Merge git://git.infradead.org/mtd-2.6
[linux-2.6] / 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 */