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/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
  26 struct disk_req {
  27         unsigned long addr;
  28         unsigned len;
  29 };
  30
  31 struct disk_stat {
  32         int fd;
  33         unsigned count;
  34 };
  35
  36 extern void jmp_to_kernel (unsigned long bp, unsigned long e_entry);
  37 extern struct ia64_boot_param *sys_fw_init (const char *args, int arglen);
  38 extern void debug_break (void);
  39
  40 static void
  41 cons_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
  54 void
  55 start_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 }