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
cons_write(const char * buf)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
start_bootloader(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 }
175