Back at the GStreamer Conference 2012 in San Diego there was the interesting TI OMAP4 Wayland demo. The demo by Rob Clark of Texas Instruments showed Wayland running very well on the low-power ARM platform, which uses Imagination's PowerVR SGX graphics core. As said in the article, "[Texas Instruments] hopes to release this TI OMAP4 driver support under an "experimental" state in the near future [for running Wayland]." The OMAP4 display hardware itself is already backed by a KMS driver, OMAPDRM.
Now this morning when Rob Clark released his spinning cube demo for the KMS console, in the mailing list announcement he wrote, "I've tested this on i915 and on panda (with the hopefully-soon-to-be-released pvr gbm/kms support)." So here he publicly confirms that the PVR (PowerVR) GBM/KMS support will hopefully be released soon.
On an entirely separate matter, I recently heard how there almost was an open-source PowerVR graphics driver for Linux with the blessing of Imagination Technologies. This wasn't going to be some reverse-engineered community project but was to be supported by a hardware vendor (not TI) and with programming documentation (provided under NDA by Imagination) to the vendor for writing the open PowerVR SGX driver. Sadly though that particular project never ended up working out and the initiative since abandoned.