> I really have no idea where to go from here
you should start from here:
http://eewiki.net/display/linuxonarm/BeagleBone+Black
the stock kernel is compiled just using the instructions from the link
provided

Matt, I can help you with u-boot and kernel, at least just in removing
EEPROM check. What PHY do you use and what address is it?



2014-02-19 10:08 GMT+04:00 Matt <[email protected]>:

>
> Hey guys, I'm currently working on a project using a hardware replica of
> the Beaglebone Black, and I'm running into some issues with U-Boot and
> Device Trees. I haven't been involved with the hardware side of the board
> (which I'll affectionately call the Beagleclone from here on out) but I've
> been assured that the hardware is *identical *to what's on the BBB except
> for a changed Ethernet PHY and different headers and such.
>
> Right now the Beagleclone is booting from an SD card with both U-Boot
> (2013.04-dirty) and Angstrom Linux (v2012.12 with the 3.8.13 kernel) as
> they're packaged with the BBB. I've made various modifications to U-Boot
> while trying to prove some of this stuff out, but all of the information in
> my post is using the default BBB U-Boot/Angstrom files.
>
> When I boot the Beagleclone, U-Boot goes through its process without any
> major issues and Angstrom Linux starts. The problem is that I'd like to
> connect a simple TFT LCD display to the Beagleclone using the LCD pins on
> the AM335x. As far as I know this is possible, but the pins/driver need to
> be configured to make this happen. I've never worked with BBB before, but
> some quick research has indicated that Device Trees are the best way to
> implement this.
>
> The Beagleclone does not seem to have the Device Tree slots that are
> necessary to accomplish this. The documentation I've seen on Device Trees
> and the BBB (mostly this 
> guide<http://learn.adafruit.com/introduction-to-the-beaglebone-black-device-tree/overview>)
> suggest that there should be a /sys/devices/bone_capemgr*/slots file which
> stores the present Device Tree configuration and allows for modifications.
> Once my Beagleclone boots into Linux, I can navigate to the
> /sys/devices/bone_capemgr* directory, but there is no slots file in the
> directory. There are the normal subdirectories in the folder as well, with
> no directories for the specific slots entries, which makes sense given that
> the file doesn't exist. Since this file doesn't exist, I don't really know
> if it's possible to use Device Trees to change the hardware configuration.
>  I've also tried modifying uEnv.txt to add Device Trees while booting,
> but I haven't had any success with this either. Since I can't even get the
> slots file to show up I thought I'd try to tackle that first.
>
> Here's the serial output I get when booting the 
> Beagleclone<http://pastebin.com/ZBmatVgk>
>
> Since I have no experience with the BBB and I'm not all that familiar with
> U-Boot, the output linked above isn't exactly enlightening for me, but here
> are the main things I noticed:
>
> 1. U-Boot SPL fails to identify the Beagleclone as a BBB since its ID
> isn't stored in EEPROM. It seems like U-Boot immediately assumes that the
> board is a BBB and continues on. I'm not 100% sure that this isn't an
> issue, but I'd imagine an SPL failure would stop the system from booting
> into Linux so I doubt that this is causing the issue.
>
> 2. U-Boot also fails to identify the Beagleclone. There is no reassuring
> message this time about assuming the board is a BBB, but since SPL assumes
> I'm using "Black.musb-hdrc" and  U-boot refers to "musb-hdrc" after the
> ID failure, I'm going to guess that the assumption made by SPL carries over
> to the main U-Boot process.
>
> 3. The Ethernet PHY initialization fails. I'm using a different PHY with a
> different address from the BBB PHY so this isn't very surprising.
>
> 4. uEnv.txt is being read properly. I'm using the default BBB environment
> right now, but as I made modifications to uEnv.txt, this status output
> reflected the size of my modified uEnv.txt. I originally thought U-Boot
> might be ignoring my uEnv.txt file but it's definitely reading it even if
> its contents aren't doing anything when I change them.
>
> 5. When the kernel is booted, bone_capemgr throws a few errors because of
> the EEPROM ID failure. This seems like the most likely cause of my problem
> (since it involves bone_capemgr directly) but I'm not sure if this would
> stop me from using the slots file. U-Boot seems to be able to assume the
> Beagleclone is a BBB, but does the kernel *need *the ID to work? I could
> try writing the ID to EEPROM using U-Boot to accomplish this I guess, but
> I'm not sure what the ID is and where I should write it.
>
> 6. There are also some kernel errors regarding GPIO pinmuxing. I'll look
> into this later but I'm pretty confident that this isn't holding me back.
>
> That's all the information I have. I really have no idea where to go from
> here. As I said, I'm not experienced with any of this stuff so I'm really
> just hoping that somebody here can help me figure this out. If you need any
> more information just let me know. Thanks.
>
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