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Message-ID: <8a1f146a-d7e0-5ff3-1c7c-5fb1ee40e9c1@ti.com>
Date:   Mon, 5 Jun 2023 10:17:25 -0500
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Subject: Re: [PATCH 2/5] arm64: dts: ti: k3-j721e: Remove PCIe endpoint nodes
To:     "Verma, Achal" <a-verma1@ti.com>, Nishanth Menon <nm@ti.com>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Tero Kristo <kristo@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Robert Nelson <robertcnelson@gmail.com>
CC:     <linux-arm-kernel@lists.infradead.org>,
        <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>
References: <20230515172137.474626-1-afd@ti.com>
 <20230515172137.474626-2-afd@ti.com>
 <1de1328a-cfc9-d77c-eb11-3c341b46623b@ti.com>
 <4ff112d9-5c94-e7eb-8c94-4be769285a03@ti.com>
 <c42d0400-a5da-8883-a7ec-4d3c4d7ed71b@ti.com>
Content-Language: en-US
From:   Andrew Davis <afd@ti.com>
In-Reply-To: <c42d0400-a5da-8883-a7ec-4d3c4d7ed71b@ti.com>
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On 6/5/23 9:54 AM, Verma, Achal wrote:
> 
> 
> On 5/16/2023 9:57 PM, Andrew Davis wrote:
>> On 5/16/23 11:22 AM, Verma, Achal wrote:
>>>
>>>
>>> On 5/15/2023 10:51 PM, Andrew Davis wrote:
>>>> These nodes are example nodes for the PCIe controller in "endpoint" mode.
>>>> By default the controller is in "root complex" mode and there is already a
>>>> DT node for the same.
>>>>
>>>> Examples should go in the bindings or other documentation.
>>>>
>>>> Remove this node.
>>> How we will support EP from now onwards, using overlays ?
>>>
>>
>> They are already disabled, how do you support them today?
> As of now we edit the DTS (disable RC node and enable EP mode) but
> now we have to delete RC node and add EP node and build DTBS which
> looks like quite a work.
> 

I'd argue having to use a different node with a different compatible
to switch PCIe modes was not correct to begin with, it should have
been a property flag. Or even better, the modes should have been
switchable without modifying DTB at all.

Since it was chosen to put hardware configuration in DT, you'll have
to live with the problems that causes. My point it the same, examples
of how to do something do not belong in the DT files. Put the example
nodes in the documentation somewhere, then you can copy paste from that.

Andrew

> Regards,
> Achal Verma
> 
>>
>> Andrew
>>
>>> Regards,
>>> Achal Verma
>>>>
>>>> Signed-off-by: Andrew Davis <afd@ti.com>
>>>> ---
>>>>   .../boot/dts/ti/k3-j721e-beagleboneai64.dts   | 24 ------
>>>>   .../dts/ti/k3-j721e-common-proc-board.dts     | 25 ------
>>>>   arch/arm64/boot/dts/ti/k3-j721e-main.dtsi     | 82 -------------------
>>>>   arch/arm64/boot/dts/ti/k3-j721e-sk.dts        | 24 ------
>>>>   4 files changed, 155 deletions(-)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts b/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
>>>> index 8a62ac263b89..d77eeff0d81d 100644
>>>> --- a/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
>>>> +++ b/arch/arm64/boot/dts/ti/k3-j721e-beagleboneai64.dts
>>>> @@ -892,35 +892,11 @@ &pcie2_rc {
>>>>       status = "disabled";
>>>>   };
>>>> -&pcie0_ep {
>>>> -    status = "disabled";
>>>> -    phys = <&serdes0_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <1>;
>>>> -};
>>>> -
>>>> -&pcie1_ep {
>>>> -    status = "disabled";
>>>> -    phys = <&serdes1_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <2>;
>>>> -};
>>>> -
>>>> -&pcie2_ep {
>>>> -    /* Unused */
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &pcie3_rc {
>>>>       /* Unused */
>>>>       status = "disabled";
