I've setup my Raspberry Pi as a kiosk, on a portrait-mounted HDMI TV.
display_rotate=1 and the GPU split to 128MB in
/boot/config.txt the screen is now the correct orientation.
However the bottom half of the screen is black. I know the desktop is extending the full height of the TV because the "Raspberry" background is in the middle of the screen, and windows fill beyond the edge of the drawn area.
The same is true for both the GUI and the terminal (even during boot). I'm stumped as to why this is happening, and I can't find anything online referring to this issue.
Anyone have any ideas?