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