patch-1.3.94 linux/arch/m68k/boot/amiga/bootstrap.c

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diff -u --recursive --new-file v1.3.93/linux/arch/m68k/boot/amiga/bootstrap.c linux/arch/m68k/boot/amiga/bootstrap.c
@@ -0,0 +1,782 @@
+/*
+** bootstrap.c -- This program loads the Linux/68k kernel into an Amiga
+**                and and launches it.
+**
+** Copyright 1993,1994 by Hamish Macdonald, Greg Harp
+**
+** Modified 11-May-94 by Geert Uytterhoeven
+**                      (Geert.Uytterhoeven@cs.kuleuven.ac.be)
+**     - A3640 MapROM check
+** Modified 31-May-94 by Geert Uytterhoeven
+**     - Memory thrash problem solved
+** Modified 07-March-95 by Geert Uytterhoeven
+**     - Memory block sizes are rounded to a multiple of 256K instead of 1M
+**       This _requires_ >0.9pl5 to work!
+**       (unless all block sizes are multiples of 1M :-)
+**
+** This file is subject to the terms and conditions of the GNU General Public
+** License.  See the file README.legal in the main directory of this archive
+** for more details.
+**
+*/
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/file.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+/* Amiga bootstrap include file */
+#include "bootstrap.h"
+
+/* required Linux/68k include files */
+#include <linux/a.out.h>
+#include <asm/bootinfo.h>
+
+/* temporary stack size */
+#define TEMP_STACKSIZE	256
+
+/* Exec Base */
+extern struct ExecBase *SysBase;
+
+extern char *optarg;
+
+struct exec kexec;
+char *memptr;
+u_long start_mem;
+u_long mem_size;
+u_long rd_size;
+
+struct ExpansionBase *ExpansionBase;
+struct GfxBase *GfxBase;
+
+struct bootinfo bi;
+u_long bi_size = sizeof bi;
+
+caddr_t CustomBase = (caddr_t)CUSTOM_PHYSADDR;
+
+void usage(void)
+{
+	fprintf (stderr, "Usage:\n"
+		 "\tbootstrap [-d] [-k kernel_executable] [-r ramdisk_file]"
+		 " [option...]\n");
+	exit (EXIT_FAILURE);
+}
+
+/*
+ * This assembler code is copied to chip ram, and
+ * then executed.
+ * It copies the kernel (and ramdisk) to their
+ * final resting place.
+ */
+#ifndef __GNUC__
+#error GNU CC is required to compile the bootstrap program
+#endif
+asm("
+.text
+.globl _copyall, _copyallend
+_copyall:
+				| /* put variables in registers because they may */
+	lea	_kexec,a3	| /* be overwritten by kernel/ramdisk copy!! - G.U. */
+	movel	_memptr,a4
+	movel	_start_mem,a5
+	movel	_mem_size,d0
+	movel	_rd_size,d1
+	movel	_bi_size,d5
+	movel	a3@(4),d2	| kexec.a_text
+	movel	a3@(8),d3	| kexec.a_data
+	movel	a3@(12),d4	| kexec.a_bss
+
+				| /* copy kernel text and data */
+	movel	a4,a0		| src = (u_long *)memptr;
+	movel	a0,a2		| limit = (u_long *)(memptr + kexec.a_text + kexec.a_data);
+	addl	d2,a2
+	addl	d3,a2
+	movel	a5,a1		| dest = (u_long *)start_mem;
+1:	cmpl	a0,a2
