Re: still no accelerated X ($#!$*)

Re: still no accelerated X ($#!$*)

[Moritz Thomas]

Finally I got it!

The problem was in the Xpmac code. If I remember correctly, this error
was some time ago in the kernel's "atyfb.c" as well. Probably this is also
fixed in current release of Xpmac

The following functions in "regmach.h":
#if defined (__powerpc__)
extern pointer mach64MemReg;

static inline void regw(volatile unsigned long regindex, unsigned long regdata)
{
  register unsigned long base_addr = (unsigned long)mach64MemReg;

  asm("stwbrx %0,%1,%2": : "r"(regdata), "r"(regindex), "r"(base_addr));
}

static inline unsigned long regr(volatile unsigned long regindex)
{
  register unsigned long base_addr = (unsigned long)mach64MemReg, val;

  asm("lwbrx %0,%1,%2": "=r"(val):"r"(regindex), "r"(base_addr));
  return(val);
}
#endif

need to be replaced by:
#if defined (__powerpc__)
extern pointer mach64MemReg;

static inline void regw(volatile unsigned long regindex, unsigned long regdata)
{
  register unsigned long base_addr = (unsigned long)mach64MemReg;

  asm("stwbrx %0,%1,%2": : "r"(regdata), "b"(regindex), "r"(base_addr));
}

static inline unsigned long regr(volatile unsigned long regindex)
{
  register unsigned long base_addr = (unsigned long)mach64MemReg, val;

  asm("lwbrx %0,%1,%2": "=r"(val):"b"(regindex), "r"(base_addr));
  return(val);
}
#endif

Don't know if this is correct (no clue about ppc assembly), but it works...

mo


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Re: still no accelerated X ($#!$*)

[David Edelsohn]

	Why does each application/library define its own, incorrect
definition of byte-reversed instructions?  Doesn't some Linux/PPC header
file define this once in a awy that could be imported by others?

	One cannot use "r" as a constraint for a base address, that is
what the GCC PowerPC port defines "b" for.  The load/store instruction
patterns in the GCC PowerPC machine description file use a different
constraint letter for the base address, and anyone writing inlined
assembly -- especially loads and stores -- should browse the GCC machine
description.

David


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Re: still no accelerated X ($#!$*)

[Kevin Hendricks]

Hi,

Thanks for your reply.

> Why does each application/library define its own, incorrect
> definition of byte-reversed instructions?  Doesn't some Linux/PPC header
> file define this once in a awy that could be imported by others?

I could not find one.  I will look again.

> 	One cannot use "r" as a constraint for a base address, that is
> what the GCC PowerPC port defines "b" for.  The load/store instruction
> patterns in the GCC PowerPC machine description file use a different
> constraint letter for the base address, and anyone writing inlined
> assembly -- especially loads and stores -- should browse the GCC machine
> description.

Thanks I will as soon as I find it ;-).  But the assembler generated was exactly
the same in my simple test case.  Is this just luck?

Thanks,

Kevin

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Re: still no accelerated X ($#!$*)

[Geert Uytterhoeven]

On Thu, 20 Jan 2000, Kevin Hendricks wrote:
> > 	One cannot use "r" as a constraint for a base address, that is
> > what the GCC PowerPC port defines "b" for.  The load/store instruction
> > patterns in the GCC PowerPC machine description file use a different
> > constraint letter for the base address, and anyone writing inlined
> > assembly -- especially loads and stores -- should browse the GCC machine
> > description.
>
> Thanks I will as soon as I find it ;-).  But the assembler generated was exactly
> the same in my simple test case.  Is this just luck?

Yes it is.

Gr{oetje,eeting}s,
--
Geert Uytterhoeven -- Linux/{m68k~Amiga,PPC~CHRP} -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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Re: still no accelerated X ($#!$*)

[Ruben Malchow]

>>Then boot your kernel with BootX  with the "No Video Driver" box *checked*.
>>

i was having some trouble with xserver acceleration too, but a look at this 


http://www.members.home.net/njolly/xfree86/kernel_arg_table.html

instead of relying on the kernel params provided by BootX did the trick for me
on a b&w g3 

.rm


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