Re: [Qemu-devel] [PATCH v3] pci : Add pba_offset PCI quirk for Chelsio T5 devices

[Bandan Das <bsd@redhat.com>]

Gabriel Laupre <glaupre@chelsio.com> writes:
...
> +    /* Test the size of the pba variables and catch if they extend outside of
> +     * the specified BAR. If it is the case, we have a broken configuration or
> +     * we need to apply a hardware specific quirk. */
> +    if (vdev->msix->table_offset >=
> +        vdev->bars[vdev->msix->table_bar].region.size ||
> +        vdev->msix->pba_offset >=
> +        vdev->bars[vdev->msix->pba_bar].region.size) {
> +
> +        PCIDevice *pdev = &vdev->pdev;
> +        uint16_t vendor = pci_get_word(pdev->config + PCI_VENDOR_ID);
> +        uint16_t device = pci_get_word(pdev->config + PCI_DEVICE_ID);
> +
> +        /* Chelsio T5 Virtual Function devices are encoded as 0x58xx for T5
> +         * adapters. The T5 hardware returns an incorrect value of 0x8000 for
> +         * the VF PBA offset. The correct value is 0x1000, so we hard code that
> +         * here. */
> +        if (vendor == PCI_VENDOR_ID_CHELSIO && (device & 0xff00) == 0x5800) {
> +            vdev->msix->pba_offset = 0x1000;

For the rare case where table_offset is wrong for the device being checked for
above and pba_offset is actually correct, shouldn't we fail ?

> +        } else {
> +            error_report("vfio: Hardware reports invalid configuration, "
> +            "MSIX data outside of specified BAR");

Since we are printing anyway, and we have already made the check above, why
not print exactly what's wrong instead of "MSIX data" ?

> +            return -EINVAL;
> +        }
> +    }
> +
>      trace_vfio_early_setup_msix(vdev->vbasedev.name, pos,
>                                  vdev->msix->table_bar,
>                                  vdev->msix->table_offset,
> diff --git a/include/hw/pci/pci_ids.h b/include/hw/pci/pci_ids.h
> index 49c062b..d98e6c9 100644
> --- a/include/hw/pci/pci_ids.h
> +++ b/include/hw/pci/pci_ids.h
> @@ -114,6 +114,8 @@
>  #define PCI_VENDOR_ID_ENSONIQ            0x1274
>  #define PCI_DEVICE_ID_ENSONIQ_ES1370     0x5000
>  
> +#define PCI_VENDOR_ID_CHELSIO            0x1425
> +
>  #define PCI_VENDOR_ID_FREESCALE          0x1957
>  #define PCI_DEVICE_ID_MPC8533E           0x0030