+	beqs	2f		| while (src < limit)
+	moveb	a0@+,a1@+	|	*dest++ = *src++;
+	bras	1b
+2:
+
+				| /* clear kernel bss */
+	movel	a1,a0		| dest = (u_long *)(start_mem + kexec.a_text + kexec.a_data);
+	movel	a1,a2		| limit = dest + kexec.a_bss / sizeof(u_long);
+	addl	d4,a2
+1:	cmpl	a0,a2
+	beqs	2f		| while (dest < limit)
+	clrb	a0@+		|	*dest++ = 0;
+	bras	1b
+2:
+
+				| /* copy bootinfo to end of bss */
+	movel	a4,a1		| src = (u long *)memptr + kexec.a_text + kexec.a_data);
+	addl	d2,a1
+	addl	d3,a1		| dest = end of bss (already in a0)
+	movel   d5,d7		| count = sizeof bi
+	subql	#1,d7
+1:	moveb	a1@+,a0@+	| while (--count > -1)
+	dbra	d7,1b		|	*dest++ = *src++
+	
+
+				| /* copy the ramdisk to the top of memory (from back to front) */
+	movel	a5,a1		| dest = (u_long *)(start_mem + mem_size);
+	addl	d0,a1
+	movel	a4,a2		| limit = (u_long *)(memptr + kexec.a_text + kexec.a_data + sizeof bi);
+	addl	d2,a2
+	addl	d3,a2
+        addl    d5,a2
+	movel	a2,a0		| src = (u_long *)((u_long)limit + rd_size);
+	addl	d1,a0
+1:	cmpl	a0,a2
+	beqs	2f		| while (src > limit)
+	moveb	a0@-,a1@-	| 	*--dest = *--src;
+	bras	1b
+2:
+				| /* jump to start of kernel */
+	movel	a5,a0		| jump_to (START_MEM);
+	jsr	a0@
+_copyallend:
+");
+
+asm("
+.text
+.globl _maprommed
+_maprommed:
+	oriw	#0x0700,sr
+	moveml	#0x3f20,sp@-
+/* Save cache settings */
+	.long 	0x4e7a1002	/* movec cacr,d1 */
+/* Save MMU settings */
+	.long 	0x4e7a2003	/* movec tc,d2 */
+	.long 	0x4e7a3004	/* movec itt0,d3 */
+	.long 	0x4e7a4005	/* movec itt1,d4 */
+	.long 	0x4e7a5006	/* movec dtt0,d5 */
+	.long 	0x4e7a6007	/* movec dtt1,d6 */
+	moveq	#0,d0
+	movel	d0,a2
+/* Disable caches */
+	.long 	0x4e7b0002	/* movec d0,cacr */
+/* Disable MMU */
+	.long 	0x4e7b0003	/* movec d0,tc */
+	.long 	0x4e7b0004	/* movec d0,itt0 */
+	.long 	0x4e7b0005	/* movec d0,itt1 */
+	.long 	0x4e7b0006	/* movec d0,dtt0 */
+	.long 	0x4e7b0007	/* movec d0,dtt1 */
+	lea	0x07f80000,a0
+	lea	0x00f80000,a1
+	movel	a0@,d7
+	cmpl	a1@,d7
+	jnes	1f
+	movel	d7,d0
+	notl	d0
+	movel	d0,a0@
+	nop
+	cmpl	a1@,d0
+	jnes	1f
+/* MapROMmed A3640 present */
+	moveq	#-1,d0
+	movel	d0,a2
+1:	movel	d7,a0@
+/* Restore MMU settings */
+	.long 	0x4e7b2003	/* movec d2,tc */
+	.long 	0x4e7b3004	/* movec d3,itt0 */
+	.long 	0x4e7b4005	/* movec d4,itt1 */
+	.long 	0x4e7b5006	/* movec d5,dtt0 */
+	.long 	0x4e7b6007	/* movec d6,dtt1 */
+/* Restore cache settings */
+	.long 	0x4e7b1002	/* movec d1,cacr */
+	movel	a2,d0
+	moveml	sp@+,#0x04fc
+	rte
+");
+
+extern unsigned long maprommed();
+
+
+extern char copyall, copyallend;
+
+int main(int argc, char *argv[])
+{
+	int ch, debugflag = 0, kfd, rfd = -1, i;
+	long fast_total = 0;	     /* total Fast RAM in system */
+	struct MemHeader *mnp;
+	struct ConfigDev *cdp = NULL;
+	char *kernel_name = "vmlinux";
