HyperRAM
HyperRAM is used as an alternative to flash. Compared to flash, HyperRAM has similar performance but it avoids the need for a quad-speed SPI controller to interact with the flash. For details on the Windbond W956D8MBYA5I HyperRAM chip used on the Sonata board, see the datasheet. We anticipate mostly code to live in HyperRAM and to make sure that we don't suffer from access latency, we enable the instruction cache in Ibex.
Capability enabled RAM
Currently only 1 MiB of HyperRAM is accessible and all of that has associated capability tags, these tags are stored in 16 KiB of SRAM.