Both the ram and rom interfaces are Simics internal, and should not be used by user-defined classes.
The phys_to_real_p function returns the page associated with the given address. get_page does the same thing but also returns the corresponding tag page in tags_ret.
typedef struct ram_interface { page_t *(*phys_to_real_p)(conf_object_t *obj, physical_address_t addr); page_t *(*get_page)(conf_object_t *obj, physical_address_t addr, page_t **tags_ret, unsigned *tag_ofs_ret); } ram_interface_t;
#define ROM_INTERFACE "rom"