some more doubts regarding memory access from user/kernel space

some more doubts regarding memory access from user/kernel space

[Vijay Padiyar]

Hi

Some more doubts about the same thing.

As I am aware, the MPC8260 does not have a separate I/O address space. So,
with reference to my earlier mail, when do we need to use ioremap() and when
do we need to use request_mem_region()? Or do we need to use both in a
particular sequence?

Also, if I just do an ioremap(), can I directly access those remapped
addresses with inb()/outb() or writeb()/readb()? Or is something more to be
done prior to accessing it?

Regards

Vijay Padiyar

http://www.vijaypadiyar.eu.tf

AW: some more doubts regarding memory access from user/kernel space

[Achim Machura]

Hello Vijay,

> -----Ursprüngliche Nachricht-----
> Von: linuxppc-embedded-bounces@ozlabs.org
> [mailto:linuxppc-embedded-bounces@ozlabs.org]Im Auftrag von Vijay
> Padiyar

> with reference to my earlier mail, when do we need to use
> ioremap() and when
> do we need to use request_mem_region()? Or do we need to use both in a
> particular sequence?

I think first you have to progamm the chip select of your cpld correctly.
(see the mail from Mark)
You can do this in your module_init funktion.

Now you call request_mem_region to mark this memory used.
Now can mapp the virtual adress to your process by calling ioremap().

Regards

Achim