-----Original Message-----
From: Jia Hongtao-B38951
Sent: Friday, September 21, 2012 11:14 AM
To: Kumar Gala
Cc: linuxppc-dev@lists.ozlabs.org; Li Yang-R58472; Wood Scott-B07421
Subject: RE: [PATCH][V4] powerpc/fsl-pci: Add pci inbound/outbound PM
support
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-----Original Message-----
From: Kumar Gala [mailto:galak@kernel.crashing.org]
Sent: Wednesday, September 19, 2012 11:49 PM
To: Jia Hongtao-B38951
Cc: linuxppc-dev@lists.ozlabs.org; Li Yang-R58472; Wood Scott-B07421
Subject: Re: [PATCH][V4] powerpc/fsl-pci: Add pci inbound/outbound PM
support

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On Sep 17, 2012, at 9:10 PM, Jia Hongtao wrote:

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Power supply for PCI inbound/outbound window registers is off
when system go to deep-sleep state. We save the values of
registers

before

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suspend and restore to registers after resume.

Signed-off-by: Jiang Yutang <redacted>
Signed-off-by: Jia Hongtao <redacted>
Signed-off-by: Li Yang <redacted>
---
Changes for V4:
We just rebase the patch upon following patch:
powerpc/fsl-pci: Unify pci/pcie initialization code

arch/powerpc/include/asm/pci-bridge.h |    2 +-
arch/powerpc/sysdev/fsl_pci.c         |  121

+++++++++++++++++++++++++++++++++

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2 files changed, 122 insertions(+), 1 deletions(-)

Did you ever compare this to just re-parsing device tree method?

- k

I tested the re-parsing way by using setup_pci_atmu() when resume.
And I found out that re-parsing will *change* outbound IO
translation address regitster.

It seems that in the first bootup, after setup_atmu()
pcibios_setup_phb_resources() may update hose->io_resource, but
atmu is not updated according to the new hose->io_resource value.
In resume from sleep setup_atmu() will reset atmu according to the
new hose->io_resource value. So the setup_atmu() will cause
different result on outbound IO register between first bootup and
resume from sleep.

So... There's a possibility that in the first bootup atmu is not
setup properly.

[Are you seeing this happen in your testing?  If so its a bug we
need

to look at fixing.]

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Yes, I see this in my testing.
Also PCIe ethernet card works well after resuming from sleep in both

save/restore

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and re-parsing way. (Maybe PCIe ethernet card don't need outbound IO

resource)

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So, I guess the result of re-parsing (actually it's re-setup) is
right

and ATMU is not setup

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properly at the first bootup.

Are you seeing the following message - "PCI: I/O resource not set for
host bridge" ?

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No.
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Trying to understand why you'd hit the reassignment of io_resource.

- k

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I did some investigations and the conclusion is:
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io_resource.flags & IORESOURCE_IO are both positive but io_resource.start
is 0 before pcibios_setup_phb_io_space() is done.
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The sequence of related process listed below:
fsl_add_bridge() -> setup_pci_atmu()
pcibios_init() -> pcibios_scan_phb() -> pcibios_setup_phb_io_space()
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Because fsl_add_bridge() must be finished before pcibios_init() so ATMU
is set when io_resource.start is 0. That means outbound IO regs are not
set.
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If system re-setup ATMU the io_resource.start has already updated so
outbound IO regs are set.
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My question is:
Is there any problem if outbound IO regs are not set in first bootup?

Please also provide the IO resource address range before and after the pci =
scan.  Then we can evaluate if the range is needed to be mapped via ATMU.

Leo