From 2262cfeef91458b01a1bfe3812ccbbfdf8b82807 Mon Sep 17 00:00:00 2001 From: wdenk Date: Mon, 18 Nov 2002 00:14:45 +0000 Subject: * Patch by Daniel Engström, 13 Nov 2002: Add support for i386 architecture and AMD SC520 board MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * Patch by Pierre Aubert, 12 Nov 2002: Add support for DOS filesystem and booting from DOS floppy disk --- lib_i386/zimage.c | 276 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 276 insertions(+) create mode 100644 lib_i386/zimage.c (limited to 'lib_i386/zimage.c') diff --git a/lib_i386/zimage.c b/lib_i386/zimage.c new file mode 100644 index 000000000..190d46ef7 --- /dev/null +++ b/lib_i386/zimage.c @@ -0,0 +1,276 @@ +/* + * (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 i386 zImage and bzImage loading + * + * based on the procdure described in + * linux/Documentation/i386/boot.txt + */ + +#include +#include +#include +#include +#include +#include + +/* + * 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; + + + setup_base = (void*)DEFAULT_SETUP_BASE; /* base address for real-mode segment */ + + if (KERNEL_MAGIC != *(u16*)(image + BOOT_FLAG_OFF)) { + printf("Error: Invalid kernel magic (found 0x%04x, expected 0xaa55)\n", + *(u16*)(image + BOOT_FLAG_OFF)); + return 0; + } + + + /* determine boot protocol version */ + if (KERNEL_V2_MAGIC == *(u32*)(image+HEADER_OFF)) { + bootproto = *(u16*)(image+VERSION_OFF); + } else { + /* Very old kernel */ + bootproto = 0x0100; + } + + /* determine size of setup */ + if (0 == *(u8*)(image + SETUP_SECTS_OFF)) { + setup_size = 5 * 512; + } else { + setup_size = (*(u8*)(image + SETUP_SECTS_OFF) + 1) * 512; + } + + if (setup_size > SETUP_MAX_SIZE) { + printf("Error: Setup is too large (%d bytes)\n", setup_size); + } + + /* Determine image type */ + big_image = (bootproto >= 0x0200) && (*(u8*)(image + LOADFLAGS_OFF) & BIG_KERNEL_FLAG); + + /* Derermine load address */ + load_address = (void*)(big_image ? BZIMAGE_LOAD_ADDR:ZIMAGE_LOAD_ADDR); + + /* load setup */ + 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); + } + + if (bootproto >= 0x0200) { + *(u8*)(setup_base + TYPE_OF_LOADER_OFF) = 0xff; + printf("Linux kernel version %s\n", + (char*)(setup_base + SETUP_START_OFFSET + + *(u16*)(setup_base + START_SYS_OFF + 2))); + + if (initrd_addr) { + printf("Initial RAM disk at linear address 0x%08lx, size %ld bytes\n", + initrd_addr, initrd_size); + + *(u32*)(setup_base + RAMDISK_IMAGE_OFF) = initrd_addr; + *(u32*)(setup_base + RAMDISK_SIZE_OFF)=initrd_size; + } + } + + if (bootproto >= 0x0201) { + *(u16*)(setup_base + HEAP_END_PTR_OFF) = HEAP_END_OFFSET; + + /* CAN_USE_HEAP */ + *(u8*)(setup_base + LOADFLAGS_OFF) = + *(u8*)(setup_base + LOADFLAGS_OFF) | HEAP_FLAG; + } + + if (bootproto >= 0x0202) { + *(u32*)(setup_base + CMD_LINE_PTR_OFF) = (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; + *(u16*)(setup_base + SETUP_MOVE_SIZE_OFF) = 0x9100; + } + + + + if (big_image) { + if ((kernel_size - setup_size) > BZIMAGE_MAX_SIZE) { + printf("Error: bzImage kernel too big! (size: %ld, max: %d)\n", + kernel_size - setup_size, BZIMAGE_MAX_SIZE); + return 0; + } + + } else if ((kernel_size - setup_size) > ZIMAGE_MAX_SIZE) { + printf("Error: zImage kernel too big! (size: %ld, max: %d)\n", + kernel_size - setup_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 - setup_size); + + + memmove(load_address, image + setup_size, kernel_size - setup_size); + + /* ready for booting */ + return setup_base; +} + + +void boot_zimage(void *setup_base) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(struct pt_regs)); + regs.xds = (u32)setup_base >> 4; + regs.xss = 0x8e00; + regs.esp = 0x200; + regs.eflags = 0; + enter_realmode(((u32)setup_base+SETUP_START_OFFSET)>>4, 0, ®s, ®s); +} + + +image_header_t *fake_zimage_header(image_header_t *hdr, void *ptr, int size) +{ + /* There is no way to know the size of a zImage ... * + * so we assume that 2MB will be enough for now */ +#define ZIMAGE_SIZE 0x200000 + + /* load a 1MB, the loaded will have to be moved to its final + * position again later... */ +#define ZIMAGE_LOAD 0x100000 + + ulong checksum; + + if (KERNEL_MAGIC != *(u16*)(ptr + BOOT_FLAG_OFF)) { + /* not a zImage or bzImage */ + return NULL; + } + + if (-1 == size) { + size = ZIMAGE_SIZE; + } +#if 0 + checksum = crc32 (0, ptr, size); +#else + checksum = 0; +#endif + memset(hdr, 0, sizeof(image_header_t)); + + /* Build new header */ + hdr->ih_magic = htonl(IH_MAGIC); + hdr->ih_time = 0; + hdr->ih_size = htonl(size); + hdr->ih_load = htonl(ZIMAGE_LOAD); + hdr->ih_ep = 0; + hdr->ih_dcrc = htonl(checksum); + hdr->ih_os = IH_OS_LINUX; + hdr->ih_arch = IH_CPU_I386; + hdr->ih_type = IH_TYPE_KERNEL; + hdr->ih_comp = IH_COMP_NONE; + + strncpy((char *)hdr->ih_name, "(none)", IH_NMLEN); + + checksum = crc32(0,(const char *)hdr,sizeof(image_header_t)); + + hdr->ih_hcrc = htonl(checksum); + + return hdr; +} -- cgit v1.2.3