>>>>   };
>>>> -&pcie3_ep {
>>>> -    /* Unused */
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &icssg0_mdio {
>>>>       /* Unused */
>>>>       status = "disabled";
>>>> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-common-proc-board.dts b/arch/arm64/boot/dts/ti/k3-j721e-common-proc-board.dts
>>>> index 7db0603125aa..87b7263f6547 100644
>>>> --- a/arch/arm64/boot/dts/ti/k3-j721e-common-proc-board.dts
>>>> +++ b/arch/arm64/boot/dts/ti/k3-j721e-common-proc-board.dts
>>>> @@ -840,35 +840,10 @@ &pcie2_rc {
>>>>       num-lanes = <2>;
>>>>   };
>>>> -&pcie0_ep {
>>>> -    phys = <&serdes0_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <1>;
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>> -&pcie1_ep {
>>>> -    phys = <&serdes1_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <2>;
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>> -&pcie2_ep {
>>>> -    phys = <&serdes2_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <2>;
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &pcie3_rc {
>>>>       status = "disabled";
>>>>   };
>>>> -&pcie3_ep {
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &icssg0_mdio {
>>>>       status = "disabled";
>>>>   };
>>>> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi b/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
>>>> index 10c8a5fb4ee2..e39f6d1e8d40 100644
>>>> --- a/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
>>>> +++ b/arch/arm64/boot/dts/ti/k3-j721e-main.dtsi
>>>> @@ -816,26 +816,6 @@ pcie0_rc: pcie@2900000 {
>>>>           dma-ranges = <0x02000000 0x0 0x0 0x0 0x0 0x10000 0x0>;
>>>>       };
>>>> -    pcie0_ep: pcie-ep@2900000 {
>>>> -        compatible = "ti,j721e-pcie-ep";
>>>> -        reg = <0x00 0x02900000 0x00 0x1000>,
>>>> -              <0x00 0x02907000 0x00 0x400>,
>>>> -              <0x00 0x0d000000 0x00 0x00800000>,
>>>> -              <0x00 0x10000000 0x00 0x08000000>;
>>>> -        reg-names = "intd_cfg", "user_cfg", "reg", "mem";
>>>> -        interrupt-names = "link_state";
>>>> -        interrupts = <GIC_SPI 318 IRQ_TYPE_EDGE_RISING>;
>>>> -        ti,syscon-pcie-ctrl = <&scm_conf 0x4070>;
>>>> -        max-link-speed = <3>;
>>>> -        num-lanes = <2>;
>>>> -        power-domains = <&k3_pds 239 TI_SCI_PD_EXCLUSIVE>;
>>>> -        clocks = <&k3_clks 239 1>;
>>>> -        clock-names = "fck";
>>>> -        max-functions = /bits/ 8 <6>;
>>>> -        max-virtual-functions = /bits/ 8 <4 4 4 4 0 0>;
>>>> -        dma-coherent;
>>>> -    };
>>>> -
>>>>       pcie1_rc: pcie@2910000 {
>>>>           compatible = "ti,j721e-pcie-host";
>>>>           reg = <0x00 0x02910000 0x00 0x1000>,
>>>> @@ -864,26 +844,6 @@ pcie1_rc: pcie@2910000 {
>>>>           dma-ranges = <0x02000000 0x0 0x0 0x0 0x0 0x10000 0x0>;
>>>>       };
>>>> -    pcie1_ep: pcie-ep@2910000 {
>>>> -        compatible = "ti,j721e-pcie-ep";
>>>> -        reg = <0x00 0x02910000 0x00 0x1000>,
>>>> -              <0x00 0x02917000 0x00 0x400>,
>>>> -              <0x00 0x0d800000 0x00 0x00800000>,
>>>> -              <0x00 0x18000000 0x00 0x08000000>;
>>>> -        reg-names = "intd_cfg", "user_cfg", "reg", "mem";
>>>> -        interrupt-names = "link_state";
>>>> -        interrupts = <GIC_SPI 330 IRQ_TYPE_EDGE_RISING>;
>>>> -        ti,syscon-pcie-ctrl = <&scm_conf 0x4074>;
>>>> -        max-link-speed = <3>;
>>>> -        num-lanes = <2>;
>>>> -        power-domains = <&k3_pds 240 TI_SCI_PD_EXCLUSIVE>;
>>>> -        clocks = <&k3_clks 240 1>;
>>>> -        clock-names = "fck";
>>>> -        max-functions = /bits/ 8 <6>;
>>>> -        max-virtual-functions = /bits/ 8 <4 4 4 4 0 0>;
