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Commit 15afdd43 authored by Pavel Pisa's avatar Pavel Pisa Committed by Linus Torvalds
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fbdev: copyarea function taught to fully support swapped pixel order in byte 

This correct case, when source and destination X coordinates difference is n
multiple of pixels in byte.  This is probably rare case, but this case should
supported for completeness.

Reorganization of FB_READL and FB_WRITEL calls results in code size decrease
for normal build without swapping support and size with support enabled is
reasonable too.

[adaplas]
Add missing fb_rev_pixels_in_long() prototype.
Signed-off-by: default avatarPavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: default avatarAntonino Daplas <adaplas@gmail.com>
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c3ca34f9
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Inline Side-by-side
Showing with 87 additions and 25 deletions
drivers/video/cfbcopyarea.c
View file @ 15afdd43
......@@ -94,29 +94,34 @@ bitcpy(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem *src
FB_WRITEL( comp( FB_READL(src), FB_READL(dst), last), dst);
}
} else {
/* Different alignment for source and dest */
unsigned long d0, d1;
int m;
// Different alignment for source and dest
right = shift & (bits - 1);
left = -shift & (bits - 1);
bswapmask &= shift;
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
FB_WRITEL( comp( FB_READL(src) >> right, FB_READL(dst), first), dst);
d0 >>= right;
} else if (src_idx+n <= bits) {
// Single source word
FB_WRITEL( comp(FB_READL(src) << left, FB_READL(dst), first), dst);
d0 <<= left;;
} else {
// 2 source words
d0 = FB_READL(src++);
d1 = FB_READL(src);
FB_WRITEL( comp(d0<<left | d1>>right, FB_READL(dst), first), dst);
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), first), dst);
} else {
// Multiple destination words
/** We must always remember the last value read, because in case
......@@ -125,25 +130,31 @@ bitcpy(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem *src
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
FB_WRITEL( comp(d0 >> right, FB_READL(dst), first), dst);
d1 = d0;
d0 >>= right;
dst++;
n -= bits - dst_idx;
} else {
// 2 source words
d1 = FB_READL(src++);
FB_WRITEL( comp(d0<<left | d1>>right, FB_READL(dst), first), dst);
d0 = d1;
d1 = fb_rev_pixels_in_long(d1, bswapmask);
d0 = d0<<left | d1>>right;
dst++;
n -= bits - dst_idx;
}
d0 = fb_rev_pixels_in_long(d0, bswapmask);
FB_WRITEL(comp(d0, FB_READL(dst), first), dst);
d0 = d1;
// Main chunk
m = n % bits;
n /= bits;
while (n >= 4) {
while ((n >= 4) && !bswapmask) {
d1 = FB_READL(src++);
FB_WRITEL(d0 << left | d1 >> right, dst++);
d0 = d1;
......@@ -160,7 +171,10 @@ bitcpy(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem *src
}
while (n--) {
d1 = FB_READL(src++);
FB_WRITEL(d0 << left | d1 >> right, dst++);
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;
}
......@@ -168,12 +182,16 @@ bitcpy(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem *src
if (last) {
if (m <= right) {
// Single source word
FB_WRITEL( comp(d0 << left, FB_READL(dst), last), dst);
d0 <<= left;
} else {
// 2 source words
d1 = FB_READL(src);
FB_WRITEL( comp(d0<<left | d1>>right, FB_READL(dst), last), dst);
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);
}
}
}
......@@ -247,24 +265,32 @@ bitcpy_rev(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem
}
} 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);
bswapmask &= shift;
if ((unsigned long)dst_idx+1 >= n) {
// Single destination word
if (last)
first &= last;
d0 = FB_READL(src);
if (shift < 0) {
// Single source word
FB_WRITEL( comp( FB_READL(src)<<left, FB_READL(dst), first), dst);
d0 <<= left;
} else if (1+(unsigned long)src_idx >= n) {
// Single source word
FB_WRITEL( comp( FB_READL(src)>>right, FB_READL(dst), first), dst);
d0 >>= right;
} else {
// 2 source words
FB_WRITEL( comp( (FB_READL(src)>>right | FB_READL(src-1)<<left), FB_READL(dst), first), dst);
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
......@@ -272,27 +298,30 @@ bitcpy_rev(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem
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'. */
unsigned long d0, d1;
int m;
d0 = FB_READL(src--);
d0 = fb_rev_pixels_in_long(d0, bswapmask);
// Leading bits
if (shift < 0) {
// Single source word
FB_WRITEL( comp( (d0 << left), FB_READL(dst), first), dst);
d1 = d0;
d0 <<= left;
} else {
// 2 source words
d1 = FB_READL(src--);
FB_WRITEL( comp( (d0>>right | d1<<left), FB_READL(dst), first), dst);
d0 = d1;
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);
d0 = d1;
dst--;
n -= dst_idx+1;
// Main chunk
m = n % bits;
n /= bits;
while (n >= 4) {
while ((n >= 4) && !bswapmask) {
d1 = FB_READL(src--);
FB_WRITEL(d0 >> right | d1 << left, dst--);
d0 = d1;
......@@ -309,7 +338,10 @@ bitcpy_rev(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem
}
while (n--) {
d1 = FB_READL(src--);
FB_WRITEL(d0 >> right | d1 << left, dst--);
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;
}
......@@ -317,12 +349,16 @@ bitcpy_rev(unsigned long __iomem *dst, int dst_idx, const unsigned long __iomem
if (last) {
if (m <= left) {
// Single source word
FB_WRITEL( comp(d0 >> right, FB_READL(dst), last), dst);
d0 >>= right;
} else {
// 2 source words
d1 = FB_READL(src);
FB_WRITEL( comp(d0>>right | d1<<left, FB_READL(dst), last), dst);
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);
}
}
}
......
drivers/video/fb_draw.h
View file @ 15afdd43
......@@ -72,6 +72,26 @@ pixel_to_pat( u32 bpp, u32 pixel)
#endif
#ifdef CONFIG_FB_CFB_REV_PIXELS_IN_BYTE
#if BITS_PER_LONG == 64
#define REV_PIXELS_MASK1 0x5555555555555555ul
#define REV_PIXELS_MASK2 0x3333333333333333ul
#define REV_PIXELS_MASK4 0x0f0f0f0f0f0f0f0ful
#else
#define REV_PIXELS_MASK1 0x55555555ul
#define REV_PIXELS_MASK2 0x33333333ul
#define REV_PIXELS_MASK4 0x0f0f0f0ful
#endif
static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
u32 bswapmask)
{
if (bswapmask & 1)
val = comp(val >> 1, val << 1, REV_PIXELS_MASK1);
if (bswapmask & 2)
val = comp(val >> 2, val << 2, REV_PIXELS_MASK2);
if (bswapmask & 3)
val = comp(val >> 4, val << 4, REV_PIXELS_MASK4);
}
static inline u32 fb_shifted_pixels_mask_u32(u32 index, u32 bswapmask)
{
......@@ -131,6 +151,12 @@ static inline u32 fb_compute_bswapmask(struct fb_info *info)
#else /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
static inline unsigned long fb_rev_pixels_in_long(unsigned long val,
u32 bswapmask)
{
return val;
}
#define fb_shifted_pixels_mask_u32(i, b) FB_SHIFT_HIGH(~(u32)0, (i))
#define fb_shifted_pixels_mask_long(i, b) FB_SHIFT_HIGH(~0UL, (i))
#define fb_compute_bswapmask(...) 0
......
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