drivers/video/cfbimgblt.c

   1 /*
   2  *  Generic BitBLT function for frame buffer with packed pixels of any depth.
   3  *
   4  *      Copyright (C)  June 1999 James Simmons
   5  *
   6  *  This file is subject to the terms and conditions of the GNU General Public
   7  *  License.  See the file COPYING in the main directory of this archive for
   8  *  more details.
   9  *
  10  * NOTES:
  11  *
  12  *    This function copys a image from system memory to video memory. The
  13  *  image can be a bitmap where each 0 represents the background color and
  14  *  each 1 represents the foreground color. Great for font handling. It can
  15  *  also be a color image. This is determined by image_depth. The color image
  16  *  must be laid out exactly in the same format as the framebuffer. Yes I know
  17  *  their are cards with hardware that coverts images of various depths to the
  18  *  framebuffer depth. But not every card has this. All images must be rounded
  19  *  up to the nearest byte. For example a bitmap 12 bits wide must be two
  20  *  bytes width.
  21  *
  22  *  Tony:
  23  *  Incorporate mask tables similar to fbcon-cfb*.c in 2.4 API.  This speeds
  24  *  up the code significantly.
  25  *
  26  *  Code for depths not multiples of BITS_PER_LONG is still kludgy, which is
  27  *  still processed a bit at a time.
  28  *
  29  *  Also need to add code to deal with cards endians that are different than
  30  *  the native cpu endians. I also need to deal with MSB position in the word.
  31  */
  32 #include <linux/config.h>
  33 #include <linux/module.h>
  34 #include <linux/string.h>
  35 #include <linux/fb.h>
  36 #include <asm/types.h>
  37
  38 #define DEBUG
  39
  40 #ifdef DEBUG
  41 #define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt,__FUNCTION__,## args)
  42 #else
  43 #define DPRINTK(fmt, args...)
  44 #endif
  45
  46 static u32 cfb_tab8[] = {
  47 #if defined(__BIG_ENDIAN)
  48     0x00000000,0x000000ff,0x0000ff00,0x0000ffff,
  49     0x00ff0000,0x00ff00ff,0x00ffff00,0x00ffffff,
  50     0xff000000,0xff0000ff,0xff00ff00,0xff00ffff,
  51     0xffff0000,0xffff00ff,0xffffff00,0xffffffff
  52 #elif defined(__LITTLE_ENDIAN)
  53     0x00000000,0xff000000,0x00ff0000,0xffff0000,
  54     0x0000ff00,0xff00ff00,0x00ffff00,0xffffff00,
  55     0x000000ff,0xff0000ff,0x00ff00ff,0xffff00ff,
  56     0x0000ffff,0xff00ffff,0x00ffffff,0xffffffff
  57 #else
  58 #error FIXME: No endianness??
  59 #endif
  60 };
  61
  62 static u32 cfb_tab16[] = {
  63 #if defined(__BIG_ENDIAN)
  64     0x00000000, 0x0000ffff, 0xffff0000, 0xffffffff
  65 #elif defined(__LITTLE_ENDIAN)
  66     0x00000000, 0xffff0000, 0x0000ffff, 0xffffffff
  67 #else
  68 #error FIXME: No endianness??
