I’ve just received a copy of the Marvell linux source tree (for their 4.4.52 kernel), and it includes an Inside Secure EIP97 driver.
I’ll guess it’s on its way towards mainline, as mainline already has an EIP197 driver from inside-secure (crypto_safexcel).
I can’t disclose any details as it’s covered by our NDA with Marvell, but as said, I would think it’s on its way into mainline.
I haven’t been able to find any patches publicly available, but since it is security/crypto, I don’t expect all patchwork to be publicized.
You can try and contact Inside Secure or Marvell for further information.