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 */