Re: funny framebuffer fonts on PowerBook with radeonfb

Antonino A. Daplas
2006-03-27T01:20:43Z

Herbert Poetzl wrote:
> Hey Ben!
>
> 2.6.16 and 2.6.15-something show a funny behaviour
> when using the radeonfb driver (for text mode), they
> kind of twist and break the fonts in various places
> some characters or parts seem to be mirrored like
> '[' becoming ']' but not on character boundary but
> more on N pixels, colors seem to be correct for the
> characters, and sometimes the font is perfectly fine
> for larger runs, e.g. I can read the logon prompt
> fine, but everything I type is garbled ...
>
> just for an example, when I type 'echo "Test"' then
> all characters are mirrored and cut off on the right
> side but the locations are as shown above, on enter
> the T is only a few pixels wide, but the est part is
> written perfectly fine ... this is a new behaviour
> and going back to 2.6.13.3 doesn't show this ...
>
> if there is some testing I can do for you, or when
> you need more info, please let me know. here a few
> details for the machine:
>

What font are you using? I presume the dimensions are
not divisible by 8. Can you try this patch?

Tony

diff --git a/drivers/video/cfbimgblt.c b/drivers/video/cfbimgblt.c
index 910e233..8ba6152 100644
--- a/drivers/video/cfbimgblt.c
+++ b/drivers/video/cfbimgblt.c
@@ -169,7 +169,7 @@ static inline void slow_imageblit(const

while (j--) {
l--;
- color = (*s & 1 << (FB_BIT_NR(l))) ? fgcolor : bgcolor;
+ color = (*s & (1 << l)) ? fgcolor : bgcolor;
val |= FB_SHIFT_HIGH(color, shift);

/* Did the bitshift spill bits to the next long? */
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 17fc771..4fe1d2d 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -841,12 +841,10 @@ struct fb_info {
#define FB_LEFT_POS(bpp) (32 - bpp)
#define FB_SHIFT_HIGH(val, bits) ((val) >> (bits))
#define FB_SHIFT_LOW(val, bits) ((val) << (bits))
-#define FB_BIT_NR(b) (7 - (b))
#else
#define FB_LEFT_POS(bpp) (0)
#define FB_SHIFT_HIGH(val, bits) ((val) << (bits))
#define FB_SHIFT_LOW(val, bits) ((val) >> (bits))
-#define FB_BIT_NR(b) (b)
#endif

/*