| /* At entry, the processor is in 16 bit real mode and the code is being |
| * executed from an address it was not linked to. Code must be pic and |
| * 32 bit sensitive until things are fixed up. |
| * |
| * Also be very careful as the stack is at the rear end of the interrupt |
| * table so using a noticeable amount of stack space is a no-no. |
| */ |
| |
| FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ) |
| |
| #include <librm.h> |
| #include <config/general.h> |
| #include <config/branding.h> |
| |
| #define PNP_SIGNATURE ( '$' + ( 'P' << 8 ) + ( 'n' << 16 ) + ( 'P' << 24 ) ) |
| #define PMM_SIGNATURE ( '$' + ( 'P' << 8 ) + ( 'M' << 16 ) + ( 'M' << 24 ) ) |
| #define PCI_SIGNATURE ( 'P' + ( 'C' << 8 ) + ( 'I' << 16 ) + ( ' ' << 24 ) ) |
| #define STACK_MAGIC ( 'L' + ( 'R' << 8 ) + ( 'E' << 16 ) + ( 'T' << 24 ) ) |
| #define PMM_ALLOCATE 0x0000 |
| #define PMM_FIND 0x0001 |
| #define PMM_HANDLE_BASE ( ( ( 'F' - 'A' + 1 ) << 26 ) + \ |
| ( ( 'E' - 'A' + 1 ) << 21 ) + \ |
| ( ( 'N' - 'A' + 1 ) << 16 ) ) |
| #define PMM_HANDLE_BASE_IMAGE_SOURCE \ |
| ( PMM_HANDLE_BASE | 0x00001000 ) |
| #define PMM_HANDLE_BASE_DECOMPRESS_TO \ |
| ( PMM_HANDLE_BASE | 0x00002000 ) |
| #define PCI_FUNC_MASK 0x07 |
| |
| /* ROM banner timeout, converted to a number of (18Hz) timer ticks. */ |
| #define ROM_BANNER_TIMEOUT_TICKS ( ( 18 * ROM_BANNER_TIMEOUT ) / 10 ) |
| |
| /* Allow payload to be excluded from ROM size |
| */ |
| #if ROMPREFIX_EXCLUDE_PAYLOAD |
| #define ZINFO_TYPE_ADxB "ADHB" |
| #define ZINFO_TYPE_ADxW "ADHW" |
| #else |
| #define ZINFO_TYPE_ADxB "ADDB" |
| #define ZINFO_TYPE_ADxW "ADDW" |
| #endif |
| |
| /* Allow ROM to be marked as containing multiple images |
| */ |
| #if ROMPREFIX_MORE_IMAGES |
| #define INDICATOR 0x00 |
| #else |
| #define INDICATOR 0x80 |
| #endif |
| |
| /* Default to building a PCI ROM if no bus type is specified |
| */ |
| #ifndef BUSTYPE |
| #define BUSTYPE "PCIR" |
| #endif |
| |
| .section ".note.GNU-stack", "", @progbits |
| .code16 |
| .arch i386 |
| .section ".prefix", "ax", @progbits |
| .globl _rom_start |
| _rom_start: |
| |
| .org 0x00 |
| romheader: |
| .word 0xAA55 /* BIOS extension signature */ |
| romheader_size: .byte 0 /* Size in 512-byte blocks */ |
| jmp init /* Initialisation vector */ |
| checksum: |
| .byte 0 |
| .org 0x10 |
| .word ipxeheader |
| .org 0x16 |
| .word undiheader |
| .ifeqs BUSTYPE, "PCIR" |
| .org 0x18 |
| .word pciheader |
| .endif |
| .org 0x1a |
| .word pnpheader |
| .size romheader, . - romheader |
| |
| .section ".zinfo.fixup", "a", @progbits /* Compressor fixups */ |
| .ascii ZINFO_TYPE_ADxB |
| .long romheader_size |
| .long 512 |
| .long 0 |
| .previous |
| |
| .ifeqs BUSTYPE, "PCIR" |
| .balign 4 |
| pciheader: |
| .ascii "PCIR" /* Signature */ |
| .word pci_vendor_id /* Vendor identification */ |
| .word pci_device_id /* Device identification */ |
| .word ( pci_devlist - pciheader ) /* Device list pointer */ |
| .word pciheader_len /* PCI data structure length */ |
| .byte 0x03 /* PCI data structure revision */ |
| .byte 0x00, 0x00, 0x02 /* Class code */ |