+	char *ramdisk_name = NULL;
+	char *memfile = NULL;
+	u_long memreq;
+	void (*startfunc)(void);
+	long startcodesize;
+	u_long *stack, text_offset;
+	unsigned char *rb3_reg = NULL, *piccolo_reg = NULL, *sd64_reg = NULL;
+
+	/* print the greet message */
+	puts("Linux/68k Amiga Bootstrap version 1.11");
+	puts("Copyright 1993,1994 by Hamish Macdonald and Greg Harp\n");
+
+	/* machine is Amiga */
+	bi.machtype = MACH_AMIGA;
+
+	/* check arguments */
+	while ((ch = getopt(argc, argv, "dk:r:m:")) != EOF)
+		switch (ch) {
+		    case 'd':
+			debugflag = 1;
+			break;
+		    case 'k':
+			kernel_name = optarg;
+			break;
+		    case 'r':
+			ramdisk_name = optarg;
+			break;
+		    case 'm':
+			memfile = optarg;
+			break;
+		    case '?':
+		    default:
+			usage();
+		}
+	argc -= optind;
+	argv += optind;
+
+	SysBase = *(struct ExecBase **)4;
+
+	/* Memory & AutoConfig based on 'unix_boot.c' by C= */
+
+	/* open Expansion Library */
+	ExpansionBase = (struct ExpansionBase *)OpenLibrary("expansion.library", 36);
+	if (!ExpansionBase) {
+		puts("Unable to open expansion.library V36 or greater!  Aborting...");
+		exit(EXIT_FAILURE);
+	}
+
+	/* find all of the autoconfig boards in the system */
+	cdp = (struct ConfigDev *)FindConfigDev(cdp, -1, -1);
+	for (i=0; (i < NUM_AUTO) && cdp; i++) {
+		/* copy the contents of each structure into our boot info */
+		memcpy(&bi.bi_amiga.autocon[i], cdp, sizeof(struct ConfigDev));
+
+		/* count this device */
+		bi.bi_amiga.num_autocon++;
+
+		/* get next device */
+		cdp = (struct ConfigDev *)FindConfigDev(cdp, -1, -1);
+	}
+
+	/* find out the memory in the system */
+	for (mnp = (struct MemHeader *)SysBase->MemList.l_head;
+	     (bi.num_memory < NUM_MEMINFO) && mnp->mh_Node.ln_Succ;
+	     mnp = (struct MemHeader *)mnp->mh_Node.ln_Succ)
+	{
+		struct MemHeader mh;
+
+		/* copy the information */
+		mh = *mnp;
+
+		/* if we suspect that Kickstart is shadowed in an A3000,
+		   modify the entry to show 512K more at the top of RAM
+		   Check first for a MapROMmed A3640 board: overwriting the
+		   Kickstart image causes an infinite lock-up on reboot! */
+
+		if (mh.mh_Upper == (void *)0x07f80000)
+			if ((SysBase->AttnFlags & AFF_68040) && Supervisor(maprommed))
+				printf("A3640 MapROM detected.\n");
+			else {
+				mh.mh_Upper = (void *)0x08000000;
+				printf("A3000 shadowed Kickstart detected.\n");
+			}
+
+		/* if we suspect that Kickstart is zkicked,
+		   modify the entry to show 512K more at the botton of RAM */
+		if (mh.mh_Lower == (void *)0x00280020) {
+		    mh.mh_Lower =  (void *)0x00200000;
+		    printf("ZKick detected.\n");
+		}
+
+		/*
+		 * If this machine has "LOCAL" memory between 0x07000000
+		 * and 0x080000000, then we'll call it an A3000.
