________________________________________ From: Kumar Gala [ga...@kernel.crashing.org] Sent: Wednesday, September 19, 2012 10:27 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
On Sep 19, 2012, at 2:10 AM, Jia Hongtao-B38951 wrote: > > >> -----Original Message----- >> From: Kumar Gala [mailto:ga...@kernel.crashing.org] >> Sent: Tuesday, September 18, 2012 1:04 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 >> >> >> On Sep 17, 2012, at 9:10 PM, Jia Hongtao wrote: >> >>> Power supply for PCI inbound/outbound window registers is off when >>> system go to deep-sleep state. We save the values of registers before >>> suspend and restore to registers after resume. >>> >>> Signed-off-by: Jiang Yutang <b14...@freescale.com> >>> Signed-off-by: Jia Hongtao <b38...@freescale.com> >>> Signed-off-by: Li Yang <le...@freescale.com> >>> --- >>> 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 >> +++++++++++++++++++++++++++++++++ >>> 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.] Yes, I see this in my testing. Also PCIe ethernet card works well after resuming from sleep in both save/restore and re-parsing way. (Maybe PCIe ethernet card don't need outbound IO resource) So, I guess the result of re-parsing (actually it's re-setup) is right and ATMU is not setup properly at the first bootup. > > Anyway, if setup_pci_atmu() at resume is functionally right then re-parsing > is a good way for PM. I also test the latency of re-parsing and save/restore, > both way are acceptable. > > > - Hongtao. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
