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-rw-r--r--drivers/video/fbdev/c2p_planar.c156
1 files changed, 156 insertions, 0 deletions
diff --git a/drivers/video/fbdev/c2p_planar.c b/drivers/video/fbdev/c2p_planar.c
new file mode 100644
index 000000000000..ec7ac8526f06
--- /dev/null
+++ b/drivers/video/fbdev/c2p_planar.c
@@ -0,0 +1,156 @@
+/*
+ * Fast C2P (Chunky-to-Planar) Conversion
+ *
+ * Copyright (C) 2003-2008 Geert Uytterhoeven
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+
+#include <asm/unaligned.h>
+
+#include "c2p.h"
+#include "c2p_core.h"
+
+
+ /*
+ * Perform a full C2P step on 32 8-bit pixels, stored in 8 32-bit words
+ * containing
+ * - 32 8-bit chunky pixels on input
+ * - permutated planar data (1 plane per 32-bit word) on output
+ */
+
+static void c2p_32x8(u32 d[8])
+{
+ transp8(d, 16, 4);
+ transp8(d, 8, 2);
+ transp8(d, 4, 1);
+ transp8(d, 2, 4);
+ transp8(d, 1, 2);
+}
+
+
+ /*
+ * Array containing the permutation indices of the planar data after c2p
+ */
+
+static const int perm_c2p_32x8[8] = { 7, 5, 3, 1, 6, 4, 2, 0 };
+
+
+ /*
+ * Store a full block of planar data after c2p conversion
+ */
+
+static inline void store_planar(void *dst, u32 dst_inc, u32 bpp, u32 d[8])
+{
+ int i;
+
+ for (i = 0; i < bpp; i++, dst += dst_inc)
+ put_unaligned_be32(d[perm_c2p_32x8[i]], dst);
+}
+
+
+ /*
+ * Store a partial block of planar data after c2p conversion
+ */
+
+static inline void store_planar_masked(void *dst, u32 dst_inc, u32 bpp,
+ u32 d[8], u32 mask)
+{
+ int i;
+
+ for (i = 0; i < bpp; i++, dst += dst_inc)
+ put_unaligned_be32(comp(d[perm_c2p_32x8[i]],
+ get_unaligned_be32(dst), mask),
+ dst);
+}
+
+
+ /*
+ * c2p_planar - Copy 8-bit chunky image data to a planar frame buffer
+ * @dst: Starting address of the planar frame buffer
+ * @dx: Horizontal destination offset (in pixels)
+ * @dy: Vertical destination offset (in pixels)
+ * @width: Image width (in pixels)
+ * @height: Image height (in pixels)
+ * @dst_nextline: Frame buffer offset to the next line (in bytes)
+ * @dst_nextplane: Frame buffer offset to the next plane (in bytes)
+ * @src_nextline: Image offset to the next line (in bytes)
+ * @bpp: Bits per pixel of the planar frame buffer (1-8)
+ */
+
+void c2p_planar(void *dst, const void *src, u32 dx, u32 dy, u32 width,
+ u32 height, u32 dst_nextline, u32 dst_nextplane,
+ u32 src_nextline, u32 bpp)
+{
+ union {
+ u8 pixels[32];
+ u32 words[8];
+ } d;
+ u32 dst_idx, first, last, w;
+ const u8 *c;
+ void *p;
+
+ dst += dy*dst_nextline+(dx & ~31);
+ dst_idx = dx % 32;
+ first = 0xffffffffU >> dst_idx;
+ last = ~(0xffffffffU >> ((dst_idx+width) % 32));
+ while (height--) {
+ c = src;
+ p = dst;
+ w = width;
+ if (dst_idx+width <= 32) {
+ /* Single destination word */
+ first &= last;
+ memset(d.pixels, 0, sizeof(d));
+ memcpy(d.pixels+dst_idx, c, width);
+ c += width;
+ c2p_32x8(d.words);
+ store_planar_masked(p, dst_nextplane, bpp, d.words,
+ first);
+ p += 4;
+ } else {
+ /* Multiple destination words */
+ w = width;
+ /* Leading bits */
+ if (dst_idx) {
+ w = 32 - dst_idx;
+ memset(d.pixels, 0, dst_idx);
+ memcpy(d.pixels+dst_idx, c, w);
+ c += w;
+ c2p_32x8(d.words);
+ store_planar_masked(p, dst_nextplane, bpp,
+ d.words, first);
+ p += 4;
+ w = width-w;
+ }
+ /* Main chunk */
+ while (w >= 32) {
+ memcpy(d.pixels, c, 32);
+ c += 32;
+ c2p_32x8(d.words);
+ store_planar(p, dst_nextplane, bpp, d.words);
+ p += 4;
+ w -= 32;
+ }
+ /* Trailing bits */
+ w %= 32;
+ if (w > 0) {
+ memcpy(d.pixels, c, w);
+ memset(d.pixels+w, 0, 32-w);
+ c2p_32x8(d.words);
+ store_planar_masked(p, dst_nextplane, bpp,
+ d.words, last);
+ }
+ }
+ src += src_nextline;
+ dst += dst_nextline;
+ }
+}
+EXPORT_SYMBOL_GPL(c2p_planar);
+
+MODULE_LICENSE("GPL");
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