Commit db400ac1 authored by Martin Blumenstingl's avatar Martin Blumenstingl Committed by Stephen Boyd
Browse files

clk: divider: Switch from .round_rate to .determine_rate by default 



.determine_rate is meant to replace .round_rate. The former comes with a
benefit which is especially relevant on 32-bit systems: since
.determine_rate uses an "unsigned long" (compared to a "signed long"
which is used by .round_rate) the maximum value on 32-bit systems
increases from 2^31 (or approx. 2.14GHz) to 2^32 (or approx. 4.29GHz).
Switch to a .determine_rate implementation by default so 32-bit systems
can benefit from the increased maximum value as well as so we have one
fewer user of .round_rate.

Reviewed-by: default avatarJerome Brunet <jbrunet@baylibre.com>
Signed-off-by: default avatarMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20210627223959.188139-3-martin.blumenstingl@googlemail.com


Signed-off-by: default avatarStephen Boyd <sboyd@kernel.org>
parent bbd7a6cc

drivers/clk/clk-divider.c

+9 −9
Original line number Diff line number Diff line
@@ -425,8 +425,8 @@ long divider_ro_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, 
}

EXPORT_SYMBOL_GPL(divider_ro_round_rate_parent);



static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,

				unsigned long *prate)

static int clk_divider_determine_rate(struct clk_hw *hw,

				      struct clk_rate_request *req)

{

	struct clk_divider *divider = to_clk_divider(hw);
@@ -437,13 +437,13 @@ static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, 
		val = clk_div_readl(divider) >> divider->shift;

		val &= clk_div_mask(divider->width);



		return divider_ro_round_rate(hw, rate, prate, divider->table,

					     divider->width, divider->flags,

					     val);

		return divider_ro_determine_rate(hw, req, divider->table,

						 divider->width,

						 divider->flags, val);

	}



	return divider_round_rate(hw, rate, prate, divider->table,

				  divider->width, divider->flags);

	return divider_determine_rate(hw, req, divider->table, divider->width,

				      divider->flags);

}



int divider_get_val(unsigned long rate, unsigned long parent_rate,
@@ -500,14 +500,14 @@ static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate, 


const struct clk_ops clk_divider_ops = {

	.recalc_rate = clk_divider_recalc_rate,

	.round_rate = clk_divider_round_rate,

	.determine_rate = clk_divider_determine_rate,

	.set_rate = clk_divider_set_rate,

};

EXPORT_SYMBOL_GPL(clk_divider_ops);



const struct clk_ops clk_divider_ro_ops = {

	.recalc_rate = clk_divider_recalc_rate,

	.round_rate = clk_divider_round_rate,

	.determine_rate = clk_divider_determine_rate,

};

EXPORT_SYMBOL_GPL(clk_divider_ro_ops);