| pciheader_image_length: |
| .word 0 /* Image length */ |
| .word 0x0001 /* Revision level */ |
| .byte 0x00 /* Code type */ |
| .byte INDICATOR /* Last image indicator */ |
| pciheader_runtime_length: |
| .word 0 /* Maximum run-time image length */ |
| .word 0x0000 /* Configuration utility code header */ |
| .word 0x0000 /* DMTF CLP entry point */ |
| .equ pciheader_len, . - pciheader |
| .size pciheader, . - pciheader |
| |
| /* PCI additional device list (filled in by linker) */ |
| .section ".pci_devlist.00000000", "a", @progbits |
| pci_devlist: |
| .previous |
| .section ".pci_devlist.ffffffff", "a", @progbits |
| pci_devlist_end: |
| .short 0x0000 /* List terminator */ |
| .previous |
| /* Ensure that terminator is always present */ |
| .reloc pciheader, RELOC_TYPE_NONE, pci_devlist_end |
| |
| .section ".zinfo.fixup", "a", @progbits /* Compressor fixups */ |
| .ascii ZINFO_TYPE_ADxW |
| .long pciheader_image_length |
| .long 512 |
| .long 0 |
| .ascii "ADHW" |
| .long pciheader_runtime_length |
| .long 512 |
| .long 0 |
| .previous |
| .endif /* PCIR */ |
| |
| /* PnP doesn't require any particular alignment, but IBM |
| * BIOSes will scan on 16-byte boundaries rather than using |
| * the offset stored at 0x1a |
| */ |
| .balign 16 |
| pnpheader: |
| .ascii "$PnP" /* Signature */ |
| .byte 0x01 /* Structure revision */ |
| .byte ( pnpheader_len / 16 ) /* Length (in 16 byte increments) */ |
| .word 0x0000 /* Offset of next header */ |
| .byte 0x00 /* Reserved */ |
| .byte 0x00 /* Checksum */ |
| .long 0x00000000 /* Device identifier */ |
| .word mfgstr /* Manufacturer string */ |
| .word prodstr /* Product name */ |
| .byte 0x02 /* Device base type code */ |
| .byte 0x00 /* Device sub-type code */ |
| .byte 0x00 /* Device interface type code */ |
| .byte 0xf4 /* Device indicator */ |
| .word 0x0000 /* Boot connection vector */ |
| .word 0x0000 /* Disconnect vector */ |
| .word bev_entry /* Boot execution vector */ |
| .word 0x0000 /* Reserved */ |
| .word 0x0000 /* Static resource information vector*/ |
| .equ pnpheader_len, . - pnpheader |
| .size pnpheader, . - pnpheader |
| |
| /* Manufacturer string */ |
| mfgstr: |
| .asciz "https://ipxe.org" |
| .size mfgstr, . - mfgstr |
| |
| /* Product string |
| * |
| * Defaults to PRODUCT_SHORT_NAME. If the ROM image is writable at |
| * initialisation time, it will be filled in to include the PCI |
| * bus:dev.fn number of the card as well. |
| */ |
| prodstr: |
| .ascii PRODUCT_SHORT_NAME |
| .ifeqs BUSTYPE, "PCIR" |
| prodstr_separator: |
| .byte 0 |
| .ascii "(PCI " |
| prodstr_pci_id: |
| .ascii "xx:xx.x)" /* Filled in by init code */ |
| .endif /* PCIR */ |
| .byte 0 |
| .size prodstr, . - prodstr |
| |
| .globl undiheader |
| .weak undiloader |
| .balign 4 |
| undiheader: |
| .ascii "UNDI" /* Signature */ |
| .byte undiheader_len /* Length of structure */ |
| .byte 0 /* Checksum */ |
| .byte 0 /* Structure revision */ |
| .byte 0,1,2 /* PXE version: 2.1.0 */ |
| .word undiloader /* Offset to loader routine */ |
| .word _data16_memsz /* Stack segment size */ |
