Before I go cranking away, has anyone got sample code to use the second USB port (the serial debug port) as a regular-old-USB-port-#2? Can it even be done? I'd think so... would like to use it to drive a second HD or possibly a display.
It looks like this is related to the actual SATA-USB chipset on the drive enclosure (it's a JMicron unit). Substituted a PATA-USB enclosure with a Prolific Technology bridge and it's booted perfectly every time. I'll still dig into what's going on with the former as time permits.
If I boot from flash, I see the drive (/dev/sda1, /dev/sda2) every time; no problems there. The issue is getting u-boot to see the disk so I can boot from _it_. I also throttled back the USB drive to 1.5G and it got a little more reliable in the scan, but still no partitions visible, thus I'm thinking a timing issue in the USB device discovery routine ("usb start" sometimes sees the device, sometimes times out, sometimes hangs). I'm direct-connect, no external hub (though I'd love to use one), and power is external in a USB - to - SATA frame, so it's not a power issue..
I think I'll need to crack open the u-boot code and see if there's any way to tweak up the scan routines...
It'd be great to _reliably_ boot this puppy from a SATA / USB hard drive. I can seem to get it recognized about 1 out of 8 or 9 tries.... but have never been able to get fatload to work. As a matter of fact, even if I can see the drive in "usb info" and set it with "usb dev", "usb part" doesn't show any partitions, though if I boot from flash, fdisk shows a FAT12 and an ext3 partition. Any ideas?