Re: Problem with ioremap which returns NULL in 2.6 kernel

[Markus Lidel <Markus.Lidel@shadowconnect.com>]

Hello,

Jeff Garzik wrote:
>>>>>My preferred approach would be:  consider that the hardware does not 
>>>>>need the entire 0x8000000-byte area mapped.  Plain and simple.
>>>>>This is a "don't do that" situation, and that renders the other 
>>>>>questions moot :)  You should only be mapping what you need to map.
>>>>Okay, i'll let try it out with only 64MB.
>>>Why do you need 64MB, even?  :)
>>I don't know how much space i need :-D But why does the device set the 
>>size to 128MB then?
> Devices often export things you don't care about, such as direct access
> to internal chip RAM.
> Look through the driver that figure out the maximum value that the
> driver actually _uses_.  There is no need to guess.

Okay, i've looked at it, but i don't think i could simply use less 
space, because (if i understand the I2O spec right :-D) the controller 
returns me a address inside this window, where i could write the I2O 
message. So i ask the controller, where do you want my request, then he 
tells me a address...

If i only ioremap 64MB, and the controller tells me write at 80MB, i'm 
in deep trouble :-D

>> 	size = dev->resource[i].end-dev->resource[i].start+1;	
> You should be using pci_resource_start() and pci_resource_len()
> to obtain this information.

Yep, thanks, but a patch for this is already send :-)

Best regards,



Markus Lidel
------------------------------------------
Markus Lidel (Senior IT Consultant)

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