| .word _data16_memsz /* Data segment size */ |
| .word _text16_memsz /* Code segment size */ |
| .ascii BUSTYPE /* Bus type */ |
| .equ undiheader_len, . - undiheader |
| .size undiheader, . - undiheader |
| |
| .balign 4 |
| ipxeheader: |
| .ascii "iPXE" /* Signature */ |
| .byte ipxeheader_len /* Length of structure */ |
| .byte 0 /* Checksum */ |
| shrunk_rom_size: |
| .byte 0 /* Shrunk size (in 512-byte blocks) */ |
| .byte 0 /* Reserved */ |
| build_id: |
| .long _build_id /* Randomly-generated build ID */ |
| .equ ipxeheader_len, . - ipxeheader |
| .size ipxeheader, . - ipxeheader |
| |
| .section ".zinfo.fixup", "a", @progbits /* Compressor fixups */ |
| .ascii "ADHB" |
| .long shrunk_rom_size |
| .long 512 |
| .long 0 |
| .previous |
| |
| /* Initialisation (called once during POST) |
| * |
| * Determine whether or not this is a PnP system via a signature |
| * check. If it is PnP, return to the PnP BIOS indicating that we are |
| * a boot-capable device; the BIOS will call our boot execution vector |
| * if it wants to boot us. If it is not PnP, hook INT 19. |
| */ |
| init: |
| /* Preserve registers, clear direction flag, set %ds=%cs */ |
| pushaw |
| pushw %ds |
| pushw %es |
| pushw %fs |
| pushw %gs |
| cld |
| pushw %cs |
| popw %ds |
| |
| /* Print message as early as possible */ |
| movw $init_message, %si |
| xorw %di, %di |
| call print_message |
| |
| /* Store PCI 3.0 runtime segment address for later use, if |
| * applicable. |
| */ |
| .ifeqs BUSTYPE, "PCIR" |
| movw %bx, %gs |
| .endif |
| |
| /* Store PCI bus:dev.fn address, print PCI bus:dev.fn, and add |
| * PCI bus:dev.fn to product name string, if applicable. |
| */ |
| .ifeqs BUSTYPE, "PCIR" |
| xorw %di, %di |
| call print_space |
| movw %ax, init_pci_busdevfn |
| call print_pci_busdevfn |
| movw $prodstr_pci_id, %di |
| call print_pci_busdevfn |
| movb $( ' ' ), prodstr_separator |
| .endif |
| |
| /* Print segment address */ |
| xorw %di, %di |
| call print_space |
| movw %cs, %ax |
| call print_hex_word |
| |
| /* Check for PCI BIOS version, if applicable */ |
| .ifeqs BUSTYPE, "PCIR" |
| pushl %ebx |
| pushl %edx |
| pushl %edi |
| stc |
| movw $0xb101, %ax |
| int $0x1a |
| jc no_pci3 |
| cmpl $PCI_SIGNATURE, %edx |
| jne no_pci3 |
| testb %ah, %ah |
| jnz no_pci3 |
| movw $init_message_pci, %si |
| xorw %di, %di |
| call print_message |
| movb %bh, %al |
| call print_hex_nibble |
| movb $( '.' ), %al |
| call print_character |
| movb %bl, %al |
| call print_hex_byte |
| cmpb $3, %bh |
| jb no_pci3 |
| /* PCI >=3.0: leave %gs as-is if sane */ |
| movw %gs, %ax |
| cmpw $0xa000, %ax /* Insane if %gs < 0xa000 */ |
| jb pci3_insane |
| movw %cs, %bx /* Sane if %cs == %gs */ |
| cmpw %bx, %ax |
| je 1f |
| movzbw romheader_size, %cx /* Sane if %cs+len <= %gs */ |
| shlw $5, %cx |
| addw %cx, %bx |
| cmpw %bx, %ax |
| jae 1f |
| movw %cs, %bx /* Sane if %gs+len <= %cs */ |
| addw %cx, %ax |
| cmpw %bx, %ax |
| jbe 1f |
| pci3_insane: /* PCI 3.0 with insane %gs value: print error and ignore %gs */ |
| movb $( '!' ), %al |
