root/drivers/video/fbdev/core/cfbimgblt.c

DEFINITIONS

1. color_imageblit
2. slow_imageblit
3. fast_imageblit
4. cfb_imageblit

   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/module.h>
  33 #include <linux/string.h>
  34 #include <linux/fb.h>
  35 #include <asm/types.h>
  36 #include "fb_draw.h"
  37 
  38 #define DEBUG
  39 
  40 #ifdef DEBUG
  41 #define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt,__func__,## args)
  42 #else
  43 #define DPRINTK(fmt, args...)
  44 #endif
  45 
  46 static const u32 cfb_tab8_be[] = {
  47     0x00000000,0x000000ff,0x0000ff00,0x0000ffff,
  48     0x00ff0000,0x00ff00ff,0x00ffff00,0x00ffffff,
  49     0xff000000,0xff0000ff,0xff00ff00,0xff00ffff,
  50     0xffff0000,0xffff00ff,0xffffff00,0xffffffff
  51 };
  52 
  53 static const u32 cfb_tab8_le[] = {
  54     0x00000000,0xff000000,0x00ff0000,0xffff0000,
  55     0x0000ff00,0xff00ff00,0x00ffff00,0xffffff00,
  56     0x000000ff,0xff0000ff,0x00ff00ff,0xffff00ff,
  57     0x0000ffff,0xff00ffff,0x00ffffff,0xffffffff
  58 };
  59 
  60 static const u32 cfb_tab16_be[] = {
  61     0x00000000, 0x0000ffff, 0xffff0000, 0xffffffff
  62 };
  63 
  64 static const u32 cfb_tab16_le[] = {
  65     0x00000000, 0xffff0000, 0x0000ffff, 0xffffffff
  66 };
  67 
  68 static const u32 cfb_tab32[] = {
  69         0x00000000, 0xffffffff
  70 };
  71 
  72 #define FB_WRITEL fb_writel
  73 #define FB_READL  fb_readl
  74 
  75 static inline void color_imageblit(const struct fb_image *image, 
  76                                    struct fb_info *p, u8 __iomem *dst1, 
  77                                    u32 start_index,
  78                                    u32 pitch_index)
  79 {
  80         /* Draw the penguin */
  81         u32 __iomem *dst, *dst2;
  82         u32 color = 0, val, shift;
  83         int i, n, bpp = p->var.bits_per_pixel;
  84         u32 null_bits = 32 - bpp;
  85         u32 *palette = (u32 *) p->pseudo_palette;
  86         const u8 *src = image->data;
  87         u32 bswapmask = fb_compute_bswapmask(p);
  88 
  89         dst2 = (u32 __iomem *) dst1;
  90         for (i = image->height; i--; ) {
  91                 n = image->width;
  92                 dst = (u32 __iomem *) dst1;
  93                 shift = 0;
  94                 val = 0;
  95                 
  96                 if (start_index) {
  97                         u32 start_mask = ~fb_shifted_pixels_mask_u32(p,
  98                                                 start_index, bswapmask);
  99                         val = FB_READL(dst) & start_mask;
 100                         shift = start_index;
 101                 }
 102                 while (n--) {
 103                         if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
 104                             p->fix.visual == FB_VISUAL_DIRECTCOLOR )
 105                                 color = palette[*src];
 106                         else
 107                                 color = *src;
 108                         color <<= FB_LEFT_POS(p, bpp);
 109                         val |= FB_SHIFT_HIGH(p, color, shift ^ bswapmask);
 110                         if (shift >= null_bits) {
 111                                 FB_WRITEL(val, dst++);
 112         
 113                                 val = (shift == null_bits) ? 0 : 
 114                                         FB_SHIFT_LOW(p, color, 32 - shift);
 115                         }
 116                         shift += bpp;
 117                         shift &= (32 - 1);
 118                         src++;
 119                 }
 120                 if (shift) {
 121                         u32 end_mask = fb_shifted_pixels_mask_u32(p, shift,
 122                                                 bswapmask);
 123 
 124                         FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
 125                 }
 126                 dst1 += p->fix.line_length;
 127                 if (pitch_index) {
 128                         dst2 += p->fix.line_length;
 129                         dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
 130 
 131                         start_index += pitch_index;
 132                         start_index &= 32 - 1;
 133                 }
 134         }
 135 }
 136 
 137 static inline void slow_imageblit(const struct fb_image *image, struct fb_info *p, 
 138                                   u8 __iomem *dst1, u32 fgcolor,
 139                                   u32 bgcolor, 
 140                                   u32 start_index,
 141                                   u32 pitch_index)
 142 {
 143         u32 shift, color = 0, bpp = p->var.bits_per_pixel;
 144         u32 __iomem *dst, *dst2;
 145         u32 val, pitch = p->fix.line_length;
 146         u32 null_bits = 32 - bpp;
 147         u32 spitch = (image->width+7)/8;
 148         const u8 *src = image->data, *s;
 149         u32 i, j, l;
 150         u32 bswapmask = fb_compute_bswapmask(p);
 151 
 152         dst2 = (u32 __iomem *) dst1;
 153         fgcolor <<= FB_LEFT_POS(p, bpp);
 154         bgcolor <<= FB_LEFT_POS(p, bpp);
 155 
 156         for (i = image->height; i--; ) {
 157                 shift = val = 0;
 158                 l = 8;
 159                 j = image->width;
 160                 dst = (u32 __iomem *) dst1;
 161                 s = src;
 162 
 163                 /* write leading bits */
 164                 if (start_index) {
 165                         u32 start_mask = ~fb_shifted_pixels_mask_u32(p,
 166                                                 start_index, bswapmask);
 167                         val = FB_READL(dst) & start_mask;
 168                         shift = start_index;
 169                 }
 170 
 171                 while (j--) {
 172                         l--;
