11913091 |
1 | // vim:shiftwidth=2:expandtab |
2 | #include <stdio.h> |
3 | #include <stdlib.h> |
4 | #include <sys/types.h> |
5 | #include <sys/stat.h> |
6 | #include <fcntl.h> |
7 | #include <sys/mman.h> |
8 | #include <sys/types.h> |
9 | #include <unistd.h> |
10 | #include <signal.h> |
11 | #include <asm/ucontext.h> |
12 | |
13 | #include "header.h" |
86418a84 |
14 | #include "sys_cacheflush.h" |
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15 | |
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16 | //#define iolog printf |
17 | #define iolog(...) |
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18 | |
19 | typedef unsigned int u32; |
20 | typedef unsigned short u16; |
21 | typedef unsigned char u8; |
22 | |
23 | static int memdev; |
24 | static volatile u16 *memregs, *blitter; |
25 | |
26 | |
27 | static volatile void *translate_addr(u32 a, u32 *mask) |
28 | { |
29 | if ((a & 0xfff00000) == 0x7f000000) { |
30 | *mask = 0xffff; |
31 | return memregs; |
32 | } |
33 | if ((a & 0xfff00000) == 0x7f100000) { |
34 | *mask = 0xff; |
35 | return blitter; |
36 | } |
37 | fprintf(stderr, "bad IO @ %08x\n", a); |
38 | abort(); |
39 | } |
40 | |
41 | static u32 xread8(u32 a) |
42 | { |
43 | volatile u8 *mem; |
44 | u32 mask; |
45 | |
46 | iolog("r8 %08x\n", a); |
47 | mem = translate_addr(a, &mask); |
48 | return mem[a & mask]; |
49 | } |
50 | |
51 | static u32 xread16(u32 a) |
52 | { |
53 | volatile u16 *mem; |
54 | u32 mask; |
55 | |
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56 | //if ((a & 0xfff00000) == 0x7f100000) { static int a; a ^= ~1; return a & 0xffff; } |
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57 | iolog("r16 %08x\n", a); |
58 | mem = translate_addr(a, &mask); |
59 | return mem[(a & mask) / 2]; |
60 | } |
61 | |
62 | static u32 xread32(u32 a) |
63 | { |
64 | volatile u32 *mem; |
65 | u32 mask; |
66 | |
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67 | //if ((a & 0xfff00000) == 0x7f100000) { static int a; a ^= ~1; return a; } |
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68 | iolog("r32 %08x\n", a); |
69 | mem = translate_addr(a, &mask); |
70 | return mem[(a & mask) / 4]; |
71 | } |
72 | |
73 | static void xwrite8(u32 a, u32 d) |
74 | { |
75 | volatile u8 *mem; |
76 | u32 mask; |
77 | |
78 | iolog("w8 %08x %08x\n", a, d); |
79 | mem = translate_addr(a, &mask); |
80 | mem[a & mask] = d; |
81 | } |
82 | |
83 | static void xwrite16(u32 a, u32 d) |
84 | { |
85 | volatile u16 *mem; |
86 | u32 mask; |
87 | |
88 | iolog("w16 %08x %08x\n", a, d); |
89 | mem = translate_addr(a, &mask); |
90 | mem[(a & mask) / 2] = d; |
91 | } |
92 | |
93 | static void xwrite32(u32 a, u32 d) |
94 | { |
95 | volatile u32 *mem; |
96 | u32 mask; |
97 | |
98 | iolog("w32 %08x %08x\n", a, d); |
99 | mem = translate_addr(a, &mask); |
100 | mem[(a & mask) / 4] = d; |
101 | } |
102 | |
103 | #define BIT_SET(v, b) (v & (1 << (b))) |
104 | |
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105 | static void handle_op(u32 pc, u32 op, u32 *regs, u32 addr_check) |
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106 | { |
107 | u32 t, shift, ret, addr; |
108 | int rn, rd; |
109 | |
110 | rd = (op & 0x0000f000) >> 12; |
111 | rn = (op & 0x000f0000) >> 16; |
112 | |
113 | if ((op & 0x0f200090) == 0x01000090) { // AM3: LDRH, STRH |
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114 | if (!BIT_SET(op, 5)) // !H |
115 | goto unhandled; |
116 | if (BIT_SET(op, 6) && !BIT_SET(op, 20)) // S && !L |
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117 | goto unhandled; |
118 | |
119 | if (BIT_SET(op, 22)) // imm offset |
120 | t = ((op & 0xf00) >> 4) | (op & 0x0f); |
121 | else // reg offset |
122 | t = regs[op & 0x000f]; |
123 | |
124 | if (!BIT_SET(op, 23)) |
125 | t = -t; |
126 | addr = regs[rn] + t; |
127 | |
128 | if (BIT_SET(op, 20)) { // Load |
129 | ret = xread16(addr); |
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130 | if (BIT_SET(op, 6)) { // S |
131 | ret <<= 16; |
132 | ret = (signed int)ret >> 16; |
133 | } |
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134 | regs[rd] = ret; |
135 | } |
136 | else |
137 | xwrite16(addr, regs[rd]); |
138 | } |