| call print_character |
| movw %gs, %ax |
| call print_hex_word |
| no_pci3: |
| /* PCI <3.0: set %gs (runtime segment) = %cs (init-time segment) */ |
| pushw %cs |
| popw %gs |
| 1: popl %edi |
| popl %edx |
| popl %ebx |
| .endif /* PCIR */ |
| |
| /* Check for PnP BIOS. Although %es:di should point to the |
| * PnP BIOS signature on entry, some BIOSes fail to do this. |
| */ |
| movw $( 0xf000 - 1 ), %bx |
| pnp_scan: |
| incw %bx |
| jz no_pnp |
| movw %bx, %es |
| cmpl $PNP_SIGNATURE, %es:0 |
| jne pnp_scan |
| xorw %dx, %dx |
| xorw %si, %si |
| movzbw %es:5, %cx |
| 1: es lodsb |
| addb %al, %dl |
| loop 1b |
| jnz pnp_scan |
| /* Is PnP: print PnP message */ |
| movw $init_message_pnp, %si |
| xorw %di, %di |
| call print_message |
| jmp pnp_done |
| no_pnp: /* Not PnP-compliant - hook INT 19 */ |
| #ifdef NONPNP_HOOK_INT19 |
| movw $init_message_int19, %si |
| xorw %di, %di |
| call print_message |
| xorw %ax, %ax |
| movw %ax, %es |
| pushl %es:( 0x19 * 4 ) |
| popl orig_int19 |
| pushw %gs /* %gs contains runtime %cs */ |
| pushw $int19_entry |
| popl %es:( 0x19 * 4 ) |
| #endif /* NONPNP_HOOK_INT19 */ |
| pnp_done: |
| |
| /* Check for PMM */ |
| movw $( 0xe000 - 1 ), %bx |
| pmm_scan: |
| incw %bx |
| jz no_pmm |
| movw %bx, %es |
| cmpl $PMM_SIGNATURE, %es:0 |
| jne pmm_scan |
| xorw %dx, %dx |
| xorw %si, %si |
| movzbw %es:5, %cx |
| 1: es lodsb |
| addb %al, %dl |
| loop 1b |
| jnz pmm_scan |
| /* PMM found: print PMM message */ |
| movw $init_message_pmm, %si |
| xorw %di, %di |
| call print_message |
| /* We have PMM and so a 1kB stack: preserve whole registers */ |
| pushal |
| /* Allocate image source PMM block. Round up the size to the |
| * nearest 4kB (8 512-byte sectors) to work around AMI BIOS bugs. |
| */ |
| movzbl romheader_size, %ecx |
| addw extra_size, %cx |
| addw $0x0007, %cx /* Round up to multiple of 8 512-byte sectors */ |
| andw $0xfff8, %cx |
| shll $5, %ecx |
| movl $PMM_HANDLE_BASE_IMAGE_SOURCE, %ebx |
| movw $get_pmm_image_source, %bp |
| call get_pmm |
| movl %esi, image_source |
| jz 1f |
| /* Copy ROM to image source PMM block */ |
| pushw %es |
| xorw %ax, %ax |
| movw %ax, %es |
| movl %esi, %edi |
| xorl %esi, %esi |
| movzbl romheader_size, %ecx |
| shll $7, %ecx |
| addr32 rep movsl /* PMM presence implies flat real mode */ |
| popw %es |
| /* Shrink ROM */ |
| movb shrunk_rom_size, %al |
| movb %al, romheader_size |
| 1: /* Allocate decompression PMM block. Allow 4kB for page |
| * alignment and round up the size to the nearest 128kB, then |
| * use the size within the PMM handle; this allows the same |
| * decompression area to be shared between multiple iPXE ROMs |
| * even with differing build IDs |
| */ |
| movl $_textdata_memsz_pgh, %ecx |
| addl $( 0x00000100 /* 4kB */ + 0x00001fff /* 128kB - 1 */ ), %ecx |
| andl $( 0xffffe000 /* ~( 128kB - 1 ) */ ), %ecx |
| movl %ecx, %ebx |
| shrw $12, %bx |
| orl $PMM_HANDLE_BASE_DECOMPRESS_TO, %ebx |
| movw $get_pmm_decompress_to, %bp |
| call get_pmm |
| addl $( 0x00000fff /* 4kB - 1 */ ), %esi |
| andl $( 0xfffff000 /* ~( 4kB - 1 ) */ ), %esi |
