On 08/08/2012 10:48 PM, Jia Hongtao-B38951 wrote: > > >> -----Original Message----- >> From: Wood Scott-B07421 >> Sent: Thursday, August 09, 2012 12:02 AM >> To: Jia Hongtao-B38951 >> Cc: Wood Scott-B07421; linuxppc-dev@lists.ozlabs.org; >> ga...@kernel.crashing.org; Li Yang-R58472 >> Subject: Re: [PATCH V5 3/3] powerpc/fsl-pci: Unify pci/pcie >> initialization code >> >> On 08/08/2012 04:39 AM, Jia Hongtao-B38951 wrote: >>> >>> >>>> -----Original Message----- >>>> From: Wood Scott-B07421 >>>> Sent: Tuesday, August 07, 2012 11:29 PM >>>> To: Jia Hongtao-B38951 >>>> Cc: Wood Scott-B07421; linuxppc-dev@lists.ozlabs.org; >>>> ga...@kernel.crashing.org; Li Yang-R58472 >>>> Subject: Re: [PATCH V5 3/3] powerpc/fsl-pci: Unify pci/pcie >>>> initialization code >>>> >>>> On 08/07/2012 03:09 AM, Jia Hongtao-B38951 wrote: >>>>> I am really not sure that all boards need primary bus. Could you >>>>> give me the link of discussion about primary that you mentioned? >>>> >>>> https://lists.ozlabs.org/pipermail/linuxppc-dev/2012-June/098586.html >>>> >>>> -Scott >>> >>> >>> It seems in qemu isa_io_base must be non-zero. >> >> In all cases. It just shows up worse under QEMU because of a different >> issue. >> >>> If there is no isa bridge should isa_io_base be non-zero for other >> boards? >> >> Yes, until the bugs are fixed. >> >>> If not maybe we should fix qemu bug. >> >> If you want to try to make QEMU accept I/O BARs with address zero, go >> ahead, but you don't get to assume that someone else will do it, we still >> need to be compatible with older QEMUs (this bug is not so severe that >> compatibility is unreasonable), and it still doesn't address the fact >> that things are not functioning as designed. IIRC there are some real >> hardware PCI cards that don't like getting an address of zero either. >> >>> Or "quick fix" in the link is a workaround. >> >> I think that "quick fix" may have problems if there is a primary bus but >> it's not the first one detected. In any case, any fix or workaround has >> to happen before you make changes that rely on it. >> >> -Scott > > If there is no primary assigned and accidently the primary is not the > first one this "quick fix" may have problem. But this -accident- only happened > in ge_imp3a board if I didn't miss other boards.
How is it an accident? It's a perfectly legitimate situation. > So if there is no primary assigned but the primary is the first bus detected > this "quick fix" is right. That means the "quick fix" is the equivalent > substitution for "arbitrarily designate one as primary". It's not equivalent because I didn't try to convert the ge_imp3a board, and if I did I would have added special code to the ge_imp3a board to set the fsl_pci_primary before calling fsl_pci_init(). -Scott _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
