rev |
line source |
pascal@13691
|
1 #include <stdio.h>
|
pascal@13691
|
2 #include "iso9660.h"
|
pascal@13691
|
3
|
pascal@13691
|
4 static unsigned version;
|
pascal@13691
|
5 #define SETUPSECTORS 0x1F1
|
pascal@13691
|
6 #define ROFLAG 0x1F2
|
pascal@13691
|
7 #define SYSSIZE 0x1F4
|
pascal@13691
|
8 #define VIDEOMODE 0x1FA
|
pascal@13691
|
9 #define BOOTFLAG 0x1FE
|
pascal@13691
|
10 #define HEADER 0x202
|
pascal@13691
|
11 #define VERSION 0x206
|
pascal@13691
|
12 #define RMSWOFS 0x208
|
pascal@13691
|
13 #define RMSWSEG 0x20A
|
pascal@13691
|
14 #define LOADERTYPE 0x210
|
pascal@13691
|
15 #define LOADFLAGS 0x211
|
pascal@13691
|
16 #define SYSTEMCODE 0x214
|
pascal@13691
|
17 #define INITRDCODE 0x218
|
pascal@13691
|
18 #define INITRDSIZE 0x21C
|
pascal@13691
|
19 #define HEAPPTR 0x224
|
pascal@13691
|
20 #define CMDLINE 0x228
|
pascal@13691
|
21
|
pascal@13691
|
22 #define SETUP_SEGMENT 0x9000
|
pascal@13691
|
23 #define CMDLINE_OFFSET 0x9E00
|
pascal@13691
|
24
|
pascal@13691
|
25 #define BUFFERSZ 2*1024
|
pascal@13691
|
26 static char buffer[BUFFERSZ];
|
pascal@13691
|
27 static unsigned long initrd_addr, initrd_size;
|
pascal@13691
|
28
|
pascal@13691
|
29 static int may_exit_dos = 1;
|
pascal@13691
|
30 static void die(char *msg)
|
pascal@13691
|
31 {
|
pascal@13691
|
32 printf("%s.\n", msg);
|
pascal@13691
|
33 if (may_exit_dos)
|
pascal@13691
|
34 exit(1);
|
pascal@13691
|
35 while (1);
|
pascal@13691
|
36 }
|
pascal@13691
|
37
|
pascal@13691
|
38 static int vm86(void)
|
pascal@13691
|
39 {
|
pascal@13691
|
40 #asm
|
pascal@13691
|
41 smsw ax
|
pascal@13691
|
42 and ax, #1 // 0:realmode 1:vm86
|
pascal@13691
|
43 #endasm
|
pascal@13691
|
44 }
|
pascal@13691
|
45
|
pascal@13691
|
46 static struct mem {
|
pascal@13691
|
47 unsigned long base;
|
pascal@13691
|
48 int align;
|
pascal@13691
|
49 } kernelmem = { 0x100000, 0 };
|
pascal@13691
|
50
|
pascal@13691
|
51 #define initrdmem kernelmem
|
pascal@13691
|
52
|
pascal@13691
|
53 static void movehi(void)
|
pascal@13691
|
54 {
|
pascal@13691
|
55 #asm
|
pascal@13691
|
56 pusha
|
pascal@13691
|
57 xor di, di // 30
|
pascal@13691
|
58 mov cx, #9 // 2E..1E
|
pascal@13691
|
59 zero1:
|
pascal@13691
|
60 push di
|
pascal@13691
|
61 loop zero1
|
pascal@13691
|
62 push dword [_kernelmem] // 1A p->base
|
pascal@13691
|
63 push #-1 // 18
|
pascal@13691
|
64 push di // 16
|
pascal@13691
|
65 xor eax, eax
|
pascal@13691
|
66 cdq
|
pascal@13691
|
67 mov dx, ds
|
pascal@13691
|
68 shl edx, #4
|
pascal@13691
|
69 mov ax, #_buffer
|
pascal@13691
|
70 add edx, eax
|