  69 #endif
  70 };
  71
  72 static u32 cfb_tab32[] = {
  73         0x00000000, 0xffffffff
  74 };
  75
  76 #define FB_WRITEL fb_writel
  77 #define FB_READL  fb_readl
  78
  79 #if defined (__BIG_ENDIAN)
  80 #define LEFT_POS(bpp)          (32 - bpp)
  81 #define SHIFT_HIGH(val, bits)  ((val) >> (bits))
  82 #define SHIFT_LOW(val, bits)   ((val) << (bits))
  83 #else
  84 #define LEFT_POS(bpp)          (0)
  85 #define SHIFT_HIGH(val, bits)  ((val) << (bits))
  86 #define SHIFT_LOW(val, bits)   ((val) >> (bits))
  87 #endif
  88
  89 static inline void color_imageblit(const struct fb_image *image,
  90                                    struct fb_info *p, u8 __iomem *dst1,
  91                                    u32 start_index,
  92                                    u32 pitch_index)
  93 {
  94         /* Draw the penguin */
  95         u32 __iomem *dst, *dst2;
  96         u32 color = 0, val, shift;
  97         int i, n, bpp = p->var.bits_per_pixel;
  98         u32 null_bits = 32 - bpp;
  99         u32 *palette = (u32 *) p->pseudo_palette;
 100         const u8 *src = image->data;
 101
 102         dst2 = (u32 __iomem *) dst1;
 103         for (i = image->height; i--; ) {
 104                 n = image->width;
 105                 dst = (u32 __iomem *) dst1;
 106                 shift = 0;
 107                 val = 0;
 108
 109                 if (start_index) {
 110                         u32 start_mask = ~(SHIFT_HIGH(~(u32)0, start_index));
 111                         val = FB_READL(dst) & start_mask;
 112                         shift = start_index;
 113                 }
 114                 while (n--) {
 115                         if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
 116                             p->fix.visual == FB_VISUAL_DIRECTCOLOR )
 117                                 color = palette[*src];
 118                         else
 119                                 color = *src;
 120                         color <<= LEFT_POS(bpp);
 121                         val |= SHIFT_HIGH(color, shift);
 122                         if (shift >= null_bits) {
 123                                 FB_WRITEL(val, dst++);
 124
 125                                 val = (shift == null_bits) ? 0 :
 126                                         SHIFT_LOW(color, 32 - shift);
 127                         }
 128                         shift += bpp;
 129                         shift &= (32 - 1);
 130                         src++;
 131                 }
 132                 if (shift) {
 133                         u32 end_mask = SHIFT_HIGH(~(u32)0, shift);
 134
 135                         FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
 136                 }
 137                 dst1 += p->fix.line_length;
 138                 if (pitch_index) {
 139                         dst2 += p->fix.line_length;
 140                         dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
 141
 142                         start_index += pitch_index;
 143                         start_index &= 32 - 1;
 144                 }
 145         }
 146 }
 147
 148 static inline void slow_imageblit(const struct fb_image *image, struct fb_info *p,
 149                                   u8 __iomem *dst1, u32 fgcolor,
 150                                   u32 bgcolor,
 151                                   u32 start_index,
 152                                   u32 pitch_index)
 153 {
 154         u32 shift, color = 0, bpp = p->var.bits_per_pixel;
 155         u32 __iomem *dst, *dst2;
 156         u32 val, pitch = p->fix.line_length;
 157         u32 null_bits = 32 - bpp;
 158         u32 spitch = (image->width+7)/8;
 159         const u8 *src = image->data, *s;
 160         u32 i, j, l;
 161
 162         dst2 = (u32 __iomem *) dst1;
 163
 164         for (i = image->height; i--; ) {
 165                 shift = val = 0;
 166                 l = 8;
 167                 j = image->width;
 168                 dst = (u32 __iomem *) dst1;
 169                 s = src;
 170
 171                 /* write leading bits */
 172                 if (start_index) {
 173                         u32 start_mask = ~(SHIFT_HIGH(~(u32)0, start_index));
 174                         val = FB_READL(dst) & start_mask;
 175                         shift = start_index;
 176                 }
 177
 178                 while (j--) {
 179                         l--;
 180                         color = (*s & (1 << l)) ? fgcolor : bgcolor;
 181                         color <<= LEFT_POS(bpp);
 182                         val |= SHIFT_HIGH(color, shift);
 183
 184                         /* Did the bitshift spill bits to the next long? */
 185                         if (shift >= null_bits) {
 186                                 FB_WRITEL(val, dst++);
 187                                 val = (shift == null_bits) ? 0 :
 188                                          SHIFT_LOW(color,32 - shift);
 189                         }
 190                         shift += bpp;
 191                         shift &= (32 - 1);
 192                         if (!l) { l = 8; s++; };
 193                 }
 194
 195                 /* write trailing bits */
 196                 if (shift) {
 197                         u32 end_mask = SHIFT_HIGH(~(u32)0, shift);
 198
 199                         FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
