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.rip...@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);
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
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
