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List:       linux-arm-kernel
Subject:    Re: q:cf/pcmcia
From:       "Jean-Philippe Francois" <jp.francois () cynove ! com>
Date:       2004-06-23 8:06:26
Message-ID: 200406231006260531.0047B03B () smtp ! wanadoo ! fr
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On 23/06/2004 at 07:39 Ian Campbell wrote:

>I'm not sure why you are starting a new thread instead of continuing the
>existing thread on the subject -- it makes it quite hard to follow.
>
>On Wed, 2004-06-23 at 01:41, zxk wrote:
>> but,I want my cf card to run at memory work mode because 
>> AT91RM9200 can only work memory mode.
>
>I think you are confusing the access method for the CF card (I/O vs.
>memory mapped) with the function of the CF card ('memory', 'fixed disk',
>'network'). The two are not necessarily related. 
>
>I think you should compile IDE + IDE CS support, etc, into your kernel
>and load them up -- I think you will be pleasently surprised.
>
>All CF (and PCMCIA) cards can be accessed using either (or both) memory
>mapped or I/O mapped accesses. However, on ARM platforms there is no
>concept of an I/O address space like there is on i386 so the CF cards
>I/O address space is actually memory mapped to some memory region. The
>fact that your platform 'can only work in memory mode' doesn't matter
>since there will be a memory address region which translates into i/o
>accesses as far as the CF card is concerned.
>
Moreover, the at91rm9200 external interface include internal logic
to handle memory and io access.
What do you think the CFIOR_ and CFIOW_ are used for ?

CF card works perfectly fine in io/mode, except there is no interrupt.

JP Francois



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