[PATCH] arm: dts: dra7xx-clocks: Fix the l3 and l4 clock rates

Rajendra Nayak rnayak at ti.com
Thu Jul 3 01:34:02 PDT 2014


On Tuesday 27 May 2014 02:25 PM, Rajendra Nayak wrote:
> Without the patch:
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck # cat clk_rate
> 532000000
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck/l3_iclk_div # cat clk_rate
> 532000000
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck/l3_iclk_div/l4_root_clk_div # cat clk_rate
> 532000000
> 
> With the patch:
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck # cat clk_rate
> 532000000
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck/l3_iclk_div # cat clk_rate
> 266000000
> /debug/.../dpll_core_x2_ck/dpll_core_h12x2_ck/l3_iclk_div/l4_root_clk_div # cat clk_rate
> 133000000
> 
> The l3 clock derived from core DPLL is actually a divider clock,
> with the default divider set to 2. l4 then derived from l3 is a fixed factor
> clock, but the fixed divider is 2 and not 1. Which means the l3 clock is
> half of core DPLLs h12x2 and l4 is half of l3 (as seen with this patch)

Tero, this seems like is yet to be picked up. You see any issues with this that needs to be
addressed?

regards,
Rajendra

> 
> Signed-off-by: Rajendra Nayak <rnayak at ti.com>
> ---
>  arch/arm/boot/dts/dra7xx-clocks.dtsi |   10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/dra7xx-clocks.dtsi b/arch/arm/boot/dts/dra7xx-clocks.dtsi
> index cfb8fc7..a14c99b 100644
> --- a/arch/arm/boot/dts/dra7xx-clocks.dtsi
> +++ b/arch/arm/boot/dts/dra7xx-clocks.dtsi
> @@ -673,10 +673,12 @@
>  
>  	l3_iclk_div: l3_iclk_div {
>  		#clock-cells = <0>;
> -		compatible = "fixed-factor-clock";
> +		compatible = "ti,divider-clock";
> +		ti,max-div = <2>;
> +		ti,bit-shift = <4>;
> +		reg = <0x0100>;
>  		clocks = <&dpll_core_h12x2_ck>;
> -		clock-mult = <1>;
> -		clock-div = <1>;
> +		ti,index-power-of-two;
>  	};
>  
>  	l4_root_clk_div: l4_root_clk_div {
> @@ -684,7 +686,7 @@
>  		compatible = "fixed-factor-clock";
>  		clocks = <&l3_iclk_div>;
>  		clock-mult = <1>;
> -		clock-div = <1>;
> +		clock-div = <2>;
>  	};
>  
>  	video1_clk2_div: video1_clk2_div {
> 




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