1 /* $NetBSD: wsdisplay_glyphcache.c,v 1.6 2014/01/13 19:30:33 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 gc->gc_buckets = NULL; 71 gc->gc_numbuckets = 0; 72 if (lines < 0) lines = 0; 73 cache_lines = lines / cellheight; 74 gc->gc_numcells = cache_lines * gc->gc_cellsperline; 75 76 /* now allocate buckets */ 77 buckets = (gc->gc_numcells / 223); 78 if ((buckets * 223) < gc->gc_numcells) 79 buckets++; 80 81 /* 82 * if we don't have enough video memory to cache at least a few glyphs 83 * we stop right here 84 */ 85 if (buckets < 1) 86 return ENOMEM; 87 88 gc->gc_buckets = kmem_alloc(sizeof(gc_bucket) * buckets, KM_SLEEP); 89 if (gc->gc_buckets == NULL) { 90 aprint_error("%s: can't allocate memory\n", __func__); 91 return ENOMEM; 92 } 93 gc->gc_numbuckets = buckets; 94 95 DPRINTF("%s: using %d buckets\n", __func__, buckets); 96 for (i = 0; i < buckets; i++) { 97 b = &gc->gc_buckets[i]; 98 b->gb_firstcell = usedcells; 99 b->gb_numcells = min(223, gc->gc_numcells - usedcells); 100 usedcells += 223; 101 b->gb_usedcells = 0; 102 b->gb_index = -1; 103 } 104 105 /* initialize the attribute map... */ 106 for (i = 0; i < 256; i++) { 107 gc->gc_attrmap[i] = -1; 108 } 109 110 /* first bucket goes to default attr */ 111 idx = attr2idx(attr); 112 if (idx >= 0) { 113 gc->gc_attrmap[idx] = 0; 114 gc->gc_buckets[0].gb_index = idx; 115 } 116 117 glyphcache_wipe(gc); 118 DPRINTF("%s: using %d cells total, from %d width %d\n", __func__, 119 gc->gc_numcells, gc->gc_firstline, gc->gc_cellsperline); 120 return 0; 121 } 122 123 void 124 glyphcache_wipe(glyphcache *gc) 125 { 126 gc_bucket *b; 127 int i, j, idx; 128 129 if ((gc->gc_buckets == NULL) || (gc->gc_numbuckets < 1)) 130 return; 131 132 idx = gc->gc_buckets[0].gb_index; 133 134 /* empty all the buckets */ 135 for (i = 0; i < gc->gc_numbuckets; i++) { 136 b = &gc->gc_buckets[i]; 137 b->gb_usedcells = 0; 138 b->gb_index = -1; 139 for (j = 0; j < b->gb_numcells; j++) 140 b->gb_map[j] = -1; 141 } 142 143 for (i = 0; i < 256; i++) { 144 gc->gc_attrmap[i] = -1; 145 } 146 147 /* now put the first bucket back where it was */ 148 gc->gc_attrmap[idx] = 0; 149 gc->gc_buckets[0].gb_index = idx; 150 } 151 152 /* 153 * add a glyph drawn at (x,y) to the cache as (c) 154 * call this only if glyphcache_try() returned GC_ADD 155 * caller or gc_bitblt must make sure the glyph is actually completely drawn 156 */ 157 int 158 glyphcache_add(glyphcache *gc, int c, int x, int y) 159 { 160 gc_bucket *b = gc->gc_next; 161 int cell; 162 int cx, cy; 163 164 if (b->gb_usedcells >= b->gb_numcells) 165 return ENOMEM; 166 cell = atomic_add_int_nv(&b->gb_usedcells, 1) - 1; 167 cell += b->gb_firstcell; 168 cy = gc->gc_firstline + 169 (cell / gc->gc_cellsperline) * gc->gc_cellheight; 170 cx = (cell % gc->gc_cellsperline) * gc->gc_cellwidth; 171 b->gb_map[c - 33] = (cx << 16) | cy; 172 