CR93
RegCR93 = viafb_read_reg(VIACR, CR93);
viafb_write_reg(CR93, VIACR, 0x01);
viafb_write_reg(CR93, VIACR, RegCR93);
viafb_write_reg_mask(CR93, VIACR, 0x21, BIT0 + BIT5);