/* * Originally adapted by Gary Thomas. Much additional work by * Cort Dougan . On top of that still more work by * Dan Malek . * * Currently maintained by: Tom Rini * * 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 #include #include #include #include #include #include #include #include #include #include #include "nonstdio.h" #include "zlib.h" #if defined(CONFIG_SERIAL_CONSOLE) || defined(CONFIG_VGA_CONSOLE) #define INTERACTIVE_CONSOLE 1 #endif /* The linker tells us where the image is. */ extern char __image_begin, __image_end; extern char __ramdisk_begin, __ramdisk_end; extern char _end[]; /* 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 (usually board info). * On these boards, we grab some known memory holes to hold this information. */ char cmd_buf[256]; char *cmd_line = cmd_buf; char *avail_ram; char *end_avail; char *zimage_start; /* This is for 4xx treeboot. It provides a place for the bootrom * give us a pointer to a rom environment command line. */ char *bootrom_cmdline = ""; /* 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 ip=on"; /* Serial port to use. */ unsigned long com_port; /* We need to make sure that this is before the images to ensure * that it's in a mapped location. - Tom */ bd_t hold_resid_buf __attribute__ ((__section__ (".data.boot"))); bd_t *hold_residual = &hold_resid_buf; extern unsigned long serial_init(int chan, bd_t *bp); extern void serial_close(unsigned long com_port); extern unsigned long start; extern void flush_instruction_cache(void); extern void gunzip(void *, int, unsigned char *, int *); extern void embed_config(bd_t **bp); /* Weak function for boards which don't need to build the * board info struct because they are using PPCBoot/U-Boot. */ void __attribute__ ((weak)) embed_config(bd_t **bdp) { } unsigned long load_kernel(unsigned long load_addr, int num_words, unsigned long cksum, bd_t *bp) { #ifdef INTERACTIVE_CONSOLE int timer = 0; char ch; #endif char *cp; int zimage_size; unsigned long initrd_size; /* First, capture the embedded board information. Then * initialize the serial console port. */ embed_config(&bp); com_port = serial_init(0, bp); /* 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("\nloaded 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("\nrelocated to: "); puthex((unsigned long)hold_residual); puts(" "); puthex((unsigned long)((unsigned long)hold_residual + sizeof(bd_t))); puts("\n"); } /* * We link ourself to an arbitrary low address. When we run, we * relocate outself to that address. __image_being points to * the part of the image where the zImage is. -- Tom */ zimage_start = (char *)(unsigned long)(&__image_begin); zimage_size = (unsigned long)(&__image_end) - (unsigned long)(&__image_begin); initrd_size = (unsigned long)(&__ramdisk_end) - (unsigned long)(&__ramdisk_begin); /* * The zImage and initrd will be between start and _end, so they've * already been moved once. We're good to go now. -- Tom */ puts("zimage at: "); puthex((unsigned long)zimage_start); puts(" "); puthex((unsigned long)(zimage_size+zimage_start)); puts("\n"); if ( initrd_size ) { puts("initrd at: "); puthex((unsigned long)(&__ramdisk_begin)); puts(" "); puthex((unsigned long)(&__ramdisk_end));puts("\n"); } /* * setup avail_ram - this is the first part of ram usable * by the uncompress code. Anything after this program in RAM * is now fair game. -- Tom */ avail_ram = (char *)PAGE_ALIGN((unsigned long)_end); puts("avail ram: "); puthex((unsigned long)avail_ram); puts(" "); puthex((unsigned long)end_avail); puts("\n"); puts("\nLinux/PPC load: "); 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_size ) memcpy (cmd_line, ramroot_string, sizeof(ramroot_string)); else memcpy (cmd_line, netroot_string, sizeof(netroot_string)); #endif while ( *cp ) putc(*cp++); #ifdef INTERACTIVE_CONSOLE /* * If they have a console, allow them to edit the command line. * Otherwise, don't bother wasting the five seconds. */ 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 */ } #endif *cp = 0; puts("\nUncompressing Linux..."); gunzip(0, 0x400000, zimage_start, &zimage_size); flush_instruction_cache(); puts("done.\n"); { struct bi_record *rec; unsigned long initrd_loc; unsigned long rec_loc = _ALIGN((unsigned long)(zimage_size) + (1 << 20) - 1, (1 << 20)); rec = (struct bi_record *)rec_loc; /* We need to make sure that the initrd and bi_recs do not * overlap. */ if ( initrd_size ) { initrd_loc = (unsigned long)(&__ramdisk_begin); /* If the bi_recs are in the middle of the current * initrd, move the initrd to the next MB * boundary. */ if ((rec_loc > initrd_loc) && ((initrd_loc + initrd_size) > rec_loc)) { initrd_loc = _ALIGN((unsigned long)(zimage_size) + (2 << 20) - 1, (2 << 20)); memmove((void *)initrd_loc, &__ramdisk_begin, initrd_size); puts("initrd moved: "); puthex(initrd_loc); puts(" "); puthex(initrd_loc + initrd_size); puts("\n"); } } rec->tag = BI_FIRST; rec->size = sizeof(struct bi_record); rec = (struct bi_record *)((unsigned long)rec + rec->size); rec->tag = BI_CMD_LINE; memcpy( (char *)rec->data, cmd_line, strlen(cmd_line)+1); rec->size = sizeof(struct bi_record) + strlen(cmd_line) + 1; rec = (struct bi_record *)((unsigned long)rec + rec->size); if ( initrd_size ) { rec->tag = BI_INITRD; rec->data[0] = initrd_loc; rec->data[1] = initrd_size; rec->size = sizeof(struct bi_record) + 2 * sizeof(unsigned long); rec = (struct bi_record *)((unsigned long)rec + rec->size); } rec->tag = BI_LAST; rec->size = sizeof(struct bi_record); rec = (struct bi_record *)((unsigned long)rec + rec->size); } puts("Now booting the kernel\n"); serial_close(com_port); return (unsigned long)hold_residual; }