On Tue, Aug 9, 2022 at 7:07 PM Elliot Berman <quic_eberman@xxxxxxxxxxx> wrote: > > On 8/9/2022 6:13 AM, Robin Murphy wrote: > > [drive-by observation since one thing caught my interest...] > > > Appreciate all the comments. > > Jassi, > > I understood you have talked with some of our folks (Trilok and Carl) a > few years ago about using the mailbox APIs. We were steered away from > using mailboxes then. Is that still the recommendation today? > Neither I nor Google remember any such conversation. Doorbell had always been supported by the api. It was the doorbell-mode of _mhu_ controller that had some contention. I haven't read the complete history of Gunyah yet, but from a quick look it uses the hvc/smc instruction as the "physical link" between entities (?). zynqmp-ipi-mailbox.c is one driver that uses smc in such a manner. And I know there are some platforms that don't call hvc/smc under mailbox api and I don't blame them. Let me educate myself with the background and get back.... unless you want to summarize a usecase that you doubt is supported. Thanks.
