Hi Ard, The xHCI controller is initialized with its microcode by the VPU firmware, if I understood correctly, synchronously. When RPI_MBOX_NOTIFY_XHCI_RESET finishes, the XHCI controller is ready to go.
So this is not any more unsafe than any of the other mailbox calls. To be honest, I think RpiFirmwareDxe should be cleaned up to replace the useless spinlocks (there's no multiprocessing component) with a TPL manip (I checked SynchonizationLib and it doesn't touch the TPL) Applying your other feedback now... A ________________________________ From: devel@edk2.groups.io <devel@edk2.groups.io> on behalf of Ard Biesheuvel via groups.io <ard.biesheuvel=arm....@groups.io> > + > + Status = MailboxTransaction (Cmd->BufferHead.BufferSize, > RPI_MBOX_VC_CHANNEL, &Result); > + So this pokes the XHCI controller via its config space? Is it safe to do that without raising the TPL? What happens if another config space access occurs concurrently? A -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#60493): https://edk2.groups.io/g/devel/message/60493 Mute This Topic: https://groups.io/mt/74596471/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
