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Subject[PATCH] clk: tegra: Fix an infinite loop when clock rate is zero
Date
Calling clk_set_rate or clk_round_rate will lock up the kernel when the
rate is zero. This avoids the infinite loop and uses a slightly more
optimized p divider calculation.

Signed-off-by: ryang <decatf@gmail.com>
---
drivers/clk/tegra/clk-pll.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
index 830d1c87fa7c..17a058c3bbc1 100644
--- a/drivers/clk/tegra/clk-pll.c
+++ b/drivers/clk/tegra/clk-pll.c
@@ -582,9 +582,8 @@ static int _calc_rate(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
}

/* Raise VCO to guarantee 0.5% accuracy */
- for (cfg->output_rate = rate; cfg->output_rate < 200 * cfreq;
- cfg->output_rate <<= 1)
- p_div++;
+ p_div = rate ? fls((200 * cfreq) / rate) : 0;
+ cfg->output_rate = rate << p_div;

cfg->m = parent_rate / cfreq;
cfg->n = cfg->output_rate / cfreq;
--
2.17.1
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