diff mbox series

[v2,3/8] clk: renesas: rcar-gen3: Avoid double table iteration in SD .set_rate()

Message ID 20190830134515.11925-4-geert+renesas@glider.be
State Mainlined
Commit e8adb3a0f74cf568030b7bd1f77d877e6f308d17
Delegated to: Geert Uytterhoeven
Headers show
Series clk: renesas: rcar-gen2/gen3: Switch to .determine_rate() | expand

Commit Message

Geert Uytterhoeven Aug. 30, 2019, 1:45 p.m. UTC
The .set_rate() callback for the SD clocks is always called with a valid
clock rate, returned by .round_rate().  Hence there is no need to
iterate through the divider table twice: once to repeat the work done by
.round_rate(), and a second time to find the corresponding divider
entry.

Just iterate once, looking for the divider that matches the passed clock
rate.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
v2:
  - No changes.
---
 drivers/clk/renesas/rcar-gen3-cpg.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Niklas Söderlund Aug. 30, 2019, 10:06 p.m. UTC | #1
Hi Geert,

Thanks for your patch.

On 2019-08-30 15:45:10 +0200, Geert Uytterhoeven wrote:
> The .set_rate() callback for the SD clocks is always called with a valid
> clock rate, returned by .round_rate().  Hence there is no need to
> iterate through the divider table twice: once to repeat the work done by
> .round_rate(), and a second time to find the corresponding divider
> entry.
> 
> Just iterate once, looking for the divider that matches the passed clock
> rate.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Clever :-)

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
> v2:
>   - No changes.
> ---
>  drivers/clk/renesas/rcar-gen3-cpg.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c
> index 3480284a08308134..9f457411984b1ca4 100644
> --- a/drivers/clk/renesas/rcar-gen3-cpg.c
> +++ b/drivers/clk/renesas/rcar-gen3-cpg.c
> @@ -339,14 +339,14 @@ static long cpg_sd_clock_round_rate(struct clk_hw *hw, unsigned long rate,
>  }
>  
>  static int cpg_sd_clock_set_rate(struct clk_hw *hw, unsigned long rate,
> -				   unsigned long parent_rate)
> +				 unsigned long parent_rate)
>  {
>  	struct sd_clock *clock = to_sd_clock(hw);
> -	unsigned int div = cpg_sd_clock_calc_div(clock, rate, parent_rate);
>  	unsigned int i;
>  
>  	for (i = 0; i < clock->div_num; i++)
> -		if (div == clock->div_table[i].div)
> +		if (rate == DIV_ROUND_CLOSEST(parent_rate,
> +					      clock->div_table[i].div))
>  			break;
>  
>  	if (i >= clock->div_num)
> -- 
> 2.17.1
>
diff mbox series

Patch

diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c
index 3480284a08308134..9f457411984b1ca4 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.c
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -339,14 +339,14 @@  static long cpg_sd_clock_round_rate(struct clk_hw *hw, unsigned long rate,
 }
 
 static int cpg_sd_clock_set_rate(struct clk_hw *hw, unsigned long rate,
-				   unsigned long parent_rate)
+				 unsigned long parent_rate)
 {
 	struct sd_clock *clock = to_sd_clock(hw);
-	unsigned int div = cpg_sd_clock_calc_div(clock, rate, parent_rate);
 	unsigned int i;
 
 	for (i = 0; i < clock->div_num; i++)
-		if (div == clock->div_table[i].div)
+		if (rate == DIV_ROUND_CLOSEST(parent_rate,
+					      clock->div_table[i].div))
 			break;
 
 	if (i >= clock->div_num)