LXR linux/drivers/video/fbdev/core/fb

   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
  14static inline unsigned long
  15comp(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
  25static inline unsigned long
  26pixel_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
  51static inline unsigned long
  52pixel_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
  89static 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
 101static 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
 122static 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
 145static 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
 162static 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
 182static 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 */
 188