Messages in this thread | | | Date | Wed, 31 Jul 2013 17:21:58 +0200 | From | Sebastian Andrzej Siewior <> | Subject | Re: [PATCH] of: provide of_platform_unpopulate() |
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* Grant Likely | 2013-07-24 15:19:58 [+0100]:
>> Was there more breakage than imx6 and amba devices? Your first version >> had a fallback case for powerpc. Couldn't we do just allow that for more >> than just powerpc? I'd much rather see some work-around within the core >> DT code with a warning to prevent more proliferation than putting this >> into drivers. > >It's tricky stuff. I've not figured out a solution I'm happy with. >Trying to figure out when to apply a work around is hard because the >resource reservation makes assumptions about the memory range layout >that doesn't match the assumptions made by device tree code.
I can't really follow. Do you have a simple at hand?
>One /possible/ option is to not add the resources to the devices at all >when the device is registered and instead resolve them right at bind >time. Jean Christophe proposed doing this already to solve a different >problem; obtaining resources that require other drivers to be probed >first. If the resources are resolved at .probe() time, then the resource >registration problem should also go away. > >The downside to that approach is that it makes each deferred probe more >expensive; potentially a *lot* more expensive depending on how much work >the xlate functions have to do. It would be worth prototyping though to >see how well it works.
So you say defer the io ressources until the device-tree device is actually probed. I don't really understand why that defer part should solve the problem but I would try and see how it goes. Jean-Christophe proposed that only, that means no patches yet, right?
>g.
Sebastian
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