DW_VR_CSR_VIEWPORT
writew(page, pxpcs->reg_base + (DW_VR_CSR_VIEWPORT << 1));
writel(page, pxpcs->reg_base + (DW_VR_CSR_VIEWPORT << 2));
writew(page, pxpcs->reg_base + (DW_VR_CSR_VIEWPORT << 1));
writel(page, pxpcs->reg_base + (DW_VR_CSR_VIEWPORT << 2));