On 10.07.19 18:28, Ralf Ramsauer wrote: > > On 7/10/19 6:13 PM, Jan Kiszka wrote: >>> Ok, there's one chance left: According to lspci, the device actually >>> supports MSI. It's just not being used by Linux. Maybe I can somehow >>> convince Linux to switch to MSI. >> Latest kernel already? >> > > I'm using the 4.19-rt jailhouse. Do you know of any relevant changes > upstream? Anyway, it's worth a try, let me test upstream... > > At least for 4.19, it looks like I'm not able to easily switch to MSI. > At the moment, I don't even understand why the kernel actually uses > legacy interrupts, while MSI cap is present. Something is odd there, I'd > expect that MSI is, if available, the perefered method. But even the > root-cell after boot won't enable MSI. Still investigating... > > I hope that I can switch to MSI with maybe a dirty hack, but I need more > time to dig through the kernel's PCI stack (PCI starts bugging me). You > can find things there you never wanted to know! :-)
I suspect you are using some 8250 derivative with a similar driver: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=172c33cb61da0df5ccbdf1a8e736c8837d165a00 Check your concrete driver for its interrupt allocation. Jan -- Siemens AG, Corporate Technology, CT RDA IOT SES-DE Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/c6c3d947-d6ac-be55-6094-9743a61ccbbd%40siemens.com. For more options, visit https://groups.google.com/d/optout.