139 | else if ((op & 0x0d200000) == 0x05000000) { // AM2: LDR[B], STR[B] |
140 | if (BIT_SET(op, 25)) { // reg offs |
141 | if (BIT_SET(op, 4)) |
142 | goto unhandled; |
143 | |
144 | t = regs[op & 0x000f]; |
145 | shift = (op & 0x0f80) >> 7; |
146 | switch ((op & 0x0060) >> 5) { |
147 | case 0: t = t << shift; break; |
148 | case 1: t = t >> (shift + 1); break; |
149 | case 2: t = (signed int)t >> (shift + 1); break; |
150 | case 3: goto unhandled; // I'm just lazy |
151 | } |
152 | } |
153 | else // imm offs |
154 | t = op & 0x0fff; |
155 | |
156 | if (!BIT_SET(op, 23)) |
157 | t = -t; |
158 | addr = regs[rn] + t; |
159 | |
160 | if (BIT_SET(op, 20)) { // Load |
161 | if (BIT_SET(op, 22)) // Byte |
162 | ret = xread8(addr); |
163 | else |
164 | ret = xread32(addr); |
165 | regs[rd] = ret; |
166 | } |
167 | else { |
168 | if (BIT_SET(op, 22)) // Byte |
169 | xwrite8(addr, regs[rd]); |
170 | else |
171 | xwrite32(addr, regs[rd]); |
172 | } |
173 | } |
174 | else |
175 | goto unhandled; |
176 | |
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177 | #if 0 |
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178 | if (addr != addr_check) { |
179 | fprintf(stderr, "bad calculated addr: %08x vs %08x\n", addr, addr_check); |
180 | abort(); |
181 | } |
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182 | #endif |
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183 | return; |
184 | |
185 | unhandled: |
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186 | fprintf(stderr, "unhandled IO op %08x @ %08x\n", op, pc); |
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187 | } |
188 | |
189 | #define LINKPAGE_SIZE 0x1000 |
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190 | #define LINKPAGE_COUNT 4 |
191 | #define LINKPAGE_ALLOC (LINKPAGE_SIZE * LINKPAGE_COUNT) |
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192 | |
193 | struct linkpage { |
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194 | u32 saved_regs[15]; |
195 | u32 *lp_r1; |
196 | void (*handler)(u32 addr_pc, u32 op, u32 *regs, u32 addr_check); |
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197 | u32 code[0]; |
198 | }; |
199 | |
200 | static struct linkpage *g_linkpage; |
201 | static u32 *g_code_ptr; |
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202 | static int g_linkpage_count; |
203 | |
204 | static void init_linkpage(void) |
205 | { |
206 | g_linkpage->lp_r1 = &g_linkpage->saved_regs[1]; |
207 | g_linkpage->handler = handle_op; |
208 | g_code_ptr = g_linkpage->code; |
209 | } |
210 | |
211 | static u32 make_offset12(u32 *pc, u32 *target) |
212 | { |
213 | int lp_offs, u = 1; |
214 | |
215 | lp_offs = (char *)target - (char *)pc - 2*4; |
216 | if (lp_offs < 0) { |
217 | lp_offs = -lp_offs; |
218 | u = 0; |
219 | } |
220 | if (lp_offs >= LINKPAGE_SIZE) { |
221 | fprintf(stderr, "linkpage too far: %d\n", lp_offs); |
222 | abort(); |
223 | } |
224 | |
225 | return (u << 23) | lp_offs; |
226 | } |
227 | |
228 | static u32 make_jmp(u32 *pc, u32 *target) |
229 | { |
230 | int jmp_val; |
231 | |
232 | jmp_val = target - pc - 2; |
233 | if (jmp_val < (int)0xff000000 || jmp_val > 0x00ffffff) { |
234 | fprintf(stderr, "jump out of range (%p -> %p)\n", pc, target); |
235 | abort(); |
236 | } |
237 | |
238 | return 0xea000000 | (jmp_val & 0x00ffffff); |
239 | } |
240 | |
241 | static void emit_op(u32 op) |
242 | { |
243 | *g_code_ptr++ = op; |
244 | } |
245 | |
246 | static void emit_op_io(u32 op, u32 *target) |
247 | { |
248 | op |= make_offset12(g_code_ptr, target); |
249 | emit_op(op); |
250 | } |
251 | |
252 | static void segv_sigaction(int num, siginfo_t *info, void *ctx) |
253 | { |
254 | struct ucontext *context = ctx; |
255 | u32 *regs = (u32 *)&context->uc_mcontext.arm_r0; |
256 | u32 *pc = (u32 *)regs[15]; |
257 | u32 old_op = *pc; |
258 | u32 *pc_ptr, *old_op_ptr; |
259 | int lp_size; |
260 | |
261 | if (((regs[15] ^ (u32)&segv_sigaction) & 0xff000000) == 0 || // PC is in our segment or |
262 | (((regs[15] ^ (u32)g_linkpage) & ~(LINKPAGE_ALLOC - 1)) == 0)) // .. in linkpage |
263 | { |
264 | // real crash - time to die |
265 | printf("segv %d %p @ %08x\n", info->si_code, info->si_addr, regs[15]); |
266 | signal(num, SIG_DFL); |
