[BUG] [PATCH 8/10] fbcon: Break up bit_putcs into its component functions

[Knut Petersen <Knut_Petersen@t-online.de>]

The patch is broken, please don´t apply!

If count > maxcnt in bit_putcs(), bit_putcs_(un)aligned() is first 
called to display
maxcnt characters. It returns, and the current value for the source 
pointer s is lost.
Then bit_putcs_(un)aligned() is called again, obviously displaying 
characters from
the start of s and not starting after the last allready displayed character.

Obviously that will only happen for small pixmap buffers, large fonts 
and high
resolutions. For the default pixmap size of 8k, a 16x32 font this bug 
will have
the described results for all xres > 2048, for the same font and a pixmap
size of 4k all xres > 1024.

A small pixmap sizes of 4k gives better overall performance for at least 
the
cyberbade/i1 / Via Samuel 2 combination because of cache effects.

Steps to reproduce:

    - Reduce pixmap size to 4k, compile and reboot or reload framebuffer 
module
    - fbset 1280x1024
    - setfont bitstream_vera_sans_mono_roman.16x30.psf
    - ctrl-alt-f2 ctrl-alt-f1

To Antonino,

    - dont´t pass unused parameters like count, xx and yy to 
bit_putcs_(un)alligned()
    - you do not need to calculate idx if you have calculated and passed 
s_pitch

cu
 knut




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