Il 06/11/24 19:49, frank-w@xxxxxxxxxxxxxxx ha scritto:
Hi
any new state on this??
https://patchwork.kernel.org/project/linux-mediatek/patch/20240608080530.9436-2-linux@xxxxxxxxx/
regards Frank
I had a look at this one - and this is the situation:
1. Your bootloader supports loading DTBO, so you can indeed use DTBOs
2. Validation of the DTSO can still be done during kernel build without adding
all of those possible X+Y+Z pre-joined DTBs
3. What if your hardware had more than 20 possible configurations?
Would you write 20 different Makefile entries? "sd+nand+nor",
"sd+nand-withoutnor", "emmc+nand+nor", "emmc+nand-withoutnor",
"emmc+sd+nor", "emmc+sd-withoutnor", "ufs+emmc", "ufs+emmc+sd",
"ufs+sd+nor", "ufs+emmc-withoutnor", "ufs+sd-withoutnor", ......
Looks messy and unfeasible.
However, this is not a *global* no: I'm happy that your bootloader does support
loading DTBOs and, as far as I remember, even uses straps to vary the DTB(o) to
actually load - which is something proper and great... so it's a *no* for you,
but more than just a no, this is "why are you treating your proper bootflow
like it was a broken one?!?!" :-)
If anyone finds themselves in a situation in which there's no way to update a
bootloader (and that unfortunately happens more often than anyone would like
to see...) and in which the only way to apply DTBOs is to pre-overlay them
during the kernel build, then that's fine and I would (if nice and clean)
accept that.
But again, you're not in this kind of situation - and you're lucky that you're
dealing with a fully open device with a proper bootloader and bootflow: don't
ruin it like that!
Instead, if necessary, update the userspace tools that you're using to deal with
multiple DTBOs during system upgrades: that's the right thing to do at this point.
Cheers,
Angelo