| movl %esi, decompress_to |
| /* Restore registers */ |
| popal |
| no_pmm: |
| |
| /* Update checksum */ |
| xorw %bx, %bx |
| xorw %si, %si |
| movzbw romheader_size, %cx |
| shlw $9, %cx |
| 1: lodsb |
| addb %al, %bl |
| loop 1b |
| subb %bl, checksum |
| |
| /* Copy self to option ROM space, if applicable. Required for |
| * PCI3.0, which loads us to a temporary location in low |
| * memory. Will be a no-op for lower PCI versions. |
| */ |
| .ifeqs BUSTYPE, "PCIR" |
| /* Get runtime segment address and length */ |
| movw %gs, %ax |
| movw %ax, %es |
| movzbw romheader_size, %cx |
| /* Print runtime segment address */ |
| xorw %di, %di |
| call print_space |
| call print_hex_word |
| /* Fail if we have insufficient space in final location */ |
| movw %cs, %si |
| cmpw %si, %ax |
| je 1f |
| cmpw pciheader_runtime_length, %cx |
| jbe 1f |
| movb $( '!' ), %al |
| call print_character |
| xorw %cx, %cx |
| 1: /* Copy to final location */ |
| shlw $9, %cx |
| xorw %si, %si |
| xorw %di, %di |
| cs rep movsb |
| .endif |
| |
| /* Skip prompt if this is not the first PCI function, if applicable */ |
| .ifeqs BUSTYPE, "PCIR" |
| testb $PCI_FUNC_MASK, init_pci_busdevfn |
| jnz no_shell |
| .endif |
| /* Prompt for POST-time shell */ |
| movw $init_message_prompt, %si |
| xorw %di, %di |
| call print_message |
| movw $prodstr, %si |
| call print_message |
| movw $init_message_dots, %si |
| call print_message |
| /* Wait for Ctrl-B */ |
| movw $0xff02, %bx |
| call wait_for_key |
| /* Clear prompt */ |
| pushf |
| xorw %di, %di |
| call print_kill_line |
| movw $init_message_done, %si |
| call print_message |
| popf |
| jnz no_shell |
| /* Ctrl-B was pressed: invoke iPXE. The keypress will be |
| * picked up by the initial shell prompt, and we will drop |
| * into a shell. |
| */ |
| xorl %ebp, %ebp /* Inhibit use of INT 15,e820 and INT 15,e801 */ |
| pushw %cs |
| call exec |
| no_shell: |
| movb $( '\n' ), %al |
| xorw %di, %di |
| call print_character |
| |
| /* Restore registers */ |
| popw %gs |
| popw %fs |
| popw %es |
| popw %ds |
| popaw |
| |
| /* Indicate boot capability to PnP BIOS, if present */ |
| movw $0x20, %ax |
| lret |
| .size init, . - init |
| |
| /* Attempt to find or allocate PMM block |
| * |
| * Parameters: |
| * %ecx : size of block to allocate, in paragraphs |
| * %ebx : PMM handle base |
| * %bp : routine to check acceptability of found blocks |
| * %es:0000 : PMM structure |
| * Returns: |
| * %ebx : PMM handle |
| * %esi : allocated block address, or zero (with ZF set) if allocation failed |
| */ |
| get_pmm: |
| /* Preserve registers */ |
| pushl %eax |
| pushw %di |
| movw $( ' ' ), %di |
| get_pmm_find: |
| /* Try to find existing block */ |
| pushl %ebx /* PMM handle */ |
| pushw $PMM_FIND |
| lcall *%es:7 |
| addw $6, %sp |
| pushw %dx |
| pushw %ax |
| popl %esi |
| /* Treat 0xffffffff (not supported) as 0x00000000 (not found) */ |
| incl %esi |
| jz get_pmm_allocate |
| decl %esi |
| jz get_pmm_allocate |
| /* Block found - check acceptability */ |
| call *%bp |
