VX_DMA
unsigned long port = vx2_reg_addr(chip, VX_DMA);
unsigned long port = vx2_reg_addr(chip, VX_DMA);
[VX_DMA] = 0x10,
[VX_DMA] = 1,
[VX_DMA] = 0x04, // DMA
long port = vxp_reg_addr(chip, VX_DMA);
long port = vxp_reg_addr(chip, VX_DMA);