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path: root/drivers/video/fbdev/core/cfbcopyarea.c
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Diffstat (limited to 'drivers/video/fbdev/core/cfbcopyarea.c')
-rw-r--r--drivers/video/fbdev/core/cfbcopyarea.c434
1 files changed, 434 insertions, 0 deletions
diff --git a/drivers/video/fbdev/core/cfbcopyarea.c b/drivers/video/fbdev/core/cfbcopyarea.c
new file mode 100644
index 00000000000..bcb57235fcc
--- /dev/null
+++ b/drivers/video/fbdev/core/cfbcopyarea.c
@@ -0,0 +1,434 @@
+/*
+ * Generic function for frame buffer with packed pixels of any depth.
+ *
+ * Copyright (C) 1999-2005 James Simmons <jsimmons@www.infradead.org>
+ *
+ * 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.
+ *
+ * NOTES:
+ *
+ * This is for cfb packed pixels. Iplan and such are incorporated in the
+ * drivers that need them.
+ *
+ * FIXME
+ *
+ * Also need to add code to deal with cards endians that are different than
+ * the native cpu endians. I also need to deal with MSB position in the word.
+ *
+ * The two functions or copying forward and backward could be split up like
+ * the ones for filling, i.e. in aligned and unaligned versions. This would
+ * help moving some redundant computations and branches out of the loop, too.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/fb.h>
+#include <asm/types.h>
+#include <asm/io.h>
+#include "fb_draw.h"
+
+#if BITS_PER_LONG == 32
+# define FB_WRITEL fb_writel
+# define FB_READL fb_readl
+#else
+# define FB_WRITEL fb_writeq
+# define FB_READL fb_readq
+#endif
+
+ /*
+ * Generic bitwise copy algorithm
+ */
+
+static void
+bitcpy(struct fb_info *p, unsigned long __iomem *dst, unsigned dst_idx,
+ const unsigned long __iomem *src, unsigned src_idx, int bits,
+ unsigned n, u32 bswapmask)
+{
+ unsigned long first, last;
+ int const shift = dst_idx-src_idx;
+
+#if 0
+ /*
+ * If you suspect bug in this function, compare it with this simple
+ * memmove implementation.
+ */
+ fb_memmove((char *)dst + ((dst_idx & (bits - 1))) / 8,
+ (char *)src + ((src_idx & (bits - 1))) / 8, n / 8);
+ return;
+#endif
+
+ first = fb_shifted_pixels_mask_long(p, dst_idx, bswapmask);
+ last = ~fb_shifted_pixels_mask_long(p, (dst_idx+n) % bits, bswapmask);
+
+ if (!shift) {
+ // Same alignment for source and dest
+
+ if (dst_idx+n <= bits) {
+ // Single word
+ if (last)
+ first &= last;
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), first), dst);
+ } else {
+ // Multiple destination words
+
+ // Leading bits
+ if (first != ~0UL) {
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), first), dst);
+ dst++;
+ src++;
+ n -= bits - dst_idx;
+ }
+
+ // Main chunk
+ n /= bits;
+ while (n >= 8) {
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ FB_WRITEL(FB_READL(src++), dst++);
+ n -= 8;
+ }
+ while (n--)
+ FB_WRITEL(FB_READL(src++), dst++);
+
+ // Trailing bits
+ if (last)
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), last), dst);
+ }
+ } else {
+ /* Different alignment for source and dest */
+ unsigned long d0, d1;
+ int m;
+
+ int const left = shift & (bits - 1);
+ int const right = -shift & (bits - 1);
+
+ if (dst_idx+n <= bits) {
+ // Single destination word
+ if (last)
+ first &= last;
+ d0 = FB_READL(src);
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ if (shift > 0) {
+ // Single source word
+ d0 <<= left;
+ } else if (src_idx+n <= bits) {
+ // Single source word
+ d0 >>= right;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src + 1);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+ d0 = d0 >> right | d1 << left;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), first), dst);
+ } else {
+ // Multiple destination words
+ /** We must always remember the last value read, because in case
