STR_WRITE_4
STR_WRITE_4(this, BDPL, 0);
STR_WRITE_4(this, BDPU, 0);
STR_WRITE_4(this, BDPL, dmaaddr);
STR_WRITE_4(this, BDPU, PTR_UPPER32(dmaaddr));
STR_WRITE_4(this, CBL, this->bufsize);