Re: [RFC:PATCH dtc-1.3.0] dtc: Add --strip-disabled option to dtc.

[Srinivas KANDAGATLA <srinivas.kandagatla-qxv4g6HH51o@public.gmane.org>]

On 17/08/12 16:36, Timur Tabi wrote:
> Srinivas KANDAGATLA wrote:
>> If you know in advance that device on that SOC is broken, then I guess
>> "Fail"/"Failed" can be used in status property.
>>
>> One user of this flag in kernel device trees is
>> ./arch/powerpc/boot/dts/mpc8313erdb.dts
> 	/* Remove this (or change to "okay") if you have
> 	 * a REVA3 or later board, if you apply one of the
> 	 * workarounds listed in section 8.5 of the board
> 	 * manual, or if you are adapting this device tree
> 	 * to a different board.
> 	 */
> 	status = "fail";
>
> I'm not sure this is the right way to do it. 
I agree, the way fail status is used is pretty much redundant to what
"disabled" is used for.
I think the device trees files should have status as "okay" or "ok" or
"disabled" or skip status property totally.

>  Normally, the boot loader
> should be able to detect the board revision, and it should dynamically set
> the 'status'.  We have other devices that fail if a work-around is not
> applied, and we don't use this approach.
>
> But assuming that this really is the best approach, then it would make
> sense for --strip-disabled to leave this node in the dtb, because
> otherwise there would be no way to re-enable it.
--strip-disabled should still get rid for nodes marked as failed
as-well, because fail means something serious and un-recoverable.

I think bootloader should not even consider nodes with status as fail, as the device is unlikely to become operational without repair.

>