[PATCH v3 3/5] ARM: dts: DRA7: Add TBCLK for PWMSS

Tero Kristo t-kristo at ti.com
Tue Mar 1 04:54:24 PST 2016


On 03/01/2016 01:23 AM, Tony Lindgren wrote:
> * Franklin S Cooper Jr <fcooper at ti.com> [160225 14:37]:
>> From: Vignesh R <vigneshr at ti.com>
>>
>> tbclk is used by ehrpwm to generate PWM waveform on DRA7 SoC. Add Linux
>> clock to control ehrpwm tbclk.
>> The TRM says, tbclk is derived from SYSCLKOUT. SYSCLKOUT is nothing but
>> ehrpwm functional clock derived from the gateable interface and
>> functional clock of PWMSS(l4_root_clk_div).
>> Refer AM57x TRM SPRUHZ6[1], October 2014, Table 29-4 and Section 29.2.2.1,
>> Table 29-19 and the NOTE at the end of the table.
>>
>> [1] www.ti.com/lit/ug/spruhz6/spruhz6.pdf
>
> Applying this into omap-for-v4.6/dt thanks.
>
> Note for Tero, let's plan on getting rid of the duplicate
> reg entries by using the standard clock output offset within
> the clock register. I think we should easily be able to add
> a binding for this and then deprecate the overlapping reg
> entries.

Yeah, we have been discussing this offline a bit, but haven't had time 
to look at this. I believe the hwmod clock conversion is of higher 
priority still.

-Tero


>
> Regards,
>
> Tony
>
>> --- a/arch/arm/boot/dts/dra7xx-clocks.dtsi
>> +++ b/arch/arm/boot/dts/dra7xx-clocks.dtsi
>> @@ -2146,4 +2146,28 @@
>>   		ti,bit-shift = <0>;
>>   		reg = <0x558>;
>>   	};
>> +
>> +       ehrpwm0_tbclk: ehrpwm0_tbclk {
>> +		#clock-cells = <0>;
>> +		compatible = "ti,gate-clock";
>> +		clocks = <&l4_root_clk_div>;
>> +		ti,bit-shift = <20>;
>> +		reg = <0x0558>;
>> +	};
>> +
>> +	ehrpwm1_tbclk: ehrpwm1_tbclk {
>> +		#clock-cells = <0>;
>> +		compatible = "ti,gate-clock";
>> +		clocks = <&l4_root_clk_div>;
>> +		ti,bit-shift = <21>;
>> +		reg = <0x0558>;
>> +	};
>> +
>> +	ehrpwm2_tbclk: ehrpwm2_tbclk {
>> +		#clock-cells = <0>;
>> +		compatible = "ti,gate-clock";
>> +		clocks = <&l4_root_clk_div>;
>> +		ti,bit-shift = <22>;
>> +		reg = <0x0558>;
>> +	};
>>   };
>> --
>> 2.7.0
>>




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