patch-2.4.5 linux/arch/ppc/boot/tree/main.c

• Lines: 249
• Date: Thu May 24 15:02:07 2001
• Orig file: v2.4.4/linux/arch/ppc/boot/tree/main.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.4/linux/arch/ppc/boot/tree/main.c linux/arch/ppc/boot/tree/main.c
@@ -0,0 +1,248 @@
+/*
+ * BK Id: SCCS/s.main.c 1.7 05/18/01 06:20:29 patch
+ */
+/*
+ *    Copyright (c) 1997 Paul Mackerras <paulus@cs.anu.edu.au>
+ *      Initial Power Macintosh COFF version.
+ *    Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
+ *      Modifications for an ELF-based IBM evaluation board version.
+ *    Copyright 2000-2001 MontaVista Software Inc.
+ *	PPC405GP modifications
+ * 	Author: MontaVista Software, Inc.
+ *         	frank_rowand@mvista.com or source@mvista.com
+ * 	   	debbie_chu@mvista.com
+ *
+ *    Module name: main.c
+ *
+ *    Description:
+ *      This module does most of the real work for the boot loader. It
+ *      checks the variables holding the absolute start address and size
+ *      of the Linux kernel "image" and initial RAM disk "initrd" sections
+ *      and if they are present, moves them to their "proper" locations.
+ *
+ *      For the Linux kernel, "proper" is physical address 0x00000000.
+ *      For the RAM disk, "proper" is the image's size below the top
+ *      of physical memory. The Linux kernel may be in either raw
+ *      binary form or compressed with GNU zip (aka gzip).
+ *
+ *    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.
+ *
+ */
+
+#include <linux/config.h>
+#include <asm/ppc4xx.h>
+
+#include "nonstdio.h"
+#include "irSect.h"
+#if defined(CONFIG_SERIAL_CONSOLE)
+#include "ns16550.h"
+#endif /* CONFIG_SERIAL_CONSOLE */
+
+
+/* Preprocessor Defines */
+
+/*
+ * Location of the IBM boot ROM function pointer address for retrieving
+ * the board information structure.
+ */
+
+#define	BOARD_INFO_VECTOR	0xFFFE0B50
+
+/* 
+ * Warning: the board_info doesn't contain valid data until get_board_info() 
+ * 	    gets called in start().
+ */
+#define RAM_SIZE        board_info.bi_memsize 
+
+#define	RAM_PBASE	0x00000000
+#define	RAM_PEND	(RAM_PBASE + RAM_SIZE)
+
+#define	RAM_VBASE	0xC0000000
+#define	RAM_VEND	(RAM_VBASE + RAM_SIZE)
+
+#define	RAM_START	RAM_PBASE
+#define	RAM_END		RAM_PEND
+#define	RAM_FREE	(imageSect_start + imageSect_size + initrdSect_size)
+
+#define	PROG_START	RAM_START
+
+
+/* Function Macros */
+
+#define	ALIGN_UP(x, align)	(((x) + ((align) - 1)) & ~((align) - 1))
+
+#define stringify(s)    tostring(s)
+#define tostring(s)     #s
+
+#define mtdcr(rn, v)    asm volatile("mtdcr " stringify(rn) ",%0" : : "r" (v))
+#define mfdcr(rn)       ({unsigned int rval; \
+                        asm volatile("mfdcr %0," stringify(rn) \
+                                     : "=r" (rval)); rval;})
+#define DCRN_MALCR      0x180   /* MAL Configuration                          */
+#define   MALCR_SR      0x80000000      /* Software Reset                     */
+
+/* Global Variables */
+
+/* Needed by zalloc and zfree for allocating memory */
+
+char *avail_ram;	/* Indicates start of RAM available for heap */
+char *end_avail;	/* Indicates end of RAM available for heap */
+
+bd_t	board_info;
+
+/*
+ * XXX - Until either the IBM boot ROM provides a way of passing arguments to
+ *       the program it launches or until I/O is working in the boot loader,
+ *       this is a good spot to pass in command line arguments to the kernel
+ *       (e.g. console=tty0).
+ */
+
+
+/*
+** The bootrom may change bootrom_cmdline to point to a buffer in the
+** bootrom.
+*/
+char *bootrom_cmdline = "";
+char treeboot_bootrom_cmdline[512];
+
+#ifdef CONFIG_CMDLINE
+char *cmdline = CONFIG_CMDLINE;
+#else
+char *cmdline = "";
+#endif
+
+/* Function Prototypes */
+
+extern void *zalloc(void *x, unsigned items, unsigned size);
+
+/* serial I/O functions.
