SOCFPGA_PLL_REFDIV_SHIFT
arefdiv = (reg & SOCFPGA_PLL_AREFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;
refdiv = (reg & SOCFPGA_PLL_REFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;