Appendix: Error Codes

#define DXE_ERROR(a)       (MAX_BIT|MAX_BIT >> 2 | (a))

EFI_REQUEST_UNLOAD_IMAGE	DXE_ERROR (1)	If this value is returned by an EFI image, then the image should be unloaded.
EFI_NOT_AVAILABLE_YET	DXE_ERROR (2)	IF this value is returned by an API, it means the capability is not yet installed/available/ready to use.