It looks new BBG uses "raw mode" of rom code's memory booting. MLO goes at the sector #256 (in fact at #257, CH goes at #256). Configuration Header (CH) directs the rom code to load the "raw" image from the next sector, where GH and your image come. In fact all this thing is abysmally and incorrectly described in TI TRM (for example it says rom code doesn't support the raw mode for eMMC while it does, and it doesn't say that in the raw mode, rom code, after identifying CH, expects the raw image at the next sector and not just right after CH bits, and CH and TOC are documented absolutely inconsistently etc.). I've figured out how and why this works thanks to people at TI community forum, when had found that my eMMC actually does have MLO despite accordingly to the TRM it shouldn't. Now they switched to the raw mode. Rom code for the raw mode checks locations (LBA's) #0, #256, #512 and #768. Looks here it uses the second.
пʼятниця, 4 листопада 2016 р. 14:50:38 UTC+2 користувач Paul Plankton написав: > > OK just to understand this: > > To clarify, the 512 bytes is just for the first sector of the MBR that has >> the partition table in it. We actually skip by that to an offset of 128k. >> Based on Robert's instructions, 256 *k*bytes (384-128) is reserved for >> the MLO. Of course, MLO needs to fit in the internal RAM of the processor >> since this is the first place the DDR is configured, so your MLO would >> never get to be that large. >> > > First 512 Bytes are the MBR including the partition table and some other > "magic" things. Then the MLO-file is appended (directly at 512 bytes or > with an offset of 128k?). > > But: who is responsible to jump into the MLO-"file" at it's position in > flash? Isn't there a special MBR-code needed that knows where to continue? > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/d8f8c9dd-8bef-4d95-b34a-676f5a9732eb%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
