1 /* $NetBSD: wsdisplay_glyphcache.c,v 1.5 2012/11/13 20:29:03 macallan Exp $ */ 2 3 /* 4 * Copyright (c) 2012 Michael Lorenz 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 /* 29 * a simple glyph cache in offscreen memory 30 * For now it only caches glyphs with the default attribute ( assuming they're 31 * the most commonly used glyphs ) but the API should at least not prevent 32 * more sophisticated caching algorithms 33 */ 34 35 #include <sys/systm.h> 36 #include <sys/atomic.h> 37 #include <sys/errno.h> 38 #include <sys/kmem.h> 39 #include <dev/wscons/wsdisplay_glyphcachevar.h> 40 #include "opt_glyphcache.h" 41 42 #ifdef GLYPHCACHE_DEBUG 43 #define DPRINTF aprint_normal 44 #else 45 #define DPRINTF while (0) printf 46 #endif 47 48 static inline int 49 attr2idx(long attr) 50 { 51 if ((attr & 0xf0f0fff8) != 0) 52 return -1; 53 54 return (((attr >> 16) & 0x0f) | ((attr >> 20) & 0xf0)); 55 } 56 57 /* first line, lines, width, attr */ 58 int 59 glyphcache_init(glyphcache *gc, int first, int lines, int width, 60 int cellwidth, int cellheight, long attr) 61 { 62 int cache_lines, buckets, i, usedcells = 0, idx; 63 gc_bucket *b; 64 65 /* first the geometry stuff */ 66 gc->gc_cellwidth = cellwidth; 67 gc->gc_cellheight = cellheight; 68 gc->gc_firstline = first; 69 gc->gc_cellsperline = width / cellwidth; 70 if (lines < 0) lines = 0; 71 cache_lines = lines / cellheight; 72 gc->gc_numcells = cache_lines * gc->gc_cellsperline; 73 74 /* now allocate buckets */ 75 buckets = (gc->gc_numcells / 223); 76 if ((buckets * 223) < gc->gc_numcells) 77 buckets++; 78 79 /* 80 * if we don't have enough video memory to cache at least a few glyphs 81 * we stop right here 82 */ 83 if (buckets < 1) 84 return ENOMEM; 85 86 gc->gc_buckets = kmem_alloc(sizeof(gc_bucket) * buckets, KM_SLEEP); 87 if (gc->gc_buckets == NULL) { 88 aprint_error("%s: can't allocate memory\n", __func__); 89 return ENOMEM; 90 } 91 gc->gc_numbuckets = buckets; 92 93 DPRINTF("%s: using %d buckets\n", __func__, buckets); 94 for (i = 0; i < buckets; i++) { 95 b = &gc->gc_buckets[i]; 96 b->gb_firstcell = usedcells; 97 b->gb_numcells = min(223, gc->gc_numcells - usedcells); 98 usedcells += 223; 99 b->gb_usedcells = 0; 100 b->gb_index = -1; 101 } 102 103 /* initialize the attribute map... */ 104 for (i = 0; i < 256; i++) { 105 gc->gc_attrmap[i] = -1; 106 } 107 108 /* first bucket goes to default attr */ 109 idx = attr2idx(attr); 110 if (idx >= 0) { 111 gc->gc_attrmap[idx] = 0; 112 gc->gc_buckets[0].gb_index = idx; 113 } 114 115 glyphcache_wipe(gc); 116 DPRINTF("%s: using %d cells total, from %d width %d\n", __func__, 117 gc->gc_numcells, gc->gc_firstline, gc->gc_cellsperline); 118 return 0; 119 } 120 121 void 122 glyphcache_wipe(glyphcache *gc) 123 { 124 gc_bucket *b; 125 int i, j, idx; 126 127 idx = gc->gc_buckets[0].gb_index; 128 129 /* empty all the buckets */ 130 for (i = 0; i < gc->gc_numbuckets; i++) { 131 b = &gc->gc_buckets[i]; 132 b->gb_usedcells = 0; 133 b->gb_index = -1; 134 for (j = 0; j < b->gb_numcells; j++) 135 b->gb_map[j] = -1; 136 } 137 138 for (i = 0; i < 256; i++) { 139 gc->gc_attrmap[i] = -1; 140 } 141 142 /* now put the first bucket back where it was */ 143 gc->gc_attrmap[idx] = 0; 144 gc->gc_buckets[0].gb_index = idx; 145 } 146 147 /* 148 * add a glyph drawn at (x,y) to the cache as (c) 149 * call this only if glyphcache_try() returned GC_ADD 150 * caller or gc_bitblt