svc_mem device

This is a 3DO Portfolio OS device driver which mimic the internal device driver called raw which abstracts access to memory with custom read and write functions for accessing each type of memory (DRAM, VRAM, NVRAM, ROM, and memory mapped devices.)

The primary difference is that this library allows unfettered access to the hardware without any authorization checks. Meaning you can read the ROMS, read or write to NVRAM directly rather than through the filesystem, and interact with any memory mapped hardware like MADAM, CLIO, SPORT, etc.

While useful for interacting with the system the primary purpose it to demonstrate building a device driver with supervisor privileges. For general interaction with hardware it would probably be best to leverage a folio. The dispatch overhead will be lower than using the IO subsystem as device drivers do.

API

See the svc_mem.h header file and the read_rom and overwrite_folio_func examples in the 3do-devkit

Building

1. Get 3do-devkit
2. source 3do-devkit/activate-env
3. make
4. make install will install the header and library into 3do-devkit