This PR configures the BL808 MMU to cache the the User Text, Data and Heap. We enable the T-Head MMU Flags for Shareable, Bufferable and Cacheable, as explained in the previous PR: https://github.com/apache/nuttx/pull/13199
This PR fixes the Slow Memory Access for NuttX Apps on Ox64 BL808 SBC: https://github.com/apache/nuttx/issues/12696. With this fix, Ox64 NuttX CoreMark jumps from 19 to 1,104. (Close to Buildroot Linux CoreMark)
Modified Files:
`arch/risc-v/Kconfig`: Enabled `ARCH_MMU_EXT_THEAD` for BL808 SoC.