[ +Sinan ] On Thu, Aug 25, 2016 at 07:59:17PM +0100, Marc Zyngier wrote: [...] > > Thanks, Marc! It works, I tested on current X-Gene platforms that uses > > GICv2 and GICv2m. > > > > Will you commit this change? It will be a huge help as going with > > interrupt link will require firmware change. > > Not for the time being. We now have an understanding of *why* things do > not work, but Lorenzo seems to have a good grasp on what we can do to > address it correctly, and we should explore this first. If (and only if) > there is a consensus that firmware already does all it should, then > I'll turn this hack into a proper series. For the records, it is a discussion that already took place: https://lkml.org/lkml/2016/3/14/923 As I have said there are already ARM64 systems with ACPI tables out there using PCI interrupt links; I doubt that Qualcomm systems allow to reconfigure the GIC interrupt pin allocated to legacy PCI IRQs through interrupt links _SRS (hey it is *empty* :)), therefore: a) Some (the above is just an example from the mailing lists I am not picking on anyone it is just for the sake of this discussion, I have not dumped all ARM partners _PRT from their ACPI tables to check) ACPI tables must be rewritten because they are not FW compliant OR b) We allow PCI interrupt links to be used for static interrupt configurations OR c) We ignore the polarity flag (only for PCI legacy IRQs ? I wonder how GIC code can detect from which part of the kernel the interrupt request is coming, unless we implement an ACPI-PCI-legacy-IRQ-special gem) Comments ? Lorenzo -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
