SR18
unsigned char SR10, SR11, SR12, SR13, SR15, SR18, SR29, SR30;
reg->SR18 = 0x00;
vga_out8(0x3c5, reg->SR18, par);
reg->SR18 = vga_in8(0x3c5, par);
vga_out8(0x3c5, reg->SR18, par);
{IGA1_FIFO_HIGH_THRESHOLD_REG_NUM, {{SR18, 0, 5}, {SR18, 7, 7} } },
{VIASR, SR18, 0xFF, 0x4E},
{VIASR, SR18, 0xFF, 0x4E},
{VIASR, SR18, 0xFF, 0x4E},
{VIASR, SR18, 0xFF, 0x4E},
{VIASR, SR18, 0xFF, 0x4E},
{VIASR, SR18, 0xFF, 0x4E}, /* GFX PREQ threshold */