1 /* 2 * Copyright (c) 1992 Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Ralph Campbell. 7 * 8 * %sccs.include.redist.c% 9 * 10 * @(#)dec_boot.h 7.2 (Berkeley) 04/19/92 11 * 12 * devDiskLabel.h -- 13 * 14 * This defines the disk label that Sun writes on the 0'th sector of 15 * the 0'th cylinder of its SMD disks. The disk label contains some 16 * geometry information and also the division of the disk into a 17 * number of partitions. Each partition is identified to the drive 18 * by a different unit number. 19 * 20 * from: $Header: /sprite/src/kernel/dev/RCS/devDiskLabel.h, 21 * v 9.4 90/03/01 12:22:36 jhh Exp $ SPRITE (Berkeley) 22 */ 23 24 /* 25 * Boot block information on the 0th sector. 26 * The boot program is stored in sequences of contiguous blocks. 27 * If mode is 0, there is just one sequence of blocks and one Dec_BootMap 28 * is used. If mode is 1, there are multiple sequences of blocks 29 * and multiple Dec_BootMaps are used, the last with numBlocks = 0. 30 * 31 * NOTE: The standard disk label offset is 64 which is 32 * after the boot information expected by the PROM boot loader. 33 */ 34 35 struct Dec_BootMap { 36 int numBlocks; /* Number of blocks to read. */ 37 int startBlock; /* Starting block on disk. */ 38 }; 39 40 struct Dec_DiskBoot { 41 char pad[8]; 42 int magic; /* DEC_BOOT_MAGIC */ 43 int mode; /* Mode for boot info. */ 44 int loadAddr; /* Address to start loading. */ 45 int execAddr; /* Address to start execing. */ 46 struct Dec_BootMap map[61]; /* boot program sections. */ 47 }; 48 49 #define DEC_BOOT_MAGIC 0x02757a 50 #define DEC_BOOT_SECTOR 0 51