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Re: How to make sure my plug boots from the USB flash-stick instead of the USB hard-disk?

Martin Michlmayr wrote:
If you look at bootcmd_usb you'll see something like "ext2load usb
0:1".  0:1 defines the device and partition.

Unfortunately, I don't know whether you can force any consistent
device naming in u-boot.  I suppose you could run:
 ext2load usb 0:1 ....
 ext2load usb 1:1 ....
and in some cases the first command would fail and then the second
would succeed (or the other way around).

It seems to be consistent in my experience --- it appears to do a depth-first traversal of the USB tree arranged by internal port number. Certainly, mine has no problem booting from one specific USB storage device on a USB tree with five.

However I have noticed that u-boot seems to be very picky about what USB devices it talks to. I have three different brands of USB key, and only one works (the others all cause u-boot to time out). I'm looking forward to when boot-from-SD works reliably, as that will allow me to avoid the issue completely.

(Doesn't Linux have a system call to allow kernel chain-loading? Would this allow a basic kernel to be loaded from flash that then invokes a kernel read from a file system elsewhere?)

David Given

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