Message-ID: <b83a2c9e-481b-a15e-d4a4-d8d68ae084a7@ti.com>
Date:   Fri, 3 Mar 2023 14:00:21 +0530
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Subject: Re: [PATCH v12 3/8] arm64: dts: ti: k3-j721s2-mcu-wakeup: Add support
 of OSPI
Content-Language: en-US
From:   Ravi Gunasekaran <r-gunasekaran@ti.com>
To:     Andrew Davis <afd@ti.com>, <nm@ti.com>, <vigneshr@ti.com>,
        <kristo@kernel.org>, <robh+dt@kernel.org>,
        <krzysztof.kozlowski+dt@linaro.org>, <s-vadapalli@ti.com>,
        <vaishnav.a@ti.com>, Ravi Gunasekaran <r-gunasekaran@ti.com>
CC:     <linux-arm-kernel@lists.infradead.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230301091136.17862-1-r-gunasekaran@ti.com>
 <20230301091136.17862-4-r-gunasekaran@ti.com>
 <61fab807-42df-cc2c-51de-f54e9ea477c8@ti.com>
 <7843adf0-f883-280b-1d87-44010ceef767@ti.com>
In-Reply-To: <7843adf0-f883-280b-1d87-44010ceef767@ti.com>
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Andrew,

On 02/03/23 9:03 am, Ravi Gunasekaran wrote:
> 
> 
> On 01/03/23 9:27 pm, Andrew Davis wrote:
>> On 3/1/23 3:11 AM, Ravi Gunasekaran wrote:
>>> From: Aswath Govindraju <a-govindraju@ti.com>
>>>
>>> Add support for two instance of OSPI in J721S2 SoC.
>>>
>>> Reviewed-by: Vaishnav Achath <vaishnav.a@ti.com>
>>> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
>>> Signed-off-by: Matt Ranostay <mranostay@ti.com>
>>> Signed-off-by: Ravi Gunasekaran <r-gunasekaran@ti.com>
>>> ---

[...]

>>>
>>>   .../boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi     | 46 +++++++++++++++++++
>>>   1 file changed, 46 insertions(+)
>>>
>>> diff --git a/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi b/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
>>> index 0af242aa9816..ab3ce8be7216 100644
>>> --- a/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
>>> +++ b/arch/arm64/boot/dts/ti/k3-j721s2-mcu-wakeup.dtsi
>>> @@ -306,4 +306,50 @@
>>>               ti,cpts-periodic-outputs = <2>;
>>>           };
>>>       };
>>> +
>>> +    fss: bus@47000000 {
>>> +        compatible = "simple-bus";
>>> +        #address-cells = <2>;
>>> +        #size-cells = <2>;
>>> +        ranges = <0x00 0x47000000 0x00 0x47000000 0x00 0x00068400>,
>>> +             <0x05 0x00000000 0x05 0x00000000 0x01 0x00000000>,
>>> +             <0x07 0x00000000 0x07 0x00000000 0x01 0x00000000>;
>>> +
>>> +        status = "disabled";
>>
>> Since this node doesn't need pinmux, why is it default disabled? Same for
>> the other parent nodes in this series.
>>
>> Andrew
> 
> In this patch and others in this series, since child node is disabled,
> I thought of disabling the parent as well. And to later enable the
> parent node at the time when the child node needs to be enabled.
> 

Could you please provide your input on this?

If the preferred way is to keep the parent node enabled, then I will
do so. For the IPs added in this series, if the parent node needs additional
information such as pinmux, gpio, I will disable both parent and child.
And if only child node(s) need additional info, then I will keep the parent
enabled and children disabled. 

>>
>>> +
>>> +        ospi0: spi@47040000 {
>>> +            compatible = "ti,am654-ospi", "cdns,qspi-nor";
>>> +            reg = <0x00 0x47040000 0x00 0x100>,
>>> +                  <0x05 0x00000000 0x01 0x00000000>;
>>> +            interrupts = <GIC_SPI 840 IRQ_TYPE_LEVEL_HIGH>;
>>> +            cdns,fifo-depth = <256>;
>>> +            cdns,fifo-width = <4>;
>>> +            cdns,trigger-address = <0x0>;
>>> +            clocks = <&k3_clks 109 5>;
>>> +            assigned-clocks = <&k3_clks 109 5>;
>>> +            assigned-clock-parents = <&k3_clks 109 7>;
>>> +            assigned-clock-rates = <166666666>;
>>> +            power-domains = <&k3_pds 109 TI_SCI_PD_EXCLUSIVE>;
>>> +            #address-cells = <1>;
>>> +            #size-cells = <0>;
>>> +
>>> +            status = "disabled"; /* Needs pinmux */
>>> +        };
>>> +
>>> +        ospi1: spi@47050000 {
>>> +            compatible = "ti,am654-ospi", "cdns,qspi-nor";
>>> +            reg = <0x00 0x47050000 0x00 0x100>,
>>> +                  <0x07 0x00000000 0x01 0x00000000>;
>>> +            interrupts = <GIC_SPI 841 IRQ_TYPE_LEVEL_HIGH>;
>>> +            cdns,fifo-depth = <256>;
>>> +            cdns,fifo-width = <4>;
>>> +            cdns,trigger-address = <0x0>;
>>> +            clocks = <&k3_clks 110 5>;
>>> +            power-domains = <&k3_pds 110 TI_SCI_PD_EXCLUSIVE>;
>>> +            #address-cells = <1>;
>>> +            #size-cells = <0>;
>>> +
>>> +            status = "disabled"; /* Needs pinmux */
>>> +        };
>>> +    };
>>>   };
> 

-- 
Regards,
Ravi