On Wed, May 3, 2017 at 7:59 PM, Maxime Ripard
<maxime.ripard@xxxxxxxxxxxxxxxxxx> wrote:
> Currently, the parent rate given back to the clock framework in our
> request is the original parent rate we calculated before trying to round
> the rate of our clock.
>
> This works fine unless our clock also changes its parent rate, in which
> case we will simply ignore that change and still use the previous parent
> rate.
>
> Create a new function to re-adjust the parent rate to take the pre-dividers
> into account, and give that back to the clock framework.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> ---
> drivers/clk/sunxi-ng/ccu_mux.c | 33 ++++++++++++++++++++++++++++-----
> 1 file changed, 28 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/clk/sunxi-ng/ccu_mux.c b/drivers/clk/sunxi-ng/ccu_mux.c
> index c33210972581..1ce62cc23f8a 100644
> --- a/drivers/clk/sunxi-ng/ccu_mux.c
> +++ b/drivers/clk/sunxi-ng/ccu_mux.c
> @@ -64,6 +64,14 @@ unsigned long ccu_mux_helper_apply_prediv(struct ccu_common *common,
> return parent_rate / ccu_mux_get_prediv(common, cm, parent_index);
> }
>
> +unsigned long ccu_mux_helper_unapply_prediv(struct ccu_common *common,
> + struct ccu_mux_internal *cm,
> + int parent_index,
> + unsigned long parent_rate)
> +{
> + return parent_rate * ccu_mux_get_prediv(common, cm, parent_index);
> +}
> +
> int ccu_mux_helper_determine_rate(struct ccu_common *common,
> struct ccu_mux_internal *cm,
> struct clk_rate_request *req,
> @@ -89,22 +97,37 @@ int ccu_mux_helper_determine_rate(struct ccu_common *common,
> best_rate = round(cm, best_parent, &adj_parent_rate,
> req->rate, data);
>
> + /*
> + * parent_rate might have been modified by our clock.
> + * Re-apply the pre-divider if there's one, and give
Might want to reword the comments to match the new name.
> + * the actual frequency the parent needs to run at.
> + */
> + best_parent_rate = ccu_mux_helper_unapply_prediv(common, cm, -1,
> + adj_parent_rate);
> +
> goto out;
> }
>
> for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
> - unsigned long tmp_rate, parent_rate, adj_parent_rate;
> + unsigned long tmp_rate, parent_rate;
> struct clk_hw *parent;
>
> parent = clk_hw_get_parent_by_index(hw, i);
> if (!parent)
> continue;
>
> - parent_rate = clk_hw_get_rate(parent);
> - adj_parent_rate = ccu_mux_helper_apply_prediv(common, cm, i,
> - parent_rate);
> + parent_rate = ccu_mux_helper_apply_prediv(common, cm, i,
> + clk_hw_get_rate(parent));
> +
> + tmp_rate = round(cm, parent, &parent_rate, req->rate, data);
>
> - tmp_rate = round(cm, parent, &adj_parent_rate, req->rate, data);
> + /*
> + * parent_rate might have been modified by our clock.
> + * Re-apply the pre-divider if there's one, and give
Same here. Otherwise,
Acked-by: Chen-Yu Tsai <wens@xxxxxxxx>
> + * the actual frequency the parent needs to run at.
> + */
> + parent_rate = ccu_mux_helper_unapply_prediv(common, cm, i,
> + parent_rate);
> if (tmp_rate == req->rate) {
> best_parent = parent;
> best_parent_rate = parent_rate;
> --
> git-series 0.8.11
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