Function nexus_map_resource

freebsd/x86/x86/nexus.c:478–534

}

static int
nexus_map_resource(device_t bus, device_t child, int type, struct resource *r,
    struct resource_map_request *argsp, struct resource_map *map)
{
	struct resource_map_request args;
	rman_res_t end, length, start;

	/* Resources must be active to be mapped. */
	if (!(rman_get_flags(r) & RF_ACTIVE))
		return (ENXIO);

	/* Mappings are only supported on I/O and memory resources. */
	switch (type) {
	case SYS_RES_IOPORT:
	case SYS_RES_MEMORY:
		break;
	default:
		return (EINVAL);
	}

	resource_init_map_request(&args);
	if (argsp != NULL)
		bcopy(argsp, &args, imin(argsp->size, args.size));
	start = rman_get_start(r) + args.offset;
	if (args.length == 0)
		length = rman_get_size(r);
	else
		length = args.length;
	end = start + length - 1;
	if (start > rman_get_end(r) || start < rman_get_start(r))
		return (EINVAL);
	if (end > rman_get_end(r) || end < start)
		return (EINVAL);

	/*
	 * If this is a memory resource, map it into the kernel.
	 */
	switch (type) {
	case SYS_RES_IOPORT:
		map->r_bushandle = start;
		map->r_bustag = X86_BUS_SPACE_IO;
		map->r_size = length;
		map->r_vaddr = NULL;
		break;
	case SYS_RES_MEMORY:
		map->r_vaddr = pmap_mapdev_attr(start, length, args.memattr);
		map->r_bustag = X86_BUS_SPACE_MEM;
		map->r_size = length;

		/*
		 * The handle is the virtual address.
		 */
		map->r_bushandle = (bus_space_handle_t)map->r_vaddr;
		break;
	}
	return (0);
}