drivers/video/fb_draw.h

   1 #ifndef _FB_DRAW_H
   2 #define _FB_DRAW_H
   3
   4 #include <asm/types.h>
   5 #include <linux/fb.h>
   6
   7     /*
   8      *  Compose two values, using a bitmask as decision value
   9      *  This is equivalent to (a & mask) | (b & ~mask)
  10      */
  11
  12 static inline unsigned long
  13 comp(unsigned long a, unsigned long b, unsigned long mask)
  14 {
  15     return ((a ^ b) & mask) ^ b;
  16 }
  17
  18     /*
  19      *  Create a pattern with the given pixel's color
  20      */
  21
  22 #if BITS_PER_LONG == 64
  23 static inline unsigned long
  24 pixel_to_pat( u32 bpp, u32 pixel)
  25 {
  26         switch (bpp) {
  27         case 1:
  28                 return 0xfffffffffffffffful*pixel;
  29         case 2:
  30                 return 0x5555555555555555ul*pixel;
  31         case 4:
  32                 return 0x1111111111111111ul*pixel;
  33         case 8:
  34                 return 0x0101010101010101ul*pixel;
  35         case 12:
  36                 return 0x0001001001001001ul*pixel;
  37         case 16:
  38                 return 0x0001000100010001ul*pixel;
  39         case 24:
  40                 return 0x0000000001000001ul*pixel;
  41         case 32:
  42                 return 0x0000000100000001ul*pixel;
  43         default:
  44                 panic("pixel_to_pat(): unsupported pixelformat\n");
  45     }
  46 }
  47 #else
  48 static inline unsigned long
  49 pixel_to_pat( u32 bpp, u32 pixel)
  50 {
  51         switch (bpp) {
  52         case 1:
  53                 return 0xfffffffful*pixel;
  54         case 2:
  55                 return 0x55555555ul*pixel;
  56         case 4:
  57                 return 0x11111111ul*pixel;
  58         case 8:
  59                 return 0x01010101ul*pixel;
  60         case 12:
  61                 return 0x00001001ul*pixel;
  62         case 16:
  63                 return 0x00010001ul*pixel;
  64         case 24:
  65                 return 0x00000001ul*pixel;
  66         case 32:
  67                 return 0x00000001ul*pixel;
  68         default:
  69                 panic("pixel_to_pat(): unsupported pixelformat\n");
  70     }
  71 }
  72 #endif
  73
  74 #ifdef CONFIG_FB_CFB_REV_PIXELS_IN_BYTE
  75 #if BITS_PER_LONG == 64
  76 #define REV_PIXELS_MASK1 0x5555555555555555ul
  77 #define REV_PIXELS_MASK2 0x3333333333333333ul
  78 #define REV_PIXELS_MASK4 0x0f0f0f0f0f0f0f0ful
  79 #else
  80 #define REV_PIXELS_MASK1 0x55555555ul
  81 #define REV_PIXELS_MASK2 0x33333333ul
  82 #define REV_PIXELS_MASK4 0x0f0f0f0ful
  83 #endif
  84
  85 static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
  86                                                   u32 bswapmask)
  87 {
  88         if (bswapmask & 1)
  89                 val = comp(val >> 1, val << 1, REV_PIXELS_MASK1);
  90         if (bswapmask & 2)
  91                 val = comp(val >> 2, val << 2, REV_PIXELS_MASK2);
  92         if (bswapmask & 3)
  93                 val = comp(val >> 4, val << 4, REV_PIXELS_MASK4);
  94         return val;
  95 }
  96
  97 static inline u32 fb_shifted_pixels_mask_u32(struct fb_info *p, u32 index,
  98                                              u32 bswapmask)
  99 {
 100         u32 mask;
 101
 102         if (!bswapmask) {
 103                 mask = FB_SHIFT_HIGH(p, ~(u32)0, index);
 104         } else {
 105                 mask = 0xff << FB_LEFT_POS(p, 8);
 106                 mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
 107                 mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
 108 #if defined(__i386__) || defined(__x86_64__)
 109                 /* Shift argument is limited to 0 - 31 on x86 based CPU's */
 110                 if(index + bswapmask < 32)
 111 #endif
 112                         mask |= FB_SHIFT_HIGH(p, ~(u32)0,
 113                                         (index + bswapmask) & ~(bswapmask));
 114         }
 115         return mask;
 116 }
 117
 118 static inline unsigned long fb_shifted_pixels_mask_long(struct fb_info *p,
 119                                                         u32 index,
 120                                                         u32 bswapmask)
 121 {
 122         unsigned long mask;
 123
 124         if (!bswapmask) {
 125                 mask = FB_SHIFT_HIGH(p, ~0UL, index);
 126         } else {
 127                 mask = 0xff << FB_LEFT_POS(p, 8);
 128                 mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
 129                 mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
 130 #if defined(__i386__) || defined(__x86_64__)
 131                 /* Shift argument is limited to 0 - 31 on x86 based CPU's */
 132                 if(index + bswapmask < BITS_PER_LONG)
 133 #endif
 134                         mask |= FB_SHIFT_HIGH(p, ~0UL,
 135                                         (index + bswapmask) & ~(bswapmask));
 136         }
 137         return mask;
 138 }
 139
 140
 141 static inline u32 fb_compute_bswapmask(struct fb_info *info)
 142 {
 143         u32 bswapmask = 0;
 144         unsigned bpp = info->var.bits_per_pixel;
 145
 146         if ((bpp < 8) && (info->var.nonstd & FB_NONSTD_REV_PIX_IN_B)) {
 147                 /*
 148                  * Reversed order of pixel layout in bytes
 149                  * works only for 1, 2 and 4 bpp
 150                  */
 151                 bswapmask = 7 - bpp + 1;
 152         }
 153         return bswapmask;
 154 }
 155
 156 #else /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
 157
 158 static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
 159                                                   u32 bswapmask)
 160 {
 161         return val;
 162 }
 163
 164 #define fb_shifted_pixels_mask_u32(p, i, b) FB_SHIFT_HIGH((p), ~(u32)0, (i))
 165 #define fb_shifted_pixels_mask_long(p, i, b) FB_SHIFT_HIGH((p), ~0UL, (i))
 166 #define fb_compute_bswapmask(...) 0
 167
 168 #endif  /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
 169
 170 #endif /* FB_DRAW_H */