diff options
| author | Doug Anderson <dianders@chromium.org> | 2013-06-11 19:24:05 +0400 |
|---|---|---|
| committer | Mike Turquette <mturquette@linaro.org> | 2013-06-11 20:51:26 +0400 |
| commit | 071ff9a36cb08b5a2b099fcdb45b63a61618f928 (patch) | |
| tree | aae3e0d37266606242ea6456ad09c43ffb5a7b2e /drivers/clk/samsung/clk-pll.c | |
| parent | 589c603b2c591ed470a731ceda589e6d60b77b5f (diff) | |
| download | linux-071ff9a36cb08b5a2b099fcdb45b63a61618f928.tar.xz | |
clk: samsung: Fix pll36xx_recalc_rate to handle kdiv properly
The KDIV value is often listed as unsigned but it needs to be treated
as a 16-bit signed value when using it in calculations. Fix our rate
recalculation to do this correctly.
Before doing this, I tried setting EPLL on exynos5250 to:
rate, m, p, s, k = 80000000, 107, 2, 4, 43691
This rate is exactly from the table in the exynos5250 user manual.
I read this back as 80750003 with:
cat /sys/kernel/debug/clk/fin_pll/fout_epll/clk_rate
After this patch, it reads back as 80000003
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Reviewed-by: Vikas Sajjan <vikas.sajjan@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk/samsung/clk-pll.c')
| -rw-r--r-- | drivers/clk/samsung/clk-pll.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index 89135f6be116..362f12dcd944 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c @@ -111,7 +111,8 @@ static unsigned long samsung_pll36xx_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct samsung_clk_pll36xx *pll = to_clk_pll36xx(hw); - u32 mdiv, pdiv, sdiv, kdiv, pll_con0, pll_con1; + u32 mdiv, pdiv, sdiv, pll_con0, pll_con1; + s16 kdiv; u64 fvco = parent_rate; pll_con0 = __raw_readl(pll->con_reg); @@ -119,7 +120,7 @@ static unsigned long samsung_pll36xx_recalc_rate(struct clk_hw *hw, mdiv = (pll_con0 >> PLL36XX_MDIV_SHIFT) & PLL36XX_MDIV_MASK; pdiv = (pll_con0 >> PLL36XX_PDIV_SHIFT) & PLL36XX_PDIV_MASK; sdiv = (pll_con0 >> PLL36XX_SDIV_SHIFT) & PLL36XX_SDIV_MASK; - kdiv = pll_con1 & PLL36XX_KDIV_MASK; + kdiv = (s16)(pll_con1 & PLL36XX_KDIV_MASK); fvco *= (mdiv << 16) + kdiv; do_div(fvco, (pdiv << sdiv)); |