Flat device tree definitions for FLASH and MTD partitioning
Sergei Shtylyov
sshtylyov at ru.mvista.com
Thu Apr 26 00:34:47 EST 2007
Hello.
Wolfgang Grandegger wrote:
>>>>>> are there already some thought or even example code on how to
>>>>>> define Flash memory and MTD partitions in the DTS. This would
>>>>>> avoid the ackward MTD partitioning via static structure or boot
>>>>>> line argument and could be done in a generic way.
>>>>> See Documentation/powerpc/booting-without-of.txt and
>>>>> drivers/mtd/physmap_of.c for what's been already done.
>>>> I meant drivers/mtd/maps/physmap_of.c
>>> I had a closer look to this driver. Unfortunately, it can not handle
>>> yet multiple FLASH banks. This could be achieved with an additional
>>> property "bank_count". What do you think?
Please use hyphen, not underscore in property names ("device_type" seems an only exception from this rule).
>> I'm not sure what banks you're talking about -- note that this driver
>> is equivalen in functionality to the plain 'physmap' driver and
>> there's inherited "bank-width" property that handles flash banking.
> Yes, I know. Nevertheless the driver cannot handle flash regions
> composed of more than on FLASH bank because we need to probe every bank.
> Search for "BANK" in drivers/mtd/maps" to understand what I mean.
Hm, from what I could see, those banks are separate maps registered to MTD subsys separately.
What's the point of adding a count property when we simply can define multiple "rom" devices?
> Wolfgang.
MBR, Sergei
More information about the Linuxppc-embedded
mailing list