Re: [PATCH V3 1/5] powerpc/fsl-pci: Unify pci/pcie initialization code

On Jul 30, 2012, at 3:26 AM, Jia Hongtao-B38951 wrote:

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-----Original Message-----
From: Kumar Gala [mailto:galak@kernel.crashing.org]
Sent: Saturday, July 28, 2012 5:17 AM
To: Wood Scott-B07421
Cc: Jia Hongtao-B38951; linuxppc-dev@lists.ozlabs.org; Wood =

Scott-B07421;

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Li Yang-R58472
Subject: Re: [PATCH V3 1/5] powerpc/fsl-pci: Unify pci/pcie
initialization code
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On Jul 27, 2012, at 3:24 PM, Scott Wood wrote:
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On 07/27/2012 05:10 AM, Jia Hongtao-B38951 wrote:

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Hi kumar,
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I know "duplicate code from pci_process_bridge_OF_ranges()" is
hard to accept but "refactor the code to have a shared function"
is knotty. Actually this is the reason I didn't do the refactor.

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Maybe we should keep doing the init early?  We could still have a
platform device for the PM stuff, but some init would be done before

probe.

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Another possibility is to try to handle swiotlb init later -- =

possibly

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by reserving memory for it if the platform indicates it's a =

possibility

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that it will be needed, then freeing the memory if it's not needed.
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-Scott

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I think the first option seems reasonable.  Can we leave =

fsl_pci_init()

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as we now have it and just have the platform driver deal with PM =

restore

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via calling setup_pci_atmu() [probably need to update setup_pci_atmu =

to

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handle restore case, but seems like minor changes]
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- k
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I think the second option is better if it's hard to decouple swiotlb
determination from pci init. I believe the better architecture that
PCI init in probe function of platform driver will bring us =

considerable

advantage. I really like to keep the completion of pci controller
platform driver not only for PM support but also for pci init.
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-Hongtao.=20
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Shifting of swiotlb init has a lot more issues.  Why do we need to do =
the PCI init in probe?

- k=