drivers/video/fbdev/core/fb_draw.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _FB_DRAW_H
   3 #define _FB_DRAW_H
   4
   5 #include <asm/types.h>
   6 #include <linux/fb.h>
   7 #include <linux/bug.h>
   8
   9     /*
  10      *  Compose two values, using a bitmask as decision value
  11      *  This is equivalent to (a & mask) | (b & ~mask)
  12      */
  13
  14 static inline unsigned long
  15 comp(unsigned long a, unsigned long b, unsigned long mask)
  16 {
  17     return ((a ^ b) & mask) ^ b;
  18 }
  19
  20     /*
  21      *  Create a pattern with the given pixel's color
  22      */
  23
  24 #if BITS_PER_LONG == 64
  25 static inline unsigned long
  26 pixel_to_pat( u32 bpp, u32 pixel)
  27 {
  28         switch (bpp) {
  29         case 1:
  30                 return 0xfffffffffffffffful*pixel;
  31         case 2:
  32                 return 0x5555555555555555ul*pixel;
  33         case 4:
  34                 return 0x1111111111111111ul*pixel;
  35         case 8:
  36                 return 0x0101010101010101ul*pixel;
  37         case 12:
  38                 return 0x1001001001001001ul*pixel;
  39         case 16:
  40                 return 0x0001000100010001ul*pixel;
  41         case 24:
  42                 return 0x0001000001000001ul*pixel;
  43         case 32:
  44                 return 0x0000000100000001ul*pixel;
  45         default:
  46                 WARN(1, "pixel_to_pat(): unsupported pixelformat %d\n", bpp);
  47                 return 0;
  48     }
  49 }
  50 #else
  51 static inline unsigned long
  52 pixel_to_pat( u32 bpp, u32 pixel)
  53 {
  54         switch (bpp) {
  55         case 1:
  56                 return 0xfffffffful*pixel;
  57         case 2:
  58                 return 0x55555555ul*pixel;
  59         case 4:
  60                 return 0x11111111ul*pixel;
  61         case 8:
  62                 return 0x01010101ul*pixel;
  63         case 12:
  64                 return 0x01001001ul*pixel;
  65         case 16:
  66                 return 0x00010001ul*pixel;
  67         case 24:
  68                 return 0x01000001ul*pixel;
  69         case 32:
  70                 return 0x00000001ul*pixel;
  71         default:
  72                 WARN(1, "pixel_to_pat(): unsupported pixelformat %d\n", bpp);
  73                 return 0;
  74     }
  75 }
  76 #endif
  77
  78 #ifdef CONFIG_FB_CFB_REV_PIXELS_IN_BYTE
  79 #if BITS_PER_LONG == 64
  80 #define REV_PIXELS_MASK1 0x5555555555555555ul
  81 #define REV_PIXELS_MASK2 0x3333333333333333ul
  82 #define REV_PIXELS_MASK4 0x0f0f0f0f0f0f0f0ful
  83 #else
  84 #define REV_PIXELS_MASK1 0x55555555ul
  85 #define REV_PIXELS_MASK2 0x33333333ul
  86 #define REV_PIXELS_MASK4 0x0f0f0f0ful
  87 #endif
  88
  89 static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
  90                                                   u32 bswapmask)
  91 {
  92         if (bswapmask & 1)
  93                 val = comp(val >> 1, val << 1, REV_PIXELS_MASK1);
  94         if (bswapmask & 2)
  95                 val = comp(val >> 2, val << 2, REV_PIXELS_MASK2);
  96         if (bswapmask & 3)
  97                 val = comp(val >> 4, val << 4, REV_PIXELS_MASK4);
  98         return val;
  99 }
 100
 101 static inline u32 fb_shifted_pixels_mask_u32(struct fb_info *p, u32 index,
 102                                              u32 bswapmask)
 103 {
 104         u32 mask;
 105
 106         if (!bswapmask) {
 107                 mask = FB_SHIFT_HIGH(p, ~(u32)0, index);
 108         } else {
 109                 mask = 0xff << FB_LEFT_POS(p, 8);
 110                 mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
 111                 mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
 112 #if defined(__i386__) || defined(__x86_64__)
 113                 /* Shift argument is limited to 0 - 31 on x86 based CPU's */
 114                 if(index + bswapmask < 32)
 115 #endif
 116                         mask |= FB_SHIFT_HIGH(p, ~(u32)0,
 117                                         (index + bswapmask) & ~(bswapmask));
 118         }
 119         return mask;
 120 }
 121
 122 static inline unsigned long fb_shifted_pixels_mask_long(struct fb_info *p,
 123                                                         u32 index,
 124                                                         u32 bswapmask)
 125 {
 126         unsigned long mask;
 127
 128         if (!bswapmask) {
 129                 mask = FB_SHIFT_HIGH(p, ~0UL, index);
 130         } else {
 131                 mask = 0xff << FB_LEFT_POS(p, 8);
 132                 mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
 133                 mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
 134 #if defined(__i386__) || defined(__x86_64__)
 135                 /* Shift argument is limited to 0 - 31 on x86 based CPU's */
 136                 if(index + bswapmask < BITS_PER_LONG)
 137 #endif
 138                         mask |= FB_SHIFT_HIGH(p, ~0UL,
 139                                         (index + bswapmask) & ~(bswapmask));
 140         }
 141         return mask;
 142 }
 143
 144
 145 static inline u32 fb_compute_bswapmask(struct fb_info *info)
 146 {
 147         u32 bswapmask = 0;
 148         unsigned bpp = info->var.bits_per_pixel;
 149
 150         if ((bpp < 8) && (info->var.nonstd & FB_NONSTD_REV_PIX_IN_B)) {
 151                 /*
 152                  * Reversed order of pixel layout in bytes
 153                  * works only for 1, 2 and 4 bpp
 154                  */
 155                 bswapmask = 7 - bpp + 1;
 156         }
 157         return bswapmask;
 158 }
 159
 160 #else /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
 161
 162 static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
 163                                                   u32 bswapmask)
 164 {
 165         return val;
 166 }
 167
 168 #define fb_shifted_pixels_mask_u32(p, i, b) FB_SHIFT_HIGH((p), ~(u32)0, (i))
 169 #define fb_shifted_pixels_mask_long(p, i, b) FB_SHIFT_HIGH((p), ~0UL, (i))
 170 #define fb_compute_bswapmask(...) 0
 171
 172 #endif  /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
 173
 174 #define cpu_to_le_long _cpu_to_le_long(BITS_PER_LONG)
 175 #define _cpu_to_le_long(x) __cpu_to_le_long(x)
 176 #define __cpu_to_le_long(x) cpu_to_le##x
 177
 178 #define le_long_to_cpu _le_long_to_cpu(BITS_PER_LONG)
 179 #define _le_long_to_cpu(x) __le_long_to_cpu(x)
 180 #define __le_long_to_cpu(x) le##x##_to_cpu
 181
 182 static inline unsigned long rolx(unsigned long word, unsigned int shift, unsigned int x)
 183 {
 184         return (word << shift) | (word >> (x - shift));
 185 }
 186
 187 #endif /* FB_DRAW_H */