1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/ia64/hp/sim/boot/bootloader.c
4 *
5 * Loads an ELF kernel.
6 *
7 * Copyright (C) 1998-2003 Hewlett-Packard Co
8 * David Mosberger-Tang <davidm@hpl.hp.com>
9 * Stephane Eranian <eranian@hpl.hp.com>
10 *
11 * 01/07/99 S.Eranian modified to pass command line arguments to kernel
12 */
13 struct task_struct; /* forward declaration for elf.h */
14
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
25 #include "ssc.h"
26
27 struct disk_req {
28 unsigned long addr;
29 unsigned len;
30 };
31
32 struct disk_stat {
33 int fd;
34 unsigned count;
35 };
36
37 extern void jmp_to_kernel (unsigned long bp, unsigned long e_entry);
38 extern struct ia64_boot_param *sys_fw_init (const char *args, int arglen);
39 extern void debug_break (void);
40
41 static void
cons_write(const char * buf)42 cons_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
55 void
start_bootloader(void)56 start_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
