Re: [PATCH] hw/pci-bridge/pxb: Fix missing swizzle

[Jonathan Cameron via <qemu-devel@nongnu.org>]

On Tue, 18 Jan 2022 17:48:55 +0000
Jonathan Cameron via <qemu-devel@nongnu.org> wrote:

> From: Jonathan Cameron <jonathan.cameron@huawei.com>
> 
> pxb_map_irq_fn() handled the necessary removal of the swizzle
> applied to the PXB interrupts by the bus to which it was attached
> but neglected to apply the normal swizzle for PCI root ports
> on the expander bridge.
> 
> Result of this was on ARM virt, the PME interrupts for a second
> RP on a PXB instance were miss-routed to #45 rather than #46.
> 
> Tested with a selection of different configurations with 1 to 5
> RP per PXB instance.  Note on my x86 test setup the PME interrupts
> are not triggered so I haven't been able to test this.
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Cc: Michael S. Tsirkin <mst@redhat.com>
> Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>

Ping.

> ---
>  hw/pci-bridge/pci_expander_bridge.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c
> index 10e6e7c2ab..de932286b5 100644
> --- a/hw/pci-bridge/pci_expander_bridge.c
> +++ b/hw/pci-bridge/pci_expander_bridge.c
> @@ -192,6 +192,12 @@ static int pxb_map_irq_fn(PCIDevice *pci_dev, int pin)
>  {
>      PCIDevice *pxb = pci_get_bus(pci_dev)->parent_dev;
>  
> +    /*
> +     * First carry out normal swizzle to handle
> +     * multple root ports on a pxb instance.
> +     */
> +    pin = pci_swizzle_map_irq_fn(pci_dev, pin);
> +
>      /*
>       * The bios does not index the pxb slot number when
>       * it computes the IRQ because it resides on bus 0