must make sure the glyph is actually completely drawn 151 */ 152 int 153 glyphcache_add(glyphcache *gc, int c, int x, int y) 154 { 155 gc_bucket *b = gc->gc_next; 156 int cell; 157 int cx, cy; 158 159 if (b->gb_usedcells >= b->gb_numcells) 160 return ENOMEM; 161 cell = atomic_add_int_nv(&b->gb_usedcells, 1) - 1; 162 cell += b->gb_firstcell; 163 cy = gc->gc_firstline + 164 (cell / gc->gc_cellsperline) * gc->gc_cellheight; 165 cx = (cell % gc->gc_cellsperline) * gc->gc_cellwidth; 166 b->gb_map[c - 33] = (cx << 16) | cy; 167 gc->gc_bitblt(gc->gc_blitcookie, x, y, cx, cy, 168 gc->gc_cellwidth, gc->gc_cellheight, gc->gc_rop); 169 if (gc->gc_underline & 1) { 170 glyphcache_underline(gc, x, y, gc->gc_underline); 171 } 172 return 0; 173 } 174 175 void 176 glyphcache_underline(glyphcache *gc, int x, int y, long attr) 177 { 178 if (gc->gc_rectfill == NULL) 179 return; 180 181 gc->gc_rectfill(gc->gc_blitcookie, x, y + gc->gc_cellheight - 2, 182 gc->gc_cellwidth, 1, attr); 183 } 184 /* 185 * check if (c) is in the cache, if so draw it at (x,y) 186 * return: 187 * - GC_OK when the glyph was found 188 * - GC_ADD when the glyph wasn't found but can be added 189 * - GC_NOPE when the glyph can't be cached 190 */ 191 int 192 glyphcache_try(glyphcache *gc, int c, int x, int y, long attr) 193 { 194 int cell, cx, cy, idx, bi; 195 gc_bucket *b; 196 197 idx = attr2idx(attr); 198 /* see if we're in range */ 199 if ((c < 33) || (c > 255) || (idx < 0)) 200 return GC_NOPE; 201 /* see if there's already a bucket for this attribute */ 202 bi = gc->gc_attrmap[idx]; 203 if (bi == -1) { 204 /* nope, see if there's an empty one left */ 205 bi = 1; 206 while ((bi < gc->gc_numbuckets) && 207 (gc->gc_buckets[bi].gb_index != -1)) { 208 bi++; 209 } 210 if (bi < gc->gc_numbuckets) { 211 /* found one -> grab it */ 212 gc->gc_attrmap[idx] = bi; 213 b = &gc->gc_buckets[bi]; 214 b->gb_index = idx; 215 b->gb_usedcells = 0; 216 /* make sure this doesn't get evicted right away */ 217 b->gb_lastread = time_uptime; 218 } else { 219 /* 220 * still nothing 221 * steal the least recently read bucket 222 */ 223 time_t moo = time_uptime; 224 int i, oldest = 1; 225 226 for (i = 1; i < gc->gc_numbuckets; i++) { 227 if (gc->gc_buckets[i].gb_lastread < moo) { 228 oldest = i; 229 moo = gc->gc_buckets[i].gb_lastread; 230 } 231 } 232 233 /* if we end up here all buckets must be in use */ 234 b = &gc->gc_buckets[oldest]; 235 gc->gc_attrmap[b->gb_index] = -1; 236 b->gb_index = idx; 237 b->gb_usedcells = 0; 238 gc->gc_attrmap[idx] = oldest; 239 /* now scrub it */ 240 for (i = 0; i < b->gb_numcells; i++) 241 b->gb_map[i] = -1; 242 /* and set the time stamp */ 243 b->gb_lastread = time_uptime; 244 } 245 } else { 246 /* found one */ 247 b = &gc->gc_buckets[bi]; 248 } 249 250 /* see if there's room in the bucket */ 251 if (b->gb_usedcells >= b->gb_numcells) 252 return GC_NOPE; 253 254 cell = b->gb_map[c - 33]; 255 if (cell == -1) { 256 gc->gc_next = b; 257 gc->gc_underline = attr; 258 return GC_ADD; 259 } 260 261 /* it's in the cache - draw it */ 262 cy = cell & 0xffff; 263 cx = (cell >> 16) & 0xffff; 264 gc->gc_bitblt(gc->gc_blitcookie, cx, cy, x, y, 265 gc->gc_cellwidth, gc->gc_cellheight, gc->gc_rop); 266 /* and underline it if needed */ 267 if (attr & 1) 268 glyphcache_underline(gc, x, y, attr); 269 /* update bucket's time stamp */ 270 b->gb_lastread = time_uptime; 271 return GC_OK; 272 } 273