Quote:
Originally Posted by eureka
Yes.
To initialize DRAM one must setup a bunch of registers. The exact initialization sequence could be found in Amazon's U-Boot source.
Initialization (writing to registers) could be made with the help of ordinary code or through DCD.
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Could you give me a hint as to which file I should start looking at?
At the moment, I'm completely overwhelmed by hundreds of new acronyms and completely confused by the structure of the u-boot source. The only thing I found so far is the include/configs/imx50_yoshi.h file (heck, I'm not even sure if that is the right one!), which seems to include the "scripts" (actually environment definitions) that are run on startup, and a bunch of #defines. But there isn't any actual code in there... so where is it?
Quote:
Originally Posted by eureka
And remember, just a part of 128kb of OCRAM is free for arbitrary use (refer to Reference Manual for details).
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Hehe, nope. I got at least that one right - only 128k out of 128M are usable, but I knew that. Edit: duh... only 72k, actually (page 425). It seems like I really have to read almost all of the 3000 pages to (try to) understand this beast.
Edit: I just realized that it's probably largely irrelevant, because there's none of our code being run - after all, the device is in USB Downloader mode, so that's *before* u-boot is even launched. And if the DRAM isn't accessible, then there's nothing we can do about it.
Which means that the magic will have to be done from u-boot, so we're probably back to the tftp idea. But any hints about u-boot (or in particular, where to look for in the code if I want to enable that tftp stuff) are still welcome!