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Message-ID: <9e3489f0-98f4-48ac-89a8-ea4ad3ee115c@ti.com>
Date:   Fri, 6 Oct 2023 17:22:35 +0530
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Subject: Re: [PATCH v7 5/7] arm64: dts: ti: k3-j784s4-mcu: Add the mcu domain
 watchdog instances
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To:     Nishanth Menon <nm@ti.com>
CC:     <robh+dt@kernel.org>, <vigneshr@ti.com>, <conor+dt@kernel.org>,
        <kristo@kernel.org>, <krzysztof.kozlowski+dt@linaro.org>,
        <u-kumar1@ti.com>, <linux-arm-kernel@lists.infradead.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20231006042901.6474-1-j-keerthy@ti.com>
 <20231006042901.6474-6-j-keerthy@ti.com>
 <20231006113410.tibvxxkeuujqnbv4@evolution>
From:   "J, KEERTHY" <j-keerthy@ti.com>
In-Reply-To: <20231006113410.tibvxxkeuujqnbv4@evolution>
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On 10/6/2023 5:04 PM, Nishanth Menon wrote:
> On 09:58-20231006, Keerthy wrote:
>> There are totally 2 instances of watchdog module in MCU domain.
>> These instances are coupled with the MCU domain R5F instances.
> 
>> Disabling them as they are not used by Linux.
> Device tree is hardware description - not tied to how Linux uses it.
> 
> Reason these wdts are disabled by default is because they are tightly
> coupled with R5Fs.
> 
>>
>> Signed-off-by: Keerthy <j-keerthy@ti.com>
>> ---
>>   .../boot/dts/ti/k3-j784s4-mcu-wakeup.dtsi     | 24 +++++++++++++++++++
>>   1 file changed, 24 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/ti/k3-j784s4-mcu-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-j784s4-mcu-wakeup.dtsi
>> index a7b5c4cb7d3e..809a0b1cf038 100644
>> --- a/arch/arm64/boot/dts/ti/k3-j784s4-mcu-wakeup.dtsi
>> +++ b/arch/arm64/boot/dts/ti/k3-j784s4-mcu-wakeup.dtsi
>> @@ -714,4 +714,28 @@
>>   		ti,esm-pins = <63>;
>>   		bootph-pre-ram;
>>   	};
>> +

Nishanth,

Below i have addressed the coupling with R5Fs & MCU domains watcdogs.

>> +	/*
>> +	 * The 2 RTI instances are couple with MCU R5Fs so keeping them
>> +	 * disabled as these will be used by their respective firmware
>> +	 */
>> +	mcu_watchdog0: watchdog@40600000 {
>> +		compatible = "ti,j7-rti-wdt";
>> +		reg = <0x00 0x40600000 0x00 0x100>;
>> +		clocks = <&k3_clks 367 1>;
>> +		power-domains = <&k3_pds 367 TI_SCI_PD_EXCLUSIVE>;
>> +		assigned-clocks = <&k3_clks 367 0>;
>> +		assigned-clock-parents = <&k3_clks 367 4>;
>> +		status = "disabled";
>> +	};
>> +
>> +	mcu_watchdog1: watchdog@40610000 {
>> +		compatible = "ti,j7-rti-wdt";
>> +		reg = <0x00 0x40610000 0x00 0x100>;
>> +		clocks = <&k3_clks 368 1>;
>> +		power-domains = <&k3_pds 368 TI_SCI_PD_EXCLUSIVE>;
>> +		assigned-clocks = <&k3_clks 368 0>;
>> +		assigned-clock-parents = <&k3_clks 368 4>;
> 
> Please DONOT ignore the review comments - I did ask the documentation in
> dts as well. reason being that this is what people will see rather than
> dig up the commit log. it should be intutive when reading the dts why
> nodes are disabled by default Vs the standard of leaving it enabled by
> default. Given esp that these peripherals do not have anything to do
> with board semantics (pinmux or something similar) to be complete.

As mentioned above. I added single comment for addressing both the 
watchdogs.

- Keerthy
> 
>> +		status = "disabled";
>> +	};
>>   };
>> -- 
>> 2.17.1
>>
>