1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
|
/*
* Originally adapted by Gary Thomas. Much additional work by
* Cort Dougan <cort@fsmlabs.com>. On top of that still more work by
* Dan Malek <dmalek@jlc.net>.
*
* Currently maintained by: Tom Rini <trini@kernel.crashing.org>
*/
#include <linux/types.h>
#include <linux/string.h>
#include <asm/bootinfo.h>
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/residual.h>
#if defined(CONFIG_4xx)
#include <asm/ibm4xx.h>
#elif defined(CONFIG_8xx)
#include <asm/mpc8xx.h>
#elif defined(CONFIG_8260)
#include <asm/mpc8260.h>
#endif
#include "nonstdio.h"
/* The linker tells us where the image is. */
extern char __image_begin, __image_end;
extern char __ramdisk_begin, __ramdisk_end;
extern char _end[];
/* Because of the limited amount of memory on embedded, it presents
* loading problems. The biggest is that we load this boot program
* into a relatively low memory address, and the Linux kernel Bss often
* extends into this space when it get loaded. When the kernel starts
* and zeros the BSS space, it also writes over the information we
* save here and pass to the kernel (usually board info).
* On these boards, we grab some known memory holes to hold this information.
*/
char cmd_buf[256];
char *cmd_line = cmd_buf;
char *avail_ram;
char *end_avail;
char *zimage_start;
/* This is for 4xx treeboot. It provides a place for the bootrom
* give us a pointer to a rom environment command line.
*/
char *bootrom_cmdline = "";
/* This is the default cmdline that will be given to the user at boot time..
* If none was specified at compile time, we'll give it one that should work.
* -- Tom */
#ifdef CONFIG_CMDLINE_BOOL
char compiled_string[] = CONFIG_CMDLINE;
#endif
char ramroot_string[] = "root=/dev/ram";
char netroot_string[] = "root=/dev/nfs rw ip=on";
/* Serial port to use. */
unsigned long com_port;
/* We need to make sure that this is before the images to ensure
* that it's in a mapped location. - Tom */
bd_t hold_resid_buf __attribute__ ((__section__ (".data.boot")));
bd_t *hold_residual = &hold_resid_buf;
extern unsigned long serial_init(int chan, bd_t *bp);
extern void serial_close(unsigned long com_port);
extern unsigned long start;
extern void flush_instruction_cache(void);
extern void gunzip(void *, int, unsigned char *, int *);
extern void embed_config(bd_t **bp);
/* Weak function for boards which don't need to build the
* board info struct because they are using PPCBoot/U-Boot.
*/
void __attribute__ ((weak))
embed_config(bd_t **bdp)
{
}
unsigned long
load_kernel(unsigned long load_addr, int num_words, unsigned long cksum, bd_t *bp)
{
char *cp, ch;
int timer = 0, zimage_size;
unsigned long initrd_size;
/* First, capture the embedded board information. Then
* initialize the serial console port.
*/
embed_config(&bp);
#if defined(CONFIG_SERIAL_CPM_CONSOLE) || defined(CONFIG_SERIAL_8250_CONSOLE)
com_port = serial_init(0, bp);
#endif
/* Grab some space for the command line and board info. Since
* we no longer use the ELF header, but it was loaded, grab
* that space.
*/
#ifdef CONFIG_MBX
/* Because of the way the MBX loads the ELF image, we can't
* tell where we started. We read a magic variable from the NVRAM
* that gives us the intermediate buffer load address.
*/
load_addr = *(uint *)0xfa000020;
load_addr += 0x10000; /* Skip ELF header */
#endif
/* copy board data */
if (bp)
memcpy(hold_residual,bp,sizeof(bd_t));
/* Set end of memory available to us. It is always the highest
* memory address provided by the board information.
