atafb_utils.h (11274B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _VIDEO_ATAFB_UTILS_H 3#define _VIDEO_ATAFB_UTILS_H 4 5/* ================================================================= */ 6/* Utility Assembler Functions */ 7/* ================================================================= */ 8 9/* ====================================================================== */ 10 11/* Those of a delicate disposition might like to skip the next couple of 12 * pages. 13 * 14 * These functions are drop in replacements for memmove and 15 * memset(_, 0, _). However their five instances add at least a kilobyte 16 * to the object file. You have been warned. 17 * 18 * Not a great fan of assembler for the sake of it, but I think 19 * that these routines are at least 10 times faster than their C 20 * equivalents for large blits, and that's important to the lowest level of 21 * a graphics driver. Question is whether some scheme with the blitter 22 * would be faster. I suspect not for simple text system - not much 23 * asynchrony. 24 * 25 * Code is very simple, just gruesome expansion. Basic strategy is to 26 * increase data moved/cleared at each step to 16 bytes to reduce 27 * instruction per data move overhead. movem might be faster still 28 * For more than 15 bytes, we try to align the write direction on a 29 * longword boundary to get maximum speed. This is even more gruesome. 30 * Unaligned read/write used requires 68020+ - think this is a problem? 31 * 32 * Sorry! 33 */ 34 35 36/* ++roman: I've optimized Robert's original versions in some minor 37 * aspects, e.g. moveq instead of movel, let gcc choose the registers, 38 * use movem in some places... 39 * For other modes than 1 plane, lots of more such assembler functions 40 * were needed (e.g. the ones using movep or expanding color values). 41 */ 42 43/* ++andreas: more optimizations: 44 subl #65536,d0 replaced by clrw d0; subql #1,d0 for dbcc 45 addal is faster than addaw 46 movep is rather expensive compared to ordinary move's 47 some functions rewritten in C for clarity, no speed loss */ 48 49static inline void *fb_memclear_small(void *s, size_t count) 50{ 51 if (!count) 52 return 0; 53 54 asm volatile ("\n" 55 " lsr.l #1,%1 ; jcc 1f ; move.b %2,-(%0)\n" 56 "1: lsr.l #1,%1 ; jcc 1f ; move.w %2,-(%0)\n" 57 "1: lsr.l #1,%1 ; jcc 1f ; move.l %2,-(%0)\n" 58 "1: lsr.l #1,%1 ; jcc 1f ; move.l %2,-(%0) ; move.l %2,-(%0)\n" 59 "1:" 60 : "=a" (s), "=d" (count) 61 : "d" (0), "0" ((char *)s + count), "1" (count)); 62 asm volatile ("\n" 63 " subq.l #1,%1\n" 64 " jcs 3f\n" 65 " move.l %2,%%d4; move.l %2,%%d5; move.l %2,%%d6\n" 66 "2: movem.l %2/%%d4/%%d5/%%d6,-(%0)\n" 67 " dbra %1,2b\n" 68 "3:" 69 : "=a" (s), "=d" (count) 70 : "d" (0), "0" (s), "1" (count) 71 : "d4", "d5", "d6" 72 ); 73 74 return 0; 75} 76 77 78static inline void *fb_memclear(void *s, size_t count) 79{ 80 if (!count) 81 return 0; 82 83 if (count < 16) { 84 asm volatile ("\n" 85 " lsr.l #1,%1 ; jcc 1f ; clr.b (%0)+\n" 86 "1: lsr.l #1,%1 ; jcc 1f ; clr.w (%0)+\n" 87 "1: lsr.l #1,%1 ; jcc 1f ; clr.l (%0)+\n" 88 "1: lsr.l #1,%1 ; jcc 1f ; clr.l (%0)+ ; clr.l (%0)+\n" 89 "1:" 90 : "=a" (s), "=d" (count) 91 : "0" (s), "1" (count)); 92 } else { 93 long tmp; 94 asm volatile ("\n" 95 " move.l %1,%2\n" 96 " lsr.l #1,%2 ; jcc 1f ; clr.b (%0)+ ; subq.w #1,%1\n" 97 " lsr.l #1,%2 ; jcs 2f\n" /* %0 increased=>bit 2 switched*/ 98 " clr.w (%0)+ ; subq.w #2,%1 ; jra 2f\n" 99 "1: lsr.l #1,%2 ; jcc 2f\n" 100 " clr.w (%0)+ ; subq.w #2,%1\n" 101 "2: move.w %1,%2; lsr.l #2,%1 ; jeq 6f\n" 102 " lsr.l #1,%1 ; jcc 3f ; clr.l (%0)+\n" 103 "3: lsr.l #1,%1 ; jcc 4f ; clr.l (%0)+ ; clr.l (%0)+\n" 104 "4: subq.l #1,%1 ; jcs 6f\n" 105 "5: clr.l (%0)+; clr.l (%0)+ ; clr.l (%0)+ ; clr.l (%0)+\n" 106 " dbra %1,5b ; clr.w %1; subq.l #1,%1; jcc 5b\n" 107 "6: move.w %2,%1; btst #1,%1 ; jeq 7f ; clr.w (%0)+\n" 108 "7: btst #0,%1 ; jeq 8f ; clr.b (%0)+\n" 109 "8:" 110 : "=a" (s), "=d" (count), "=d" (tmp) 111 : "0" (s), "1" (count)); 112 } 113 114 return 0; 115} 116 117 118static inline void *fb_memset255(void *s, size_t count) 119{ 120 if (!count) 121 return 0; 122 123 asm volatile ("\n" 124 " lsr.l #1,%1 ; jcc 1f ; move.b %2,-(%0)\n" 125 "1: lsr.l #1,%1 ; jcc 1f ; move.w %2,-(%0)\n" 126 "1: lsr.l #1,%1 ; jcc 1f ; move.l %2,-(%0)\n" 127 "1: lsr.l #1,%1 ; jcc 1f ; move.l %2,-(%0) ; move.l %2,-(%0)\n" 128 "1:" 129 : "=a" (s), "=d" (count) 130 : "d" (-1), "0" ((char *)s+count), "1" (count)); 131 asm volatile ("\n" 132 " subq.l #1,%1 ; jcs 3f\n" 133 " move.l %2,%%d4; move.l %2,%%d5; move.l %2,%%d6\n" 134 "2: movem.l %2/%%d4/%%d5/%%d6,-(%0)\n" 135 " dbra %1,2b\n" 136 "3:" 137 : "=a" (s), "=d" (count) 138 : "d" (-1), "0" (s), "1" (count) 139 : "d4", "d5", "d6"); 140 141 return 0; 142} 143 144 145static inline void *fb_memmove(void *d, const void *s, size_t count) 146{ 147 if (d < s) { 148 if (count < 16) { 149 asm volatile ("\n" 150 " lsr.l #1,%2 ; jcc 1f ; move.b (%1)+,(%0)+\n" 151 "1: lsr.l #1,%2 ; jcc 1f ; move.w (%1)+,(%0)+\n" 152 "1: lsr.l #1,%2 ; jcc 1f ; move.l (%1)+,(%0)+\n" 153 "1: lsr.l #1,%2 ; jcc 1f ; move.l (%1)+,(%0)+ ; move.l (%1)+,(%0)+\n" 154 "1:" 155 : "=a" (d), "=a" (s), "=d" (count) 156 : "0" (d), "1" (s), "2" (count)); 157 } else { 158 long tmp; 159 asm volatile ("\n" 160 " move.l %0,%3\n" 161 " lsr.l #1,%3 ; jcc 1f ; move.b (%1)+,(%0)+ ; subqw #1,%2\n" 162 " lsr.l #1,%3 ; jcs 2f\n" /* %0 increased=>bit 2 switched*/ 163 " move.w (%1)+,(%0)+ ; subqw #2,%2 ; jra 2f\n" 164 "1: lsr.l #1,%3 ; jcc 2f\n" 165 " move.w (%1)+,(%0)+ ; subqw #2,%2\n" 166 "2: move.w %2,%-; lsr.l #2,%2 ; jeq 6f\n" 167 " lsr.l #1,%2 ; jcc 3f ; move.l (%1)+,(%0)+\n" 168 "3: lsr.l #1,%2 ; jcc 4f ; move.l (%1)+,(%0)+ ; move.l (%1)+,(%0)+\n" 169 "4: subq.l #1,%2 ; jcs 6f\n" 170 "5: move.l (%1)+,(%0)+; move.l (%1)+,(%0)+\n" 171 " move.l (%1)+,(%0)+; move.l (%1)+,(%0)+\n" 172 " dbra %2,5b ; clr.w %2; subq.l #1,%2; jcc 5b\n" 173 "6: move.w %+,%2; btst #1,%2 ; jeq 7f ; move.w (%1)+,(%0)+\n" 174 "7: btst #0,%2 ; jeq 8f ; move.b (%1)+,(%0)+\n" 175 "8:" 176 : "=a" (d), "=a" (s), "=d" (count), "=d" (tmp) 177 : "0" (d), "1" (s), "2" (count)); 178 } 179 } else { 180 if (count < 16) { 181 asm volatile ("\n" 182 " lsr.l #1,%2 ; jcc 1f ; move.b -(%1),-(%0)\n" 183 "1: lsr.l #1,%2 ; jcc 1f ; move.w -(%1),-(%0)\n" 184 "1: lsr.l #1,%2 ; jcc 1f ; move.l -(%1),-(%0)\n" 185 "1: lsr.l #1,%2 ; jcc 1f ; move.l -(%1),-(%0) ; move.l -(%1),-(%0)\n" 186 "1:" 187 : "=a" (d), "=a" (s), "=d" (count) 188 : "0" ((char *) d + count), "1" ((char *) s + count), "2" (count)); 189 } else { 190 long tmp; 191 192 asm volatile ("\n" 193 " move.l %0,%3\n" 194 " lsr.l #1,%3 ; jcc 1f ; move.b -(%1),-(%0) ; subqw #1,%2\n" 195 " lsr.l #1,%3 ; jcs 2f\n" /* %0 increased=>bit 2 switched*/ 196 " move.w -(%1),-(%0) ; subqw #2,%2 ; jra 2f\n" 197 "1: lsr.l #1,%3 ; jcc 2f\n" 198 " move.w -(%1),-(%0) ; subqw #2,%2\n" 199 "2: move.w %2,%-; lsr.l #2,%2 ; jeq 6f\n" 200 " lsr.l #1,%2 ; jcc 3f ; move.l -(%1),-(%0)\n" 201 "3: lsr.l #1,%2 ; jcc 4f ; move.l -(%1),-(%0) ; move.l -(%1),-(%0)\n" 202 "4: subq.l #1,%2 ; jcs 6f\n" 203 "5: move.l -(%1),-(%0); move.l -(%1),-(%0)\n" 204 " move.l -(%1),-(%0); move.l -(%1),-(%0)\n" 205 " dbra %2,5b ; clr.w %2; subq.l #1,%2; jcc 5b\n" 206 "6: move.w %+,%2; btst #1,%2 ; jeq 7f ; move.w -(%1),-(%0)\n" 207 "7: btst #0,%2 ; jeq 8f ; move.b -(%1),-(%0)\n" 208 "8:" 209 : "=a" (d), "=a" (s), "=d" (count), "=d" (tmp) 210 : "0" ((char *) d + count), "1" ((char *) s + count), "2" (count)); 211 } 212 } 213 214 return 0; 215} 216 217 218/* ++andreas: Simple and fast version of memmove, assumes size is 219 divisible by 16, suitable for moving the whole screen bitplane */ 220static inline void fast_memmove(char *dst, const char *src, size_t size) 221{ 222 if (!size) 223 return; 224 if (dst < src) 225 asm volatile ("\n" 226 "1: movem.l (%0)+,%%d0/%%d1/%%a0/%%a1\n" 227 " movem.l %%d0/%%d1/%%a0/%%a1,%1@\n" 228 " addq.l #8,%1; addq.l #8,%1\n" 229 " dbra %2,1b\n" 230 " clr.w %2; subq.l #1,%2\n" 231 " jcc 1b" 232 : "=a" (src), "=a" (dst), "=d" (size) 233 : "0" (src), "1" (dst), "2" (size / 16 - 1) 234 : "d0", "d1", "a0", "a1", "memory"); 235 else 236 asm volatile ("\n" 237 "1: subq.l #8,%0; subq.l #8,%0\n" 238 " movem.l %0@,%%d0/%%d1/%%a0/%%a1\n" 239 " movem.l %%d0/%%d1/%%a0/%%a1,-(%1)\n" 240 " dbra %2,1b\n" 241 " clr.w %2; subq.l #1,%2\n" 242 " jcc 1b" 243 : "=a" (src), "=a" (dst), "=d" (size) 244 : "0" (src + size), "1" (dst + size), "2" (size / 16 - 1) 245 : "d0", "d1", "a0", "a1", "memory"); 246} 247 248#ifdef BPL 249 250/* 251 * This expands a up to 8 bit color into two longs 252 * for movel operations. 