267 | raise(num); |
268 | } |
269 | printf("segv %d %p @ %08x\n", info->si_code, info->si_addr, regs[15]); |
270 | |
271 | // spit PC and op |
272 | pc_ptr = g_code_ptr++; |
273 | old_op_ptr = g_code_ptr++; |
274 | *pc_ptr = (u32)pc; |
275 | *old_op_ptr = old_op; |
276 | |
277 | // emit jump to code ptr |
278 | *pc = make_jmp(pc, g_code_ptr); |
279 | |
280 | // generate code: |
281 | // TODO: our own stack |
282 | emit_op_io(0xe50f0000, &g_linkpage->saved_regs[0]); // str r0, [saved_regs[0]] @ save r0 |
283 | emit_op_io(0xe51f0000, (u32 *)&g_linkpage->lp_r1); // ldr r0, =lp_r1 |
284 | emit_op (0xe8807ffe); // stmia r0, {r1-r14} |
285 | emit_op (0xe2402004); // sub r2, r0, #4 |
286 | emit_op_io(0xe51f0000, pc_ptr); // ldr r0, =pc |
287 | emit_op_io(0xe51f1000, old_op_ptr); // ldr r1, =old_op |
288 | emit_op (0xe1a04002); // mov r4, r2 |
289 | emit_op (0xe1a0e00f); // mov lr, pc |
290 | emit_op_io(0xe51ff000, (u32 *)&g_linkpage->handler); // ldr pc, =handle_op |
291 | emit_op (0xe8947fff); // ldmia r4, {r0-r14} |
292 | emit_op (make_jmp(g_code_ptr, pc + 1)); // jmp <back> |
293 | |
294 | // sync caches |
295 | sys_cacheflush(pc, pc + 1); |
296 | sys_cacheflush(g_linkpage, g_code_ptr); |
297 | |
298 | lp_size = (char *)g_code_ptr - (char *)g_linkpage; |
299 | printf("code #%d %d/%d\n", g_linkpage_count, lp_size, LINKPAGE_SIZE); |
300 | |
301 | if (lp_size + 13*4 > LINKPAGE_SIZE) { |
302 | g_linkpage_count++; |
303 | if (g_linkpage_count >= LINKPAGE_COUNT) { |
304 | fprintf(stderr, "too many linkpages needed\n"); |
305 | abort(); |
306 | } |
307 | g_linkpage = (void *)((char *)g_linkpage + LINKPAGE_SIZE); |
308 | init_linkpage(); |
309 | } |
310 | //handle_op(regs[15], op, regs, (u32)info->si_addr); |
311 | //regs[15] += 4; |
312 | } |
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313 | |
314 | void emu_init(void *map_bottom) |
315 | { |
316 | struct sigaction segv_action = { |
317 | .sa_sigaction = segv_sigaction, |
318 | .sa_flags = SA_SIGINFO, |
319 | }; |
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320 | void *ret; |
321 | |
322 | sigemptyset(&segv_action.sa_mask); |
323 | sigaction(SIGSEGV, &segv_action, NULL); |
324 | |
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325 | g_linkpage = (void *)(((u32)map_bottom - LINKPAGE_ALLOC) & ~0xfff); |
326 | ret = mmap(g_linkpage, LINKPAGE_ALLOC, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); |
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327 | if (ret != g_linkpage) { |
328 | perror("mmap linkpage"); |
329 | exit(1); |
330 | } |
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331 | printf("linkpages @ %p\n", g_linkpage); |
332 | init_linkpage(); |
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333 | |
334 | memdev = open("/dev/mem", O_RDWR); |
335 | memregs = mmap(NULL, 0x10000, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xc0000000); |
336 | blitter = mmap(NULL, 0x100, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xe0020000); |
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337 | //blitter = mmap(NULL, 0x100, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); |
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338 | printf("mapped %d %p %p\n", memdev, memregs, blitter); |
339 | } |
340 | |
341 | void *emu_mmap_dev(unsigned int length, int prot, int flags, unsigned int offset) |
342 | { |
343 | char name[32]; |
344 | int fd; |
345 | |
346 | if ((offset & ~0xffff) == 0xc0000000) { |
347 | return mmap((void *)0x7f000000, length, PROT_NONE, |
348 | MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0); |
349 | } |
350 | if ((offset & ~0xffff) == 0xe0020000) { |
351 | return mmap((void *)0x7f100000, length, PROT_NONE, |
352 | MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0); |
353 | } |
354 | // pass through |
355 | if ((offset & 0xfe000000) == 0x02000000) |
356 | return mmap(NULL, length, prot, flags, memdev, offset); |
357 | |
358 | sprintf(name, "m%08x", offset); |
359 | fd = open(name, O_CREAT|O_RDWR, 0644); |
360 | lseek(fd, length - 1, SEEK_SET); |
361 | name[0] = 0; |
362 | write(fd, name, 1); |
363 | |
364 | return mmap(NULL, length, prot, MAP_SHARED, fd, 0); |
365 | } |
366 | |