+		 */
+		if (mh.mh_Lower >= (void *)0x07000000 &&
+		    mh.mh_Lower <  (void *)0x08000000 &&
+		    (mh.mh_Attributes & MEMF_LOCAL))
+			bi.bi_amiga.model = AMI_3000;
+
+		/* mask the memory limit values */
+		mh.mh_Upper = (void *)((u_long)mh.mh_Upper & 0xfffff000);
+		mh.mh_Lower = (void *)((u_long)mh.mh_Lower & 0xfffff000);
+
+		/* if fast memory */
+		if (mh.mh_Attributes & MEMF_FAST) {
+			unsigned long size;
+
+			/* record the start */
+			bi.memory[bi.num_memory].addr = (u_long)mh.mh_Lower;
+
+			/* set the size value to the size of this block */
+			size = (u_long)mh.mh_Upper - (u_long)mh.mh_Lower;
+
+			/* mask off to a 256K increment */
+			size &= 0xfffc0000;
+
+			fast_total += size;
+
+			if (size > 0)
+				/* count this block */
+				bi.memory[bi.num_memory++].size  = size;
+
+		} else if (mh.mh_Attributes & MEMF_CHIP) {
+			/* if CHIP memory, record the size */
+			bi.bi_amiga.chip_size =
+				(u_long)mh.mh_Upper; /* - (u_long)mh.mh_Lower; */
+		}
+	}
+
+	CloseLibrary((struct Library *)ExpansionBase);
+
+	/*
+	 * if we have a memory file, read the memory information from it
+	 */
+	if (memfile) {
+	    FILE *fp;
+	    int i;
+
+	    if ((fp = fopen (memfile, "r")) == NULL) {
+		perror ("open memory file");
+		fprintf (stderr, "Cannot open memory file %s\n", memfile);
+		exit (EXIT_FAILURE);
+	    }
+
+	    if (fscanf (fp, "%lu", &bi.bi_amiga.chip_size) != 1) {
+		fprintf (stderr, "memory file does not contain chip memory size\n");
+		fclose (fp);
+		exit (EXIT_FAILURE);
+	    }
+		
+	    for (i = 0; i < NUM_MEMINFO; i++) {
+		if (fscanf (fp, "%lx %lu", &bi.memory[i].addr,
+			    &bi.memory[i].size) != 2)
+		    break;
+	    }
+
+	    fclose (fp);
+
+	    if (i != bi.num_memory && i > 0)
+		bi.num_memory = i;
+	}
+
+	/* get info from ExecBase */
+	bi.bi_amiga.vblank = SysBase->VBlankFrequency;
+	bi.bi_amiga.psfreq = SysBase->PowerSupplyFrequency;
+	bi.bi_amiga.eclock = SysBase->EClockFrequency;
+
+	/* open graphics library */
+	GfxBase = (struct GfxBase *)OpenLibrary ("graphics.library", 0);
+
+	/* determine chipset */
+	bi.bi_amiga.chipset = CS_STONEAGE;
+	if(GfxBase)
+	{
+	    if(GfxBase->ChipRevBits0 & GFXG_AGA)
+	    {
+		bi.bi_amiga.chipset = CS_AGA;
+		/*
+		 *  we considered this machine to be an A3000 because of its
+		 *  local memory just beneath $8000000; now if it has AGA, it
+		 *  must be an A4000
+		 *  except the case no RAM is installed on the motherboard but
+		 *  on an additional card like FastLane Z3 or on the processor
+		 *  board itself. Gotta check this out.
