> -----Original Message----- > From: Jia Hongtao-B38951 > Sent: Tuesday, April 10, 2012 5:17 PM > To: Kumar Gala > Cc: devicetree-disc...@lists.ozlabs.org; linuxppc-dev@lists.ozlabs.org; > Li Yang-R58472; Jia Hongtao-B38951 > Subject: RE: [RFC] powerpc/fsl-pci: Document the "fsl,has-isa" property > for Freescale PCI > > > > -----Original Message----- > > From: linuxppc-dev-bounces+b38951=freescale....@lists.ozlabs.org > > [mailto:linuxppc-dev-bounces+b38951=freescale....@lists.ozlabs.org] On > > Behalf Of Jia Hongtao-B38951 > > Sent: Friday, April 06, 2012 11:05 AM > > To: Kumar Gala > > Cc: devicetree-disc...@lists.ozlabs.org; linuxppc-dev@lists.ozlabs.org; > > Li Yang-R58472 > > Subject: RE: [RFC] powerpc/fsl-pci: Document the "fsl,has-isa" property > > for Freescale PCI > > > > > > > -----Original Message----- > > > From: Kumar Gala [mailto:ga...@kernel.crashing.org] > > > Sent: Wednesday, April 04, 2012 9:09 PM > > > To: Jia Hongtao-B38951 > > > Cc: linuxppc-dev@lists.ozlabs.org; Li Yang-R58472; devicetree- > > > disc...@lists.ozlabs.org > > > Subject: Re: [RFC] powerpc/fsl-pci: Document the "fsl,has-isa" > property > > > for Freescale PCI > > > > > > > > > On Apr 1, 2012, at 1:56 AM, Jia Hongtao wrote: > > > > > > > If PCI is primary bus we should set isa_io/mem_base when parsing > PCI > > > bridge > > > > resources from device tree. The previous way to check the primary > bus > > > based > > > > on a hard-coded address named primary_phb_addr. Now we add a > property > > > named > > > > "fsl,has-isa" into device tree. In kernel we use this property to > > find > > > out > > > > the bus is primary or not. This way is more flexible. > > > > > > > > Signed-off-by: Jia Hongtao <b38...@freescale.com> > > > > Signed-off-by: Li Yang <le...@freescale.com> > > > > --- > > > > .../devicetree/bindings/powerpc/fsl/pci.txt | 36 > > > ++++++++++++++++++++ > > > > 1 files changed, 36 insertions(+), 0 deletions(-) > > > > create mode 100644 > > > Documentation/devicetree/bindings/powerpc/fsl/pci.txt > > > > > > This isn't freescale specific, its linux specific. If anything the > > > property should be linux,has-isa. > > > > > > But in general I dont think this is a good idea. In truth one could > > > search the device tree for: > > > > > > device_type = "isa"; > > > > > > to try and set this dynamically. > > > > > > - k > > > > > > > Yes, it's not Freescale specific, but it's only used by Freescale now > in > > the kernel. This is why I named the property as "fsl,has-isa". > > > > To indicate PCI bus is primary we have three ways to go and we now like > > the 2nd solution: > > > > 1. As this patch said, we add a property to device tree manually. > > > > 2. Set this property dynamically in uboot when scanning PCI bridge. > > Actually we have already done this. The problem is users should update > > uboot and kernel together or it's not work. To support old uboot we > > decide > > to add this property into device tree too temporarily. We will remove > it > > from device tree at an appropriate future. > > > > 3. Just as you said we could search the device tree by device_type = > > "isa". > > There are two problems here: > > * There is no OF API for searching just in PCI node now. That means > > we can't easily find whether there is "isa" bridge or not under > > this PCI controller while scanning it. > > * Boards MPC8541CDS and MPC8555CDS has no "isa" node in device tree > > but has ISA bridge under PCI controller. > > > > - Jia Hongtao > > > > Hi Kumar, > > I agree with the name change from "fsl,has-isa" to "linux,has-isa". > If this is ok I will update this patch and send the patches based on this > new property. > > Also, I have a question about "isa" node in dts. Is this node being used > by kernel? If not we can remove it from all boards and check the primary > bus by uboot. If "isa" is useful why MPC8541CDS and MPC8555CDS has no > "isa" node in device tree but has ISA bridge under PCI controller? > > Thanks. > - Jia Hongtao
Hi Kumar and Ben, Do you have any idea on this? Thanks. - Jia Hongtao _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
