-------- Original-Nachricht -------- > Datum: Sun, 15 Mar 2009 09:38:26 +0100 > Von: "Roderick Colenbrander" <thunderbir...@gmx.net> > An: "Gerhard Pircher" <gerhard_pirc...@gmx.net>, linuxppc-dev@ozlabs.org > Betreff: Re: DTS file PCI / i8259 for Xilinx ML510
> > > At some point in the file they create some (dummy?) pcie section in > > > which they define a uli1575, an isa bus and attached to that isa bus > > > a i8259. Is this the correct way of doing things? The i8259 driver > > > seems to use io ports 0x20-21/0xa0-0xa1/0x4d0-0x4d1 those are also > > > defined below but how are those mapped to the south bridge? I have > > > seen some code in kernel/isa-bridge, is that code indeed responsible > > > for setting up these ports? > > Yes, the pcie node is the PCI host bridge node and the uli1571 node > > acts as PCI2ISA bridge node. AFAIK their ranges properties are parsed > > by pci_process_bridge_OF_ranges(). > > IIRC the code in kernel/isa-bridge is used for 64bit PPC machines only > > for now. The I/O addresses for the i8259 PIC are currently hardcoded > > and setup (request_resource()) in sysdev/i8259.c. > > I got the i8259 south bridge working now after adding an io_base_virt > offset to all inb/outb lines in sysdev/i8259.c. Would it be worth all > the troubles to add ppc32 support to isa-bridge.c? The whole point of > the code is basically to remap the io memory to low addresses for these > 64-bit ppc systems (mainly freescale boards with a i8259 and pseries > systems with a i8259). pci_process_bridge_OF_ranges() should "ioremap" io_base_virt for you, if your board has only one PCI I/O space. It also sets isa_io_base to io_base_virt on PPC32, but expects that the ISA I/O space is mapped to PCI I/O address 0x0. Isn't that the case for your board? > As far as I have seen it is only needed for i8259 interrupt controllers. > Personally I think it would be better to pass a io base offset to > i8259_setup or so. Or perhaps do some dts file parsing in i8259.c. > I'm not sure what the proper layout would be for this in the dts file > though. I think adding an io base offset parameter to i8259_setup isn't the right way to do it. I would expect other problems too, if ISA I/O space isn't mapped 1:1 to PCI I/O space on a PPC32 system. Maybe a more experienced kernel developer can comment on this? > With those changes I mentioned to i8259.c I got some PCI devices of my > ali m1553 south bridge working. The code is ugly and I need to do > cleanups. When it is done I will submit some patches. IMHO that doesn't matter, as long as it helps people to understand your problem. :-) regards, Gerhard -- Psssst! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger01 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