 200                 }
 201
 202                 dst1 += pitch;
 203                 src += spitch;
 204                 if (pitch_index) {
 205                         dst2 += pitch;
 206                         dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
 207                         start_index += pitch_index;
 208                         start_index &= 32 - 1;
 209                 }
 210
 211         }
 212 }
 213
 214 /*
 215  * fast_imageblit - optimized monochrome color expansion
 216  *
 217  * Only if:  bits_per_pixel == 8, 16, or 32
 218  *           image->width is divisible by pixel/dword (ppw);
 219  *           fix->line_legth is divisible by 4;
 220  *           beginning and end of a scanline is dword aligned
 221  */
 222 static inline void fast_imageblit(const struct fb_image *image, struct fb_info *p,
 223                                   u8 __iomem *dst1, u32 fgcolor,
 224                                   u32 bgcolor)
 225 {
 226         u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel;
 227         u32 ppw = 32/bpp, spitch = (image->width + 7)/8;
 228         u32 bit_mask, end_mask, eorx, shift;
 229         const char *s = image->data, *src;
 230         u32 __iomem *dst;
 231         u32 *tab = NULL;
 232         int i, j, k;
 233
 234         switch (bpp) {
 235         case 8:
 236                 tab = cfb_tab8;
 237                 break;
 238         case 16:
 239                 tab = cfb_tab16;
 240                 break;
 241         case 32:
 242                 tab = cfb_tab32;
 243                 break;
 244         }
 245
 246         for (i = ppw-1; i--; ) {
 247                 fgx <<= bpp;
 248                 bgx <<= bpp;
 249                 fgx |= fgcolor;
 250                 bgx |= bgcolor;
 251         }
 252
 253         bit_mask = (1 << ppw) - 1;
 254         eorx = fgx ^ bgx;
 255         k = image->width/ppw;
 256
 257         for (i = image->height; i--; ) {
 258                 dst = (u32 __iomem *) dst1, shift = 8; src = s;
 259
 260                 for (j = k; j--; ) {
 261                         shift -= ppw;
 262                         end_mask = tab[(*src >> shift) & bit_mask];
 263                         FB_WRITEL((end_mask & eorx)^bgx, dst++);
 264                         if (!shift) { shift = 8; src++; }
 265                 }
 266                 dst1 += p->fix.line_length;
 267                 s += spitch;
 268         }
 269 }
 270
 271 void cfb_imageblit(struct fb_info *p, const struct fb_image *image)
 272 {
 273         u32 fgcolor, bgcolor, start_index, bitstart, pitch_index = 0;
 274         u32 bpl = sizeof(u32), bpp = p->var.bits_per_pixel;
 275         u32 width = image->width, height = image->height;
 276         u32 dx = image->dx, dy = image->dy;
 277         int x2, y2, vxres, vyres;
 278         u8 __iomem *dst1;
 279
 280         if (p->state != FBINFO_STATE_RUNNING)
 281                 return;
 282
 283         vxres = p->var.xres_virtual;
 284         vyres = p->var.yres_virtual;
 285         /*
 286          * We could use hardware clipping but on many cards you get around
 287          * hardware clipping by writing to framebuffer directly like we are
 288          * doing here.
 289          */
 290         if (image->dx > vxres || image->dy > vyres)
 291                 return;
 292
 293         x2 = image->dx + image->width;
 294         y2 = image->dy + image->height;
 295         dx = image->dx > 0 ? image->dx : 0;
 296         dy = image->dy > 0 ? image->dy : 0;
 297         x2 = x2 < vxres ? x2 : vxres;
 298         y2 = y2 < vyres ? y2 : vyres;
 299         width  = x2 - dx;
 300         height = y2 - dy;
 301
 302         bitstart = (dy * p->fix.line_length * 8) + (dx * bpp);
 303         start_index = bitstart & (32 - 1);
 304         pitch_index = (p->fix.line_length & (bpl - 1)) * 8;
 305
 306         bitstart /= 8;
 307         bitstart &= ~(bpl - 1);
 308         dst1 = p->screen_base + bitstart;
 309
 310         if (p->fbops->fb_sync)
 311                 p->fbops->fb_sync(p);
 312
 313         if (image->depth == 1) {
 314                 if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
 315                     p->fix.visual == FB_VISUAL_DIRECTCOLOR) {
 316                         fgcolor = ((u32*)(p->pseudo_palette))[image->fg_color];
 317                         bgcolor = ((u32*)(p->pseudo_palette))[image->bg_color];
 318                 } else {
 319                         fgcolor = image->fg_color;
 320                         bgcolor = image->bg_color;
 321                 }
 322
 323                 if (32 % bpp == 0 && !start_index && !pitch_index &&
 324                     ((width & (32/bpp-1)) == 0) &&
 325                     bpp >= 8 && bpp <= 32)
 326                         fast_imageblit(image, p, dst1, fgcolor, bgcolor);
 327                 else
 328                         slow_imageblit(image, p, dst1, fgcolor, bgcolor,
 329                                         start_index, pitch_index);
 330         } else
 331                 color_imageblit(image, p, dst1, start_index, pitch_index);
 332 }
 333
 334 EXPORT_SYMBOL(cfb_imageblit);
 335
 336 MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
 337 MODULE_DESCRIPTION("Generic software accelerated imaging drawing");
 338 MODULE_LICENSE("GPL");
 339