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Message-ID: <61296c69-c8c1-5aca-f471-cc0286b5bff3@quicinc.com>
Date:   Mon, 15 May 2023 15:07:30 +0530
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Subject: Re: [PATCH V3 5/6] arm64: dts: qcom: ipq9574: Enable PCIe PHYs and
 controllers
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To:     Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
CC:     <agross@kernel.org>, <andersson@kernel.org>,
        <konrad.dybcio@linaro.org>, <lpieralisi@kernel.org>,
        <kw@linux.com>, <robh@kernel.org>, <bhelgaas@google.com>,
        <krzysztof.kozlowski+dt@linaro.org>, <mturquette@baylibre.com>,
        <sboyd@kernel.org>, <mani@kernel.org>,
        <linux-arm-msm@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-pci@vger.kernel.org>,
        <linux-clk@vger.kernel.org>, <quic_srichara@quicinc.com>,
        <quic_sjaganat@quicinc.com>, <quic_kathirav@quicinc.com>,
        <quic_arajkuma@quicinc.com>, <quic_anusha@quicinc.com>,
        <quic_ipkumar@quicinc.com>
References: <20230421124938.21974-1-quic_devipriy@quicinc.com>
 <20230421124938.21974-6-quic_devipriy@quicinc.com>
 <CAA8EJpqx1jv_xEnS-2rOOGCtEB=1vo477H7XLGGvH=o7NHJD7w@mail.gmail.com>
 <6c962760-d81c-af52-bce2-49090f66f4ee@quicinc.com>
 <fdf697c1-16a3-6b8c-90fa-51ef7137d546@linaro.org>
From:   Devi Priya <quic_devipriy@quicinc.com>
In-Reply-To: <fdf697c1-16a3-6b8c-90fa-51ef7137d546@linaro.org>
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On 5/8/2023 5:09 PM, Dmitry Baryshkov wrote:
> On 08/05/2023 13:55, Devi Priya wrote:
>>
>>
>> On 4/22/2023 5:43 AM, Dmitry Baryshkov wrote:
>>> On Fri, 21 Apr 2023 at 15:51, Devi Priya <quic_devipriy@quicinc.com> 
>>> wrote:
>>>>
>>>> Enable the PCIe controller and PHY nodes corresponding to
>>>> RDP 433.
>>>>
>>>> Signed-off-by: Devi Priya <quic_devipriy@quicinc.com>
>>>> ---
>>>>   Changes in V3:
>>>>          - No change
>>>>
>>>>   arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts | 62 
>>>> +++++++++++++++++++++
>>>>   1 file changed, 62 insertions(+)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts 
>>>> b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
>>>> index 7be578017bf7..3ae38cf327ea 100644
>>>> --- a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
>>>> +++ b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
>>>> @@ -8,6 +8,7 @@
>>>>
>>>>   /dts-v1/;
>>>>
>>>> +#include <dt-bindings/gpio/gpio.h>
>>>>   #include "ipq9574.dtsi"
>>>>
>>>>   / {
>>>> @@ -43,6 +44,42 @@
>>>>          };
>>>>   };
>>>>
>>>> +&pcie1_phy {
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>> +&pcie1 {
>>>> +       pinctrl-names = "default";
>>>> +       pinctrl-0 = <&pcie_1_pin>;
>>>> +
>>>> +       perst-gpios = <&tlmm 26 GPIO_ACTIVE_LOW>;
>>>
>>> Usually qcom PCIe hosts also define wake-gpios.
>> In IPQ9574, we do not have hot plug support and host always starts the
>> enumeration for the device. Hence no wake pin is required.
> 
> None of the qcom PCIe hosts support hotplug, if I remember correctly. 
> This is not a reason not to describe the hardware.

Okay, will add the pin definitions for wake and clkreq in the next spin.
> 
>>>
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>> +&pcie2_phy {
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>> +&pcie2 {
>>>> +       pinctrl-names = "default";
>>>> +       pinctrl-0 = <&pcie_2_pin>;
>>>> +
>>>> +       perst-gpios = <&tlmm 29 GPIO_ACTIVE_LOW>;
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>> +&pcie3_phy {
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>> +&pcie3 {
>>>> +       pinctrl-names = "default";
>>>> +       pinctrl-0 = <&pcie_3_pin>;
>>>> +
>>>> +       perst-gpios = <&tlmm 32 GPIO_ACTIVE_LOW>;
>>>> +       status = "okay";
>>>> +};
>>>> +
>>>>   &sdhc_1 {
>>>>          pinctrl-0 = <&sdc_default_state>;
>>>>          pinctrl-names = "default";
>>>> @@ -60,6 +97,31 @@
>>>>   };
>>>>
>>>>   &tlmm {
>>>> +
>>>> +       pcie_1_pin: pcie-1-state {
>>>> +               pins = "gpio26";
>>>> +               function = "gpio";
>>>> +               drive-strength = <8>;
>>>> +               bias-pull-down;
>>>> +               output-low;
>>>
>>> No clkreq and no wake gpios?
>> We do not use any PCIe low power states and link is always in L0.
> 
> Again. We = software. Please describe the hardware here.
Got it.
> 
>>
>> Thanks,
>> Devi Priya
>>>
>>>> +       };
>>>> +
>>>> +       pcie_2_pin: pcie-2-state {
>>>> +               pins = "gpio29";
>>>> +               function = "gpio";
>>>> +               drive-strength = <8>;
>>>> +               bias-pull-down;
>>>> +               output-low;
>>>> +       };
>>>> +
>>>> +       pcie_3_pin: pcie-3-state {
>>>> +               pins = "gpio32";
>>>> +               function = "gpio";
>>>> +               drive-strength = <8>;
>>>> +               bias-pull-up;
>>>> +               output-low;
>>>> +       };
>>>> +
>>>>          sdc_default_state: sdc-default-state {
>>>>                  clk-pins {
>>>>                          pins = "gpio5";
>>>> -- 
>>>> 2.17.1
>>>>
>>>
>>>
> 
Thanks,
Devi Priya