On 3/5/14, 8:21 PM, Mathias Gottschlag wrote: [...] > Also, I don't know whether everybody knows about it (I guess everybody > does by now), but I have a couple of traces from the early firmware boot > process which just wait to be decoded with a script similar to yours: I should add that I've reversed engineered the RAM init code from the boot ELF and have reproduced it as a small chunk of assembler --- I have a version of PiFace which uses it. But as it's based on reverse engineering I'm not sure if I can safely show it to anyone. It should certainly be a lot easier to understand than the raw traces. (The boot ROM, BTW, has lots of support for exotic RAM configurations of many different manufacturers and sizes. Stripping everything out but what's actually supported on the Raspberry Pi simplifies it hugely. e.g. there's a complete separate code path which can be selected via a run-time value which is always a constant 0.) [...] > This will probably be not as useful once there is > an open source firmware released, but even then I doubt they will > release full documentation, so some reverse engineering of this kind > will probably still be necessary. As you might have gathered, I'm particularly hoping for open source RAM init code... -- ┌─── ｄｇ＠ｃｏｗｌａｒｋ．ｃｏｍ ───── http://www.cowlark.com ───── │ │ "You cannot truly appreciate _Atlas Shrugged_ until you have read it │ in the original Klingon." --- Sea Wasp on r.a.sf.w
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