pascal@13691
|
71 push edx // 12 linear_address(buffer)
|
pascal@13691
|
72 push #-1 // 10
|
pascal@13691
|
73 mov cl, #8 // 0E..00
|
pascal@13691
|
74 zero2:
|
pascal@13691
|
75 push di
|
pascal@13691
|
76 loop zero2
|
pascal@13691
|
77 mov ch, #BUFFERSZ/512
|
pascal@13691
|
78 push ss
|
pascal@13691
|
79 pop es
|
pascal@13691
|
80 mov si, sp
|
pascal@13691
|
81 mov ax, #0x8793
|
pascal@13691
|
82 mov [si+0x15], al
|
pascal@13691
|
83 xchg [si+0x1D], al
|
pascal@13691
|
84 mov [si+0x1F], al // bits 24..31, doesn't work for me :(
|
pascal@13691
|
85 int 0x15
|
pascal@13691
|
86 add sp, #0x30
|
pascal@13691
|
87 popa
|
pascal@13691
|
88 #endasm
|
pascal@13691
|
89 }
|
pascal@13691
|
90
|
pascal@13699
|
91 static int versiondos;
|
pascal@13699
|
92 static int dosversion(void)
|
pascal@13699
|
93 {
|
pascal@13699
|
94 #asm
|
pascal@13699
|
95 mov ah, #0x30
|
pascal@13699
|
96 int 0x21
|
pascal@13699
|
97 cbw
|
pascal@13699
|
98 mov _versiondos, ax
|
pascal@13699
|
99 #endasm
|
pascal@13699
|
100 }
|
pascal@13699
|
101
|
pascal@13691
|
102 static void load(struct mem *p, unsigned long size)
|
pascal@13691
|
103 {
|
pascal@13691
|
104 if (vm86())
|
pascal@13691
|
105 die("Need real mode");
|
pascal@13691
|
106 switch (p->align) {
|
pascal@13691
|
107 case 0: // kernel
|
pascal@13699
|
108 switch (dosversion()) {
|
pascal@13699
|
109 case 3: case 4: case 6: break;
|
pascal@13699
|
110 default:
|
pascal@13699
|
111 printf("DOS %d not supported.\nTrying anyway...\n",
|
pascal@13699
|
112 versiondos);
|
pascal@13699
|
113 }
|
pascal@13691
|
114 p->align = 4096;
|
pascal@13691
|
115 break;
|
pascal@13691
|
116 case 4096: // first initrd
|
pascal@13691
|
117 initrd_addr = p->base;
|
pascal@13691
|
118 p->align = 4;
|
pascal@13691
|
119 }
|
pascal@13691
|
120 while (size) {
|
pascal@13691
|
121 int n, s = sizeof(buffer);
|
pascal@13691
|
122 for (n = 0; n < s; n++) buffer[n] = 0;
|
pascal@13691
|
123 if (s > size) s = size;
|
pascal@13691
|
124 n = isoread(buffer, s);
|
pascal@13691
|
125 movehi();
|
pascal@13691
|
126 if (n != -1) {
|
pascal@13691
|
127 p->base += n;
|
pascal@13691
|
128 size -= n;
|
pascal@13691
|
129 }
|
pascal@13691
|
130 if (s != n) break;
|
pascal@13691
|
131 }
|
pascal@13691
|
132 initrd_size = p->base - initrd_addr;
|
pascal@13691
|
133 p->base += p->align - 1;
|
pascal@13691
|
134 p->base &= - p->align;
|
pascal@13691
|
135 }
|
pascal@13691
|
136
|
pascal@13691
|
137 static unsigned setupofs = 0;
|
pascal@13691
|
138
|
pascal@13691
|
139 void movesetup(void)
|
pascal@13691
|
140 {
|
pascal@13691
|
