Re: Questions about IOMMU & PCIe switch

[Clemens Ladisch]

Raimonds Cicans wrote:
> We have two kinds of PCIe cards:
> A1 - based on chip B
> A2 - based on same chip B but behind PCIe switch
>
> Card A1 work flawlessly in any configuration,
> but card A2 work flawlessly only if system
> lack IOMMU or have disabled IOMMU

In theory, such a switch should be transparent.

> Do we have to treat card with PCIe switch in special way?

No.  But the switch has to work correctly, and driver must be
written correctly.

Which switch?  Which driver?


Regards,
Clemens
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