On 8/3/08, Wolfgang Denk wd@denx.de wrote:
In message 9e4733910808021858i766307b1q45b5bace59996d03@mail.gmail.com you wrote:
What about creating a tool that parses a device tree and creates (or updates) the board header file? This will retain compatibility with other platforms, clean up the existing header files (they won't need to contain as much information), and reduce the amount of changes to U-Boot itself.
That's a good idea. I have used variation on this concept in the past and they have worked out well.
A much more powerful concept is to have U-Boot read and interpret the DT dynamically - only then can you use the same U-Boot binary image on different board configurations, which is an important feature for many board vendors.
I don't disagree with this but it is a lot more work.
A perfect tool would take a fully populated DTS file and use it to dynamically generate all of the needed header files to build uboot. More info would need to be added to the DTS file like DRAM timings, etc. But a DTS file is good place to track all of that info. The generated uboot image could contain a copy of the DTB and feed it to Linux. Allow the user to override the embedded DTB if necessary.
No, no, no. The DTB *must not* be included with the U-Boot image. It shall always be kept separate so we canupdate it independently - otherwise you lose a lot of advantages.
A DTB is only about 8K. I was thinking that a user supplied one would override the one contained inside uboot.
Best regards,
Wolfgang Denk
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