| Message ID | 9c2f3ed66ae32e55721bfced41dfd70e49cb746c.1493812478.git-series.maxime.ripard@free-electrons.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, May 3, 2017 at 7:59 PM, Maxime Ripard <maxime.ripard@free-electrons.com> wrote: > So far, divider_round_rate only considers the parent clock returned by > clk_hw_get_parent. > > This works fine on clocks that have a single parents, this doesn't work on > muxes, since we will only consider the first parent, while other parents > may totally be able to provide a better combination. > > Clocks in that case cannot use divider_round_rate, so would have to come up > with a very similar logic to work around it. Instead of having to do > something like this, and duplicate that logic everywhere, create a > divider_round_rate parent to allow caller to give an additional parameter > for the parent clock to consider. > > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> > --- > drivers/clk/clk-divider.c | 26 ++++++++++++++++++-------- > include/linux/clk-provider.h | 4 ++++ > 2 files changed, 22 insertions(+), 8 deletions(-) > > diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c > index 96386ffc8483..48750439b1cd 100644 > --- a/drivers/clk/clk-divider.c > +++ b/drivers/clk/clk-divider.c > @@ -275,7 +275,8 @@ static int _next_div(const struct clk_div_table *table, int div, > return div; > } > > -static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, > +static int clk_divider_bestdiv(struct clk_hw *hw, struct clk_hw *parent, > + unsigned long rate, > unsigned long *best_parent_rate, > const struct clk_div_table *table, u8 width, > unsigned long flags) > @@ -314,8 +315,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, > *best_parent_rate = parent_rate_saved; > return i; > } > - parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), > - rate * i); > + parent_rate = clk_hw_round_rate(parent, rate * i); > now = DIV_ROUND_UP_ULL((u64)parent_rate, i); > if (_is_best_div(rate, now, best, flags)) { > bestdiv = i; > @@ -326,22 +326,32 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, > > if (!bestdiv) { > bestdiv = _get_maxdiv(table, width, flags); > - *best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), 1); > + *best_parent_rate = clk_hw_round_rate(parent, 1); > } > > return bestdiv; > } > > -long divider_round_rate(struct clk_hw *hw, unsigned long rate, > - unsigned long *prate, const struct clk_div_table *table, > - u8 width, unsigned long flags) > +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, > + unsigned long rate, unsigned long *prate, > + const struct clk_div_table *table, > + u8 width, unsigned long flags) > { > int div; > > - div = clk_divider_bestdiv(hw, rate, prate, table, width, flags); > + div = clk_divider_bestdiv(hw, parent, rate, prate, table, width, flags); > > return DIV_ROUND_UP_ULL((u64)*prate, div); > } > +EXPORT_SYMBOL_GPL(divider_round_rate_parent); > + > +long divider_round_rate(struct clk_hw *hw, unsigned long rate, > + unsigned long *prate, const struct clk_div_table *table, > + u8 width, unsigned long flags) > +{ > + return divider_round_rate_parent(hw, clk_hw_get_parent(hw), rate, prate, > + table, width, flags); > +} > EXPORT_SYMBOL_GPL(divider_round_rate); Could this be made a static inline instead? Otherwise, Reviewed-by: Chen-Yu Tsai <wens@csie.org> > > static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, > diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h > index a428aec36ace..14102f783f64 100644 > --- a/include/linux/clk-provider.h > +++ b/include/linux/clk-provider.h > @@ -412,6 +412,10 @@ extern const struct clk_ops clk_divider_ro_ops; > unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate, > unsigned int val, const struct clk_div_table *table, > unsigned long flags); > +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, > + unsigned long rate, unsigned long *prate, > + const struct clk_div_table *table, > + u8 width, unsigned long flags); > long divider_round_rate(struct clk_hw *hw, unsigned long rate, > unsigned long *prate, const struct clk_div_table *table, > u8 width, unsigned long flags); > -- > git-series 0.8.11
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index 96386ffc8483..48750439b1cd 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -275,7 +275,8 @@ static int _next_div(const struct clk_div_table *table, int div, return div; } -static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, +static int clk_divider_bestdiv(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *best_parent_rate, const struct clk_div_table *table, u8 width, unsigned long flags) @@ -314,8 +315,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, *best_parent_rate = parent_rate_saved; return i; } - parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), - rate * i); + parent_rate = clk_hw_round_rate(parent, rate * i); now = DIV_ROUND_UP_ULL((u64)parent_rate, i); if (_is_best_div(rate, now, best, flags)) { bestdiv = i; @@ -326,22 +326,32 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, if (!bestdiv) { bestdiv = _get_maxdiv(table, width, flags); - *best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), 1); + *best_parent_rate = clk_hw_round_rate(parent, 1); } return bestdiv; } -long divider_round_rate(struct clk_hw *hw, unsigned long rate, - unsigned long *prate, const struct clk_div_table *table, - u8 width, unsigned long flags) +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *prate, + const struct clk_div_table *table, + u8 width, unsigned long flags) { int div; - div = clk_divider_bestdiv(hw, rate, prate, table, width, flags); + div = clk_divider_bestdiv(hw, parent, rate, prate, table, width, flags); return DIV_ROUND_UP_ULL((u64)*prate, div); } +EXPORT_SYMBOL_GPL(divider_round_rate_parent); + +long divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate, const struct clk_div_table *table, + u8 width, unsigned long flags) +{ + return divider_round_rate_parent(hw, clk_hw_get_parent(hw), rate, prate, + table, width, flags); +} EXPORT_SYMBOL_GPL(divider_round_rate); static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index a428aec36ace..14102f783f64 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -412,6 +412,10 @@ extern const struct clk_ops clk_divider_ro_ops; unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate, unsigned int val, const struct clk_div_table *table, unsigned long flags); +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *prate, + const struct clk_div_table *table, + u8 width, unsigned long flags); long divider_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate, const struct clk_div_table *table, u8 width, unsigned long flags);
So far, divider_round_rate only considers the parent clock returned by clk_hw_get_parent. This works fine on clocks that have a single parents, this doesn't work on muxes, since we will only consider the first parent, while other parents may totally be able to provide a better combination. Clocks in that case cannot use divider_round_rate, so would have to come up with a very similar logic to work around it. Instead of having to do something like this, and duplicate that logic everywhere, create a divider_round_rate parent to allow caller to give an additional parameter for the parent clock to consider. Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com> --- drivers/clk/clk-divider.c | 26 ++++++++++++++++++-------- include/linux/clk-provider.h | 4 ++++ 2 files changed, 22 insertions(+), 8 deletions(-)