[...] > > > > > > > > Same here. On top of that the bloblist has a few items in there, e.g a > > > > TPM eventlog. What are we going to do? Add a Kconfig for each item? > > > > > > No, but that is just a straw man. The DT is special and U-Boot reports > > > where it comes from. > > > > The story is identical to the EventLog. It's 'special' as well and > > U-Boot has to pick it up, otherwise the hardware and the EventLog will > > end up with different values > > Why are you talking about event log? Let's stick to the topic at hand.
We are. The reason I bring this up is pretty obvious. It has identical properties to the DT, and I *dont* want a Kconfig option to enable or disable it. > > > > > > > > > > > > > > This has been going back and forth for a while. I've lost count of how > > > > many times I repeated the same proposal, but here it goes again. We > > > > have OF_BOARD and BLOBLIST options. The bloblist and its properties > > > > are scannable at runtime. Can't we use the combination of these 2 can > > > > be used to imply we expect things from a bloblist. If we want to be > > > > stricter in the future and explicitly expect the DT from a bloblist, > > > > we could add a Kconfig option failing the boot if that's missing. > > > > > > I would like to have that Kconfig option now, not later. In my mind, > > > the boot must be deterministic, so that if OF_BLOBLIST is enabled, the > > > DT must come from there, or it is an error. > > > > And how is what I proposed not deterministic? What prevents us from > > adding that Kconfig option now? > > The only difference is that by default, U-Boot will try bloblist -> > > board-specific method unless a Kconfig option prevents the fallback. > > I've been working with vendors and helping them implement the firmware > > handoff spec in their proprietary bootloaders and Raymond contributed > > the implementation for TF-A. At the same time, I am pretty sure > > vendors will need time to implement this properly. I don't see how > > adding an implicit Kconfig option will help them push this forward. > > > > IOW I prefer U-Boot to *always* scan for a bloblist as the first > > discovery DT method (unless the DT comes bundled with U-Boot), rather > > than expecting users to turn a Kconfig knob. > > It is the 'unless the DT comes bundled with U-Boot' which I am talking > about, but I now have a better understanding of the problem here. > > I don't want CONFIG_BLOBLIST to mean that the DT comes from a > bloblist. But it doesn't mean that. It means 'try to scan the bloblist for a DT first'. > Simply put, I want to be able to use the U-Boot DT during > development, without needing to rebuild some prior stage or update > some other project. So I would like the use of bloblist to be behind > an OF_BLOBLIST option. That's easy instead of OF_BOARD use OF_EMBED or OF_SEPARATE? > > From Tom's email and your other reply, it seems that we could all live > with an OF_BLOBLIST option to enable DT-in-bloblist, making it > optional but default 'y'? > > > > > > > > > Also, repeating it doesn't make the proposal good. We agreed that > > > OF_BOARD would eventually go away, so building on top of it is not > > > setting us up for the future. > > > > No, we didn't [0]. In fact, I said I don't see OF_BOARD *ever* going > > away. The only thing I suggested was to rename it > > Well I'm just not sure what is going on. Use of bloblist should not > require board-specific code. It should be a generic mechanism, in > fdtdec_setup() It doesn't, we never asked for that. There's even code in a previous iteration from me showing exactly what I had in mind. We always said scan for a bloblist if OF_BOARD is selected, in priority, and if you don't find a DT try a board-specific method (and add a Kconfig option to fail the boot if required). > > There are too many cooks in this kitchen right now, I'll try another > spin of my patch. I really don't like another OF_XXXXXXX for determining where the DT comes from, but I've explained my opinion way too many times. I'll let you and Tom decide on this Thanks /Ilias > > > > > [...] > > > > [0] > > https://lore.kernel.org/u-boot/cac_iwjkrktm4spyxpoddartj41a553vde+xm5gz3+jsntfq...@mail.gmail.com/ > > > > Regards, > Simon