On 20/04/2021, Jan Kiszka <[email protected]> wrote: > On 20.04.21 02:56, Peng Fan wrote: >>> Subject: Re: Arm zero exits and zynqmp ATF SDEI-enabling patch >>> upstreaming >>> >>> On 19.04.21 15:28, Peng Fan wrote: >>>>> Subject: Arm zero exits and zynqmp ATF SDEI-enabling patch >>>>> upstreaming >>>> >>>> Not sure whether you are aware. >>>> FYI: SDEI not work with OP-TEE for now. >>>> >>> >>> Thanks for the info. None of the targets I played with - so far - had >>> OP-TEE >>> included. AT-F bug or a conceptual conflict? >> >> The design of SDEI not take TEE into consideration. SDEI requires secure >> interrupts >> taken into EL3, but op-tee requires non-secure FIQ taken into secure EL1.
This is new to me. I though that FIQs were could only be secure, reason why they can only be used in EL3 and secure EL1. If non-secure FIQs are an option we should be able to skip patching the ATF altogether. > Do you mean the implementation in TF-A? Or even the specification of the > service?? My understanding of SDEI is that, even though the method of signaling is not determined in theory, in practice they use FIQs, and then you incur in the same problem we're trying to solve with IRQs that routed to EL1 cannot be used in EL2: if you use FIQs as a signaling method for SDEI in EL3, you cannot use FIQs in other exception levels, like in secure EL1 OPTEEs. > Jan > > -- > Siemens AG, T RDA IOT > Corporate Competence Center Embedded Linux -- Angelo -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/CADiTV-3sBJs3sqd1fyOV8tLamorCihJ%2B15mT07ZY-kREsNrBfQ%40mail.gmail.com.