+		 */
+		bi.bi_amiga.model =
+		    (bi.bi_amiga.model == AMI_3000) ? AMI_4000 : AMI_1200;
+	    }
+	    else if(GfxBase->ChipRevBits0 & GFXG_ECS)
+		bi.bi_amiga.chipset = CS_ECS;
+	    else if(GfxBase->ChipRevBits0 & GFXG_OCS)
+		bi.bi_amiga.chipset = CS_OCS;
+	}
+
+	/* Display amiga model */
+	switch (bi.bi_amiga.model) {
+	    case AMI_UNKNOWN:
+		break;
+	    case AMI_500:
+		printf ("Amiga 500 ");
+		break;
+	    case AMI_2000:
+		printf ("Amiga 2000 ");
+		break;
+	    case AMI_3000:
+		printf ("Amiga 3000 ");
+		break;
+	    case AMI_4000:
+		printf ("Amiga 4000 ");
+		break;
+	    case AMI_1200:		/* this implies an upgraded model   */
+		printf ("Amiga 1200 "); /* equipped with at least 68030 !!! */
+		break;
+	}
+
+	/* display and set the CPU <type */
+	printf("CPU: ");
+	if (SysBase->AttnFlags & AFF_68040) {
+		printf("68040");
+		bi.cputype = CPU_68040;
+		if (SysBase->AttnFlags & AFF_FPU40) {
+			printf(" with internal FPU");
+			bi.cputype |= FPU_68040;
+		} else
+			printf(" without FPU");
+	} else {
+		if (SysBase->AttnFlags & AFF_68030) {
+			printf("68030");
+			bi.cputype = CPU_68030;
+		} else if (SysBase->AttnFlags & AFF_68020) {
+			printf("68020 (Do you have an MMU?)");
+			bi.cputype = CPU_68020;
+		} else {
+			puts("Insufficient for Linux.  Aborting...");
+			printf("SysBase->AttnFlags = %#x\n", SysBase->AttnFlags);
+			exit (EXIT_FAILURE);
+		}
+		if (SysBase->AttnFlags & AFF_68882) {
+			printf(" with 68882 FPU");
+			bi.cputype |= FPU_68882;
+		} else if (SysBase->AttnFlags & AFF_68881) {
+			printf(" with 68881 FPU");
+			bi.cputype |= FPU_68881;
+		} else
+			printf(" without FPU");
+	}
+
+	switch(bi.bi_amiga.chipset)
+	{
+	    case CS_STONEAGE:
+		printf(", old or unknown chipset");
+		break;
+	    case CS_OCS:
+		printf(", OCS");
+		break;
+	    case CS_ECS:
+		printf(", ECS");
+		break;
+	    case CS_AGA:
+		printf(", AGA chipset");
+		break;
+	}
+
+	putchar ('\n');
+	putchar ('\n');
+
+	/*
+	 * Copy command line options into the kernel command line.
+	 */
+	i = 0;
+	while (argc--) {
+		if ((i+strlen(*argv)+1) < CL_SIZE) {
+			i += strlen(*argv) + 1;
+			if (bi.command_line[0])
+				strcat (bi.command_line, " ");
+			strcat (bi.command_line, *argv++);
+		}
+	}
+	printf ("Command line is '%s'\n", bi.command_line);
+
+	/* display the clock statistics */
+	printf("Vertical Blank Frequency: %dHz\nPower Supply Frequency: %dHz\n",
+	       bi.bi_amiga.vblank, bi.bi_amiga.psfreq);
+	printf("EClock Frequency: %7.5fKHz\n\n",
+	       (float)bi.bi_amiga.eclock / 1000);
+
+	/* display autoconfig devices */
+	if (bi.bi_amiga.num_autocon) {
+		printf("Found %d AutoConfig Device%s", bi.bi_amiga.num_autocon,
+		       (bi.bi_amiga.num_autocon > 1)?"s\n":"\n");
+		for (i=0; i<bi.bi_amiga.num_autocon; i++)
+		{
+			printf("Device %d: addr = %08lx\n", i,
+			       (u_long)bi.bi_amiga.autocon[i].cd_BoardAddr);
+			/* check for a Rainbow 3 and prepare to reset it if there is one */
