Hello, On 11.03.21 16:18, Alexandre TORGUE wrote: >> I raised this issue before with your colleagues. I still believe the correct way >> would be for the TF-A to pass down either a device tree or an overlay with the >> actual settings in use, e.g.: >> >> - Clocks/Resets done via SCMI >> - Reserved memory regions >> >> If TF-A directly boots Linux, it can apply the overlay itself, otherwise it's >> passed down to SSBL that applies it before booting Linux. > Discussing with tf-a and u-boot guys, this solution could imply hard synchronization between tf-a/u-boot. The most simple remains a "secure" dts. OP-TEE can be configured via CFG_EXTERNAL_DTB_OVERLAY to pass along an overlay that describes the reserved memory regions it uses. A similiar approach could work here. The only synchronization you need in Linux is to keep phandles that the overlay can reference. Cheers, Ahmad > > regards > Alex > >> Cheers, >> Ahmad >> >>> >>> Gabriel, can you wait a bit before sending something about SCMI in dtsi, I would like to align this strategy internally. >>> >>> Marek, Alex: thanks for your inputs. >>> >>> Regards >>> Alex >>> >>>>> The third could be the less costly. >>>> >>>> [...] >>> _______________________________________________ >>> Linux-stm32 mailing list >>> Linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx >>> https://st-md-mailman.stormreply.com/mailman/listinfo/linux-stm32 >> > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
