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#include <asm/system.h>
  24
  25#include "ssc.h"
  26
  27struct disk_req {
  28        unsigned long addr;
  29        unsigned len;
  30};
  31
  32struct disk_stat {
  33        int fd;
  34        unsigned count;
  35};
  36
  37extern void jmp_to_kernel (unsigned long bp, unsigned long e_entry);
  38extern struct ia64_boot_param *sys_fw_init (const char *args, int arglen);
  39extern void debug_break (void);
  40
  41static void
  42cons_write (const char *buf)
  43{
  44        unsigned long ch;
  45
  46        while ((ch = *buf++) != '\0') {
  47                ssc(ch, 0, 0, 0, SSC_PUTCHAR);
  48                if (ch == '\n')
  49                  ssc('\r', 0, 0, 0, SSC_PUTCHAR);
  50        }
  51}
  52
  53#define MAX_ARGS 32
  54
  55void
  56start_bootloader (void)
  57{
  58        static char mem[4096];
  59        static char buffer[1024];
  60        unsigned long off;
  61        int fd, i;
  62        struct disk_req req;
  63        struct disk_stat stat;
  64        struct elfhdr *elf;
  65        struct elf_phdr *elf_phdr;      /* program header */
  66        unsigned long e_entry, e_phoff, e_phnum;
  67        register struct ia64_boot_param *bp;
  68        char *kpath, *args;
  69        long arglen = 0;
  70
  71        ssc(0, 0, 0, 0, SSC_CONSOLE_INIT);
  72
  73        /*
  74         * S.Eranian: extract the commandline argument from the simulator
  75         *
  76         * The expected format is as follows:
  77         *
  78         *      kernelname args...
  79         *
  80         * Both are optional but you can't have the second one without the first.
  81         */
  82        arglen = ssc((long) buffer, 0, 0, 0, SSC_GET_ARGS);
  83
  84        kpath = "vmlinux";
  85        args = buffer;
  86        if (arglen > 0) {
  87                kpath = buffer;
  88                while (*args != ' ' && *args != '\0')
  89                        ++args, --arglen;
  90                if (*args == ' ')
  91                        *args++ = '\0', --arglen;
  92        }
  93
  94        if (arglen <= 0) {
  95                args = "";
  96                arglen = 1;
  97        }
  98
  99        fd = ssc((long) kpath, 1, 0, 0, SSC_OPEN);
 100
 101        if (fd < 0) {
 102                cons_write(kpath);
 103                cons_write(": file not found, reboot now\n");
 104                for(;;);
 105        }
 106        stat.fd = fd;
 107        off = 0;
 108
 109        req.len = sizeof(mem);
 110        req.addr = (long) mem;
 111        ssc(fd, 1, (long) &req, off, SSC_READ);
 112        ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 113
 114        elf = (struct elfhdr *) mem;
 115        if (elf->e_ident[0] == 0x7f && strncmp(elf->e_ident + 1, "ELF", 3) != 0) {
 116                cons_write("not an ELF file\n");
 117                return;
 118        }
 119        if (elf->e_type != ET_EXEC) {
 120                cons_write("not an ELF executable\n");
 121                return;
 122        }
 123        if (!elf_check_arch(elf)) {
 124                cons_write("kernel not for this processor\n");
 125                return;
 126        }
 127
 128        e_entry = elf->e_entry;
 129        e_phnum = elf->e_phnum;
 130        e_phoff = elf->e_phoff;
 131
 132        cons_write("loading ");
 133        cons_write(kpath);
 134        cons_write("...\n");
 135
 136        for (i = 0; i < e_phnum; ++i) {
 137                req.len = sizeof(*elf_phdr);
 138                req.addr = (long) mem;
 139                ssc(fd, 1, (long) &req, e_phoff, SSC_READ);
 140                ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 141                if (stat.count != sizeof(*elf_phdr)) {
 142                        cons_write("failed to read phdr\n");
 143                        return;
 144                }
 145                e_phoff += sizeof(*elf_phdr);
 146
 147                elf_phdr = (struct elf_phdr *) mem;
 148
 149                if (elf_phdr->p_type != PT_LOAD)
 150                        continue;
 151
 152                req.len = elf_phdr->p_filesz;
 153                req.addr = __pa(elf_phdr->p_paddr);
 154                ssc(fd, 1, (long) &req, elf_phdr->p_offset, SSC_READ);
 155                ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 156                memset((char *)__pa(elf_phdr->p_paddr) + elf_phdr->p_filesz, 0,
 157                       elf_phdr->p_memsz - elf_phdr->p_filesz);
 158        }
 159        ssc(fd, 0, 0, 0, SSC_CLOSE);
 160
 161        cons_write("starting kernel...\n");
 162
 163        /* fake an I/O base address: */
 164        ia64_setreg(_IA64_REG_AR_KR0, 0xffffc000000UL);
 165
 166        bp = sys_fw_init(args, arglen);
 167
 168        ssc(0, (long) kpath, 0, 0, SSC_LOAD_SYMBOLS);
 169
 170        debug_break();
 171        jmp_to_kernel((unsigned long) bp, e_entry);
 172
 173        cons_write("kernel returned!\n");
 174        ssc(-1, 0, 0, 0, SSC_EXIT);
 175}
 176