Re: [RM9200] Using data bus and address bus through Linux Kernel

[Frederic Kwiatkowski <katolecho@xxxxxxxxx>]

Hello Ole,

2009/5/4 Ole Loots <ole@xxxxxxxxxxxxx>

> Hello Frederic,
>
>> The main problem is that during the init step, it seems that an access to
>> flash memory is done (input/output error in shell, JFFS2 notice in debug).
>>
>>
> As far as I remember, CS7 memory region works well for me.


Ok, so i'll try on CS7 as soon as possible to compare with CS4 and watch if
I've got the same input/output error

 So I have several question about all of this.
>> - Is this possible to access to data and address bus such as I/O's even if
>> SDRAM, Flash memory and so on are connected?
>>
>>
> Yes, I'm doing that, it works fine with CS7 memory region.
>
>> - If data bus can be used through writeb, is there any possibilty for
>> address bus to be accessed in a similar way?
>>
>>
> When you use writeb on the CS regions - than that involves the address bus.
> writeb in the CS7 region puts the adress to the adress bus...
> Furthermore there are some address bus pins that are multiplexed with the
> GPIO's, a21-a23, I believe.

So writing to 0x703FF FFFF will put the address bus to 0x003F FFFF (if we
don't care about multiplexing with the GPIO)?

Thanks for your help

Regards,
Frederic
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