; Definitions for use in GeekOS boot code ; Copyright (c) 2001, David H. Hovemeyer ; $Revision: 1.12 $ ; This is free software. You are permitted to use, ; redistribute, and modify it as specified in the file "COPYING". ; A lot of this code is adapted from Kernel Toolkit 0.2 ; and Linux version 2.2.x, so the following copyrights apply: ; Copyright (C) 1991, 1992 Linus Torvalds ; modified by Drew Eckhardt ; modified by Bruce Evans (bde) ; adapted for Kernel Toolkit by Luigi Sgro %ifndef DEFS_ASM %define DEFS_ASM ;Zheng 08/01/2008 SYSSEG equ 0x1000 COMMAND_LINE_SIZE equ 1024 SETUPSECTS equ 4 ; /* default nr of setup-sectors */ SYSSIZE equ 0x7f00 ; /* system size: # of 16-byte clicks */ ROOT_DEV equ 0 ; /* ROOT_DEV is now written by "build" */ SWAP_DEV equ 0 ; /* SWAP_DEV is now written by "build" */ ;VM_KERNEL_TARGET equ 0x100000 ; BIOS loads the boot sector at offset 0 in this segment BOOTSEG equ 0x07C0 ; We'll move the boot sector up to higher memory. ; Note that the "ISA hole" begins at segment 0xA000 == 640K. INITSEG equ 0x9000 ; Put the setup code here, just after the boot sector. SETUPSEG equ 0x9020 ; Load our "Kernel" at this segment, which starts at 64K. ; The number of sectors in the kernel, NUM_KERN_SECTORS, ; will be passed on the command line. KERNSEG equ 0x1000 ;; Load Segment for moving guest kernel to extended memory ;; Note that this segment must not colide with where the VMM kernel ;; is initially loaded. At this point, we just place it in the last ;; 64K of RAM available before the ISA hole and hope for the best VMSEG equ 0x8000 ; Size of PFAT boot record. ; Keep up to date with . PFAT_BOOT_RECORD_SIZE equ 28 ; Offset of BIOS signature word in boot sector. BIOS_SIGNATURE_OFFSET equ 510 ; Offset of PFAT boot record in boot sector. PFAT_BOOT_RECORD_OFFSET equ BIOS_SIGNATURE_OFFSET - PFAT_BOOT_RECORD_SIZE ; Video memory segment VIDSEG equ 0xb800 ; The following information is correct for a 1.44M floppy. ; Yes, I'm hard coding this. ;SECTORS_PER_TRACK equ 18 HEADS equ 2 CYLINDERS equ 80 ; 8259A PIC initialization codes. ; Source: Linux bootsect.S, and Intel 8259A datasheet ; The most important reason why we reprogram the PICs is to ; route the hardware interrupts through vectors *above* ; those reserved by Intel. The BIOS (for historical reasons :-) ; routes them such that they conflict with internal processor-generated ; interrupts. ICW1 equ 0x11 ; ICW1 - ICW4 needed, cascade mode, interval=8, ; edge triggered. (I think interval is irrelevant ; for x86.) ICW2_MASTER equ 0x20 ; put IRQs 0-7 at 0x20 (above Intel reserved ints) ICW2_SLAVE equ 0x28 ; put IRQs 8-15 at 0x28 ICW3_MASTER equ 0x04 ; IR2 connected to slave ICW3_SLAVE equ 0x02 ; slave has id 2 ICW4 equ 0x01 ; 8086 mode, no auto-EOI, non-buffered mode, ; not special fully nested mode ; Kernel code and data segment selectors. ; Keep these up to date with defs.h. KERNEL_CS equ 1<<3 ; kernel code segment is GDT entry 1 KERNEL_DS equ 2<<3 ; kernel data segment is GDT entry 2 ; Pages for context object and stack for initial kernel thread - ; the one we construct for Main(). Keep these up to date with defs.h. ; We put them at 1MB, for no particular reason. ;; Moved to just after where the VM will go KERN_THREAD_OBJ equ 4096 KERN_STACK equ KERN_THREAD_OBJ + 4096 %endif