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 <grmoore@altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@altera.com>
Cc: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/socfpga/clk-pll.c b/drivers/clk/socfpga/clk-pll.c
index 362004e..834b6e9 100644
--- a/drivers/clk/socfpga/clk-pll.c
+++ b/drivers/clk/socfpga/clk-pll.c
@@ -44,7 +44,8 @@
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 @@
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 = {