clk: mmp: add init callback for clk-frac

For the clk-frac, we need to make sure that the initial
clock rate is one item of the table.
If it is not, we use the first item in the table by default.

Signed-off-by: Chao Xie <chao.xie@marvell.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

1 files changed, 40 insertions, 0 deletions

diff --git a/drivers/clk/mmp/clk-frac.c b/drivers/clk/mmp/clk-frac.c
index e29d006ab85e..1876d2c94bd3 100644
--- a/drivers/clk/mmp/clk-frac.c
+++ b/drivers/clk/mmp/clk-frac.c
@@ -118,10 +118,50 @@ static int clk_factor_set_rate(struct clk_hw *hw, unsigned long drate,
         return 0;
 }
 
+void clk_factor_init(struct clk_hw *hw)
+{
+        struct mmp_clk_factor *factor = to_clk_factor(hw);
+        struct mmp_clk_factor_masks *masks = factor->masks;
+        u32 val, num, den;
+        int i;
+        unsigned long flags = 0;
+
+        if (factor->lock)
+                spin_lock_irqsave(factor->lock, flags);
+
+        val = readl(factor->base);
+
+        /* calculate numerator */
+        num = (val >> masks->num_shift) & masks->num_mask;
+
+        /* calculate denominator */
+        den = (val >> masks->den_shift) & masks->den_mask;
+
+        for (i = 0; i < factor->ftbl_cnt; i++)
+                if (den == factor->ftbl[i].den && num == factor->ftbl[i].num)
+                        break;
+
+        if (i >= factor->ftbl_cnt) {
+                val &= ~(masks->num_mask << masks->num_shift);
+                val |= (factor->ftbl[0].num & masks->num_mask) <<
+                        masks->num_shift;
+
+                val &= ~(masks->den_mask << masks->den_shift);
+                val |= (factor->ftbl[0].den & masks->den_mask) <<
+                        masks->den_shift;
+
+                writel(val, factor->base);
+        }
+
+        if (factor->lock)
+                spin_unlock_irqrestore(factor->lock, flags);
+}
+
 static struct clk_ops clk_factor_ops = {
         .recalc_rate = clk_factor_recalc_rate,
         .round_rate = clk_factor_round_rate,
         .set_rate = clk_factor_set_rate,
+        .init = clk_factor_init,
 };
 
 struct clk *mmp_clk_register_factor(const char *name, const char *parent_name,