Hi Bjorn, On Mon, Aug 28, 2017 at 1:59 PM, Tim Harvey <tharvey@xxxxxxxxxxxxx> wrote: > On Mon, Aug 28, 2017 at 7:23 AM, Lucas Stach <l.stach@xxxxxxxxxxxxxx> wrote: >> Hi all, >> >> this small series tries to fix/workaround a serious design flaw of the DWC PCIe >> host controller: it is unable to work with both legacy and MSI IRQs enabled at >> the same time. As soon as the first MSI is enabled in the DWC MSI controller, >> the host stops forwarding legacy IRQs. >> >> If the MSI controller is present, MSIs will be used for the PCIe port services >> IRQs, leaving endpoint devices which don't support MSIs unable to raise IRQs. >> It is only safe to enable the MSI controller if it is validated that all PCIe >> devices and drivers in the system support working MSIs. As most devices >> support falling back to using legacy PCIe IRQs if MSI support is missing it is >> much safer to disable the MSI by default and only enable it on validated >> systems. >> >> Feedback welcome. >> >> Regards, >> Lucas >> >> Lucas Stach (3): >> PCI: designware: only register MSI controller when MSI irq line is >> valid >> PCI: imx6: allow MSI irq to be absent >> ARM: dts: imx6qdl: remove MSI irq line >> >> .../devicetree/bindings/pci/fsl,imx6q-pcie.txt | 8 ++++---- >> arch/arm/boot/dts/imx6qdl.dtsi | 2 -- >> drivers/pci/dwc/pci-imx6.c | 23 +++++++++++----------- >> drivers/pci/dwc/pcie-designware-host.c | 4 ++-- >> 4 files changed, 17 insertions(+), 20 deletions(-) >> > > Lucas, > > Thank you for following up on this! > > I tested it with and without the third patch that removes msi from the > dt thus with both an ath9k 802.11 device which only supports legacy > interrupts and a Marvell sky2 device which supports msi as well as > legacy interrupts and it works as expected: > - without msi enabled in dts (default): both sky2 and ath9k work > - with msi enabled in dt: sky2 works ath9k does not > > Tested-by: Tim Harvey <tharvey@xxxxxxxxxxxxx> Any comments about this series?