+ SRC and DST overlap bitwise (e.g. when moving just one pixel in
+ 1bpp), we always collect one full long for DST and that might
+ overlap with the current long from SRC. We store this value in
+ 'd0'. */
+ d0 = FB_READL(src++);
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ // Leading bits
+ if (shift > 0) {
+ // Single source word
+ d1 = d0;
+ d0 <<= left;
+ n -= bits - dst_idx;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src++);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+
+ d0 = d0 >> right | d1 << left;
+ n -= bits - dst_idx;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), first), dst);
+ d0 = d1;
+ dst++;
+
+ // Main chunk
+ m = n % bits;
+ n /= bits;
+ while ((n >= 4) && !bswapmask) {
+ d1 = FB_READL(src++);
+ FB_WRITEL(d0 >> right | d1 << left, dst++);
+ d0 = d1;
+ d1 = FB_READL(src++);
+ FB_WRITEL(d0 >> right | d1 << left, dst++);
+ d0 = d1;
+ d1 = FB_READL(src++);
+ FB_WRITEL(d0 >> right | d1 << left, dst++);
+ d0 = d1;
+ d1 = FB_READL(src++);
+ FB_WRITEL(d0 >> right | d1 << left, dst++);
+ d0 = d1;
+ n -= 4;
+ }
+ while (n--) {
+ d1 = FB_READL(src++);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+ d0 = d0 >> right | d1 << left;
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(d0, dst++);
+ d0 = d1;
+ }
+
+ // Trailing bits
+ if (m) {
+ if (m <= bits - right) {
+ // Single source word
+ d0 >>= right;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src);
+ d1 = fb_rev_pixels_in_long(d1,
+ bswapmask);
+ d0 = d0 >> right | d1 << left;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), last), dst);
+ }
+ }
+ }
+}
+
+ /*
+ * Generic bitwise copy algorithm, operating backward
+ */
+
+static void
+bitcpy_rev(struct fb_info *p, unsigned long __iomem *dst, unsigned dst_idx,
+ const unsigned long __iomem *src, unsigned src_idx, int bits,
+ unsigned n, u32 bswapmask)
+{
+ unsigned long first, last;
+ int shift;
+
+#if 0
+ /*
+ * If you suspect bug in this function, compare it with this simple
+ * memmove implementation.
+ */
+ fb_memmove((char *)dst + ((dst_idx & (bits - 1))) / 8,
+ (char *)src + ((src_idx & (bits - 1))) / 8, n / 8);
+ return;
+#endif
+
+ dst += (dst_idx + n - 1) / bits;
+ src += (src_idx + n - 1) / bits;
+ dst_idx = (dst_idx + n - 1) % bits;
+ src_idx = (src_idx + n - 1) % bits;
+
+ shift = dst_idx-src_idx;
+
+ first = ~fb_shifted_pixels_mask_long(p, (dst_idx + 1) % bits, bswapmask);
+ last = fb_shifted_pixels_mask_long(p, (bits + dst_idx + 1 - n) % bits, bswapmask);
+
+ if (!shift) {
+ // Same alignment for source and dest
+
+ if ((unsigned long)dst_idx+1 >= n) {
+ // Single word
+ if (first)
+ last &= first;
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), last), dst);
+ } else {
+ // Multiple destination words
+
+ // Leading bits
+ if (first) {
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), first), dst);
+ dst--;
+ src--;
+ n -= dst_idx+1;
+ }
+
+ // Main chunk
+ n /= bits;
+ while (n >= 8) {
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ FB_WRITEL(FB_READL(src--), dst--);
+ n -= 8;
+ }
+ while (n--)
+ FB_WRITEL(FB_READL(src--), dst--);
+
+ // Trailing bits
+ if (last != -1UL)
+ FB_WRITEL( comp( FB_READL(src), FB_READL(dst), last), dst);
+ }
+ } else {
+ // Different alignment for source and dest
+ unsigned long d0, d1;
+ int m;
+
+ int const left = shift & (bits-1);
+ int const right = -shift & (bits-1);
+
+ if ((unsigned long)dst_idx+1 >= n) {
+ // Single destination word
+ if (first)
+ last &= first;
+ d0 = FB_READL(src);
+ if (shift < 0) {
+ // Single source word
+ d0 >>= right;
+ } else if (1+(unsigned long)src_idx >= n) {
+ // Single source word
