DMACtrl
dw32(DMACtrl, dr32(DMACtrl) | 0x00001000);
iowrite32(0x500, ioaddr + DMACtrl);
if ((ioread32(ioaddr + DMACtrl) & 0xc000) == 0)
iowrite32(0x80000000, ioaddr + DMACtrl);
iowrite32(0x80000000, ioaddr + DMACtrl);
iowrite32(dma_ctrl, ioaddr + DMACtrl);