Alan:
Not sure if you got it to work, but the following worked for me.
I am using a BBB with
Linux beaglebone 3.8.13 #1 SMP Wed Sep 4 09:09:32 CEST 2013 armv7l GNU/Linux
I compiled your spi-test.c program and connected d0 to d1 and it ran perfectly.
root@beaglebone:~# ./BB-SPiTest
cmd: 0x02 0x12 0x34 0x56
rsp: 0x02 0x12 0x34 0x56
The main difference is that I used SPI0 instead of SPI1. I used the device tree overlay shown here:
http://elinux.org/BeagleBone_Black_Enable_SPIDEV
This web page shows how to use SPI1 first, and towards the end of the page shows the dts file for SPI0 (the one I tried). My guess is that you may still having some problems with the HDMI using those pins.
Martin