clk: stratix10: use do_div() for 64-bit calculation

do_div() macro to perform u64 division and guards against overflow if
the result is too large for the unsigned long return type.

Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
Link: https://lkml.kernel.org/r/20200114160726.19771-1-dinguyen@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This commit is contained in:
Dinh Nguyen 2020-01-14 10:07:25 -06:00 committed by Stephen Boyd
parent bb6d3fb354
commit cc26ed7be4

View File

@ -39,7 +39,9 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk,
/* read VCO1 reg for numerator and denominator */
reg = readl(socfpgaclk->hw.reg);
refdiv = (reg & SOCFPGA_PLL_REFDIV_MASK) >> SOCFPGA_PLL_REFDIV_SHIFT;
vco_freq = (unsigned long long)parent_rate / refdiv;
vco_freq = parent_rate;
do_div(vco_freq, refdiv);
/* Read mdiv and fdiv from the fdbck register */
reg = readl(socfpgaclk->hw.reg + 0x4);