[...]
> +static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
> +             unsigned long *best_parent_rate)
> +{
> +     struct clk_divider *divider = to_clk_divider(hw);
> +     int i, bestdiv = 0;
> +     unsigned long parent_rate, best = 0, now, maxdiv;
> +
> +     if (!rate)
> +             rate = 1;
> +
> +     maxdiv = (1 << divider->width);
> +
> +     if (divider->flags & CLK_DIVIDER_ONE_BASED)
> +             maxdiv--;
> +
> +     if (!best_parent_rate) {
> +             parent_rate = __clk_get_rate(__clk_get_parent(hw->clk));
> +             bestdiv = DIV_ROUND_UP(parent_rate, rate);
> +             bestdiv = bestdiv == 0 ? 1 : bestdiv;
> +             bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
> +             return bestdiv;
> +     }
> +
> +     /*
> +      * The maximum divider we can use without overflowing
> +      * unsigned long in rate * i below
> +      */
> +     maxdiv = min(ULONG_MAX / rate, maxdiv);
> +
> +     for (i = 1; i <= maxdiv; i++) {
> +             parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
> +                             MULT_ROUND_UP(rate, i));
> +             now = parent_rate / i;
> +             if (now <= rate && now > best) {
> +                     bestdiv = i;
> +                     best = now;
> +                     *best_parent_rate = parent_rate;
Better add              if (now == rate)
                                break;
There may be more than one hit for (now == rate). We'd better select
smallest div, thus smallest parent_rate.

It's the same comment for v6, but not show stopper.

Thanks
Richard
> +             }
> +     }
> +
> +     if (!bestdiv) {
> +             bestdiv = (1 << divider->width);
> +             if (divider->flags & CLK_DIVIDER_ONE_BASED)
> +                     bestdiv--;
> +             *best_parent_rate = __clk_round_rate(__clk_get_parent(hw->clk), 
> 1);
> +     }
> +
> +     return bestdiv;
> +}
 

_______________________________________________
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev

Reply via email to