According to EHSET_v1.01.pdf description (http://testusb.com/EHHS.html), the USB physical certification test are from 2 sides. One test case is PC running USB-IF HSET utility as being USB host to test the target board being USB device; the other case is target board acting as USB host to initate test signals to a test fixture.
The principle of test modes supported are based on Vid/Pid pair during enumration by host whoever takes.
Apply the attached patch (I use r13.4.1 kernel_imx tree), then enable "FSL_USB_TEST_MODE" in kernel config, rebuild uImage to get the test modes support kernel.
Original Attachment has been moved to: 0001-ENGR00241582-MX6-USB-host-USB-host-certification-pat.patch.zip