diff options
Diffstat (limited to 'qemu/roms/ipxe/src/arch/i386/prefix/romprefix.S')
| -rw-r--r-- | qemu/roms/ipxe/src/arch/i386/prefix/romprefix.S | 895 |
1 files changed, 0 insertions, 895 deletions
diff --git a/qemu/roms/ipxe/src/arch/i386/prefix/romprefix.S b/qemu/roms/ipxe/src/arch/i386/prefix/romprefix.S deleted file mode 100644 index 18dda2b37..000000000 --- a/qemu/roms/ipxe/src/arch/i386/prefix/romprefix.S +++ /dev/null @@ -1,895 +0,0 @@ -/* 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 <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 - - .text - .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" -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 0x02, 0x00, 0x00 /* 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 ZINFO_TYPE_ADxW - .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 - */ - .align 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 "http://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 -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 - -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. Round up the size to the - * nearest 128kB and 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 $0x00001fff, %ecx - andl $0xffffe000, %ecx - movl %ecx, %ebx - shrw $12, %bx - orl $PMM_HANDLE_BASE_DECOMPRESS_TO, %ebx - movw $get_pmm_decompress_to, %bp - call get_pmm - 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" - xorw %di, %di - call print_space - movw %gs, %ax - call print_hex_word - movzbw romheader_size, %cx - shlw $9, %cx - movw %ax, %es - 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 http://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 - - /* Call main() */ - pushl $main - pushw %cs - call prot_call - popl %eax /* discard */ - - /* 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 ) |