+ d0 <<= left;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src - 1);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+ d0 = d0 << left | d1 >> right;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), last), dst);
+ } else {
+ // Multiple destination words
+ /** We must always remember the last value read, because in case
+ SRC and DST overlap bitwise (e.g. when moving just one pixel in
+ 1bpp), we always collect one full long for DST and that might
+ overlap with the current long from SRC. We store this value in
+ 'd0'. */
+
+ d0 = FB_READL(src--);
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ // Leading bits
+ if (shift < 0) {
+ // Single source word
+ d1 = d0;
+ d0 >>= right;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src--);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+ d0 = d0 << left | d1 >> right;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), first), dst);
+ d0 = d1;
+ dst--;
+ n -= dst_idx+1;
+
+ // Main chunk
+ m = n % bits;
+ n /= bits;
+ while ((n >= 4) && !bswapmask) {
+ d1 = FB_READL(src--);
+ FB_WRITEL(d0 << left | d1 >> right, dst--);
+ d0 = d1;
+ d1 = FB_READL(src--);
+ FB_WRITEL(d0 << left | d1 >> right, dst--);
+ d0 = d1;
+ d1 = FB_READL(src--);
+ FB_WRITEL(d0 << left | d1 >> right, dst--);
+ d0 = d1;
+ d1 = FB_READL(src--);
+ FB_WRITEL(d0 << left | d1 >> right, dst--);
+ d0 = d1;
+ n -= 4;
+ }
+ while (n--) {
+ d1 = FB_READL(src--);
+ d1 = fb_rev_pixels_in_long(d1, bswapmask);
+ d0 = d0 << left | d1 >> right;
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(d0, dst--);
+ d0 = d1;
+ }
+
+ // Trailing bits
+ if (m) {
+ if (m <= bits - left) {
+ // Single source word
+ d0 <<= left;
+ } else {
+ // 2 source words
+ d1 = FB_READL(src);
+ d1 = fb_rev_pixels_in_long(d1,
+ bswapmask);
+ d0 = d0 << left | d1 >> right;
+ }
+ d0 = fb_rev_pixels_in_long(d0, bswapmask);
+ FB_WRITEL(comp(d0, FB_READL(dst), last), dst);
+ }
+ }
+ }
+}
+
+void cfb_copyarea(struct fb_info *p, const struct fb_copyarea *area)
+{
+ u32 dx = area->dx, dy = area->dy, sx = area->sx, sy = area->sy;
+ u32 height = area->height, width = area->width;
+ unsigned long const bits_per_line = p->fix.line_length*8u;
+ unsigned long __iomem *base = NULL;
+ int bits = BITS_PER_LONG, bytes = bits >> 3;
+ unsigned dst_idx = 0, src_idx = 0, rev_copy = 0;
+ u32 bswapmask = fb_compute_bswapmask(p);
+
+ if (p->state != FBINFO_STATE_RUNNING)
+ return;
+
+ /* if the beginning of the target area might overlap with the end of
+ the source area, be have to copy the area reverse. */
+ if ((dy == sy && dx > sx) || (dy > sy)) {
+ dy += height;
+ sy += height;
+ rev_copy = 1;
+ }
+
+ // split the base of the framebuffer into a long-aligned address and the
+ // index of the first bit
+ base = (unsigned long __iomem *)((unsigned long)p->screen_base & ~(bytes-1));
+ dst_idx = src_idx = 8*((unsigned long)p->screen_base & (bytes-1));
+ // add offset of source and target area
+ dst_idx += dy*bits_per_line + dx*p->var.bits_per_pixel;
+ src_idx += sy*bits_per_line + sx*p->var.bits_per_pixel;
+
+ if (p->fbops->fb_sync)
+ p->fbops->fb_sync(p);
+
+ if (rev_copy) {
+ while (height--) {
+ dst_idx -= bits_per_line;
+ src_idx -= bits_per_line;
+ bitcpy_rev(p, base + (dst_idx / bits), dst_idx % bits,
+ base + (src_idx / bits), src_idx % bits, bits,
+ width*p->var.bits_per_pixel, bswapmask);
+ }
+ } else {
+ while (height--) {
+ bitcpy(p, base + (dst_idx / bits), dst_idx % bits,
+ base + (src_idx / bits), src_idx % bits, bits,
+ width*p->var.bits_per_pixel, bswapmask);
+ dst_idx += bits_per_line;
+ src_idx += bits_per_line;
+ }
+ }
+}
+
+EXPORT_SYMBOL(cfb_copyarea);
+
+MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
+MODULE_DESCRIPTION("Generic software accelerated copyarea");
+MODULE_LICENSE("GPL");
+
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-04 01:28:27 +0000