[edk2-devel] [PATCH v2 1/2] OvmfPkg/Bhyve: add USB support
Michael Brown
mcb30 at ipxe.org
Fri Jul 2 12:21:32 UTC 2021
On 02/07/2021 00:31, Peter Grehan wrote:
>>>>> bhyve doesn't (and will likely never) support Uhci/Ehci
>>>>> controllers so those lines can be removed.
>>>>
>>>> Is it possible to pass such a controller by PCI-Passthrough to a VM?
>>>> If it's possible, I would keep these lines.
>>>
>>> Uhci/Ehci only support legacy interrupts and that isn't supported
>>> by bhyve PCI passthru.
>>
>> Is that a detail of the current implementation, or a fundamental
>> limitation in the bhyve architecture?
>
> Only two choices ? :) Maybe half way between those points.
When there is no fundamental limitation, i.e. when a future version of
the hypervisor may be able to support the feature with no changes to the
firmware, then it would be good practice to leave the drivers enabled.
Doing so avoids creating an unnecessarily tight coupling between the
hypervisor and firmware versions.
More importantly: does it even matter that the hypervisor doesn't
support passthrough of PCI legacy interrupts? UEFI operates on a
polling basis, with the only active interrupt being some kind of
periodic timer. Where do you see any requirement for legacy interrupts
in the UHCI/EHCI drivers?
Thanks,
Michael
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#77447): https://edk2.groups.io/g/devel/message/77447
Mute This Topic: https://groups.io/mt/83755216/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-
More information about the edk2-devel-archive
mailing list