[PATCH] kconfig: Add PCIe devices to s390xx machines

[PATCH] kconfig: Add PCIe devices to s390xx machines

[Cédric Le Goater]

It is useful to extend the number of available PCI devices to KVM guests
for passthrough scenarios and also to expose these models to a different
(big endian) architecture.

Signed-off-by: Cédric Le Goater <clg@redhat.com>
---
 hw/s390x/Kconfig | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hw/s390x/Kconfig b/hw/s390x/Kconfig
index 5e7d8a2bae8b..373f38adcd6b 100644
--- a/hw/s390x/Kconfig
+++ b/hw/s390x/Kconfig
@@ -10,3 +10,7 @@ config S390_CCW_VIRTIO
     select SCLPCONSOLE
     select VIRTIO_CCW
     select MSI_NONBROKEN
+    select PCI_EXPRESS
+    select E1000E_PCI_EXPRESS
+    select IGB_PCI_EXPRESS
+    select USB_XHCI_PCI
-- 
2.41.0

Re: [PATCH] kconfig: Add PCIe devices to s390xx machines

[Thomas Huth]

On 04/07/2023 11.32, Cédric Le Goater wrote:
> It is useful to extend the number of available PCI devices to KVM guests
> for passthrough scenarios and also to expose these models to a different
> (big endian) architecture.

Maybe mention that these devices can work on s390x since they support MSI-X 
? (While most of the other devices don't work on s390x since they only 
support legacy interrupts)

> Signed-off-by: Cédric Le Goater <clg@redhat.com>
> ---
>   hw/s390x/Kconfig | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/hw/s390x/Kconfig b/hw/s390x/Kconfig
> index 5e7d8a2bae8b..373f38adcd6b 100644
> --- a/hw/s390x/Kconfig
> +++ b/hw/s390x/Kconfig
> @@ -10,3 +10,7 @@ config S390_CCW_VIRTIO
>       select SCLPCONSOLE
>       select VIRTIO_CCW
>       select MSI_NONBROKEN
> +    select PCI_EXPRESS
> +    select E1000E_PCI_EXPRESS
> +    select IGB_PCI_EXPRESS
> +    select USB_XHCI_PCI

Please don't use "select" here - you still want these devices to be disabled 
in case you run configure with "--without-default-devices".

You can use "imply" instead of "select" instead.

  Thomas

Re: [PATCH] kconfig: Add PCIe devices to s390xx machines

[Philippe Mathieu-Daudé]

On 4/7/23 11:32, Cédric Le Goater wrote:
> It is useful to extend the number of available PCI devices to KVM guests
> for passthrough scenarios and also to expose these models to a different
> (big endian) architecture.
> 
> Signed-off-by: Cédric Le Goater <clg@redhat.com>
> ---
>   hw/s390x/Kconfig | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/hw/s390x/Kconfig b/hw/s390x/Kconfig
> index 5e7d8a2bae8b..373f38adcd6b 100644
> --- a/hw/s390x/Kconfig
> +++ b/hw/s390x/Kconfig
> @@ -10,3 +10,7 @@ config S390_CCW_VIRTIO
>       select SCLPCONSOLE
>       select VIRTIO_CCW
>       select MSI_NONBROKEN
> +    select PCI_EXPRESS

Can zPCI plug legacy PCI devices? I'd expect not, only PCIe
devices. Then this patch would become:

-- >8 --
@@ -5,7 +5,7 @@ config S390_CCW_VIRTIO
      imply VFIO_AP
      imply VFIO_CCW
      imply WDT_DIAG288
-    select PCI
+    select PCI_EXPRESS
      select S390_FLIC
      select SCLPCONSOLE
      select VIRTIO_CCW
---