| jnc get_pmm_done |
| /* Block not acceptable - increment handle and retry */ |
| incl %ebx |
| jmp get_pmm_find |
| get_pmm_allocate: |
| /* Block not found - try to allocate new block */ |
| pushw $0x0002 /* Extended memory */ |
| pushl %ebx /* PMM handle */ |
| pushl %ecx /* Length */ |
| pushw $PMM_ALLOCATE |
| lcall *%es:7 |
| addw $12, %sp |
| pushw %dx |
| pushw %ax |
| popl %esi |
| movw $( '+' ), %di /* Indicate allocation attempt */ |
| get_pmm_done: |
| /* Print block address */ |
| movw %di, %ax |
| xorw %di, %di |
| call print_character |
| movl %esi, %eax |
| call print_hex_dword |
| /* Treat 0xffffffff (not supported) as 0x00000000 (allocation |
| * failed), and set ZF to indicate a zero result. |
| */ |
| incl %esi |
| jz 1f |
| decl %esi |
| 1: /* Restore registers and return */ |
| popw %di |
| popl %eax |
| ret |
| .size get_pmm, . - get_pmm |
| |
| /* Check acceptability of image source block */ |
| get_pmm_image_source: |
| pushw %es |
| xorw %ax, %ax |
| movw %ax, %es |
| movl build_id, %eax |
| addr32 cmpl %es:build_id(%esi), %eax |
| je 1f |
| stc |
| 1: popw %es |
| ret |
| .size get_pmm_image_source, . - get_pmm_image_source |
| |
| /* Check acceptability of decompression block */ |
| get_pmm_decompress_to: |
| clc |
| ret |
| .size get_pmm_decompress_to, . - get_pmm_decompress_to |
| |
| /* |
| * Note to hardware vendors: |
| * |
| * If you wish to brand this boot ROM, please do so by defining the |
| * strings PRODUCT_NAME and PRODUCT_SHORT_NAME in config/branding.h. |
| * |
| * While nothing in the GPL prevents you from removing all references |
| * to iPXE or https://ipxe.org, we prefer you not to do so. |
| * |
| * If you have an OEM-mandated branding requirement that cannot be |
| * satisfied simply by defining PRODUCT_NAME and PRODUCT_SHORT_NAME, |
| * please contact us. |
| * |
| * [ Including an ASCII NUL in PRODUCT_NAME is considered to be |
| * bypassing the spirit of this request! ] |
| */ |
| init_message: |
| .ascii "\n" |
| .ascii PRODUCT_NAME |
| .ascii "\n" |
| .ascii PRODUCT_SHORT_NAME |
| .ascii " (" |
| .ascii PRODUCT_URI |
| .asciz ")" |
| .size init_message, . - init_message |
| .ifeqs BUSTYPE, "PCIR" |
| init_message_pci: |
| .asciz " PCI" |
| .size init_message_pci, . - init_message_pci |
| .endif /* PCIR */ |
| init_message_pnp: |
| .asciz " PnP" |
| .size init_message_pnp, . - init_message_pnp |
| init_message_pmm: |
| .asciz " PMM" |
| .size init_message_pmm, . - init_message_pmm |
| init_message_int19: |
| .asciz " INT19" |
| .size init_message_int19, . - init_message_int19 |
| init_message_prompt: |
| .asciz "\nPress Ctrl-B to configure " |
| .size init_message_prompt, . - init_message_prompt |
| init_message_dots: |
| .asciz "..." |
| .size init_message_dots, . - init_message_dots |
| init_message_done: |
| .asciz "\n\n" |
| .size init_message_done, . - init_message_done |
| |
| /* PCI bus:dev.fn |
| * |
| */ |
| .ifeqs BUSTYPE, "PCIR" |
| init_pci_busdevfn: |
| .word 0 |
| .size init_pci_busdevfn, . - init_pci_busdevfn |
| .endif /* PCIR */ |
| |
| /* Image source area |
