REGISTER_BLOCK_SHIFT
#define REGISTER_BLOCK(x) ((x & REGISTER_BLOCK_MASK) >> REGISTER_BLOCK_SHIFT)
#define REGS_FLAT (0 << REGISTER_BLOCK_SHIFT)
#define REGS_NORTH_SHARED (1 << REGISTER_BLOCK_SHIFT)
#define REGS_NORTH_PIPE_AND_PORT (2 << REGISTER_BLOCK_SHIFT)
#define REGS_NORTH_PLANE_CONTROL (3 << REGISTER_BLOCK_SHIFT)
#define REGS_SOUTH_SHARED (4 << REGISTER_BLOCK_SHIFT)
#define REGS_SOUTH_TRANSCODER_PORT (5 << REGISTER_BLOCK_SHIFT)