patch-2.4.5 linux/arch/ppc/boot/mbx/misc.c

• Lines: 297
• Date: Thu May 24 15:02:06 2001
• Orig file: v2.4.4/linux/arch/ppc/boot/mbx/misc.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.4/linux/arch/ppc/boot/mbx/misc.c linux/arch/ppc/boot/mbx/misc.c
@@ -0,0 +1,296 @@
+/*
+ * BK Id: SCCS/s.misc.c 1.9 05/18/01 07:54:04 patch
+ */
+/*
+ * Adapted for PowerPC by Gary Thomas
+ *
+ * Rewritten by Cort Dougan (cort@cs.nmt.edu)
+ * One day to be replaced by a single bootloader for chrp/prep/pmac. -- Cort
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include "zlib.h"
+#include <asm/residual.h>
+#include <linux/elf.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <asm/mmu.h>
+#ifdef CONFIG_8xx
+#include <asm/mpc8xx.h>
+#endif
+#ifdef CONFIG_8260
+#include <asm/mpc8260.h>
+#endif
+
+/*
+ * The following references are needed to cause the linker to pull in the
+ * gzimage.o and rdimage.o files.  These object files are special,
+ * since they get placed into the .gzimage and .rdimage ELF sections 
+ * of the zvmlinux and zvmlinux.initrd files.
+ */
+extern char dummy_for_gzimage;
+extern char dummy_for_rdimage;
+
+/*
+ * Please send me load/board info and such data for hardware not
+ * listed here so I can keep track since things are getting tricky
+ * with the different load addrs with different firmware.  This will
+ * help to avoid breaking the load/boot process.
+ * -- Cort
+ */
+char *avail_ram;
+char *end_avail;
+
+/* See comment below.....
+*/
+unsigned int initrd_offset, initrd_size;
+
+/* Because of the limited amount of memory on embedded, it presents
+ * loading problems.  The biggest is that we load this boot program
+ * into a relatively low memory address, and the Linux kernel Bss often
+ * extends into this space when it get loaded.  When the kernel starts
+ * and zeros the BSS space, it also writes over the information we
+ * save here and pass to the kernel (command line and board info).
+ * On these boards, we grab some known memory holes to hold this information.
+ */
+char	cmd_buf[256];
+char	*cmd_line = cmd_buf;
+
+/* This is the default cmdline that will be given to the user at boot time..
+ * If none was specified at compile time, we'll give it one that should work.
+ * -- Tom */
+#ifdef CONFIG_CMDLINE_BOOL
+char	compiled_string[] = CONFIG_CMDLINE;
+#endif
+char	ramroot_string[] = "root=/dev/ram";
+char	netroot_string[] = "root=/dev/nfs rw";
+
+bd_t hold_resid_buf;
+bd_t *hold_residual = &hold_resid_buf;
+unsigned long initrd_start = 0, initrd_end = 0;
+char *zimage_start;
+int zimage_size;
+
+extern void puts(const char *);
+extern void putc(const char c);
+extern void udelay(long x);
+extern void puthex(unsigned long val);
+extern void * memcpy(void * __dest, __const void * __src, __kernel_size_t __n);
+extern void gunzip(void *, int, unsigned char *, int *);
+extern int tstc(void);
+extern int getc(void);
+
+unsigned long
+decompress_kernel(unsigned long load_addr, int num_words, unsigned long cksum, bd_t *bp)
+{
+	int timer;
+	extern unsigned long start;
+	char *cp, ch;
+
+#ifdef CONFIG_8260
+	/* I don't know why I didn't do it this way on the 8xx.......
+	*/
+	embed_config(&bp);
+	serial_init(bp);
+#endif
+
+	/* These values must be variables.  If not, the compiler optimizer
+	 * will remove some code, causing the size of the code to vary
+	 * when these values are zero.  This is bad because we first
+	 * compile with these zero to determine the size and offsets
+	 * in an image, than compile again with these set to the proper
+	 * discovered value.....Ya know, we used to read these from the
+	 * header a long time ago.....
+	 */
+	initrd_offset = INITRD_OFFSET;
+	initrd_size = INITRD_SIZE;
+
+	/* Grab some space for the command line and board info.  Since
+	 * we no longer use the ELF header, but it was loaded, grab
+	 * that space.
+	 */
+#ifdef CONFIG_MBX
+	cmd_line = (char *)(load_addr - 0x10000);
+
+	/* To be like everyone else, we need one too, although this
+	 * board information is passed from the boot rom.
+	 */
+	bp->bi_baudrate = 9600;
+#else
+	cmd_line = (char *)(0x200000);
+#endif
+	hold_residual = (bd_t *)(cmd_line + sizeof(cmd_buf));
+	/* copy board data */
+	if (bp)
+		memcpy(hold_residual,bp,sizeof(bd_t));
+
+	/* Set end of memory available to us.  It is always the highest
+	 * memory address provided by the board information.