gc->gc_bitblt(gc->gc_blitcookie, x, y, cx, cy, 173 gc->gc_cellwidth, gc->gc_cellheight, gc->gc_rop); 174 if (gc->gc_underline & 1) { 175 glyphcache_underline(gc, x, y, gc->gc_underline); 176 } 177 return 0; 178 } 179 180 void 181 glyphcache_underline(glyphcache *gc, int x, int y, long attr) 182 { 183 if (gc->gc_rectfill == NULL) 184 return; 185 186 gc->gc_rectfill(gc->gc_blitcookie, x, y + gc->gc_cellheight - 2, 187 gc->gc_cellwidth, 1, attr); 188 } 189 /* 190 * check if (c) is in the cache, if so draw it at (x,y) 191 * return: 192 * - GC_OK when the glyph was found 193 * - GC_ADD when the glyph wasn't found but can be added 194 * - GC_NOPE when the glyph can't be cached 195 */ 196 int 197 glyphcache_try(glyphcache *gc, int c, int x, int y, long attr) 198 { 199 int cell, cx, cy, idx, bi; 200 gc_bucket *b; 201 202 idx = attr2idx(attr); 203 /* see if we're in range */ 204 if ((c < 33) || (c > 255) || (idx < 0)) 205 return GC_NOPE; 206 /* see if there's already a bucket for this attribute */ 207 bi = gc->gc_attrmap[idx]; 208 if (bi == -1) { 209 /* nope, see if there's an empty one left */ 210 bi = 1; 211 while ((bi < gc->gc_numbuckets) && 212 (gc->gc_buckets[bi].gb_index != -1)) { 213 bi++; 214 } 215 if (bi < gc->gc_numbuckets) { 216 /* found one -> grab it */ 217 gc->gc_attrmap[idx] = bi; 218 b = &gc->gc_buckets[bi]; 219 b->gb_index = idx; 220 b->gb_usedcells = 0; 221 /* make sure this doesn't get evicted right away */ 222 b->gb_lastread = time_uptime; 223 } else { 224 /* 225 * still nothing 226 * steal the least recently read bucket 227 */ 228 time_t moo = time_uptime; 229 int i, oldest = 1; 230 231 for (i = 1; i < gc->gc_numbuckets; i++) { 232 if (gc->gc_buckets[i].gb_lastread < moo) { 233 oldest = i; 234 moo = gc->gc_buckets[i].gb_lastread; 235 } 236 } 237 238 /* if we end up here all buckets must be in use */ 239 b = &gc->gc_buckets[oldest]; 240 gc->gc_attrmap[b->gb_index] = -1; 241 b->gb_index = idx; 242 b->gb_usedcells = 0; 243 gc->gc_attrmap[idx] = oldest; 244 /* now scrub it */ 245 for (i = 0; i < b->gb_numcells; i++) 246 b->gb_map[i] = -1; 247 /* and set the time stamp */ 248 b->gb_lastread = time_uptime; 249 } 250 } else { 251 /* found one */ 252 b = &gc->gc_buckets[bi]; 253 } 254 255 /* see if there's room in the bucket */ 256 if (b->gb_usedcells >= b->gb_numcells) 257 return GC_NOPE; 258 259 cell = b->gb_map[c - 33]; 260 if (cell == -1) { 261 gc->gc_next = b; 262 gc->gc_underline = attr; 263 return GC_ADD; 264 } 265 266 /* it's in the cache - draw it */ 267 cy = cell & 0xffff; 268 cx = (cell >> 16) & 0xffff; 269 gc->gc_bitblt(gc->gc_blitcookie, cx, cy, x, y, 270 gc->gc_cellwidth, gc->gc_cellheight, gc->gc_rop); 271 /* and underline it if needed */ 272 if (attr & 1) 273 glyphcache_underline(gc, x, y, attr); 274 /* update bucket's time stamp */ 275 b->gb_lastread = time_uptime; 276 return GC_OK; 277 } 278