $3, %al + je pci_bios_find_class + cmpb $6, %al + je pci_bios_generate_special_cycle + cmpb $8, %al + je pci_bios_read_cfg_byte + cmpb $9, %al + je pci_bios_read_cfg_word + cmpb $10, %al + je pci_bios_read_cfg_dword + cmpb $11, %al + je pci_bios_write_cfg_byte + cmpb $12, %al + je pci_bios_write_cfg_word + cmpb $13, %al + je pci_bios_write_cfg_dword + cmpb $14, %al + je pci_bios_get_irq_routing + cmpb $15, %al + je pci_bios_set_irq + jmp unknown_function + +/*****************************************************************************/ + +pci_bios_present: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_present +#endif + movl $0x20494350, %eax +gs movl %eax, OFFS_EDX(%bp) + movb $0x01, %al +gs movb %al, OFFS_AL(%bp) /* We support cfg type 1 */ + movw $0x0210, %ax /* version 2.10 */ +gs movw %ax, OFFS_BX(%bp) +cs movb pci_last_bus, %al /* last bus number */ +gs movb %al, OFFS_CL(%bp) + jmp clear_carry + +/*****************************************************************************/ + +/* device 0-31, function 0-7 */ +pci_bios_find_device: +#ifdef PCI_BIOS_DEBUG +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_SI(%bp), %si + xorw %bx, %bx /* start at bus 0 dev 0 function 0 */ +pfd_loop: + xorw %ax, %ax /* dword 0 is vendor/device */ + call __pci_bios_select_register + movw $0xcfc, %dx + inl %dx, %eax + cmpl %edi, %eax /* our device ? */ + je pfd_found_one +pfd_next_dev: + /* check for multi function devices */ + movw %bx, %ax + andw $3, %ax + jnz pfd_function_not_zero + movw $0x000c, %ax + call __pci_bios_select_register + movw $0xcfe, %dx + inb %dx, %al + andb $0x80, %al + jz pfd_not_multi_function +pfd_function_not_zero: + incw %bx /* next function, overflows in to + * device number, then bus number */ + jmp pfd_check_bus + +pfd_not_multi_function: + andw $0xfff8, %bx /* remove function bits */ + addw $0x0008, %bx /* next device, overflows in to bus number */ +pfd_check_bus: +cs movb pci_last_bus, %ah + cmpb %ah, %bh + ja pfd_not_found + jmp pfd_loop +pfd_found_one: + decw %si + js pfd_done + jmp pfd_next_dev + +pfd_done: +gs movw %bx, OFFS_BX(%bp) + jmp clear_carry + +pfd_not_found: + movb $0x86, %ah /* device not found */ + jmp set_carry + +/*****************************************************************************/ + +pci_bios_find_class: +#ifdef PCI_BIOS_DEBUG +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 */ +gs movw OFFS_SI(%bp), %si + xorw %bx, %bx /* start at bus 0 dev 0 function 0 */ +pfc_loop: + movw $8, %ax /* dword 8 is class-code high 24bits */ + call __pci_bios_select_register + movw $0xcfc, %dx + inl %dx, %eax + shrl $8, %eax + andl $0x00ffffff, %eax + cmpl %edi, %eax /* our device ? */ + je pfc_found_one +pfc_next_dev: + /* check for multi function devices */ + andw $3, %bx + jnz pfc_function_not_zero + movw $0x000c, %ax + call __pci_bios_select_register + movw $0xcfe, %dx + inb %dx, %al + andb $0x80, %al + jz pfc_not_multi_function +pfc_function_not_zero: + incw %bx /* next function, overflows in to + * device number, then bus number */ + jmp pfc_check_bus + +pfc_not_multi_function: + andw $0xfff8, %bx /* remove function bits */ + addw $0x0008, %bx /* next device, overflows in to bus number */ +pfc_check_bus: +cs movb pci_last_bus, %ah + cmpb %ah, %bh + ja pfc_not_found + jmp pfc_loop +pfc_found_one: + decw %si + js pfc_done + jmp pfc_next_dev + +pfc_done: +gs movw %bx, OFFS_BX(%bp) + jmp clear_carry + +pfc_not_found: + movb $0x86, %ah /* device not found */ + jmp set_carry + +/*****************************************************************************/ + +pci_bios_generate_special_cycle: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_generate_special_cycle +#endif + movb $0x81, %ah /* function not supported */ + jmp set_carry + +/*****************************************************************************/ + +pci_bios_read_cfg_byte: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_read_cfg_byte +#endif + call pci_bios_select_register +gs movw OFFS_DI(%bp), %dx + andw $3, %dx + addw $0xcfc, %dx + inb %dx, %al +gs movb %al, OFFS_CL(%bp) + jmp clear_carry + +/*****************************************************************************/ + +pci_bios_read_cfg_word: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_read_cfg_word +#endif + call pci_bios_select_register +gs movw OFFS_DI(%bp), %dx + andw $2, %dx + addw $0xcfc, %dx + inw %dx, %ax +gs movw %ax, OFFS_CX(%bp) + jmp clear_carry + + +/*****************************************************************************/ + +pci_bios_read_cfg_dword: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_read_cfg_dword +#endif + call pci_bios_select_register + movw $0xcfc, %dx + inl %dx, %eax +gs movl %eax, OFFS_ECX(%bp) + jmp clear_carry + +/*****************************************************************************/ + +pci_bios_write_cfg_byte: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_write_cfg_byte +#endif + call pci_bios_select_register +gs movw OFFS_DI(%bp), %dx +gs movb OFFS_CL(%bp), %al + andw $3, %dx + addw $0xcfc, %dx + outb %al, %dx + jmp clear_carry + +/*****************************************************************************/ + +pci_bios_write_cfg_word: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_write_cfg_word +#endif + call pci_bios_select_register +gs movw OFFS_DI(%bp), %dx +gs movw OFFS_CX(%bp), %ax + andw $2, %dx + addw $0xcfc, %dx + outw %ax, %dx + jmp clear_carry + +/*****************************************************************************/ + +pci_bios_write_cfg_dword: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_write_cfg_dword +#endif + call pci_bios_select_register +gs movl OFFS_ECX(%bp), %eax + movw $0xcfc, %dx + outl %eax, %dx + jmp clear_carry + +/*****************************************************************************/ + +pci_bios_get_irq_routing: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_get_irq_routing +#endif + movb $0x81, %ah /* function not supported */ + jmp set_carry + +/*****************************************************************************/ + +pci_bios_set_irq: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_set_irq +#endif + movb $0x81, %ah /* function not supported */ + jmp set_carry + +/*****************************************************************************/ + +unknown_function: +#ifdef PCI_BIOS_DEBUG +cs incl num_pci_bios_unknown_function +#endif + movb $0x81, %ah /* function not supported */ + jmp set_carry + +/*****************************************************************************/ + +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 */ + pushl %ebx + andl $0xfc, %eax + andl $0xffff, %ebx + shll $8, %ebx + orl %ebx, %eax + orl $0x80000000, %eax + movw $0xcf8, %dx + outl %eax, %dx + popl %ebx + ret + + +clear_carry: +gs movw OFFS_FLAGS(%bp), %ax + andw $0xfffe, %ax /* clear carry -- function succeeded */ +gs movw %ax, OFFS_FLAGS(%bp) + xorw %ax, %ax +gs movb %ah, OFFS_AH(%bp) + ret + +set_carry: +gs movb %ah, OFFS_AH(%bp) +gs movw OFFS_FLAGS(%bp), %ax + orw $1, %ax /* return carry -- function not supported */ +gs movw %ax, OFFS_FLAGS(%bp) + movw $-1, %ax + ret + +/*****************************************************************************/ + +.globl pci_last_bus +pci_last_bus: + .byte 0 + +#ifdef PCI_BIOS_DEBUG +.globl num_pci_bios_present +num_pci_bios_present: + .long 0 + +.globl num_pci_bios_find_device +num_pci_bios_find_device: + .long 0 + +.globl num_pci_bios_find_class +num_pci_bios_find_class: + .long 0 + +.globl num_pci_bios_generate_special_cycle +num_pci_bios_generate_special_cycle: + .long 0 + +.globl num_pci_bios_read_cfg_byte +num_pci_bios_read_cfg_byte: + .long 0 + +.globl num_pci_bios_read_cfg_word +num_pci_bios_read_cfg_word: + .long 0 + +.globl num_pci_bios_read_cfg_dword +num_pci_bios_read_cfg_dword: + .long 0 + +.globl num_pci_bios_write_cfg_byte +num_pci_bios_write_cfg_byte: + .long 0 + +.globl num_pci_bios_write_cfg_word +num_pci_bios_write_cfg_word: + .long 0 + +.globl num_pci_bios_write_cfg_dword +num_pci_bios_write_cfg_dword: + .long 0 + +.globl num_pci_bios_get_irq_routing +num_pci_bios_get_irq_routing: + .long 0 + +.globl num_pci_bios_set_irq +num_pci_bios_set_irq: + .long 0 + +.globl num_pci_bios_unknown_function +num_pci_bios_unknown_function: + .long 0 +#endif |