+	 */
+	end_avail = (char *)(bp->bi_memsize);
+
+	puts("loaded at:     "); puthex(load_addr);
+	puts(" "); puthex((unsigned long)(load_addr + (4*num_words))); puts("\n");
+	if ( (unsigned long)load_addr != (unsigned long)&start )
+	{
+		puts("relocated to:  "); puthex((unsigned long)&start);
+		puts(" ");
+		puthex((unsigned long)((unsigned long)&start + (4*num_words)));
+		puts("\n");
+	}
+
+	if ( bp )
+	{
+		puts("board data at: "); puthex((unsigned long)bp);
+		puts(" ");
+		puthex((unsigned long)((unsigned long)bp + sizeof(bd_t)));
+		puts("\n");
+		puts("relocated to:  ");
+		puthex((unsigned long)hold_residual);
+		puts(" ");
+		puthex((unsigned long)((unsigned long)hold_residual + sizeof(bd_t)));
+		puts("\n");
+	}
+
+	/* we have to subtract 0x10000 here to correct for objdump including the
+	   size of the elf header which we strip -- Cort */
+	zimage_start = (char *)(load_addr - 0x10000 + ZIMAGE_OFFSET);
+	zimage_size = ZIMAGE_SIZE;
+
+	if ( initrd_offset )
+		initrd_start = load_addr - 0x10000 + initrd_offset;
+	else
+		initrd_start = 0;
+	initrd_end = initrd_size + initrd_start;
+
+	/*
+	 * setup avail_ram - this is the first part of ram usable
+	 * by the uncompress code. -- Cort
+	 */
+	avail_ram = (char *)PAGE_ALIGN((unsigned long)zimage_start+zimage_size);
+	if ( ((load_addr+(num_words*4)) > (unsigned long) avail_ram)
+		&& (load_addr <= 0x01000000) )
+		avail_ram = (char *)(load_addr+(num_words*4));
+	if ( (((unsigned long)&start+(num_words*4)) > (unsigned long) avail_ram)
+		&& (load_addr <= 0x01000000) )
+		avail_ram = (char *)((unsigned long)&start+(num_words*4));
+	
+	/* relocate zimage */
+	puts("zimage at:     "); puthex((unsigned long)zimage_start);
+	puts(" "); puthex((unsigned long)(zimage_size+zimage_start)); puts("\n");
+	/*
+	 * There is no reason (yet) to relocate zImage for embedded boards.
+	 * To support boot from flash rom on 8xx embedded boards, I
+	 * assume if zimage start is over 16M we are booting from flash.
+	 * In this case, avilable ram will start just above the space we
+	 * have allocated for the command buffer and board information.
+	 */
+	if ((unsigned long)zimage_start > 0x01000000)
+		avail_ram = (char *)PAGE_ALIGN((unsigned long)hold_residual + sizeof(bd_t));
+
+	/* relocate initrd */
+	if ( initrd_start )
+	{
+		puts("initrd at:     "); puthex(initrd_start);
+		puts(" "); puthex(initrd_end); puts("\n");
+
+		/* We only have to relocate initrd if we find it is in Flash
+		 * rom.  This is because the kernel thinks it can toss the
+		 * pages into the free memory pool after it is done.  Use
+		 * the same 16M test.
+		 */
+		if ((unsigned long)initrd_start > 0x01000000) {
+			memcpy ((void *)PAGE_ALIGN(-PAGE_SIZE+(unsigned long)end_avail-INITRD_SIZE),
+				(void *)initrd_start,
+				initrd_size );
+			initrd_start = PAGE_ALIGN(-PAGE_SIZE+(unsigned long)end_avail-INITRD_SIZE);
+			initrd_end = initrd_start + initrd_size;
+			end_avail = (char *)initrd_start;
+			puts("relocated to:  "); puthex(initrd_start);
+			puts(" "); puthex(initrd_end); puts("\n");
+		}
+		else {
+			avail_ram = (char *)PAGE_ALIGN((unsigned long)initrd_end);
+		}
+	}
+
+
+	puts("avail ram:     "); puthex((unsigned long)avail_ram); puts(" ");
+	puthex((unsigned long)end_avail); puts("\n");
+	puts("\nLinux/PPC load: ");
+	timer = 0;
+	cp = cmd_line;
+	/* This is where we try and pick the right command line for booting.
+	 * If we were given one at compile time, use it.  It Is Right.
+	 * If we weren't, see if we have a ramdisk.  If so, thats root.
+	 * When in doubt, give them the netroot (root=/dev/nfs rw) -- Tom */
+#ifdef CONFIG_CMDLINE_BOOL
+	memcpy (cmd_line, compiled_string, sizeof(compiled_string));
+#else
+	if (initrd_start)
+		memcpy (cmd_line, ramroot_string, sizeof(ramroot_string));
+	else
+		memcpy (cmd_line, netroot_string, sizeof(netroot_string));
+#endif
+	while ( *cp ) putc(*cp++);
+	while (timer++ < 5*1000) {
+		if (tstc()) {
+			while ((ch = getc()) != '\n' && ch != '\r') {
+				if (ch == '\b' || ch == '\177') {
+					if (cp != cmd_line) {
+						cp--;
+						puts("\b \b");
+					}
+				} else if (ch == '\030'		/* ^x */
+					   || ch == '\025') {	/* ^u */
+					while (cp != cmd_line) {
+						cp--;
+						puts("\b \b");
+					}
+				} else {
+					*cp++ = ch;
+					putc(ch);
+				}
+			}
+			break;  /* Exit 'timer' loop */
+		}
+		udelay(1000);  /* 1 msec */
+	}
+	*cp = 0;
+	puts("\nUncompressing Linux...");
+
+	gunzip(0, 0x400000, zimage_start, &zimage_size);
+	puts("done.\n");
+	puts("Now booting the kernel\n");
+	return (unsigned long)hold_residual;
+}
+
+/*
+ * PCI/ISA I/O support
+ */
+
+volatile unsigned char *ISA_io  = (unsigned char *)0x80000000;
+volatile unsigned char *ISA_mem = (unsigned char *)0xC0000000;
+
+void
+outb(int port, char val)
+{
+	/* Ensure I/O operations complete */
+	__asm__ volatile("eieio");
+	ISA_io[port] = val;
+}
+
+unsigned char
+inb(int port)
+{
+	/* Ensure I/O operations complete */
+	__asm__ volatile("eieio");
+	return (ISA_io[port]);
+}
+
+unsigned long
+local_to_PCI(unsigned long addr)
+{
+	return ((addr & 0x7FFFFFFF) | 0x80000000);
+}