| 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" |
| 14 | |
| 15 | #define iolog printf |
| 16 | //#define iolog(...) |
| 17 | |
| 18 | typedef unsigned int u32; |
| 19 | typedef unsigned short u16; |
| 20 | typedef unsigned char u8; |
| 21 | |
| 22 | static int memdev; |
| 23 | static volatile u16 *memregs, *blitter; |
| 24 | |
| 25 | |
| 26 | static volatile void *translate_addr(u32 a, u32 *mask) |
| 27 | { |
| 28 | if ((a & 0xfff00000) == 0x7f000000) { |
| 29 | *mask = 0xffff; |
| 30 | return memregs; |
| 31 | } |
| 32 | if ((a & 0xfff00000) == 0x7f100000) { |
| 33 | *mask = 0xff; |
| 34 | return blitter; |
| 35 | } |
| 36 | fprintf(stderr, "bad IO @ %08x\n", a); |
| 37 | abort(); |
| 38 | } |
| 39 | |
| 40 | static u32 xread8(u32 a) |
| 41 | { |
| 42 | volatile u8 *mem; |
| 43 | u32 mask; |
| 44 | |
| 45 | iolog("r8 %08x\n", a); |
| 46 | mem = translate_addr(a, &mask); |
| 47 | return mem[a & mask]; |
| 48 | } |
| 49 | |
| 50 | static u32 xread16(u32 a) |
| 51 | { |
| 52 | volatile u16 *mem; |
| 53 | u32 mask; |
| 54 | |
| 55 | iolog("r16 %08x\n", a); |
| 56 | mem = translate_addr(a, &mask); |
| 57 | return mem[(a & mask) / 2]; |
| 58 | } |
| 59 | |
| 60 | static u32 xread32(u32 a) |
| 61 | { |
| 62 | volatile u32 *mem; |
| 63 | u32 mask; |
| 64 | |
| 65 | iolog("r32 %08x\n", a); |
| 66 | mem = translate_addr(a, &mask); |
| 67 | return mem[(a & mask) / 4]; |
| 68 | } |
| 69 | |
| 70 | static void xwrite8(u32 a, u32 d) |
| 71 | { |
| 72 | volatile u8 *mem; |
| 73 | u32 mask; |
| 74 | |
| 75 | iolog("w8 %08x %08x\n", a, d); |
| 76 | mem = translate_addr(a, &mask); |
| 77 | mem[a & mask] = d; |
| 78 | } |
| 79 | |
| 80 | static void xwrite16(u32 a, u32 d) |
| 81 | { |
| 82 | volatile u16 *mem; |
| 83 | u32 mask; |
| 84 | |
| 85 | iolog("w16 %08x %08x\n", a, d); |
| 86 | mem = translate_addr(a, &mask); |
| 87 | mem[(a & mask) / 2] = d; |
| 88 | } |
| 89 | |
| 90 | static void xwrite32(u32 a, u32 d) |
| 91 | { |
| 92 | volatile u32 *mem; |
| 93 | u32 mask; |
| 94 | |
| 95 | iolog("w32 %08x %08x\n", a, d); |
| 96 | mem = translate_addr(a, &mask); |
| 97 | mem[(a & mask) / 4] = d; |
| 98 | } |
| 99 | |
| 100 | #define BIT_SET(v, b) (v & (1 << (b))) |
| 101 | |
| 102 | static void handle_op(u32 addr_pc, u32 op, u32 *regs, u32 addr_check) |
| 103 | { |
| 104 | u32 t, shift, ret, addr; |
| 105 | int rn, rd; |
| 106 | |
| 107 | rd = (op & 0x0000f000) >> 12; |
| 108 | rn = (op & 0x000f0000) >> 16; |
| 109 | |
| 110 | if ((op & 0x0f200090) == 0x01000090) { // AM3: LDRH, STRH |
| 111 | if (BIT_SET(op, 6)) // S |
| 112 | goto unhandled; |
| 113 | |
| 114 | if (BIT_SET(op, 22)) // imm offset |
| 115 | t = ((op & 0xf00) >> 4) | (op & 0x0f); |
