Re: [linux-fbdev] Matrox and XFree86 4.0.2 update

[Michel Dänzer <daenzer@relog.ch>]

Kostas Gewrgiou wrote:
>
> On Thu, 25 Jan 2001, Geert Uytterhoeven wrote:
>
> > On Thu, 25 Jan 2001, Kostas Gewrgiou wrote:
>
> > > Changing the endian to little is the *right* thing, big-endian mode
> > > doesn't offer us anything beyond problems in matroxfb 8/16 bit accesses
> > > become a nightmare there...
> >
> > 8/16 bit accesses? I assume you're talking about the frame buffer, not
> > about the register accesses?
>
> No i am talking about register accesses, for example
> the mga driver in xfree86 uses
>  #define MGAISBUSY() (INREG8(MGAREG_Status + 2) & 0x01)
> SDL uses
>  #define mga_wait(space)  {                                             \
>         while ( mga_in8(MGAREG_FIFOSTATUS) < space );                   \
>  }
>
> Both will fail under big-endian mode in PPC, the addressing is changed
> so you have to use something like *(addr + (3-addr%4) to get the right
> byte (i hope i got it right, its still early here)

What about adapting the macros then?


Michel


--
Earthling Michel Dänzer (MrCooper)    \   Debian GNU/Linux (powerpc) developer
CS student, Free Software enthusiast   \        XFree86 and DRI project member

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