VGA_MEM_BASE
vgatext = (uint16_t *)PTOV(VGA_MEM_BASE + VGA_MEM_SIZE);
to = (unsigned char *)ptov(VGA_MEM_BASE) + f_offset +
bus_space_map(sc->vga_fb_tag, VGA_MEM_BASE, VGA_MEM_SIZE, 0,
&res_id, VGA_MEM_BASE, VGA_MEM_BASE + VGA_MEM_SIZE - 1,