| 116 | else // reg offset |
| 117 | t = regs[op & 0x000f]; |
| 118 | |
| 119 | if (!BIT_SET(op, 23)) |
| 120 | t = -t; |
| 121 | addr = regs[rn] + t; |
| 122 | |
| 123 | if (BIT_SET(op, 20)) { // Load |
| 124 | ret = xread16(addr); |
| 125 | regs[rd] = ret; |
| 126 | } |
| 127 | else |
| 128 | xwrite16(addr, regs[rd]); |
| 129 | } |
| 130 | else if ((op & 0x0d200000) == 0x05000000) { // AM2: LDR[B], STR[B] |
| 131 | if (BIT_SET(op, 25)) { // reg offs |
| 132 | if (BIT_SET(op, 4)) |
| 133 | goto unhandled; |
| 134 | |
| 135 | t = regs[op & 0x000f]; |
| 136 | shift = (op & 0x0f80) >> 7; |
| 137 | switch ((op & 0x0060) >> 5) { |
| 138 | case 0: t = t << shift; break; |
| 139 | case 1: t = t >> (shift + 1); break; |
| 140 | case 2: t = (signed int)t >> (shift + 1); break; |
| 141 | case 3: goto unhandled; // I'm just lazy |
| 142 | } |
| 143 | } |
| 144 | else // imm offs |
| 145 | t = op & 0x0fff; |
| 146 | |
| 147 | if (!BIT_SET(op, 23)) |
| 148 | t = -t; |
| 149 | addr = regs[rn] + t; |
| 150 | |
| 151 | if (BIT_SET(op, 20)) { // Load |
| 152 | if (BIT_SET(op, 22)) // Byte |
| 153 | ret = xread8(addr); |
| 154 | else |
| 155 | ret = xread32(addr); |
| 156 | regs[rd] = ret; |
| 157 | } |
| 158 | else { |
| 159 | if (BIT_SET(op, 22)) // Byte |
| 160 | xwrite8(addr, regs[rd]); |
| 161 | else |
| 162 | xwrite32(addr, regs[rd]); |
| 163 | } |
| 164 | } |
| 165 | else |
| 166 | goto unhandled; |
| 167 | |
| 168 | if (addr != addr_check) { |
| 169 | fprintf(stderr, "bad calculated addr: %08x vs %08x\n", addr, addr_check); |
| 170 | abort(); |
| 171 | } |
| 172 | return; |
| 173 | |
| 174 | unhandled: |
| 175 | fprintf(stderr, "unhandled IO op %08x @ %08x\n", op, addr_pc); |
| 176 | } |
| 177 | |
| 178 | static void segv_sigaction(int num, siginfo_t *info, void *ctx) |
| 179 | { |
| 180 | struct ucontext *context = ctx; |
| 181 | u32 *regs = (u32 *)&context->uc_mcontext.arm_r0; |
| 182 | u32 op = *(u32 *)regs[15]; |
| 183 | |
| 184 | //printf("segv %d %p @ %08x\n", info->si_code, info->si_addr, regs[15]); |
| 185 | /* |
| 186 | static int thissec, sfps; |
| 187 | struct timeval tv; |
| 188 | gettimeofday(&tv, NULL); |
| 189 | sfps++; |
| 190 | if (tv.tv_sec != thissec) { |
| 191 | printf("%d\n", sfps); |
| 192 | sfps = 0; |
| 193 | thissec = tv.tv_sec; |
| 194 | } |
| 195 | */ |
| 196 | |
| 197 | handle_op(regs[15], op, regs, (u32)info->si_addr); |
| 198 | regs[15] += 4; |
| 199 | return; |
| 200 | |
| 201 | //signal(num, SIG_DFL); |
| 202 | //raise(num); |
| 203 | } |
| 204 | |
| 205 | #define LINKPAGE_SIZE 0x1000 |
| 206 | |
| 207 | struct linkpage { |
| 208 | u32 (*xread8)(u32 a); |
| 209 | u32 (*xread16)(u32 a); |
| 210 | u32 (*xread32)(u32 a); |
