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  */
  12 struct task_struct;     /* forward declaration for elf.h */
  13
  14 #include <linux/config.h>
  15 #include <linux/elf.h>
  16 #include <linux/init.h>
  17 #include <linux/kernel.h>
  18
  19 #include <asm/elf.h>
  20 #include <asm/intrinsics.h>
  21 #include <asm/pal.h>
  22 #include <asm/pgtable.h>
  23 #include <asm/sal.h>
  24 #include <asm/system.h>
  25
  26 #include "ssc.h"
  27
  28 struct disk_req {
  29         unsigned long addr;
  30         unsigned len;
  31 };
  32
  33 struct disk_stat {
  34         int fd;
  35         unsigned count;
  36 };
  37
  38 extern void jmp_to_kernel (unsigned long bp, unsigned long e_entry);
  39 extern struct ia64_boot_param *sys_fw_init (const char *args, int arglen);
  40 extern void debug_break (void);
  41
  42 static void
  43 cons_write (const char *buf)
  44 {
  45         unsigned long ch;
  46
  47         while ((ch = *buf++) != '\0') {
  48                 ssc(ch, 0, 0, 0, SSC_PUTCHAR);
  49                 if (ch == '\n')
  50                   ssc('\r', 0, 0, 0, SSC_PUTCHAR);
  51         }
  52 }
  53
  54 #define MAX_ARGS 32
  55
  56 void
  57 start_bootloader (void)
  58 {
  59         static char mem[4096];
  60         static char buffer[1024];
  61         unsigned long off;
  62         int fd, i;
  63         struct disk_req req;
  64         struct disk_stat stat;
  65         struct elfhdr *elf;
  66         struct elf_phdr *elf_phdr;      /* program header */
  67         unsigned long e_entry, e_phoff, e_phnum;
  68         register struct ia64_boot_param *bp;
  69         char *kpath, *args;
  70         long arglen = 0;
  71
  72         ssc(0, 0, 0, 0, SSC_CONSOLE_INIT);
  73
  74         /*
  75          * S.Eranian: extract the commandline argument from the simulator
  76          *
  77          * The expected format is as follows:
  78          *
  79          *      kernelname args...
  80          *
  81          * Both are optional but you can't have the second one without the first.
  82          */
  83         arglen = ssc((long) buffer, 0, 0, 0, SSC_GET_ARGS);
  84
  85         kpath = "vmlinux";
  86         args = buffer;
  87         if (arglen > 0) {
  88                 kpath = buffer;
  89                 while (*args != ' ' && *args != '\0')
  90                         ++args, --arglen;
  91                 if (*args == ' ')
  92                         *args++ = '\0', --arglen;
  93         }
  94
  95         if (arglen <= 0) {
  96                 args = "";
  97                 arglen = 1;
  98         }
  99
 100         fd = ssc((long) kpath, 1, 0, 0, SSC_OPEN);
 101
 102         if (fd < 0) {
 103                 cons_write(kpath);
 104                 cons_write(": file not found, reboot now\n");
 105                 for(;;);
 106         }
 107         stat.fd = fd;
 108         off = 0;
 109
 110         req.len = sizeof(mem);
 111         req.addr = (long) mem;
 112         ssc(fd, 1, (long) &req, off, SSC_READ);
 113         ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 114
 115         elf = (struct elfhdr *) mem;
 116         if (elf->e_ident[0] == 0x7f && strncmp(elf->e_ident + 1, "ELF", 3) != 0) {
 117                 cons_write("not an ELF file\n");
 118                 return;
 119         }
 120         if (elf->e_type != ET_EXEC) {
 121                 cons_write("not an ELF executable\n");
 122                 return;
 123         }
 124         if (!elf_check_arch(elf)) {
 125                 cons_write("kernel not for this processor\n");
 126                 return;
 127         }
 128
 129         e_entry = elf->e_entry;
 130         e_phnum = elf->e_phnum;
 131         e_phoff = elf->e_phoff;
 132
 133         cons_write("loading ");
 134         cons_write(kpath);
 135         cons_write("...\n");
 136
 137         for (i = 0; i < e_phnum; ++i) {
 138                 req.len = sizeof(*elf_phdr);
 139                 req.addr = (long) mem;
 140                 ssc(fd, 1, (long) &req, e_phoff, SSC_READ);
 141                 ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 142                 if (stat.count != sizeof(*elf_phdr)) {
 143                         cons_write("failed to read phdr\n");
 144                         return;
 145                 }
 146                 e_phoff += sizeof(*elf_phdr);
 147
 148                 elf_phdr = (struct elf_phdr *) mem;
 149
 150                 if (elf_phdr->p_type != PT_LOAD)
 151                         continue;
 152
 153                 req.len = elf_phdr->p_filesz;
 154                 req.addr = __pa(elf_phdr->p_paddr);
 155                 ssc(fd, 1, (long) &req, elf_phdr->p_offset, SSC_READ);
 156                 ssc((long) &stat, 0, 0, 0, SSC_WAIT_COMPLETION);
 157                 memset((char *)__pa(elf_phdr->p_paddr) + elf_phdr->p_filesz, 0,
 158                        elf_phdr->p_memsz - elf_phdr->p_filesz);
 159         }
 160         ssc(fd, 0, 0, 0, SSC_CLOSE);
 161
 162         cons_write("starting kernel...\n");
 163
 164         /* fake an I/O base address: */
 165         ia64_setreg(_IA64_REG_AR_KR0, 0xffffc000000UL);
 166
 167         bp = sys_fw_init(args, arglen);
 168
 169         ssc(0, (long) kpath, 0, 0, SSC_LOAD_SYMBOLS);
 170
 171         debug_break();
 172         jmp_to_kernel((unsigned long) bp, e_entry);
 173
 174         cons_write("kernel returned!\n");
 175         ssc(-1, 0, 0, 0, SSC_EXIT);
 176 }