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/*
* Copyright (C) 2003 Stefan Reinauer
*
* See the file "COPYING" for further information about
* the copyright and warranty status of this work.
*/
#include "config.h"
#include "types.h"
#include "multiboot.h"
/* Multiboot: Check if the bit BIT in FLAGS is set. */
#define CHECK_FLAG(flags,bit) ((flags) & (1 << (bit)))
#ifdef DEBUG_CONSOLE
void cls(void);
void printk(const char *fmt, ...);
int uart_init(int port, unsigned long speed);
#endif
void legacybios(ucell romstart, ucell romend);
/* Check if MAGIC is valid and print the Multiboot information structure
pointed by ADDR. */
void cmain(unsigned long magic, unsigned long addr)
{
multiboot_info_t *mbi;
#ifdef DEBUG_CONSOLE
uart_init(SERIAL_PORT, SERIAL_SPEED);
/* Clear the screen. */
cls();
#endif
/* Am I booted by a Multiboot-compliant boot loader? */
if (magic != MULTIBOOT_BOOTLOADER_MAGIC) {
printk("legacybios: loader not multiboot capable\n");
return;
}
/* Set MBI to the address of the Multiboot information structure. */
mbi = (multiboot_info_t *) addr;
#ifdef DEBUG_BOOT
/* Print out the flags. */
printk("flags = 0x%x\n", mbi->flags);
/* Are mem_* valid? */
if (CHECK_FLAG(mbi->flags, 0))
printk("mem_lower = %dKB, mem_upper = %dKB\n",
mbi->mem_lower, mbi->mem_upper);
/* Is boot_device valid? */
if (CHECK_FLAG(mbi->flags, 1))
printk("boot_device = 0x%x\n", mbi->boot_device);
/* Is the command line passed? */
if (CHECK_FLAG(mbi->flags, 2))
printk("cmdline = %s\n", (char *) mbi->cmdline);
#endif
#ifdef DEBUG_BOOT
/* Bits 4 and 5 are mutually exclusive! */
if (CHECK_FLAG(mbi->flags, 4) && CHECK_FLAG(mbi->flags, 5)) {
printk("panic: binary claims to be a.out and elf.\n");
return;
}
#endif
/* Are mods_* valid? */
if (CHECK_FLAG(mbi->flags, 3)) {
module_t *mod;
unsigned int i;
#ifdef DEBUG_BOOT
printk("mods_count = %d, mods_addr = 0x%x\n",
mbi->mods_count, mbi->mods_addr);
#endif
for (i = 0, mod = (module_t *) mbi->mods_addr;
i < mbi->mods_count; i++, mod += sizeof(module_t)) {
legacybios(mod->mod_start, mod->mod_end);
#ifdef DEBUG_BOOT
printk
(" mod_start = 0x%x, mod_end = 0x%x, string = %s\n",
mod->mod_start, mod->mod_end,
(char *) mod->string);
#endif
}
}
return;
}
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