Hi Rob, On Fri, 6 Oct 2023 at 10:11, Rob Herring <robh@xxxxxxxxxx> wrote: > > On Fri, Oct 06, 2023 at 10:37:41AM +0200, Michael Walle wrote: > > Hi, > > > > > > I'm still not sure why that compatible is needed. Also I'd need to > > > > change > > > > the label which might break user space apps looking for that specific > > > > name. > > > > > > > > Also, our board might have u-boot/spl or u-boot/spl/bl31/bl32, right > > > > now > > > > that's something which depends on an u-boot configuration variable, > > > > which > > > > then enables or disables binman nodes in the -u-boot.dtsi. So in linux > > > > we only have that "bootloader" partition, but there might be either > > > > u-boot+spl or u-boot+spl+bl31+bl32. > > > > > > > > Honestly, I'm really not sure this should go into a device tree. > > > > > > I think we might be getting a bit ahead of ourselves here. I thought > > > that the decision was that the label should indicate the contents. > > > If you have multiple things in a partition then it would become a > > > 'section' in Binman's terminology. Either the label programmatically > > > describes what is inside or it doesn't. We can't have it both ways. > > > What do you suggest? > > > > As Rob pointed out earlier, it's just a user-facing string. I'm a bit > > reluctant to use it programatically. > > In general, yes, but the partition stuff has long (and still) uses > label. As long as the values the tools understand are documented (which > we don't normally do for label), I don't care so much. That's my > opinion as long as this is shared with fixed-partitions. If it is not > and there's little reason to use label, then absolutely, I think > 'compatible' makes more sense. OK I will try to drop the sharing with fixed-partitions > > > Taking my example again, the string "bootloader" is sufficient for a > > user. He doesn't care if it's u-boot with spl or u-boot with tfa, or > > even coreboot. It just says, "in this partition is the bootloader". > > If you have an "bootloader" image you can flash it there. > > These days, there's generally not just 1 bootloader in the boot flow. > Maybe there's 1 image, maybe not. Being more specific is hardly ever a > bad thing. Only when the number of specific things becomes multiple 10s > or 100s of them does it become a problem. > > > > If it has a label "u-boot" and I want to switch to coreboot, will > > it have to change to "coreboot"? I really don't think this is practical, > > you are really putting software configuration into the device tree. > > On the input side (to binman), yes it is config, but on the output side > (to the running system) we are saying what's there. > > > > > At present it seems you have the image described in two places - one > > > is the binman node and the other is the partitions node. I would like > > > to unify these. > > > > And I'm not sure that will work for all the corner cases :/ > > > > If you keep the binman section seperate from the flash partition > > definition you don't have any of these problems, although there is > > some redundancy: > > - you only have compatible = "binman", "fixed-partition", no further > > compatibles are required > > - you don't have any conflicts with the current partition descriptions > > - you could even use the labels, because binman is the (only?) user > > > > But of course you need to find a place where to put your node. > > And remove it. We don't need 2 sources of truth in the DTB. I would certainly prefer to have one...I think using 'label' for the existing case and 'compatible' for the new one could be a reasonable compromise, so I will send v3. Regards, Simon
