LXR linux/arch/ia64/hp/sim/boot/bootloader.c

   1/*
   2 * arch/ia64/hp/sim/boot/bootloader.c
   3 *
   4 * Loads an ELF kernel.
   5 *
   6 * Copyright (C) 1998-2003 Hewlett-Packard Co
   7 *      David Mosberger-Tang <davidm@hpl.hp.com>
   8 *      Stephane Eranian <eranian@hpl.hp.com>
   9 *
  10 * 01/07/99 S.Eranian modified to pass command line arguments to kernel
  11 */
  12struct task_struct;     /* forward declaration for elf.h */
  13
  14#include <linux/elf.h>
  15#include <linux/init.h>
  16#include <linux/kernel.h>
  17
  18#include <asm/elf.h>
  19#include <asm/intrinsics.h>
  20#include <asm/pal.h>
  21#include <asm/pgtable.h>
  22#include <asm/sal.h>
  23
  24#include "ssc.h"
  25
  26struct disk_req {
  27        unsigned long addr;
  28        unsigned len;
  29};
  30
  31struct disk_stat {
  32        int fd;
  33        unsigned count;
  34};
  35
  36extern void jmp_to_kernel (unsigned long bp, unsigned long e_entry);
  37extern struct ia64_boot_param *sys_fw_init (const char *args, int arglen);
  38extern void debug_break (void);
  39
  40static void
  41cons_write (const char *buf)
  42{
  43        unsigned long ch;
  44
  45        while ((ch = *buf++) != '\0') {
  46                ssc(ch, 0, 0, 0, SSC_PUTCHAR);
  47                if (ch == '\n')
  48                  ssc('\r', 0, 0, 0, SSC_PUTCHAR);
  49        }
  50}
  51
  52#define MAX_ARGS 32
  53
  54void
  55start_bootloader (void)
  56{
  57        static char mem[4096];
  58        static char buffer[1024];
  59        unsigned long off;
  60        int fd, i;
  61        struct disk_req req;
  62        struct disk_stat stat;
  63        struct elfhdr *elf;
  64        struct elf_phdr *elf_phdr;      /* program header */
  65        unsigned long e_entry, e_phoff, e_phnum;
  66        register struct ia64_boot_param *bp;
  67        char *kpath, *args;
  68        long arglen = 0;
  69
  70        ssc(0, 0, 0, 0, SSC_CONSOLE_INIT);
  71
  72        /*
  73         * S.Eranian: extract the commandline argument from the simulator
  74         *
  75         * The expected format is as follows:
  76         *
  77         *      kernelname args...
  78         *
  79         * Both are optional but you can't have the second one without the first.
  80         */
  81        arglen = ssc((long) buffer, 0, 0, 0, SSC_GET_ARGS);
  82
  83        kpath = "vmlinux";
  84        args = buffer;
  85        if (arglen > 0) {
  86                kpath = buffer;
  87                while (*args != ' ' && *args != '\0')
  88                        ++args, --arglen;
  89                if (*args == ' ')
  90                        *args++ = '\0', --arglen;
  91        }
  92
  93        if (arglen <= 0) {
  94                args = "";
  95                arglen = 1;
  96        }
  97
  98        fd = ssc((long) kpath, 1, 0, 0, SSC_OPEN);
  99
 100        if (fd < 0) {
 101                cons_write(kpath);
 102                cons_write(": file not found, reboot now\n");
 103                for(;;);
 104        }
 105        stat.fd = fd;
 106        off = 0;
 107
 108        req.len = sizeof(mem);
 109        req.addr = (long) mem;
 110        ssc(fd, 1, (long) &req, off, SSC_READ);
 111        ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 112
 113        elf = (struct elfhdr *) mem;
 114        if (elf->e_ident[0] == 0x7f && strncmp(elf->e_ident + 1, "ELF", 3) != 0) {
 115                cons_write("not an ELF file\n");
 116                return;
 117        }
 118        if (elf->e_type != ET_EXEC) {
 119                cons_write("not an ELF executable\n");
 120                return;
 121        }
 122        if (!elf_check_arch(elf)) {
 123                cons_write("kernel not for this processor\n");
 124                return;
 125        }
 126
 127        e_entry = elf->e_entry;
 128        e_phnum = elf->e_phnum;
 129        e_phoff = elf->e_phoff;
 130
 131        cons_write("loading ");
 132        cons_write(kpath);
 133        cons_write("...\n");
 134
 135        for (i = 0; i < e_phnum; ++i) {
 136                req.len = sizeof(*elf_phdr);
 137                req.addr = (long) mem;
 138                ssc(fd, 1, (long) &req, e_phoff, SSC_READ);
 139                ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 140                if (stat.count != sizeof(*elf_phdr)) {
 141                        cons_write("failed to read phdr\n");
 142                        return;
 143                }
 144                e_phoff += sizeof(*elf_phdr);
 145
 146                elf_phdr = (struct elf_phdr *) mem;
 147
 148                if (elf_phdr->p_type != PT_LOAD)
 149                        continue;
 150
 151                req.len = elf_phdr->p_filesz;
 152                req.addr = __pa(elf_phdr->p_paddr);
 153                ssc(fd, 1, (long) &req, elf_phdr->p_offset, SSC_READ);
 154                ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 155                memset((char *)__pa(elf_phdr->p_paddr) + elf_phdr->p_filesz, 0,
 156                       elf_phdr->p_memsz - elf_phdr->p_filesz);
 157        }
 158        ssc(fd, 0, 0, 0, SSC_CLOSE);
 159
 160        cons_write("starting kernel...\n");
 161
 162        /* fake an I/O base address: */
 163        ia64_setreg(_IA64_REG_AR_KR0, 0xffffc000000UL);
 164
 165        bp = sys_fw_init(args, arglen);
 166
 167        ssc(0, (long) kpath, 0, 0, SSC_LOAD_SYMBOLS);
 168
 169        debug_break();
 170        jmp_to_kernel((unsigned long) bp, e_entry);
 171
 172        cons_write("kernel returned!\n");
 173        ssc(-1, 0, 0, 0, SSC_EXIT);
 174}
 175