From: Dinh Nguyen Date: Wed, 19 Feb 2014 21:11:10 +0000 (-0600) Subject: clk: socfpga: Fix integer overflow in clock calculation X-Git-Tag: v3.15-rc1~72^2~48 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=5585f7317573873f95c1bb7748322c62a6c3a919;p=linux.git clk: socfpga: Fix integer overflow in clock calculation Use 64-bit integer for calculating clock rate. Also use do_div for the 64-bit division. Signed-off-by: Graham Moore Signed-off-by: Dinh Nguyen Cc: Steffen Trumtrar Signed-off-by: Mike Turquette --- diff --git a/drivers/clk/socfpga/clk-pll.c b/drivers/clk/socfpga/clk-pll.c index 362004e1e6fe..834b6e961971 100644 --- a/drivers/clk/socfpga/clk-pll.c +++ b/drivers/clk/socfpga/clk-pll.c @@ -44,7 +44,8 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk, unsigned long parent_rate) { struct socfpga_pll *socfpgaclk = to_socfpga_clk(hwclk); - unsigned long divf, divq, vco_freq, reg; + unsigned long divf, divq, reg; + unsigned long long vco_freq; unsigned long bypass; reg = readl(socfpgaclk->hw.reg); @@ -54,8 +55,9 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hwclk, divf = (reg & SOCFPGA_PLL_DIVF_MASK) >> SOCFPGA_PLL_DIVF_SHIFT; divq = (reg & SOCFPGA_PLL_DIVQ_MASK) >> SOCFPGA_PLL_DIVQ_SHIFT; - vco_freq = parent_rate * (divf + 1); - return vco_freq / (1 + divq); + vco_freq = (unsigned long long)parent_rate * (divf + 1); + do_div(vco_freq, (1 + divq)); + return (unsigned long)vco_freq; } static struct clk_ops clk_pll_ops = {