1 files changed, 296 insertions, 0 deletions
diff --git a/arch/x86/lib/zimage.c b/arch/x86/lib/zimage.c
new file mode 100644
index 0000000..cc4b40e
--- /dev/null
+++ b/arch/x86/lib/zimage.c
@@ -0,0 +1,296 @@
+/*
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * Linux x86 zImage and bzImage loading
+ *
+ * based on the procdure described in
+ * linux/Documentation/i386/boot.txt
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/ptrace.h>
+#include <asm/zimage.h>
+#include <asm/realmode.h>
+#include <asm/byteorder.h>
+#include <asm/bootparam.h>
+#include <asm/ic/sc520.h>
+
+/*
+ * Memory lay-out:
+ *
+ * relative to setup_base (which is 0x90000 currently)
+ *
+ *	0x0000-0x7FFF	Real mode kernel
+ *	0x8000-0x8FFF	Stack and heap
+ *	0x9000-0x90FF	Kernel command line
+ */
+#define DEFAULT_SETUP_BASE  0x90000
+#define COMMAND_LINE_OFFSET 0x9000
+#define HEAP_END_OFFSET     0x8e00
+
+#define COMMAND_LINE_SIZE   2048
+
+static void build_command_line(char *command_line, int auto_boot)
+{
+	char *env_command_line;
+
+	command_line[0] = '\0';
+
+	env_command_line =  getenv("bootargs");
+
+	/* set console= argument if we use a serial console */
+	if (NULL == strstr(env_command_line, "console=")) {
+		if (0==strcmp(getenv("stdout"), "serial")) {
+
+			/* We seem to use serial console */
+			sprintf(command_line, "console=ttyS0,%s ",
+				 getenv("baudrate"));
+		}
+	}
+
+	if (auto_boot) {
+		strcat(command_line, "auto ");
+	}
+
+	if (NULL != env_command_line) {
+		strcat(command_line, env_command_line);
+	}
+
+
+	printf("Kernel command line: \"%s\"\n", command_line);
+}
+
+void *load_zimage(char *image, unsigned long kernel_size,
+		  unsigned long initrd_addr, unsigned long initrd_size,
+		  int auto_boot)
+{
+	void *setup_base;
+	int setup_size;
+	int bootproto;
+	int big_image;
+	void *load_address;
+
+	struct setup_header *hdr = (struct setup_header *)(image + SETUP_SECTS_OFF);
+
+	setup_base = (void*)DEFAULT_SETUP_BASE;	/* base address for real-mode segment */
+
+	if (KERNEL_MAGIC != hdr->boot_flag) {
+		printf("Error: Invalid Boot Flag (found 0x%04x, expected 0x%04x)\n",
+				hdr->boot_flag, KERNEL_MAGIC);
+		return 0;
+	} else {
+		printf("Valid Boot Flag\n");
+	}
+
+	/* determine boot protocol version */
+	if (KERNEL_V2_MAGIC == hdr->header) {
+		printf("Magic signature found\n");
+
+		bootproto = hdr->version;
+	} else {
+		/* Very old kernel */
+		printf("Magic signature not found\n");
+		bootproto = 0x0100;
+	}
+
+	/* determine size of setup */
+	if (0 == hdr->setup_sects) {
+		printf("Setup Sectors = 0 (defaulting to 4)\n");
+		setup_size = 5 * 512;
+	} else {
+		setup_size = (hdr->setup_sects + 1) * 512;
+	}
+
+	printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
+
+	if (setup_size > SETUP_MAX_SIZE) {
+		printf("Error: Setup is too large (%d bytes)\n", setup_size);
+	}
+
+	/* Determine image type */
+	big_image = (bootproto >= 0x0200) && (hdr->loadflags & BIG_KERNEL_FLAG);
+
+	/* Determine load address */
+	load_address = (void*)(big_image ? BZIMAGE_LOAD_ADDR : ZIMAGE_LOAD_ADDR);
+
+	/* load setup */
+	printf("Moving Real-Mode Code to 0x%8.8lx (%d bytes)\n", (ulong)setup_base, setup_size);
+	memmove(setup_base, image, setup_size);
+
+	printf("Using boot protocol version %x.%02x\n",
+	       (bootproto & 0xff00) >> 8, bootproto & 0xff);
+
+	if (bootproto == 0x0100) {
+
+		*(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
+		*(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
+
+		/* A very old kernel MUST have its real-mode code
+		 * loaded at 0x90000 */
+
+		if ((u32)setup_base != 0x90000) {
+			/* Copy the real-mode kernel */
