On Mon, 11 Jan 2021 at 01:11, Nathan Chancellor <natechancel...@gmail.com> wrote: > > On Tue, Sep 01, 2020 at 12:40:42PM +0200, Philippe Mathieu-Daudé wrote: > > We call pci_register_root_bus() to register 4 IRQs with the > > ppc4xx_pci_set_irq() handler. As it can only be called with > > values in the [0-4[ range, replace the pointless warning by > > an assert(). > > > > Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> Hopefully reporting this here is okay, I find Launchpad hard to use but > I can file it there if need be. > > The assertion added by this patch triggers while trying to boot a > ppc44x_defconfig Linux kernel: This is the same issue reported here by Guenter: https://lore.kernel.org/qemu-devel/3f0f8fc6-6148-a76e-1088-b7882b0bb...@roeck-us.net/ It's still there in master (you can see it if you apply my fix https://patchew.org/QEMU/20210111171623.18871-1-peter.mayd...@linaro.org/ to get past the earlier kernel panic). The QEMU code as it stands for the Bamboo PCI interrupts is clearly wrong. The problem is that I don't know what the hardware's actual behaviour is, so it's hard to fix the model... A comment in hw/ppc/ppc4xx_pci.c claims "On Bamboo, all pins from each slot are tied to a single board IRQ." Code in hw/ppc/ppc440_bamboo.c wires four irq lines from the PCI controller up to UIC lines 25, 26, 27, 28. Does anybody have documentation for this board ? What is Linux expecting the PCI IRQ wiring to be (not necessarily an indication that that's what the h/w does, but a useful clue :-)) ? thanks -- PMM
