NV_CIO_CR_VRE_INDEX
regp->CRTC[NV_CIO_CR_VRE_INDEX] = 1 << 5 | XLATE(vertEnd, 0, NV_CIO_CR_VRE_3_0);
uint8_t cr11 = NVReadVgaCrtc(dev, head, NV_CIO_CR_VRE_INDEX);
NVWriteVgaCrtc(dev, head, NV_CIO_CR_VRE_INDEX, cr11);