On 2024-03-12 09:58, Ard Biesheuvel wrote:
On Tue, 12 Mar 2024 at 17:56, Leif Lindholm <[email protected]> wrote:On 2024-03-12 09:50, Ard Biesheuvel wrote:On Tue, 12 Mar 2024 at 17:38, Leif Lindholm <[email protected]> wrote:On 2024-03-12 08:17, Ard Biesheuvel wrote:From: Ard Biesheuvel <[email protected]> NonCoherentIoMmuSetAttribute() does nothing except return EFI_UNSUPPORTED. This was fine when it was introduced, but now, the PCI bus driver will fail a PCI I/O Map() operation if the SetAttributes fails. So return EFI_SUCCESS instead.It's unclear to me why this change is safe (looking forward). Does NonCoherentIoMmuDxe also imply no IoMmu actually exists?Basically. NonCoherentIoMmuDxe is just a vehicle to allow NonCoherentDmaLib to be plugged into the PCI host bridge driver. It is not intended to ever do anything more than that.Not that it needs to happen for this (Reviewed-by: Leif Lindholm <[email protected]>) but maybe we ought to consider renaming it then? DummyIoMmuDxe?Fair point. Or PassThroughIoMmuDxe perhaps?
Works for me. Or, hmm...Is there a risk that sounds a bit like a driver that actively configures IoMmus into passthrough mode?
/
Leif
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#116697): https://edk2.groups.io/g/devel/message/116697
Mute This Topic: https://groups.io/mt/104886877/21656
Group Owner: [email protected]
Unsubscribe: https://edk2.groups.io/g/devel/unsub [[email protected]]
-=-=-=-=-=-=-=-=-=-=-=-