+			if ( (bi.bi_amiga.autocon[i].cd_Rom.er_Manufacturer == MANUF_HELFRICH1) &&
+				 (bi.bi_amiga.autocon[i].cd_Rom.er_Product == PROD_RAINBOW3) )
+			{
+				printf("(Found a Rainbow 3 board - will reset it at kernel boot time)\n");
+				rb3_reg = (unsigned char *)(bi.bi_amiga.autocon[i].cd_BoardAddr + 0x01002000);
+			}
+
+			/* check for a Piccolo and prepare to reset it if there is one */
+			if ( (bi.bi_amiga.autocon[i].cd_Rom.er_Manufacturer == MANUF_HELFRICH2) &&
+				 (bi.bi_amiga.autocon[i].cd_Rom.er_Product == PROD_PICCOLO_REG) )
+			{
+				printf("(Found a Piccolo board - will reset it at kernel boot time)\n");
+				piccolo_reg = (unsigned char *)(bi.bi_amiga.autocon[i].cd_BoardAddr + 0x8000);
+			}
+
+			/* check for a SD64 and prepare to reset it if there is one */
+			if ( (bi.bi_amiga.autocon[i].cd_Rom.er_Manufacturer == MANUF_HELFRICH2) &&
+				 (bi.bi_amiga.autocon[i].cd_Rom.er_Product == PROD_SD64_REG) )
+			{
+				printf("(Found a SD64 board - will reset it at kernel boot time)\n");
+				sd64_reg = (unsigned char *)(bi.bi_amiga.autocon[i].cd_BoardAddr + 0x8000);
+			}
+
+			/* what this code lacks - what if there are several boards of  */
+			/* the same brand ? In that case I should reset them one after */
+			/* the other, which is currently not done - a rare case...FN   */
+			/* ok, MY amiga currently hosts all three of the above boards ;-) */
+		}
+	} else
+		puts("No AutoConfig Devices Found");
+
+	/* display memory */
+	if (bi.num_memory) {
+		printf("\n%d Block%sof Memory Found\n", bi.num_memory,
+		       (bi.num_memory > 1)?"s ":" ");
+		for (i=0; i<bi.num_memory; i++) {
+			printf("Block %d: %08lx to %08lx (%ldKB)\n",
+			       i, bi.memory[i].addr,
+			       bi.memory[i].addr + bi.memory[i].size,
+			       bi.memory[i].size >> 10);
+		}
+	} else {
+		puts("No memory found?!  Aborting...");
+		exit(10);
+	}
+
+	/* display chip memory size */
+	printf ("%ldK of CHIP memory\n", bi.bi_amiga.chip_size >> 10);
+
+	start_mem = bi.memory[0].addr;
+	mem_size = bi.memory[0].size;
+
+	/* tell us where the kernel will go */
+	printf("\nThe kernel will be located at %08lx\n", start_mem);
+
+	/* verify that there is enough Chip RAM */
+	if (bi.bi_amiga.chip_size < 512*1024) {
+		puts("\nNot enough Chip RAM in this system.  Aborting...");
+		exit(10);
+	}
+
+	/* verify that there is enough Fast RAM */
+	if (fast_total < 2*1024*1024) {
+		puts("\nNot enough Fast RAM in this system.  Aborting...");
+		exit(10);
+	}
+
+	/* open kernel executable and read exec header */
+	if ((kfd = open (kernel_name, O_RDONLY)) == -1) {
+		fprintf (stderr, "Unable to open kernel file %s\n", kernel_name);
+		exit (EXIT_FAILURE);
+	}
+
+	if (read (kfd, (void *)&kexec, sizeof(kexec)) != sizeof(kexec)) {
+		fprintf (stderr, "Unable to read exec header from %s\n",
+			 kernel_name);
+		exit (EXIT_FAILURE);
+	}
+
+	switch (N_MAGIC(kexec)) {
+	  case ZMAGIC:
+	    text_offset = N_TXTOFF(kexec);
+	    break;
