linux/drivers/video/cfbimgblt.c
Pavel Pisa 779121e9f1 fbdev: Support for byte-reversed framebuffer formats
Allow generic frame-buffer code to correctly write texts and blit images for
1, 2 and 4 bit per pixel frame-buffer organizations when pixels in bytes are
organized to in opposite order than bytes in long type.

Overhead should be reasonable.  If option is not selected, than compiler
should eliminate completely all overhead.

The feature is disabled at compile time if CONFIG_FB_CFB_REV_PIXELS_IN_BYTE is
not set.

[adaplas]
Convert helper functions to macros if feature is not enabled.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Antonino Daplas <adaplas@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:19 -07:00

314 lines
8.2 KiB
C

/*
* Generic BitBLT function for frame buffer with packed pixels of any depth.
*
* Copyright (C) June 1999 James Simmons
*
* 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 function copys a image from system memory to video memory. The
* image can be a bitmap where each 0 represents the background color and
* each 1 represents the foreground color. Great for font handling. It can
* also be a color image. This is determined by image_depth. The color image
* must be laid out exactly in the same format as the framebuffer. Yes I know
* their are cards with hardware that coverts images of various depths to the
* framebuffer depth. But not every card has this. All images must be rounded
* up to the nearest byte. For example a bitmap 12 bits wide must be two
* bytes width.
*
* Tony:
* Incorporate mask tables similar to fbcon-cfb*.c in 2.4 API. This speeds
* up the code significantly.
*
* Code for depths not multiples of BITS_PER_LONG is still kludgy, which is
* still processed a bit at a time.
*
* 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.
*/
#include <linux/module.h>
#include <linux/string.h>
#include <linux/fb.h>
#include <asm/types.h>
#include "fb_draw.h"
#define DEBUG
#ifdef DEBUG
#define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt,__FUNCTION__,## args)
#else
#define DPRINTK(fmt, args...)
#endif
static const u32 cfb_tab8[] = {
#if defined(__BIG_ENDIAN)
0x00000000,0x000000ff,0x0000ff00,0x0000ffff,
0x00ff0000,0x00ff00ff,0x00ffff00,0x00ffffff,
0xff000000,0xff0000ff,0xff00ff00,0xff00ffff,
0xffff0000,0xffff00ff,0xffffff00,0xffffffff
#elif defined(__LITTLE_ENDIAN)
0x00000000,0xff000000,0x00ff0000,0xffff0000,
0x0000ff00,0xff00ff00,0x00ffff00,0xffffff00,
0x000000ff,0xff0000ff,0x00ff00ff,0xffff00ff,
0x0000ffff,0xff00ffff,0x00ffffff,0xffffffff
#else
#error FIXME: No endianness??
#endif
};
static const u32 cfb_tab16[] = {
#if defined(__BIG_ENDIAN)
0x00000000, 0x0000ffff, 0xffff0000, 0xffffffff
#elif defined(__LITTLE_ENDIAN)
0x00000000, 0xffff0000, 0x0000ffff, 0xffffffff
#else
#error FIXME: No endianness??
#endif
};
static const u32 cfb_tab32[] = {
0x00000000, 0xffffffff
};
#define FB_WRITEL fb_writel
#define FB_READL fb_readl
static inline void color_imageblit(const struct fb_image *image,
struct fb_info *p, u8 __iomem *dst1,
u32 start_index,
u32 pitch_index)
{
/* Draw the penguin */
u32 __iomem *dst, *dst2;
u32 color = 0, val, shift;
int i, n, bpp = p->var.bits_per_pixel;
u32 null_bits = 32 - bpp;
u32 *palette = (u32 *) p->pseudo_palette;
const u8 *src = image->data;
u32 bswapmask = fb_compute_bswapmask(p);
dst2 = (u32 __iomem *) dst1;
for (i = image->height; i--; ) {
n = image->width;
dst = (u32 __iomem *) dst1;
shift = 0;
val = 0;
if (start_index) {
u32 start_mask = ~fb_shifted_pixels_mask_u32(start_index, bswapmask);
val = FB_READL(dst) & start_mask;
shift = start_index;
}
while (n--) {
if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
p->fix.visual == FB_VISUAL_DIRECTCOLOR )
color = palette[*src];
else
color = *src;
color <<= FB_LEFT_POS(bpp);
val |= FB_SHIFT_HIGH(color, shift ^ bswapmask);
if (shift >= null_bits) {
FB_WRITEL(val, dst++);
val = (shift == null_bits) ? 0 :
FB_SHIFT_LOW(color, 32 - shift);
}
shift += bpp;
shift &= (32 - 1);
src++;
}
if (shift) {
u32 end_mask = fb_shifted_pixels_mask_u32(shift, bswapmask);
FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
}
dst1 += p->fix.line_length;