| * |
| * May be either zero (indicating to use option ROM space as source), |
| * or within a PMM-allocated block. |
| */ |
| .globl image_source |
| image_source: |
| .long 0 |
| .size image_source, . - image_source |
| |
| /* Additional image source size (in 512-byte sectors) |
| * |
| */ |
| extra_size: |
| .word 0 |
| .size extra_size, . - extra_size |
| |
| /* Temporary decompression area |
| * |
| * May be either zero (indicating to use default decompression area in |
| * high memory), or within a PMM-allocated block. |
| */ |
| .globl decompress_to |
| decompress_to: |
| .long 0 |
| .size decompress_to, . - decompress_to |
| |
| /* Boot Execution Vector entry point |
| * |
| * Called by the PnP BIOS when it wants to boot us. |
| */ |
| bev_entry: |
| orl $0xffffffff, %ebp /* Allow arbitrary relocation */ |
| pushw %cs |
| call exec |
| lret |
| .size bev_entry, . - bev_entry |
| |
| /* INT19 entry point |
| * |
| * Called via the hooked INT 19 if we detected a non-PnP BIOS. We |
| * attempt to return via the original INT 19 vector (if we were able |
| * to store it). |
| */ |
| int19_entry: |
| pushw %cs |
| popw %ds |
| /* Prompt user to press B to boot */ |
| movw $int19_message_prompt, %si |
| xorw %di, %di |
| call print_message |
| movw $prodstr, %si |
| call print_message |
| movw $int19_message_dots, %si |
| call print_message |
| movw $0xdf4e, %bx |
| call wait_for_key |
| pushf |
| xorw %di, %di |
| call print_kill_line |
| movw $int19_message_done, %si |
| call print_message |
| popf |
| jz 1f |
| /* Leave keypress in buffer and start iPXE. The keypress will |
| * cause the usual initial Ctrl-B prompt to be skipped. |
| */ |
| orl $0xffffffff, %ebp /* Allow arbitrary relocation */ |
| pushw %cs |
| call exec |
| 1: /* Try to call original INT 19 vector */ |
| movl %cs:orig_int19, %eax |
| testl %eax, %eax |
| je 2f |
| ljmp *%cs:orig_int19 |
| 2: /* No chained vector: issue INT 18 as a last resort */ |
| int $0x18 |
| .size int19_entry, . - int19_entry |
| orig_int19: |
| .long 0 |
| .size orig_int19, . - orig_int19 |
| |
| int19_message_prompt: |
| .asciz "Press N to skip booting from " |
| .size int19_message_prompt, . - int19_message_prompt |
| int19_message_dots: |
| .asciz "..." |
| .size int19_message_dots, . - int19_message_dots |
| int19_message_done: |
| .asciz "\n\n" |
| .size int19_message_done, . - int19_message_done |
| |
| /* Execute as a boot device |
| * |
| */ |
| exec: /* Set %ds = %cs */ |
| pushw %cs |
| popw %ds |
| |
| /* Print message as soon as possible */ |
| movw $prodstr, %si |
| xorw %di, %di |
| call print_message |
| movw $exec_message_pre_install, %si |
| call print_message |
| |
| /* Store magic word on BIOS stack and remember BIOS %ss:sp */ |
| pushl $STACK_MAGIC |
| movw %ss, %cx |
| movw %sp, %dx |
| |
| /* Obtain a reasonably-sized temporary stack */ |
| xorw %bx, %bx |
| movw %bx, %ss |
| movw $0x7c00, %sp |
| |
| /* Install iPXE */ |
| call alloc_basemem |
| movl image_source, %esi |
| movl decompress_to, %edi |
| call install_prealloc |
| |
