gx1_gx_base
mc_regs = ioremap(gx1_gx_base() + 0x8400, 0x100);
unsigned gx1_gx_base(void);
gx_base = gx1_gx_base();
release_mem_region(gx1_gx_base() + 0x8300, 0x100);
release_mem_region(gx1_gx_base() + 0x8300, 0x100);