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