+	  case QMAGIC:
+	    text_offset = sizeof(kexec);
+	    /* the text size includes the exec header; remove this */
+	    kexec.a_text -= sizeof(kexec);
+	    break;
+	  default:
+	    fprintf (stderr, "Wrong magic number %lo in kernel header\n",
+		     N_MAGIC(kexec));
+	    exit (EXIT_FAILURE);
+	}
+
+	/* Load the kernel at one page after start of mem */
+	start_mem += PAGE_SIZE;
+	mem_size -= PAGE_SIZE;
+	/* Align bss size to multiple of four */
+	kexec.a_bss = (kexec.a_bss + 3) & ~3;
+
+	if (ramdisk_name) {
+		if ((rfd = open (ramdisk_name, O_RDONLY)) == -1) {
+			fprintf (stderr, "Unable to open ramdisk file %s\n",
+				 ramdisk_name);
+			exit (EXIT_FAILURE);
+		}
+		/* record ramdisk size */
+		bi.ramdisk_size = (lseek (rfd, 0, L_XTND) + 1023) >> 10;
+	} else
+		bi.ramdisk_size = 0;
+
+	rd_size = bi.ramdisk_size << 10;
+	bi.ramdisk_addr = (u_long)start_mem + mem_size - rd_size;
+
+	memreq = kexec.a_text + kexec.a_data + sizeof(bi) + rd_size;
+	if (!(memptr = (char *)AllocMem (memreq, MEMF_FAST | MEMF_CLEAR))) {
+		fprintf (stderr, "Unable to allocate memory\n");
+		exit (EXIT_FAILURE);
+	}
+
+	if (lseek (kfd, text_offset, L_SET) == -1) {
+		fprintf (stderr, "Failed to seek to text\n");
+		FreeMem ((void *)memptr, memreq);
+		exit (EXIT_FAILURE);
+	}
+	if (read (kfd, memptr, kexec.a_text) != kexec.a_text) {
+		fprintf (stderr, "Failed to read text\n");
+		FreeMem ((void *)memptr, memreq);
+		exit (EXIT_FAILURE);
+	}
+
+	/* data follows immediately after text */
+	if (read (kfd, memptr + kexec.a_text, kexec.a_data) != kexec.a_data) {
+		fprintf (stderr, "Failed to read data\n");
+		FreeMem ((void *)memptr, memreq);
+		exit (EXIT_FAILURE);
+	}
+	close (kfd);
+
+	/* copy the boot_info struct to the end of the kernel image */
+	memcpy ((void *)(memptr + kexec.a_text + kexec.a_data), &bi,
+		sizeof(bi));
+
+	if (rfd != -1) {
+		if (lseek (rfd, 0, L_SET) == -1) {
+			fprintf (stderr, "Failed to seek to beginning of ramdisk file\n");
+			FreeMem ((void *)memptr, memreq);
+			exit (EXIT_FAILURE);
+		}
+		if (read (rfd, memptr + kexec.a_text + kexec.a_data 
+			  + sizeof(bi), rd_size) != rd_size) {
+			fprintf (stderr, "Failed to read ramdisk file\n");
+			FreeMem ((void *)memptr, memreq);
+			exit (EXIT_FAILURE);
+		}
+		close (rfd);
+	}
+
+	/* allocate temporary chip ram stack */
+	stack = (u_long *)AllocMem( TEMP_STACKSIZE, MEMF_CHIP|MEMF_CLEAR);
+	if (!stack) {
+		fprintf (stderr, "Unable to allocate memory for stack\n");
+		FreeMem ((void *)memptr, memreq);
+		exit (EXIT_FAILURE);
+	}
+
+	/* allocate chip ram for copy of startup code */
+	startcodesize = &copyallend - &copyall;
+	startfunc = (void (*)(void))AllocMem( startcodesize, MEMF_CHIP);
+	if (!startfunc) {
+		fprintf (stderr, "Unable to allocate memory for code\n");
+		FreeMem ((void *)memptr, memreq);
+		FreeMem ((void *)stack, TEMP_STACKSIZE);
+		exit (EXIT_FAILURE);
+	}
+
+	/* copy startup code to CHIP RAM */
+	memcpy (startfunc, &copyall, startcodesize);