+			memmove((void*)0x90000, setup_base, setup_size);
+			/* Copy the command line */
+			memmove((void*)0x99000, setup_base+COMMAND_LINE_OFFSET,
+			       COMMAND_LINE_SIZE);
+
+			setup_base = (void*)0x90000;		 /* Relocated */
+		}
+
+		/* It is recommended to clear memory up to the 32K mark */
+		memset((void*)0x90000 + setup_size, 0, SETUP_MAX_SIZE-setup_size);
+	}
+
+	/* We are now setting up the real-mode version of the header */
+	hdr = (struct setup_header *)(setup_base + SETUP_SECTS_OFF);
+
+	if (bootproto >= 0x0200) {
+		hdr->type_of_loader = 8;
+
+		if (hdr->setup_sects >= 15)
+			printf("Linux kernel version %s\n", (char *)
+					(setup_base + (hdr->kernel_version + 0x200)));
+		else
+			printf("Setup Sectors < 15 - Cannot print kernel version.\n");
+
+		if (initrd_addr) {
+			printf("Initial RAM disk at linear address 0x%08lx, size %ld bytes\n",
+			       initrd_addr, initrd_size);
+
+			hdr->ramdisk_image = initrd_addr;
+			hdr->ramdisk_size = initrd_size;
+		}
+	}
+
+	if (bootproto >= 0x0201) {
+		hdr->heap_end_ptr = HEAP_END_OFFSET;
+		hdr->loadflags |= HEAP_FLAG;
+	}
+
+	if (bootproto >= 0x0202) {
+		hdr->cmd_line_ptr = (u32)setup_base + COMMAND_LINE_OFFSET;
+	} else if (bootproto >= 0x0200) {
+
+		*(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
+		*(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
+
+		hdr->setup_move_size = 0x9100;
+	}
+
+	if (bootproto >= 0x0204)
+		kernel_size = hdr->syssize * 16;
+	else
+		kernel_size -= setup_size;
+
+
+	if (big_image) {
+		if ((kernel_size) > BZIMAGE_MAX_SIZE) {
+			printf("Error: bzImage kernel too big! (size: %ld, max: %d)\n",
+			       kernel_size, BZIMAGE_MAX_SIZE);
+			return 0;
+		}
+
+	} else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
+		printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
+		       kernel_size, ZIMAGE_MAX_SIZE);
+		return 0;
+	}
+
+	/* build command line at COMMAND_LINE_OFFSET */
+	build_command_line(setup_base + COMMAND_LINE_OFFSET, auto_boot);
+
+	printf("Loading %czImage at address 0x%08x (%ld bytes)\n", big_image ? 'b' : ' ',
+	       (u32)load_address, kernel_size);
+
+
+	memmove(load_address, image + setup_size, kernel_size);
+
+	/* ready for booting */
+	return setup_base;
+}
+
+void boot_zimage(void *setup_base)
+{
+	struct pt_regs regs;
+
+	memset(&regs, 0, sizeof(struct pt_regs));
+	regs.xds = (u32)setup_base >> 4;
+	regs.xes = regs.xds;
+	regs.xss = regs.xds;
+	regs.esp = 0x9000;
+	regs.eflags = 0;
+	enter_realmode(((u32)setup_base+SETUP_START_OFFSET)>>4, 0, &regs, &regs);
+}
+
+int do_zboot (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	void *base_ptr;
+	void *bzImage_addr = NULL;
+	char *s;
+	ulong bzImage_size = 0;
+
+	disable_interrupts();
+
+	/* Setup board for maximum PC/AT Compatibility */
+	setup_pcat_compatibility();
+
+	if (argc >= 2)
+		/* argv[1] holds the address of the bzImage */
+		s = argv[1];
+	else
+		s = getenv("fileaddr");
+
+	if (s)
+		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
+
+	if (argc >= 3)
+		/* argv[2] holds the size of the bzImage */
+		bzImage_size = simple_strtoul(argv[2], NULL, 16);
+
+	/* Lets look for*/
+	base_ptr = load_zimage (bzImage_addr, bzImage_size, 0, 0, 0);
+
+	if (NULL == base_ptr) {
+		printf ("## Kernel loading failed ...\n");
+	} else {
+		printf ("## Transferring control to Linux (at address %08x) ...\n",
+			(u32)base_ptr);
+
+		/* we assume that the kernel is in place */
+		printf("\nStarting kernel ...\n\n");
+
+		boot_zimage(base_ptr);
+		/* does not return */
+	}
+
+	return -1;
+}
+
+U_BOOT_CMD(
+	zboot, 2, 0,	do_zboot,
+	"Boot bzImage",
+	""
+);