Re: [PATCH 1/5] hw/ppc/pegasos2: Initialize VT8231 PCI IRQ router

[Mark Cave-Ayland]

On 23/02/2023 20:20, Bernhard Beschow wrote:

> The firmware of the real PegasosII board routes all PIRQx to IRQ9, so do
> the same in QEMU. The PCI_INTERRUPT_LINE registers of the respective
> internal PCI functions are already initialized with IRQ9 which are
> currently used for routing.
>
> Note that the PCI interrupt router isn't implemented yet in the VIA
> south bridges. This change has therefore no effect until this happens.
>
> Inspired-by:
> <c046d77c20875c8cd8bfdc79b4619a98ffd0bf33.1677004415.git.balaton@eik.bme.hu>
> ("hw/ppc/pegasos2: Fix PCI interrupt routing")
>
> Signed-off-by: Bernhard Beschow <shentey@gmail.com>
> ---
>   hw/ppc/pegasos2.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/hw/ppc/pegasos2.c b/hw/ppc/pegasos2.c
> index a9563f4fb2..41688699eb 100644
> --- a/hw/ppc/pegasos2.c
> +++ b/hw/ppc/pegasos2.c
> @@ -268,6 +268,12 @@ static void pegasos2_machine_reset(MachineState *machine, 
> ShutdownCause reason)
>                                 PCI_INTERRUPT_LINE, 2, 0x9);
>       pegasos2_pci_config_write(pm, 1, (PCI_DEVFN(12, 0) << 8) |
>                                 0x50, 1, 0x2);
> +    pegasos2_pci_config_write(pm, 1, (PCI_DEVFN(12, 0) << 8) |
> +                              0x55, 1, 0x90);
> +    pegasos2_pci_config_write(pm, 1, (PCI_DEVFN(12, 0) << 8) |
> +                              0x56, 1, 0x99);
> +    pegasos2_pci_config_write(pm, 1, (PCI_DEVFN(12, 0) << 8) |
> +                              0x57, 1, 0x90);
>   
>       pegasos2_pci_config_write(pm, 1, (PCI_DEVFN(12, 1) << 8) |
>                                 PCI_INTERRUPT_LINE, 2, 0x109);

The patch looks okay, but I think the commit message doesn't quite represent why it 
is required. I presume this configures the PCI IRQ router in the same way as the 
firmware so that it is possible to launch Linux directly with -kernel?


ATB,

Mark.