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This is not a question, just a note to anyone else that has hardware with the USB data lines reversed.
When I set SYSBOOT bit 16 "DP/DM swapping" and set SYSBOOT 0:4 set to 0x10, I could boot fine with a USB stick inserted, or from NAND if a stick was absent. That's great.
Now if I set SYSBOOT 0:4 to 0x00 for a primary NAND boot and I booted from NAND, leaving SYSBOOT 16 set, UBoot and Linux would not recognize the USB (i.e., UBoot "usb reset" returned "Device not responding to set address" and couldn't find the USB stick, and Linux didn't create /dev/sda).
The problem is that SYSBOOT bit 16 does not get set in the CTRL_USB_CTRL register unless you have SYSBOOT 0:4 setup for USB boot. Further, there seems to be no way in UBoot to invert the data lines. To get around it, I added the following to the function usb_phy_power in drivers/usb/phy/omap_usb_phy.c
#ifdef CONFIG_INVERT_USB
val |= 0x00800000;
and added the corresponding CONFIG_INVERT_USB to the UBoot configuration file. Now UBoot and Linux are happy even with SYSBOOT 0:4 set to 0x00.
The bottom line is that setting SYSBOOT bit 16 is not enough to make UBoot and LInux aware that the USB data lines are inverted.
