4.18-stable review patch. If anyone has any objections, please let me know.
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From: Ronald Wahl rwahl@gmx.de
commit 0f5cb0e6225cae2f029944cb8c74617aab6ddd49 upstream.
Commit a982e45dc150 ("clk: at91: PLL recalc_rate() now using cached MUL and DIV values") removed a check that prevents a division by zero. This now causes a stacktrace when booting the kernel on a at91 platform if the PLL DIV register contains zero. This commit reintroduces this check.
Fixes: a982e45dc150 ("clk: at91: PLL recalc_rate() now using cached...") Cc: stable@vger.kernel.org Signed-off-by: Ronald Wahl rwahl@gmx.de Acked-by: Ludovic Desroches ludovic.desroches@microchip.com Signed-off-by: Stephen Boyd sboyd@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/clk/at91/clk-pll.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/clk/at91/clk-pll.c +++ b/drivers/clk/at91/clk-pll.c @@ -133,6 +133,9 @@ static unsigned long clk_pll_recalc_rate { struct clk_pll *pll = to_clk_pll(hw);
+ if (!pll->div || !pll->mul) + return 0; + return (parent_rate / pll->div) * (pll->mul + 1); }