| 211 | void (*xwrite8)(u32 a, u32 d); |
| 212 | void (*xwrite16)(u32 a, u32 d); |
| 213 | void (*xwrite32)(u32 a, u32 d); |
| 214 | u32 retval; |
| 215 | u32 *reg_ptr; |
| 216 | u32 saved_regs[6]; // r0-r3,r12,lr |
| 217 | u32 code[0]; |
| 218 | }; |
| 219 | |
| 220 | static struct linkpage *g_linkpage; |
| 221 | static u32 *g_code_ptr; |
| 222 | |
| 223 | void emu_init(void *map_bottom) |
| 224 | { |
| 225 | struct sigaction segv_action = { |
| 226 | .sa_sigaction = segv_sigaction, |
| 227 | .sa_flags = SA_SIGINFO, |
| 228 | }; |
| 229 | struct linkpage init_linkpage = { |
| 230 | .xread8 = xread8, |
| 231 | .xread16 = xread16, |
| 232 | .xread32 = xread32, |
| 233 | .xwrite8 = xwrite8, |
| 234 | .xwrite16 = xwrite16, |
| 235 | .xwrite32 = xwrite32, |
| 236 | }; |
| 237 | void *ret; |
| 238 | |
| 239 | sigemptyset(&segv_action.sa_mask); |
| 240 | sigaction(SIGSEGV, &segv_action, NULL); |
| 241 | |
| 242 | g_linkpage = (void *)(((u32)map_bottom - LINKPAGE_SIZE) & ~0xfff); |
| 243 | ret = mmap(g_linkpage, LINKPAGE_SIZE, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); |
| 244 | if (ret != g_linkpage) { |
| 245 | perror("mmap linkpage"); |
| 246 | exit(1); |
| 247 | } |
| 248 | printf("linkpage @ %p\n", g_linkpage); |
| 249 | memcpy(g_linkpage, &init_linkpage, sizeof(*g_linkpage)); |
| 250 | g_linkpage->reg_ptr = g_linkpage->saved_regs; |
| 251 | g_code_ptr = g_linkpage->code; |
| 252 | |
| 253 | memdev = open("/dev/mem", O_RDWR); |
| 254 | memregs = mmap(NULL, 0x10000, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xc0000000); |
| 255 | blitter = mmap(NULL, 0x100, PROT_READ|PROT_WRITE, MAP_SHARED, memdev, 0xe0020000); |
| 256 | printf("mapped %d %p %p\n", memdev, memregs, blitter); |
| 257 | } |
| 258 | |
| 259 | void *emu_mmap_dev(unsigned int length, int prot, int flags, unsigned int offset) |
| 260 | { |
| 261 | char name[32]; |
| 262 | int fd; |
| 263 | |
| 264 | if ((offset & ~0xffff) == 0xc0000000) { |
| 265 | return mmap((void *)0x7f000000, length, PROT_NONE, |
| 266 | MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0); |
| 267 | } |
| 268 | if ((offset & ~0xffff) == 0xe0020000) { |
| 269 | return mmap((void *)0x7f100000, length, PROT_NONE, |
| 270 | MAP_PRIVATE|MAP_ANONYMOUS|MAP_FIXED|MAP_NORESERVE, -1, 0); |
| 271 | } |
| 272 | // pass through |
| 273 | if ((offset & 0xfe000000) == 0x02000000) |
| 274 | return mmap(NULL, length, prot, flags, memdev, offset); |
| 275 | |
| 276 | sprintf(name, "m%08x", offset); |
| 277 | fd = open(name, O_CREAT|O_RDWR, 0644); |
| 278 | lseek(fd, length - 1, SEEK_SET); |
| 279 | name[0] = 0; |
| 280 | write(fd, name, 1); |
| 281 | |
| 282 | return mmap(NULL, length, prot, MAP_SHARED, fd, 0); |
| 283 | } |
| 284 | |