+
+	if (debugflag) {
+		if (bi.ramdisk_size)
+			printf ("RAM disk at %#lx, size is %ldK\n",
+				(u_long)memptr + kexec.a_text + kexec.a_data,
+				bi.ramdisk_size);
+
+		printf ("\nKernel text at %#lx, code size %x\n",
+			start_mem, kexec.a_text);
+		printf ("Kernel data at %#lx, data size %x\n",
+			start_mem + kexec.a_text, kexec.a_data );
+		printf ("Kernel bss  at %#lx, bss  size %x\n",
+			start_mem + kexec.a_text + kexec.a_data,
+			kexec.a_bss );
+		printf ("boot info at %#lx\n", start_mem + kexec.a_text
+			+ kexec.a_data + kexec.a_bss);
+
+		printf ("\nKernel entry is %#x\n", kexec.a_entry );
+
+		printf ("ramdisk dest top is %#lx\n", start_mem + mem_size);
+		printf ("ramdisk lower limit is %#lx\n",
+			(u_long)(memptr + kexec.a_text + kexec.a_data));
+		printf ("ramdisk src top is %#lx\n",
+			(u_long)(memptr + kexec.a_text + kexec.a_data)
+			+ rd_size);
+
+		printf ("Type a key to continue the Linux boot...");
+		fflush (stdout);
+		getchar();
+	}
+
+	/* wait for things to settle down */
+	sleep(2);
+
+	/* FN: If a Rainbow III board is present, reset it to disable */
+	/* its (possibly activated) vertical blank interrupts as the */
+	/* kernel is not yet prepared to handle them (level 6). */
+	if (rb3_reg != NULL)
+	{
+		/* set RESET bit in special function register */
+		*rb3_reg = 0x01;
+		/* actually, only a few cycles delay are required... */
+		sleep(1);
+		/* clear reset bit */
+		*rb3_reg = 0x00;
+	}
+
+	/* the same stuff as above, for the Piccolo board. */
+	/* this also has the side effect of resetting the board's */
+	/* output selection logic to use the Amiga's display in single */
+	/* monitor systems - which is currently what we want. */
+	if (piccolo_reg != NULL)
+	{
+		/* set RESET bit in special function register */
+		*piccolo_reg = 0x01;
+		/* actually, only a few cycles delay are required... */
+		sleep(1);
+		/* clear reset bit */
+		*piccolo_reg = 0x51;
+	}
+
+	/* the same stuff as above, for the SD64 board. */
+	/* just as on the Piccolo, this also resets the monitor switch */
+	if (sd64_reg != NULL)
+	{
+		/* set RESET bit in special function register */
+		*sd64_reg = 0x1f;
+		/* actually, only a few cycles delay are required... */
+		sleep(1);
+	/* clear reset bit AND switch monitor bit (0x20) */
+	*sd64_reg = 0x4f;
+	}
+
+	if (GfxBase) {
+		/* set graphics mode to a nice normal one */
+		LoadView (NULL);
+		CloseLibrary ((struct Library *)GfxBase);
+	}
+
+	Disable();
+
+	/* Turn off all DMA */
+	custom.dmacon = DMAF_ALL | DMAF_MASTER;
+
+	/* turn off caches */
+	CacheControl (0L, ~0L);
+
+	/* Go into supervisor state */
+	SuperState ();
+
+	/* setup stack */
+	change_stack ((char *) stack + TEMP_STACKSIZE);
+
+	/* turn off any mmu translation */
+	disable_mmu ();
+
+	/* execute the copy-and-go code (from CHIP RAM) */
+	startfunc();
+
+	/* NOTREACHED */
+}

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov with Sam's (original) version
of this