if (pitch_index) {
dst2 += p->fix.line_length;
dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
start_index += pitch_index;
start_index &= 32 - 1;
}
}
}
static inline void slow_imageblit(const struct fb_image *image, struct fb_info *p,
u8 __iomem *dst1, u32 fgcolor,
u32 bgcolor,
u32 start_index,
u32 pitch_index)
{
u32 shift, color = 0, bpp = p->var.bits_per_pixel;
u32 __iomem *dst, *dst2;
u32 val, pitch = p->fix.line_length;
u32 null_bits = 32 - bpp;
u32 spitch = (image->width+7)/8;
const u8 *src = image->data, *s;
u32 i, j, l;
u32 bswapmask = fb_compute_bswapmask(p);
dst2 = (u32 __iomem *) dst1;
fgcolor <<= FB_LEFT_POS(bpp);
bgcolor <<= FB_LEFT_POS(bpp);
for (i = image->height; i--; ) {
shift = val = 0;
l = 8;
j = image->width;
dst = (u32 __iomem *) dst1;
s = src;
/* write leading bits */
if (start_index) {
u32 start_mask = ~fb_shifted_pixels_mask_u32(start_index, bswapmask);
val = FB_READL(dst) & start_mask;
shift = start_index;
}
while (j--) {
l--;
color = (*s & (1 << l)) ? fgcolor : bgcolor;
val |= FB_SHIFT_HIGH(color, shift ^ bswapmask);
/* Did the bitshift spill bits to the next long? */
if (shift >= null_bits) {
FB_WRITEL(val, dst++);
val = (shift == null_bits) ? 0 :
FB_SHIFT_LOW(color,32 - shift);
}
shift += bpp;
shift &= (32 - 1);
if (!l) { l = 8; s++; };
}
/* write trailing bits */
if (shift) {
u32 end_mask = fb_shifted_pixels_mask_u32(shift, bswapmask);
FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
}
dst1 += pitch;
src += spitch;
if (pitch_index) {
dst2 += pitch;
dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
start_index += pitch_index;
start_index &= 32 - 1;
}
}
}
/*
* fast_imageblit - optimized monochrome color expansion
*
* Only if: bits_per_pixel == 8, 16, or 32
* image->width is divisible by pixel/dword (ppw);
* fix->line_legth is divisible by 4;
* beginning and end of a scanline is dword aligned
*/
static inline void fast_imageblit(const struct fb_image *image, struct fb_info *p,
u8 __iomem *dst1, u32 fgcolor,
u32 bgcolor)
{
u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel;
u32 ppw = 32/bpp, spitch = (image->width + 7)/8;
u32 bit_mask, end_mask, eorx, shift;
const char *s = image->data, *src;
u32 __iomem *dst;
const u32 *tab = NULL;
int i, j, k;
switch (bpp) {
case 8:
tab = cfb_tab8;
break;
case 16:
tab = cfb_tab16;
break;
case 32:
default:
tab = cfb_tab32;
break;
}
for (i = ppw-1; i--; ) {
fgx <<= bpp;
bgx <<= bpp;
fgx |= fgcolor;
bgx |= bgcolor;
}
bit_mask = (1 << ppw) - 1;
eorx = fgx ^ bgx;
k = image->width/ppw;
for (i = image->height; i--; ) {
dst = (u32 __iomem *) dst1, shift = 8; src = s;
for (j = k; j--; ) {
shift -= ppw;
end_mask = tab[(*src >> shift) & bit_mask];
FB_WRITEL((end_mask & eorx)^bgx, dst++);
if (!shift) { shift = 8; src++; }
}
dst1 += p->fix.line_length;
s += spitch;
}
}
void cfb_imageblit(struct fb_info *p, const struct fb_image *image)
{
u32 fgcolor, bgcolor, start_index, bitstart, pitch_index = 0;
u32 bpl = sizeof(u32), bpp = p->var.bits_per_pixel;
u32 width = image->width;
u32 dx = image->dx, dy = image->dy;
u8 __iomem *dst1;
if (p->state != FBINFO_STATE_RUNNING)
return;
bitstart = (dy * p->fix.line_length * 8) + (dx * bpp);
start_index = bitstart & (32 - 1);
pitch_index = (p->fix.line_length & (bpl - 1)) * 8;
bitstart /= 8;
bitstart &= ~(bpl - 1);
dst1 = p->screen_base + bitstart;
if (p->fbops->fb_sync)
p->fbops->fb_sync(p);
if (image->depth == 1) {
if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
p->fix.visual == FB_VISUAL_DIRECTCOLOR) {
fgcolor = ((u32*)(p->pseudo_palette))[image->fg_color];
bgcolor = ((u32*)(p->pseudo_palette))[image->bg_color];
} else {
fgcolor = image->fg_color;
bgcolor = image->bg_color;
}
if (32 % bpp == 0 && !start_index && !pitch_index &&
((width & (32/bpp-1)) == 0) &&
bpp >= 8 && bpp <= 32)
fast_imageblit(image, p, dst1, fgcolor, bgcolor);
else
slow_imageblit(image, p, dst1, fgcolor, bgcolor,
start_index, pitch_index);
} else
color_imageblit(image, p, dst1, start_index, pitch_index);
}
EXPORT_SYMBOL(cfb_imageblit);
MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
MODULE_DESCRIPTION("Generic software accelerated imaging drawing");
MODULE_LICENSE("GPL");