Looking for qual core based Heterogeneous asymmetric mutlicore similar to i.MX 7 SoC

This line (FreeRTOS on the Cortex-M4 of a Colibri iMX7) for imx7 has dual core cortex A7. I am looking for SoC with qual core at speed > 1.5Ghz

We currently don’t have any products with quad core Cortex-A and additional Cortex-M cores. We are working on a new product, the Apalis iMX8 which will have all you need. It will be available in 2018. For more information please check the following product page:
https://www.toradex.com/computer-on-modules/apalis-arm-family/nxp-imx-8
On this page, you also find a link to subscribe to updates about this new product so you are always up to date on the progress and availability.