Re: BBRAM

[Richard Brunelle <rbrunelle@envitech.com>]

Thanks for you hints.

Two more questions:

-How the parameters to SLRAM are passed?
-Is there any provision for pageable memory?


Richard Brunelle


Jörn Engel wrote:

>On Tue, 19 November 2002 13:12:56 -0500, Richard Brunelle wrote:
>  
>
>>Hi, I have a question concerning a BBRAM from ST, the M48Z512A.
>>
>>I'm using the BBRAM mapped at 0xE0000 on a single board computer from 
>>VersaLogic. This BBRAM is pageable through access of a special register 
>>on the single board computer. I want to map the BBRAM as part of the 
>>file system.
>>
>>As I understand MTD is appropriate for this purpose, am I right?
>>
>>If yes, what are the options in the kernel configuration I need to 
>>enable to let the system access the device?
>>
>>My guess is CONFIG_MTD_MTDRAM with the appropriate position set to 
>>0xE0000. In this case, what type of device should I see in /dev/?
>>    
>>
>
>I've been quite happy with the slram driver. The following options
>should be enough:
>CONFIG_MTD
>CONFIG_MTD_CHAR
>CONFIG_MTD_BLOCK
>CONFIG_MTD_SLRAM
>
>In the case of a monolithic kernel, you have to append something like
>this:
>slram=BBRAM,0xE0000,+0x8000
>First parameter is the device name, second is the device start, third
>is the device end or device length (length starts with +).
>
>You have to make sure that the vm doesn't claim the same memory,
>though. Maybe you also need something like mem=8M.
>
>David, there is some Documentation floating around, but not in
>/usr/src/linux/Documentation, where most people would expect it. What
>would I have to do to change that? Commit to cvs? Bitkeeper tree?
>Patch to you/Linus/Marcelo?
>
>Jörn
>
>  
>