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Diffstat (limited to 'arch/x86/boot/boot_hdisk.S')
| -rw-r--r-- | arch/x86/boot/boot_hdisk.S | 170 |
1 files changed, 0 insertions, 170 deletions
diff --git a/arch/x86/boot/boot_hdisk.S b/arch/x86/boot/boot_hdisk.S deleted file mode 100644 index 6f98197512..0000000000 --- a/arch/x86/boot/boot_hdisk.S +++ /dev/null @@ -1,170 +0,0 @@ -/* - * Copyright (C) 2009 Juergen Beisert, Pengutronix - * - * This code was inspired by the GRUB2 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. - * - * - */ - -/** - * @file - * @brief Loading the barebox image from a disk drive in LBA mode - */ - -/** - * @fn void real_start(void) - * @brief A very simple and small loader to fetch all required sectors - * from the boot media. - */ - - - .file "boot_hdisk.S" - .code16 - - /* - * These symbols are generated by the linker, because they need a - * special layout. This layout is needed to be able to setup this - * bootloader by patching the binary when it gets stored into the - * master boot record. - */ - .extern indirect_sector_lba - .extern boot_stack - .extern start_pre_uboot - .extern boot_disk - .section .boot_code, "ax" - - .globl real_start - .type real_start, @function - -real_start: - - xorw %ax, %ax /* set up %ds and %ss as offset from 0 */ - movw %ax, %ds - movw %ax, %ss - - /* set up the REAL stack */ - movw $boot_stack, %sp - - sti /* we're safe again */ - - /* save drive reference first thing! */ - movb %dl, boot_disk - pushw %dx - - movw $notification_string, %si - call output_message - - /* - * This boot code only supports LBA. We fail here, if the BIOS - * does not support LBA for the harddisk - */ - - /* check if LBA is supported */ - movb $0x41, %ah - movw $0x55aa, %bx - int $0x13 - - /* - * %dl may have been clobbered by INT 13, AH=41H. - * This happens, for example, with AST BIOS 1.04. - */ - popw %dx - pushw %dx - - /* stop if no LBA support */ - jc no_lba - cmpw $0xaa55, %bx - jne no_lba - andw $1, %cx - jz no_lba - -lba_mode: - /* - * Load the indirect sector. Its content is ready for use, - * provided by the installer - */ - movw $indirect_sector_lba, %si - movb $0x42, %ah - int $0x13 - jc no_lba /* error? Then die */ - - /* - * Now loop through all valid entries in the indirect sector - */ - movw $indirect_area, %si - -load_loop: - /* - * Stop if this "Disk Address Packet Structure" is invalid - * We call it invalid, if the size member is zero. If it is invalid - * we are optimistic and calling the loaded image - */ - movw (%si), %ax - cmpw $0x0000, %ax - je start_main - - /* - * Load this entry - */ - movb $0x42, %ah - int $0x13 - jc no_lba - - addw (%si), %si /* next entry */ - cmpw $indirect_area + 512, %si - jne load_loop - /* - * fall through to start u-boot. - */ -start_main: - movw $jmp_string, %si - call output_message - jmp start_pre_uboot -/* - * die if there is no LBA support - */ -no_lba: movw $chs_string, %si - call output_message - hlt - -/* - * message: write the string pointed to by %si - * - * WARNING: trashes %si, %ax, and %bx - */ - -/* - * Use BIOS "int 10H Function 0Eh" to write character in teletype mode - * %ah = 0xe %al = character - * %bh = page %bl = foreground color (graphics modes) - */ - -1: - movw $0x0001, %bx - movb $0xe, %ah - int $0x10 /* display this char */ - -output_message: - lodsb - cmpb $0, %al - jne 1b /* if not end of string, next char */ - ret - -/* ---------------------------------------------------------------------- */ - - .section .boot_data - -notification_string: .asciz "BAREBOX " -chs_string: .asciz "CHS " -jmp_string: .asciz "JMP " - |