141 #asm
|
pascal@13691
|
142 pusha
|
pascal@13691
|
143 push #SETUP_SEGMENT
|
pascal@13691
|
144 pop es
|
pascal@13691
|
145 mov si, #_buffer
|
pascal@13691
|
146 mov di, _setupofs
|
pascal@13691
|
147 mov cx, #BUFFERSZ/2
|
pascal@13691
|
148 rep
|
pascal@13691
|
149 movsw
|
pascal@13691
|
150 mov _setupofs, di
|
pascal@13691
|
151 popa
|
pascal@13691
|
152 #endasm
|
pascal@13691
|
153 }
|
pascal@13691
|
154
|
pascal@13691
|
155 void loadkernel(void)
|
pascal@13691
|
156 {
|
pascal@13691
|
157 unsigned setup, n = BUFFERSZ;
|
pascal@13691
|
158 unsigned long syssize = 0;
|
pascal@13691
|
159
|
pascal@13691
|
160 do {
|
pascal@13691
|
161 isoread(buffer, n);
|
pascal@13691
|
162 if (setupofs == 0) {
|
pascal@13691
|
163 if (* (unsigned short *) (buffer + BOOTFLAG) != 0xAA55)
|
pascal@13691
|
164 die("The kernel is not bootable");
|
pascal@13691
|
165 setup = (1 + buffer[SETUPSECTORS]) << 9;
|
pascal@13691
|
166 if (setup == 512) setup = 5 << 9;
|
pascal@13691
|
167 syssize = * (unsigned long *) (buffer + SYSSIZE) << 4;
|
pascal@13691
|
168 version = * (unsigned short *) (buffer + VERSION);
|
pascal@13691
|
169 #define HDRS 0x53726448
|
pascal@13691
|
170 if (* (unsigned long *) (buffer + HEADER) != HDRS)
|
pascal@13691
|
171 version = 0;
|
pascal@13691
|
172 if (!version || !(buffer[LOADFLAGS] & 1)) {
|
pascal@13691
|
173 #undef ZIMAGE_SUPPORT /* Does not work... */
|
pascal@13691
|
174 #ifdef ZIMAGE_SUPPORT
|
pascal@13691
|
175 #asm
|
pascal@13691
|
176 pusha
|
pascal@13691
|
177 mov cx, #0x8000
|
pascal@13691
|
178 mov es, cx
|
pascal@13691
|
179 xor si, si
|
pascal@13691
|
180 xor di, di
|
pascal@13691
|
181 rep
|
pascal@13697
|
182 movsw // move 64K data
|
pascal@13691
|
183 push es
|
pascal@13691
|
184 pop ds
|
pascal@13691
|
185 push es
|
pascal@13691
|
186 pop ss
|
pascal@13697
|
187 mov ch, #0x70
|
pascal@13697
|
188 mov es, cx
|
pascal@13697
|
189 mov ch, #0x80
|
pascal@13697
|
190 rep
|
pascal@13697
|
191 seg cs
|
pascal@13697
|
192 movsw // move 64K code
|
pascal@13691
|
193 popa
|
pascal@13697
|
194 jmpi relocated, #0x7000
|
pascal@13691
|
195 relocated:
|
pascal@13691
|
196 #endasm
|
pascal@13691
|
197 kernelmem.base = 0x10000;
|
pascal@13697
|
198 if (syssize > 0x60000) /* 384K max */
|
pascal@13691
|
199 #endif
|
pascal@13691
|
200 die("Not a bzImage format");
|
pascal@13691
|
201 }
|
pascal@13691
|
202 if (version < 0x204)
|
pascal@13691
|
203 syssize &= 0x000FFFFFUL;
|
pascal@13691
|
204 if (version) {
|
pascal@13691
|
205 #ifdef REALMODE_SWITCH
|
pascal@13691
|
206 * (unsigned short *) (buffer + RMSWOFS) =