+ * These should have generic names, although this is similar to 16550....
+ */
+static volatile unsigned char *uart0_lsr = (unsigned char *)0xef600305;
+static volatile unsigned char *uart0_xcvr = (unsigned char *)0xef600300;
+
+void
+serial_putc(void *unused, unsigned char c)
+{
+ while ((*uart0_lsr & LSR_THRE) == 0);
+ *uart0_xcvr = c;
+}
+
+unsigned char
+serial_getc(void *unused)
+{
+ while ((*uart0_lsr & LSR_DR) == 0);
+ return (*uart0_xcvr);
+}
+
+int
+serial_tstc(void *unused)
+{
+ return ((*uart0_lsr & LSR_DR) != 0);
+}
+
+
+void start(void)
+{
+    void *options;
+    int ns, oh, i;
+    unsigned long sa, len;
+    void *dst;
+    unsigned char *im;
+    unsigned long initrd_start, initrd_size;
+    bd_t *(*get_board_info)(void) = 
+	    (bd_t *(*)(void))(*(unsigned long *)BOARD_INFO_VECTOR);
+    bd_t *bip = NULL;
+    volatile unsigned long *em0mr0 = (long *)0xEF600800;    /* ftr fixup */
+
+
+
+#if defined(CONFIG_WALNUT)
+    /* turn off ethernet */
+    /* This is to fix a problem with early walnut bootrom. */
+
+    mtdcr(DCRN_MALCR, MALCR_SR);                /* 1st reset MAL */
+
+    while (mfdcr(DCRN_MALCR) & MALCR_SR) {};    /* wait for the reset */
+
+    *em0mr0 = 0x20000000;                       /* then reset EMAC */
+#endif
+
+
+#if 0
+    /* ftr revisit - remove printf()s */
+
+    printf("\n\nbootrom_cmdline = >%s<\n\n", bootrom_cmdline);
+    if (*bootrom_cmdline != '\0') {
+	printf("bootrom_cmdline != NULL, copying it into cmdline\n\n");
+	*treeboot_bootrom_cmdline = '\0';
+	strcat(treeboot_bootrom_cmdline, bootrom_cmdline);
+	cmdline = treeboot_bootrom_cmdline;
+    }
+#endif
+
+
+    if ((bip = get_board_info()) != NULL)
+	    memcpy(&board_info, bip, sizeof(bd_t));
+
+    /* Init RAM disk (initrd) section */
+
+    if (initrdSect_start != 0 && (initrd_size = initrdSect_size) != 0) {
+        initrd_start = (RAM_END - initrd_size) & ~0xFFF;
+
+	_printk("Initial RAM disk at 0x%08x (%u bytes)\n",
+	       initrd_start, initrd_size);
+
+	memcpy((char *)initrd_start,
+	       (char *)(initrdSect_start),
+	       initrdSect_size);
+
+	end_avail = (char *)initrd_start;
+    } else {
+	initrd_start = initrd_size = 0;
+	end_avail = (char *)RAM_END;
+    }
+
+    /* Linux kernel image section */
+	
+    im = (unsigned char *)(imageSect_start);
+    len = imageSect_size;
+    dst = (void *)PROG_START;
+
+    /* Check for the gzip archive magic numbers */
+
+    if (im[0] == 0x1f && im[1] == 0x8b) {
+
+        /* The gunzip routine needs everything nice and aligned */
+
+	void *cp = (void *)ALIGN_UP(RAM_FREE, 8);
+	avail_ram = (void *)(cp + ALIGN_UP(len, 8));	/* used by zalloc() */
+	memcpy(cp, im, len);
+
+	/* I'm not sure what the 0x200000 parameter is for, but it works. */
+	/* It tells gzip the end of the area you wish to reserve, and it
+	 * can use data past that point....unfortunately, this value
+	 * isn't big enough (luck ran out).  -- Dan
+	 */
+
+	gunzip(dst, 0x400000, cp, (int *)&len);
+    } else {
+	memmove(dst, im, len);
+    }
+
+
+    flush_cache(dst, len);
+
+    sa = (unsigned long)dst;
+
+    (*(void (*)())sa)(&board_info,
+		      initrd_start,
+		      initrd_start + initrd_size,
+		      cmdline,
+		      cmdline + strlen(cmdline));
+
+    pause();
+}