MGA_AR0
MGA_WRITE4(sc, MGA_AR0, (uint32_t)src_left);
MGA_WRITE4(sc, MGA_AR0, (uint32_t)src_right);
MGA_WRITE4(sc, MGA_AR0, (uint32_t)(font->fontwidth - 1));
MGA_WRITE4(sc, MGA_AR0, (uint32_t)(wi - 1));