| /* Print message indicating successful installation */ |
| movw $exec_message_post_install, %si |
| xorw %di, %di |
| call print_message |
| |
| /* Set up real-mode stack */ |
| movw %bx, %ss |
| movw $_estack16, %sp |
| |
| /* Jump to .text16 segment */ |
| pushw %ax |
| pushw $1f |
| lret |
| .section ".text16", "awx", @progbits |
| 1: |
| /* Retrieve PCI bus:dev.fn, if applicable */ |
| .ifeqs BUSTYPE, "PCIR" |
| movw init_pci_busdevfn, %ax |
| .endif |
| |
| /* Set up %ds for access to .data16 */ |
| movw %bx, %ds |
| |
| /* Store PCI bus:dev.fn, if applicable */ |
| .ifeqs BUSTYPE, "PCIR" |
| #ifdef AUTOBOOT_ROM_FILTER |
| movw %ax, autoboot_busdevfn |
| #endif /* AUTOBOOT_ROM_FILTER */ |
| .endif |
| |
| /* Run iPXE */ |
| virtcall main |
| |
| /* Set up flat real mode for return to BIOS */ |
| call flatten_real_mode |
| |
| /* Uninstall iPXE */ |
| call uninstall |
| |
| /* Restore BIOS stack */ |
| movw %cx, %ss |
| movw %dx, %sp |
| |
| /* Check magic word on BIOS stack */ |
| popl %eax |
| cmpl $STACK_MAGIC, %eax |
| jne 1f |
| /* BIOS stack OK: return to caller */ |
| lret |
| 1: /* BIOS stack corrupt: use INT 18 */ |
| int $0x18 |
| .previous |
| |
| exec_message_pre_install: |
| .asciz " starting execution..." |
| .size exec_message_pre_install, . - exec_message_pre_install |
| exec_message_post_install: |
| .asciz "ok\n" |
| .size exec_message_post_install, . - exec_message_post_install |
| |
| /* Wait for key press specified by %bl (masked by %bh) |
| * |
| * Used by init and INT19 code when prompting user. If the specified |
| * key is pressed, it is left in the keyboard buffer. |
| * |
| * Returns with ZF set iff specified key is pressed. |
| */ |
| wait_for_key: |
| /* Preserve registers */ |
| pushw %cx |
| pushw %ax |
| 1: /* Empty the keyboard buffer before waiting for input */ |
| movb $0x01, %ah |
| int $0x16 |
| jz 2f |
| xorw %ax, %ax |
| int $0x16 |
| jmp 1b |
| 2: /* Wait for a key press */ |
| movw $ROM_BANNER_TIMEOUT_TICKS, %cx |
| 3: decw %cx |
| js 99f /* Exit with ZF clear */ |
| /* Wait for timer tick to be updated */ |
| call wait_for_tick |
| /* Check to see if a key was pressed */ |
| movb $0x01, %ah |
| int $0x16 |
| jz 3b |
| /* Check to see if key was the specified key */ |
| andb %bh, %al |
| cmpb %al, %bl |
| je 99f /* Exit with ZF set */ |
| /* Not the specified key: remove from buffer and stop waiting */ |
| pushfw |
| xorw %ax, %ax |
| int $0x16 |
| popfw /* Exit with ZF clear */ |
| 99: /* Restore registers and return */ |
| popw %ax |
| popw %cx |
| ret |
| .size wait_for_key, . - wait_for_key |
| |
| /* Wait for timer tick |
| * |
| * Used by wait_for_key |
| */ |
| wait_for_tick: |
| pushl %eax |
| pushw %fs |
| movw $0x40, %ax |
| movw %ax, %fs |
| movl %fs:(0x6c), %eax |
| 1: pushf |
| sti |
| hlt |
| popf |
| cmpl %fs:(0x6c), %eax |
| je 1b |
| popw %fs |
| popl %eax |
| ret |
| .size wait_for_tick, . - wait_for_tick |
| |
| /* Drag in objects via _rom_start */ |
| REQUIRING_SYMBOL ( _rom_start ) |
| |
| /* Drag in ROM configuration */ |
| REQUIRE_OBJECT ( config_romprefix ) |