253 */ 254static const u32 four2long[] = { 255 0x00000000, 0x000000ff, 0x0000ff00, 0x0000ffff, 256 0x00ff0000, 0x00ff00ff, 0x00ffff00, 0x00ffffff, 257 0xff000000, 0xff0000ff, 0xff00ff00, 0xff00ffff, 258 0xffff0000, 0xffff00ff, 0xffffff00, 0xffffffff, 259}; 260 261static inline void expand8_col2mask(u8 c, u32 m[]) 262{ 263 m[0] = four2long[c & 15]; 264#if BPL > 4 265 m[1] = four2long[c >> 4]; 266#endif 267} 268 269static inline void expand8_2col2mask(u8 fg, u8 bg, u32 fgm[], u32 bgm[]) 270{ 271 fgm[0] = four2long[fg & 15] ^ (bgm[0] = four2long[bg & 15]); 272#if BPL > 4 273 fgm[1] = four2long[fg >> 4] ^ (bgm[1] = four2long[bg >> 4]); 274#endif 275} 276 277/* 278 * set an 8bit value to a color 279 */ 280static inline void fill8_col(u8 *dst, u32 m[]) 281{ 282 u32 tmp = m[0]; 283 dst[0] = tmp; 284 dst[2] = (tmp >>= 8); 285#if BPL > 2 286 dst[4] = (tmp >>= 8); 287 dst[6] = tmp >> 8; 288#endif 289#if BPL > 4 290 tmp = m[1]; 291 dst[8] = tmp; 292 dst[10] = (tmp >>= 8); 293 dst[12] = (tmp >>= 8); 294 dst[14] = tmp >> 8; 295#endif 296} 297 298/* 299 * set an 8bit value according to foreground/background color 300 */ 301static inline void fill8_2col(u8 *dst, u8 fg, u8 bg, u32 mask) 302{ 303 u32 fgm[2], bgm[2], tmp; 304 305 expand8_2col2mask(fg, bg, fgm, bgm); 306 307 mask |= mask << 8; 308#if BPL > 2 309 mask |= mask << 16; 310#endif 311 tmp = (mask & fgm[0]) ^ bgm[0]; 312 dst[0] = tmp; 313 dst[2] = (tmp >>= 8); 314#if BPL > 2 315 dst[4] = (tmp >>= 8); 316 dst[6] = tmp >> 8; 317#endif 318#if BPL > 4 319 tmp = (mask & fgm[1]) ^ bgm[1]; 320 dst[8] = tmp; 321 dst[10] = (tmp >>= 8); 322 dst[12] = (tmp >>= 8); 323 dst[14] = tmp >> 8; 324#endif 325} 326 327static const u32 two2word[] = { 328 0x00000000, 0xffff0000, 0x0000ffff, 0xffffffff 329}; 330 331static inline void expand16_col2mask(u8 c, u32 m[]) 332{ 333 m[0] = two2word[c & 3]; 334#if BPL > 2 335 m[1] = two2word[(c >> 2) & 3]; 336#endif 337#if BPL > 4 338 m[2] = two2word[(c >> 4) & 3]; 339 m[3] = two2word[c >> 6]; 340#endif 341} 342 343static inline void expand16_2col2mask(u8 fg, u8 bg, u32 fgm[], u32 bgm[]) 344{ 345 bgm[0] = two2word[bg & 3]; 346 fgm[0] = two2word[fg & 3] ^ bgm[0]; 347#if BPL > 2 348 bgm[1] = two2word[(bg >> 2) & 3]; 349 fgm[1] = two2word[(fg >> 2) & 3] ^ bgm[1]; 350#endif 351#if BPL > 4 352 bgm[2] = two2word[(bg >> 4) & 3]; 353 fgm[2] = two2word[(fg >> 4) & 3] ^ bgm[2]; 354 bgm[3] = two2word[bg >> 6]; 355 fgm[3] = two2word[fg >> 6] ^ bgm[3]; 356#endif 357} 358 359static inline u32 *fill16_col(u32 *dst, int rows, u32 m[]) 360{ 361 while (rows) { 362 *dst++ = m[0]; 363#if BPL > 2 364 *dst++ = m[1]; 365#endif 366#if BPL > 4 367 *dst++ = m[2]; 368 *dst++ = m[3]; 369#endif 370 rows--; 371 } 372 return dst; 373} 374 375static inline void memmove32_col(void *dst, void *src, u32 mask, u32 h, u32 bytes) 376{ 377 u32 *s, *d, v; 378 379 s = src; 380 d = dst; 381 do { 382 v = (*s++ & mask) | (*d & ~mask); 383 *d++ = v; 384#if BPL > 2 385 v = (*s++ & mask) | (*d & ~mask); 386 *d++ = v; 387#endif 388#if BPL > 4 389 v = (*s++ & mask) | (*d & ~mask); 390 *d++ = v; 391 v = (*s++ & mask) | (*d & ~mask); 392 *d++ = v; 393#endif 394 d = (u32 *)((u8 *)d + bytes); 395 s = (u32 *)((u8 *)s + bytes); 396 } while (--h); 397} 398 399#endif 400 401#endif /* _VIDEO_ATAFB_UTILS_H */