>>>> -        dma-coherent;
>>>> -    };
>>>> -
>>>>       pcie2_rc: pcie@2920000 {
>>>>           compatible = "ti,j721e-pcie-host";
>>>>           reg = <0x00 0x02920000 0x00 0x1000>,
>>>> @@ -912,26 +872,6 @@ pcie2_rc: pcie@2920000 {
>>>>           dma-ranges = <0x02000000 0x0 0x0 0x0 0x0 0x10000 0x0>;
>>>>       };
>>>> -    pcie2_ep: pcie-ep@2920000 {
>>>> -        compatible = "ti,j721e-pcie-ep";
>>>> -        reg = <0x00 0x02920000 0x00 0x1000>,
>>>> -              <0x00 0x02927000 0x00 0x400>,
>>>> -              <0x00 0x0e000000 0x00 0x00800000>,
>>>> -              <0x44 0x00000000 0x00 0x08000000>;
>>>> -        reg-names = "intd_cfg", "user_cfg", "reg", "mem";
>>>> -        interrupt-names = "link_state";
>>>> -        interrupts = <GIC_SPI 342 IRQ_TYPE_EDGE_RISING>;
>>>> -        ti,syscon-pcie-ctrl = <&scm_conf 0x4078>;
>>>> -        max-link-speed = <3>;
>>>> -        num-lanes = <2>;
>>>> -        power-domains = <&k3_pds 241 TI_SCI_PD_EXCLUSIVE>;
>>>> -        clocks = <&k3_clks 241 1>;
>>>> -        clock-names = "fck";
>>>> -        max-functions = /bits/ 8 <6>;
>>>> -        max-virtual-functions = /bits/ 8 <4 4 4 4 0 0>;
>>>> -        dma-coherent;
>>>> -    };
>>>> -
>>>>       pcie3_rc: pcie@2930000 {
>>>>           compatible = "ti,j721e-pcie-host";
>>>>           reg = <0x00 0x02930000 0x00 0x1000>,
>>>> @@ -960,28 +900,6 @@ pcie3_rc: pcie@2930000 {
>>>>           dma-ranges = <0x02000000 0x0 0x0 0x0 0x0 0x10000 0x0>;
>>>>       };
>>>> -    pcie3_ep: pcie-ep@2930000 {
>>>> -        compatible = "ti,j721e-pcie-ep";
>>>> -        reg = <0x00 0x02930000 0x00 0x1000>,
>>>> -              <0x00 0x02937000 0x00 0x400>,
>>>> -              <0x00 0x0e800000 0x00 0x00800000>,
>>>> -              <0x44 0x10000000 0x00 0x08000000>;
>>>> -        reg-names = "intd_cfg", "user_cfg", "reg", "mem";
>>>> -        interrupt-names = "link_state";
>>>> -        interrupts = <GIC_SPI 354 IRQ_TYPE_EDGE_RISING>;
>>>> -        ti,syscon-pcie-ctrl = <&scm_conf 0x407c>;
>>>> -        max-link-speed = <3>;
>>>> -        num-lanes = <2>;
>>>> -        power-domains = <&k3_pds 242 TI_SCI_PD_EXCLUSIVE>;
>>>> -        clocks = <&k3_clks 242 1>;
>>>> -        clock-names = "fck";
>>>> -        max-functions = /bits/ 8 <6>;
>>>> -        max-virtual-functions = /bits/ 8 <4 4 4 4 0 0>;
>>>> -        dma-coherent;
>>>> -        #address-cells = <2>;
>>>> -        #size-cells = <2>;
>>>> -    };
>>>> -
>>>>       serdes_wiz4: wiz@5050000 {
>>>>           compatible = "ti,am64-wiz-10g";
>>>>           #address-cells = <1>;
>>>> diff --git a/arch/arm64/boot/dts/ti/k3-j721e-sk.dts b/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
>>>> index f650a7fd66b4..07d3282a583b 100644
>>>> --- a/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
>>>> +++ b/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
>>>> @@ -896,35 +896,11 @@ &pcie2_rc {
>>>>       status = "disabled";
>>>>   };
>>>> -&pcie0_ep {
>>>> -    status = "disabled";
>>>> -    phys = <&serdes0_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <1>;
>>>> -};
>>>> -
>>>> -&pcie1_ep {
>>>> -    status = "disabled";
>>>> -    phys = <&serdes1_pcie_link>;
>>>> -    phy-names = "pcie-phy";
>>>> -    num-lanes = <2>;
>>>> -};
>>>> -
>>>> -&pcie2_ep {
>>>> -    /* Unused */
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &pcie3_rc {
>>>>       /* Unused */
>>>>       status = "disabled";
>>>>   };
>>>> -&pcie3_ep {
>>>> -    /* Unused */
>>>> -    status = "disabled";
>>>> -};
>>>> -
>>>>   &icssg0_mdio {
>>>>       status = "disabled";
>>>>   };