Dear Simon Glass,
In message
CAPnjgZ0bbhvZ1VPwY=0y9YZJdf+EOBgyKKVPFuAkBqy2z4L3HA@mail.gmail.com you wrote:
Just a quick Q. What is the ultimate intent here? Should we be aiming to have U-Boot copy and decompress the data into RAM ready for Linux?
Yes.
Rigth from the beginning of PPCBoot / U-Boot we designed it that U-Boot would do all needed steps to verify, load and uncompress an image. It make no sense to attach the uncompression and loading code to each and every image, and to download it and store it again and again and again. This works really well for example on Power, only ARM is one of the examples where the PTB never bothered to acquaint themself with ideas that went beyond the capabilities of Blob or similar boot loaders.
Right, there's no negotiation between linux and uboot on this topic. I think this is going on for ages now.
In theory this should be slightly faster since U-Boot already has the data in its cache. I think zImage now supports having an FDT inside but what is the advantage of zImage over a uImage with compressed portions?
There is none. Also, there is no advantage in attaching the DT blob to the Linux image/. This is only of use to braindead boot loaders.
Best regards,
Wolfgang Denk