Hi,
I would like to slightly modify the beagle black board. I got all the hardware content from website. But I want to know from where can I get the primary bootloaders of the design. The bootloader that runs before the u-boot. How do I program the board.??
Regards
Manu.C
The wiki does not seem to be very helpful on this point. The wiki could be improved by adding a link to TI’s Sitara bootcamp:
http://www.ti.com/lsds/ti/arm/training/OLT312000.page
Anyway, downloading the powerpoint “Giving Linux the boot” might be helpful (registration required). From that, you would find that the (stage 2 loader) SPL can reside in MMC or NAND-flash, hence no need for a fixed programmed part on the board. The stage 1 bootloader is located in the processor’s ROM.
So, one might guess that the SPL is part of the bit-baked image. Page 12 of the following Yocto project document (describing contents of meta-ti) seems to confirm this:
https://wiki.yoctoproject.org/wiki/images/b/b3/Meta-ti.pdf
Don
Sorry you don’t like the Wiki. The Wiki is not intended to duplicate the TI website. If you send me a list of the TI links you think should be on there, I will look to add a page called “TI Links”.
If registration is required, it will not appear on this Wiki. If it isn’t open and free to access, it doesn’t go on BeagleBoard.org.
Gerald
Gerald,
I did not say that I did not like the wiki. However, you pointed Manu to the wiki – which did not address his question. I was merely pointing out how the wiki might be modified to point to that information (by sending the user to the wiki, were you not inferring that the scope of the wiki included this information?).
The information on the TI site is free. They offer it under the Creative Commons ShareAlike license (same license as SRM, methinks). They seem to want to know who you are before you actually download a powerpoint, however. I was asked for my “my.ti” logon.
It is your wiki. I’m not going to tell you what to do with it.
IMHO, section 6.7 of the SRM might benefit from a few words clarifying the boot process. It might only take a few sentences to clarify that the stage 1 boot code is in the processor ROM, stage 2 (SPL) and stage 3 (Uboot) are in the eMMC or uSD as determined by the boot button status at start-up. (Most users will know that stage 3 must be in eMMC or uSD, but I am not surprised at all that they might wonder about SPL, and might try searching the schematic for programmed parts).
You seem to have taken my input personally. Please know that it was not my intent to insult you or your work on the wiki. Contrary, I am a big fan of the BBB hardware and your work. I’m sorry if I ruffled a few feathers. The intent of my post was principally to help another user.
Thanks,
Don
Don
Make you suggestions ans send them to me as indicated in the SRM. I will get them in the next version of the SRM.
Gerald
To address the Boot questions, may I suggest referring to section 26 of the AM335X Technical Reference Manual.
http://www.ti.com/litv/pdf/spruh73h
The boot order is in the System Reference Manual in sections 5.3.5. The boot mode and boot order used is documented in section 6.7.2.
Gerald
Gerald,
From the chip designers perspective, the ROM bootcode finds and starts another boot stage located on an attached memory or device. Both the SRM and the AM335X TRM tell us this – in a very detailed fashion in the case of the TRM.
The architecture of the BB, BBB and many other cards have split the external boot code into two layers, however – that would be Das Uboot and the SPL layer that loads it. This is transparent to the low level hardware documentation. So, the SRM and TRM would not have been appropriate resources to reference for the original post, as they do not address this now. The “boot order” referenced has only two stages, not three.
I will send you some suggestions for the SRM. I think only a few sentences would clarify things…
Thanks,
Don
I will work to add more detail.
Gerald