*/
end_avail = (char *)(bp->bi_memsize);
puts("\nloaded at: "); puthex(load_addr);
puts(" "); puthex((unsigned long)(load_addr + (4*num_words))); puts("\n");
if ( (unsigned long)load_addr != (unsigned long)&start ) {
puts("relocated to: "); puthex((unsigned long)&start);
puts(" ");
puthex((unsigned long)((unsigned long)&start + (4*num_words)));
puts("\n");
}
if ( bp ) {
puts("board data at: "); puthex((unsigned long)bp);
puts(" ");
puthex((unsigned long)((unsigned long)bp + sizeof(bd_t)));
puts("\nrelocated to: ");
puthex((unsigned long)hold_residual);
puts(" ");
puthex((unsigned long)((unsigned long)hold_residual + sizeof(bd_t)));
puts("\n");
}
/*
* We link ourself to an arbitrary low address. When we run, we
* relocate outself to that address. __image_being points to
* the part of the image where the zImage is. -- Tom
*/
zimage_start = (char *)(unsigned long)(&__image_begin);
zimage_size = (unsigned long)(&__image_end) -
(unsigned long)(&__image_begin);
initrd_size = (unsigned long)(&__ramdisk_end) -
(unsigned long)(&__ramdisk_begin);
/*
* The zImage and initrd will be between start and _end, so they've
* already been moved once. We're good to go now. -- Tom
*/
puts("zimage at: "); puthex((unsigned long)zimage_start);
puts(" "); puthex((unsigned long)(zimage_size+zimage_start));
puts("\n");
if ( initrd_size ) {
puts("initrd at: ");
puthex((unsigned long)(&__ramdisk_begin));
puts(" "); puthex((unsigned long)(&__ramdisk_end));puts("\n");
}
/*
* setup avail_ram - this is the first part of ram usable
* by the uncompress code. Anything after this program in RAM
* is now fair game. -- Tom
*/
avail_ram = (char *)PAGE_ALIGN((unsigned long)_end);
puts("avail ram: "); puthex((unsigned long)avail_ram); puts(" ");
puthex((unsigned long)end_avail); puts("\n");
puts("\nLinux/PPC load: ");
cp = cmd_line;
/* This is where we try and pick the right command line for booting.
* If we were given one at compile time, use it. It Is Right.
* If we weren't, see if we have a ramdisk. If so, thats root.
* When in doubt, give them the netroot (root=/dev/nfs rw) -- Tom
*/
#ifdef CONFIG_CMDLINE_BOOL
memcpy (cmd_line, compiled_string, sizeof(compiled_string));
#else
if ( initrd_size )
memcpy (cmd_line, ramroot_string, sizeof(ramroot_string));
else
memcpy (cmd_line, netroot_string, sizeof(netroot_string));
#endif
while ( *cp )
putc(*cp++);
while (timer++ < 5*1000) {
if (tstc()) {
while ((ch = getc()) != '\n' && ch != '\r') {
if (ch == '\b' || ch == '\177') {
if (cp != cmd_line) {
cp--;
puts("\b \b");
}
} else if (ch == '\030' /* ^x */
|| ch == '\025') { /* ^u */
while (cp != cmd_line) {
cp--;
puts("\b \b");
}
} else {
*cp++ = ch;
putc(ch);
}
}
break; /* Exit 'timer' loop */
}
udelay(1000); /* 1 msec */
}
*cp = 0;
puts("\nUncompressing Linux...");
gunzip(0, 0x400000, zimage_start, &zimage_size);
flush_instruction_cache();
puts("done.\n");
{
struct bi_record *rec;
unsigned long initrd_loc = 0;
unsigned long rec_loc = _ALIGN((unsigned long)(zimage_size) +
(1 << 20) - 1, (1 << 20));
rec = (struct bi_record *)rec_loc;
/* We need to make sure that the initrd and bi_recs do not
* overlap. */
if ( initrd_size ) {
initrd_loc = (unsigned long)(&__ramdisk_begin);
/* If the bi_recs are in the middle of the current
* initrd, move the initrd to the next MB
* boundary. */
if ((rec_loc > initrd_loc) &&
((initrd_loc + initrd_size)
> rec_loc)) {
initrd_loc = _ALIGN((unsigned long)(zimage_size)
+ (2 << 20) - 1, (2 << 20));
memmove((void *)initrd_loc, &__ramdisk_begin,
initrd_size);
puts("initrd moved: "); puthex(initrd_loc);
puts(" "); puthex(initrd_loc + initrd_size);
puts("\n");
}
}
rec->tag = BI_FIRST;
rec->size = sizeof(struct bi_record);
rec = (struct bi_record *)((unsigned long)rec + rec->size);
rec->tag = BI_CMD_LINE;
memcpy( (char *)rec->data, cmd_line, strlen(cmd_line)+1);
rec->size = sizeof(struct bi_record) + strlen(cmd_line) + 1;
rec = (struct bi_record *)((unsigned long)rec + rec->size);
if ( initrd_size ) {
rec->tag = BI_INITRD;
rec->data[0] = initrd_loc;
rec->data[1] = initrd_size;
rec->size = sizeof(struct bi_record) + 2 *
sizeof(unsigned long);
rec = (struct bi_record *)((unsigned long)rec +
rec->size);
}
rec->tag = BI_LAST;
rec->size = sizeof(struct bi_record);
rec = (struct bi_record *)((unsigned long)rec + rec->size);
}
puts("Now booting the kernel\n");
#if defined(CONFIG_SERIAL_CPM_CONSOLE) || defined(CONFIG_SERIAL_8250_CONSOLE)
serial_close(com_port);
#endif
return (unsigned long)hold_residual;
}
|