|
pascal@13691
|
207 realmode_switch;
|
pascal@13691
|
208 * (unsigned short *) (buffer + RMSWSEG) =
|
pascal@13691
|
209 getcs();
|
pascal@13691
|
210 #endif
|
pascal@13691
|
211 * (unsigned short *) (buffer + HEAPPTR) =
|
pascal@13691
|
212 0x9B00;
|
pascal@13691
|
213 // buffer[LOADFLAGS] |= 0x80;
|
pascal@13691
|
214 * (unsigned short *) (buffer + LOADERTYPE) |=
|
pascal@13691
|
215 0x80FF;
|
pascal@13691
|
216 }
|
pascal@13691
|
217 }
|
pascal@13691
|
218 movesetup();
|
pascal@13691
|
219 setup -= n;
|
pascal@13691
|
220 n = (setup > BUFFERSZ) ? BUFFERSZ : setup;
|
pascal@13691
|
221 } while (setup > 0);
|
pascal@13691
|
222
|
pascal@13691
|
223 load(&kernelmem, syssize);
|
pascal@13691
|
224 }
|
pascal@13691
|
225
|
pascal@13691
|
226 void loadinitrd(void)
|
pascal@13691
|
227 {
|
pascal@13691
|
228 if (version)
|
pascal@13691
|
229 load(&initrdmem, isofilesize);
|
pascal@13691
|
230 }
|
pascal@13691
|
231
|
pascal@13691
|
232 void bootlinux(char *cmdline)
|
pascal@13691
|
233 {
|
pascal@13691
|
234 #asm
|
pascal@13691
|
235 push #SETUP_SEGMENT
|
pascal@13691
|
236 pop es
|
pascal@13691
|
237 mov eax, _initrd_addr
|
pascal@13691
|
238 or eax, eax
|
pascal@13691
|
239 jz no_initrd
|
pascal@13691
|
240 mov di, #0x218
|
pascal@13691
|
241 stosd
|
pascal@13691
|
242 mov eax, _initrd_size
|
pascal@13691
|
243 stosd
|
pascal@13691
|
244 no_initrd:
|
pascal@13691
|
245 #endasm
|
pascal@13691
|
246 if (cmdline) {
|
pascal@13691
|
247 if (version <= 0x201) {
|
pascal@13691
|
248 #asm
|
pascal@13691
|
249 mov di, #0x0020
|
pascal@13691
|
250 mov ax, #0xA33F
|
pascal@13691
|
251 stosw
|
pascal@13691
|
252 mov ax, #CMDLINE_OFFSET
|
pascal@13691
|
253 stosw
|
pascal@13691
|
254 #endasm
|
pascal@13691
|
255 }
|
pascal@13691
|
256 else {
|
pascal@13691
|
257 #asm
|
pascal@13691
|
258 mov di, #0x0228
|
pascal@13691
|
259 mov eax, #SETUP_SEGMENT*16+CMDLINE_OFFSET
|
pascal@13691
|
260 stosd
|
pascal@13691
|
261 #endasm
|
pascal@13691
|
262 }
|
pascal@13691
|
263 #asm
|
pascal@13691
|
264 xchg ax, di
|
pascal@13691
|
265 mov si, .bootlinux.cmdline[bp]
|
pascal@13691
|
266 copy:
|
pascal@13691
|
267 lodsb
|
pascal@13691
|
268 stosb
|
pascal@13691
|
269 or al,al
|
pascal@13691
|
270 jne copy
|
pascal@13691
|
271 #endasm
|
pascal@13691
|
272 }
|
pascal@13691
|
273 #asm
|
pascal@13691
|
274 push es
|
pascal@13691
|
275 pop ds
|
pascal@13691
|
276 push ds
|
pascal@13691
|
277 pop ss
|
pascal@13691
|
278 mov sp, #CMDLINE_OFFSET
|
pascal@13691
|
279 jmpi 0, #0x9020
|
pascal@13691
|
280 #endasm
|
pascal@13691
|
281 }
|