Good news everyone! I managed to mount a card on Garnet VM!

"Card emulation" (a.k.a. HostFS) support is in GarnetVM. However, and don't ask me why, GVM folks do not distribute "gras-client" ARM binary, a "GVM remote control" which is needed to actually mount a filesystem and set up the card emulation.

No need to worry! I used gras-client (and a few socat tunnels) on my x86 computer to do the job:

Wonder of wonders, the setting actually survives closing and relaunching GVM!


A few hints:
You can get GVM for x86 from the ACCESS website.
On the x86 side:
$ socat tcp-listen:34130 tcp-connect:tablet:12000
On the tablet side:
$ socat tcp-listen:12000 tcp-connect:localhost:34130
$ /usr/bin/gvm/gvm -G
(launch GVM with gras server enabled)

Now, to trick PC's gras-client into believing he is talking to a local gvm, just launch gvm on the PC too. It won't be able to open the 34130 port again, and gras-client will talk to the tablet's GVM instance instead.

So launch gras-client, and do "mountvol /media/mmc1"
(be careful; after every gras-client command the socat tunnel will need to be restarted)

Sorry for the possibly too short explanation, It's late and I'm tired.
Obligatory useless screenshot:



There's now an easier way for doing this!! Keep reading, it's just a few posts down.