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1/*2 * Fast C2P (Chunky-to-Planar) Conversion3 *4 * Copyright (C) 2003-2008 Geert Uytterhoeven5 *6 * This file is subject to the terms and conditions of the GNU General Public7 * License. See the file COPYING in the main directory of this archive8 * for more details.9 */10 11#include <linux/module.h>12#include <linux/string.h>13 14#include <linux/unaligned.h>15 16#include "c2p.h"17#include "c2p_core.h"18 19 20 /*21 * Perform a full C2P step on 16 8-bit pixels, stored in 4 32-bit words22 * containing23 * - 16 8-bit chunky pixels on input24 * - permutated planar data (2 planes per 32-bit word) on output25 */26 27static void c2p_16x8(u32 d[4])28{29 transp4(d, 8, 2);30 transp4(d, 1, 2);31 transp4x(d, 16, 2);32 transp4x(d, 2, 2);33 transp4(d, 4, 1);34}35 36 37 /*38 * Array containing the permutation indices of the planar data after c2p39 */40 41static const int perm_c2p_16x8[4] = { 1, 3, 0, 2 };42 43 44 /*45 * Store a full block of iplan2 data after c2p conversion46 */47 48static inline void store_iplan2(void *dst, u32 bpp, u32 d[4])49{50 int i;51 52 for (i = 0; i < bpp/2; i++, dst += 4)53 put_unaligned_be32(d[perm_c2p_16x8[i]], dst);54}55 56 57 /*58 * Store a partial block of iplan2 data after c2p conversion59 */60 61static inline void store_iplan2_masked(void *dst, u32 bpp, u32 d[4], u32 mask)62{63 int i;64 65 for (i = 0; i < bpp/2; i++, dst += 4)66 put_unaligned_be32(comp(d[perm_c2p_16x8[i]],67 get_unaligned_be32(dst), mask),68 dst);69}70 71 72 /*73 * c2p_iplan2 - Copy 8-bit chunky image data to an interleaved planar74 * frame buffer with 2 bytes of interleave75 * @dst: Starting address of the planar frame buffer76 * @dx: Horizontal destination offset (in pixels)77 * @dy: Vertical destination offset (in pixels)78 * @width: Image width (in pixels)79 * @height: Image height (in pixels)80 * @dst_nextline: Frame buffer offset to the next line (in bytes)81 * @src_nextline: Image offset to the next line (in bytes)82 * @bpp: Bits per pixel of the planar frame buffer (2, 4, or 8)83 */84 85void c2p_iplan2(void *dst, const void *src, u32 dx, u32 dy, u32 width,86 u32 height, u32 dst_nextline, u32 src_nextline, u32 bpp)87{88 union {89 u8 pixels[16];90 u32 words[4];91 } d;92 u32 dst_idx, first, last, w;93 const u8 *c;94 void *p;95 96 dst += dy*dst_nextline+(dx & ~15)*bpp;97 dst_idx = dx % 16;98 first = 0xffffU >> dst_idx;99 first |= first << 16;100 last = 0xffffU ^ (0xffffU >> ((dst_idx+width) % 16));101 last |= last << 16;102 while (height--) {103 c = src;104 p = dst;105 w = width;106 if (dst_idx+width <= 16) {107 /* Single destination word */108 first &= last;109 memset(d.pixels, 0, sizeof(d));110 memcpy(d.pixels+dst_idx, c, width);111 c += width;112 c2p_16x8(d.words);113 store_iplan2_masked(p, bpp, d.words, first);114 p += bpp*2;115 } else {116 /* Multiple destination words */117 w = width;118 /* Leading bits */119 if (dst_idx) {120 w = 16 - dst_idx;121 memset(d.pixels, 0, dst_idx);122 memcpy(d.pixels+dst_idx, c, w);123 c += w;124 c2p_16x8(d.words);125 store_iplan2_masked(p, bpp, d.words, first);126 p += bpp*2;127 w = width-w;128 }129 /* Main chunk */130 while (w >= 16) {131 memcpy(d.pixels, c, 16);132 c += 16;133 c2p_16x8(d.words);134 store_iplan2(p, bpp, d.words);135 p += bpp*2;136 w -= 16;137 }138 /* Trailing bits */139 w %= 16;140 if (w > 0) {141 memcpy(d.pixels, c, w);142 memset(d.pixels+w, 0, 16-w);143 c2p_16x8(d.words);144 store_iplan2_masked(p, bpp, d.words, last);145 }146 }147 src += src_nextline;148 dst += dst_nextline;149 }150}151EXPORT_SYMBOL_GPL(c2p_iplan2);152 153MODULE_LICENSE("GPL");154