RE : Error while accessing physical address

Tks for your answer Marcin. This is a good idea but unfortunately,=20
the result remains the same...
When using "ioremap", do I need need to use inb/oub... family to=20
handle those remapped address??


-------- Message d'origine--------
De: Marcin Dawidowicz [mailto:marcin.dawidowicz@kontron.pl]
Date: jeu. 01/09/2005 16:11
=C0: Garcia J=E9r=E9mie
Objet : Re: Error while accessing physical address
=20
Maybe you could try to change this:

  regHdwAddress =3D (unsigned short *) ioremap((unsigned =

short)address,0x1);
into this:
regHdwAddress =3D (unsigned short *) ioremap((unsigned =
short)address,sizeof=20
(unsigned short));

Cause you are accessing unsigned short register later.... and "unsigned =
short"=20
I assume is 2 bytes long.

Marcin


On Thursday 01 of September 2005 15:44, you wrote:

Hi everybody.

As a kernel newbie, I still encounter basic problems. I read a lot of
things on the memory management, but obviously I didn't understand =

some

things.

I have some kernel source code that only write data to our card =

registers:

void bhWriteCardRegister(unsigned short * address, unsigned short =

data)

{
  unsigned short * regHdwAddress;

  printk("Writing data: %x at address:%x\n",data,address);

  /* Get the virtual address for the physical one */
  regHdwAddress =3D (unsigned short *) ioremap((unsigned =

short)address,0x1);

  printk("ioremap returned : %x\n",regHdwAddress);

  /* write hardware register data value */
  *regHdwAddress =3D data;

  iounmap((void *)regHdwAddress);
}
<<<<<<<<

In a module init I call this function:

#define CARD_PROCESSOR_CTRL_IN_SERVICE    0x8000
#define CARD_PROCESSOR_CTRL_REG_P 0x40000400
bhWriteCardRegister((unsigned short *)(CARD_PROCESSOR_CTRL_REG_P),
(unsigned short)CARD_PROCESSOR_CTRL_IN_SERVICE); <<<<<<<<

When I load this module on our powerPC 405EP based arch, the execution
gives that:

Writing data: 8000 at address:40000400
ioremap returned : c2090400
<<<<<<<<

The problem is that after this write operation, every shell cmd I try =

give

a "segmentation fault". What I did wrong ??

Please help me cause I have to go on fast... (tks boss...)




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