nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x80000000);
nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl);
nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x00010000);
nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x80000000);
nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl);
nv_wr32(dev, NV50_AUXCH_CTRL(index), ctrl | 0x00010000);