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 * @(#)start.s 7.4 (Berkeley) 10/11/92 11 * 12 * start.s - 13 * 14 * Contains code that is the first executed at boot time. 15 * 16 * Copyright (C) 1989 Digital Equipment Corporation. 17 * Permission to use, copy, modify, and distribute this software and 18 * its documentation for any purpose and without fee is hereby granted, 19 * provided that the above copyright notice appears in all copies. 20 * Digital Equipment Corporation makes no representations about the 21 * suitability of this software for any purpose. It is provided "as is" 22 * without express or implied warranty. 23 * 24 * from: $Header: /sprite/src/boot/decprom/ds3100.md/RCS/start.s, 25 * v 1.1 90/02/16 16:19:39 shirriff Exp $ SPRITE (DECWRL) 26 */ 27 28#include <machine/regdef.h> 29#include <machine/machConst.h> 30 31/* 32 * Amount to take off of the stack for the benefit of the debugger. 33 */ 34#define START_FRAME ((4 * 4) + 4 + 4) 35#define Init 0xbfc00018 36 37 .globl start 38start: 39 .set noreorder 40 mtc0 zero, MACH_COP_0_STATUS_REG # Disable interrupts 41 li sp, MACH_CODE_START - START_FRAME 42 la gp, _gp 43 sw zero, START_FRAME - 4(sp) # Zero out old ra for debugger 44 sw zero, START_FRAME - 8(sp) # Zero out old fp for debugger 45 jal main # main(argc, argv, envp) 46 nop 47 li a0, Init # done, so call prom 48 j a0 49 50/* dummy routine for gcc2 */ 51 .globl __main 52__main: 53 j ra 54 nop 55 56 .globl Boot_Transfer 57Boot_Transfer: 58 mtc0 zero, MACH_COP_0_STATUS_REG # Disable interrupts 59 li sp, MACH_CODE_START - START_FRAME 60 la gp, _gp 61 sw zero, START_FRAME - 4(sp) # Zero out old ra for debugger 62 sw zero, START_FRAME - 8(sp) # Zero out old fp for debugger 63 jal a3 # Jump to routine 64 nop 65