 173                         color = (*s & (1 << l)) ? fgcolor : bgcolor;
 174                         val |= FB_SHIFT_HIGH(p, color, shift ^ bswapmask);
 175                         
 176                         /* Did the bitshift spill bits to the next long? */
 177                         if (shift >= null_bits) {
 178                                 FB_WRITEL(val, dst++);
 179                                 val = (shift == null_bits) ? 0 :
 180                                         FB_SHIFT_LOW(p, color, 32 - shift);
 181                         }
 182                         shift += bpp;
 183                         shift &= (32 - 1);
 184                         if (!l) { l = 8; s++; }
 185                 }
 186 
 187                 /* write trailing bits */
 188                 if (shift) {
 189                         u32 end_mask = fb_shifted_pixels_mask_u32(p, shift,
 190                                                 bswapmask);
 191 
 192                         FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
 193                 }
 194                 
 195                 dst1 += pitch;
 196                 src += spitch;  
 197                 if (pitch_index) {
 198                         dst2 += pitch;
 199                         dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
 200                         start_index += pitch_index;
 201                         start_index &= 32 - 1;
 202                 }
 203                 
 204         }
 205 }
 206 
 207 /*
 208  * fast_imageblit - optimized monochrome color expansion
 209  *
 210  * Only if:  bits_per_pixel == 8, 16, or 32
 211  *           image->width is divisible by pixel/dword (ppw);
 212  *           fix->line_legth is divisible by 4;
 213  *           beginning and end of a scanline is dword aligned
 214  */
 215 static inline void fast_imageblit(const struct fb_image *image, struct fb_info *p, 
 216                                   u8 __iomem *dst1, u32 fgcolor, 
 217                                   u32 bgcolor) 
 218 {
 219         u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel;
 220         u32 ppw = 32/bpp, spitch = (image->width + 7)/8;
 221         u32 bit_mask, end_mask, eorx, shift;
 222         const char *s = image->data, *src;
 223         u32 __iomem *dst;
 224         const u32 *tab = NULL;
 225         int i, j, k;
 226 
 227         switch (bpp) {
 228         case 8:
 229                 tab = fb_be_math(p) ? cfb_tab8_be : cfb_tab8_le;
 230                 break;
 231         case 16:
 232                 tab = fb_be_math(p) ? cfb_tab16_be : cfb_tab16_le;
 233                 break;
 234         case 32:
 235         default:
 236                 tab = cfb_tab32;
 237                 break;
 238         }
 239 
 240         for (i = ppw-1; i--; ) {
 241                 fgx <<= bpp;
 242                 bgx <<= bpp;
 243                 fgx |= fgcolor;
 244                 bgx |= bgcolor;
 245         }
 246         
 247         bit_mask = (1 << ppw) - 1;
 248         eorx = fgx ^ bgx;
 249         k = image->width/ppw;
 250 
 251         for (i = image->height; i--; ) {
 252                 dst = (u32 __iomem *) dst1, shift = 8; src = s;
 253                 
 254                 for (j = k; j--; ) {
 255                         shift -= ppw;
 256                         end_mask = tab[(*src >> shift) & bit_mask];
 257                         FB_WRITEL((end_mask & eorx)^bgx, dst++);
 258                         if (!shift) { shift = 8; src++; }               
 259                 }
 260                 dst1 += p->fix.line_length;
 261                 s += spitch;
 262         }
 263 }       
 264         
 265 void cfb_imageblit(struct fb_info *p, const struct fb_image *image)
 266 {
 267         u32 fgcolor, bgcolor, start_index, bitstart, pitch_index = 0;
 268         u32 bpl = sizeof(u32), bpp = p->var.bits_per_pixel;
 269         u32 width = image->width;
 270         u32 dx = image->dx, dy = image->dy;
 271         u8 __iomem *dst1;
 272 
 273         if (p->state != FBINFO_STATE_RUNNING)
 274                 return;
 275 
 276         bitstart = (dy * p->fix.line_length * 8) + (dx * bpp);
 277         start_index = bitstart & (32 - 1);
 278         pitch_index = (p->fix.line_length & (bpl - 1)) * 8;
 279 
 280         bitstart /= 8;
 281         bitstart &= ~(bpl - 1);
 282         dst1 = p->screen_base + bitstart;
 283 
 284         if (p->fbops->fb_sync)
 285                 p->fbops->fb_sync(p);
 286 
 287         if (image->depth == 1) {
 288                 if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
 289                     p->fix.visual == FB_VISUAL_DIRECTCOLOR) {
 290                         fgcolor = ((u32*)(p->pseudo_palette))[image->fg_color];
 291                         bgcolor = ((u32*)(p->pseudo_palette))[image->bg_color];
 292                 } else {
 293                         fgcolor = image->fg_color;
 294                         bgcolor = image->bg_color;
 295                 }       
 296                 
 297                 if (32 % bpp == 0 && !start_index && !pitch_index && 
 298                     ((width & (32/bpp-1)) == 0) &&
 299                     bpp >= 8 && bpp <= 32)                      
 300                         fast_imageblit(image, p, dst1, fgcolor, bgcolor);
 301                 else 
 302                         slow_imageblit(image, p, dst1, fgcolor, bgcolor,
 303                                         start_index, pitch_index);
 304         } else
 305                 color_imageblit(image, p, dst1, start_index, pitch_index);
 306 }
 307 
 308 EXPORT_SYMBOL(cfb_imageblit);
 309 
 310 MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
 311 MODULE_DESCRIPTION("Generic software accelerated imaging drawing");
 312 MODULE_LICENSE("GPL");
 313