kernel-ark/drivers/video/fb_draw.h
Michal Januszewski bdca0f9b1e fbdev: fix fillrect for 24bpp modes
The software fillrect routines do not work properly when the number of
pixels per machine word is not an integer.  To see that, run the following
command on a fbdev console with a 24bpp video mode, using a
non-accelerated driver such as (u)vesafb:

  reset ; echo -e '\e[41mtest\e[K'

The expected result is 'test' displayed on a line with red background.
Instead of that, 'test' has a red background, but the rest of the line
(rendered using fillrect()) contains a distored colorful pattern.

This patch fixes the problem by correctly computing rotation shifts.  It
has been tested in a 24bpp mode on 32- and 64-bit little-endian machines.

Signed-off-by: Michal Januszewski <spock@gentoo.org>
Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-06 16:36:10 -07:00

184 lines
4.4 KiB
C

#ifndef _FB_DRAW_H
#define _FB_DRAW_H
#include <asm/types.h>
#include <linux/fb.h>
/*
* Compose two values, using a bitmask as decision value
* This is equivalent to (a & mask) | (b & ~mask)
*/
static inline unsigned long
comp(unsigned long a, unsigned long b, unsigned long mask)
{
return ((a ^ b) & mask) ^ b;
}
/*
* Create a pattern with the given pixel's color
*/
#if BITS_PER_LONG == 64
static inline unsigned long
pixel_to_pat( u32 bpp, u32 pixel)
{
switch (bpp) {
case 1:
return 0xfffffffffffffffful*pixel;
case 2:
return 0x5555555555555555ul*pixel;
case 4:
return 0x1111111111111111ul*pixel;
case 8:
return 0x0101010101010101ul*pixel;
case 12:
return 0x1001001001001001ul*pixel;
case 16:
return 0x0001000100010001ul*pixel;
case 24:
return 0x0001000001000001ul*pixel;
case 32:
return 0x0000000100000001ul*pixel;
default:
panic("pixel_to_pat(): unsupported pixelformat\n");
}
}
#else
static inline unsigned long
pixel_to_pat( u32 bpp, u32 pixel)
{
switch (bpp) {
case 1:
return 0xfffffffful*pixel;
case 2:
return 0x55555555ul*pixel;
case 4:
return 0x11111111ul*pixel;
case 8:
return 0x01010101ul*pixel;
case 12:
return 0x01001001ul*pixel;
case 16:
return 0x00010001ul*pixel;
case 24:
return 0x01000001ul*pixel;
case 32:
return 0x00000001ul*pixel;
default:
panic("pixel_to_pat(): unsupported pixelformat\n");
}
}
#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);
return val;
}
static inline u32 fb_shifted_pixels_mask_u32(struct fb_info *p, u32 index,
u32 bswapmask)
{
u32 mask;
if (!bswapmask) {
mask = FB_SHIFT_HIGH(p, ~(u32)0, index);
} else {
mask = 0xff << FB_LEFT_POS(p, 8);
mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
#if defined(__i386__) || defined(__x86_64__)
/* Shift argument is limited to 0 - 31 on x86 based CPU's */
if(index + bswapmask < 32)
#endif
mask |= FB_SHIFT_HIGH(p, ~(u32)0,
(index + bswapmask) & ~(bswapmask));
}
return mask;
}
static inline unsigned long fb_shifted_pixels_mask_long(struct fb_info *p,
u32 index,
u32 bswapmask)
{
unsigned long mask;
if (!bswapmask) {
mask = FB_SHIFT_HIGH(p, ~0UL, index);
} else {
mask = 0xff << FB_LEFT_POS(p, 8);
mask = FB_SHIFT_LOW(p, mask, index & (bswapmask)) & mask;
mask = FB_SHIFT_HIGH(p, mask, index & ~(bswapmask));
#if defined(__i386__) || defined(__x86_64__)
/* Shift argument is limited to 0 - 31 on x86 based CPU's */
if(index + bswapmask < BITS_PER_LONG)
#endif
mask |= FB_SHIFT_HIGH(p, ~0UL,
(index + bswapmask) & ~(bswapmask));
}
return mask;
}
static inline u32 fb_compute_bswapmask(struct fb_info *info)
{
u32 bswapmask = 0;
unsigned bpp = info->var.bits_per_pixel;
if ((bpp < 8) && (info->var.nonstd & FB_NONSTD_REV_PIX_IN_B)) {
/*
* Reversed order of pixel layout in bytes
* works only for 1, 2 and 4 bpp
*/
bswapmask = 7 - bpp + 1;
}
return bswapmask;
}
#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(p, i, b) FB_SHIFT_HIGH((p), ~(u32)0, (i))
#define fb_shifted_pixels_mask_long(p, i, b) FB_SHIFT_HIGH((p), ~0UL, (i))
#define fb_compute_bswapmask(...) 0
#endif /* CONFIG_FB_CFB_REV_PIXELS_IN_BYTE */
#define cpu_to_le_long _cpu_to_le_long(BITS_PER_LONG)
#define _cpu_to_le_long(x) __cpu_to_le_long(x)
#define __cpu_to_le_long(x) cpu_to_le##x
#define le_long_to_cpu _le_long_to_cpu(BITS_PER_LONG)
#define _le_long_to_cpu(x) __le_long_to_cpu(x)
#define __le_long_to_cpu(x) le##x##_to_cpu
static inline unsigned long rolx(unsigned long word, unsigned int shift, unsigned int x)
{
return (word << shift) | (word >> (x - shift));
}
#endif /* FB_DRAW_H */