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* Re: IMAP_ADDR is virtual or physical address?
  2006-02-15 21:41 IMAP_ADDR is virtual or physical address? dibacco
@ 2006-02-15 21:36 ` Kumar Gala
  0 siblings, 0 replies; 2+ messages in thread
From: Kumar Gala @ 2006-02-15 21:36 UTC (permalink / raw)
  To: dibacco@inwind.it; +Cc: linuxppc-embedded

On Wed, 15 Feb 2006, dibacco@inwind.it wrote:

> I'm wondering if IMAP_ADDR is a virtual address or a physical one. Normally I see things like this in drivers:
> 
> static volatile immap_t *immr = (immap_t *) IMAP_ADDR;
> 
> It seems therefore a virtual address.

IMAP_ADDR tends to be a physical address, however its mapped 1:1 in the 
kernel via io_block_mapping() on a number of systems to get the 1:1 
mapping.

This is somewhat frowned upon, and drivers should really do their own 
ioremap() with a physical address for IMAP_ADDR.

> 
> But I can see the same also in some u-boot code where I imagine we are accessing physical addresses.
> 
> Clear my doubt please!!

In u-boot everything is mapped 1:1 so there is no difference between virt 
and phys addrs.

- kumar

^ permalink raw reply	[flat|nested] 2+ messages in thread

* IMAP_ADDR is virtual or physical address?
@ 2006-02-15 21:41 dibacco
  2006-02-15 21:36 ` Kumar Gala
  0 siblings, 1 reply; 2+ messages in thread
From: dibacco @ 2006-02-15 21:41 UTC (permalink / raw)
  To: linuxppc-embedded

I'm wondering if IMAP_ADDR is a virtual address or a physical one. Normal=
ly I see things like this in drivers:

static volatile immap_t *immr =3D (immap_t *) IMAP_ADDR;

It seems therefore a virtual address.

But I can see the same also in some u-boot code where I imagine we are ac=
cessing physical addresses.

Clear my doubt please!!

Bye,

^ permalink raw reply	[flat|nested] 2+ messages in thread

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2006-02-15 21:41 IMAP_ADDR is virtual or physical address? dibacco
2006-02-15 21:36 ` Kumar Gala

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