diff mbox

ARM: dts: db600c: add support to pcie refclk

Message ID 20180320092840.4600-1-srinivas.kandagatla@linaro.org (mailing list archive)
State Changes Requested, archived
Headers show

Commit Message

Srinivas Kandagatla March 20, 2018, 9:28 a.m. UTC
From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

This patch adds support to external pcie refclk.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 arch/arm/boot/dts/qcom-apq8064-db600c.dts | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

Comments

Bjorn Andersson March 21, 2018, 3:35 a.m. UTC | #1
On Tue 20 Mar 17:28 HKT 2018, Srinivas Kandagatla wrote:

> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> 
> This patch adds support to external pcie refclk.
> 
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
>  arch/arm/boot/dts/qcom-apq8064-db600c.dts | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/qcom-apq8064-db600c.dts b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
> index 50151ef6e912..7587088c122f 100644
> --- a/arch/arm/boot/dts/qcom-apq8064-db600c.dts
> +++ b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
> @@ -45,6 +45,18 @@
>  
>  	};
>  
> +	clocks {
> +		compatible = "simple-bus";
> +		pcie_refclk: pcie-refclk {

As the si53154 is used to acquire 3 different clocks (2 pcie and 1 sata)
it would be nice to accurately represent this in the DT. That said,
exposing this as a clock allow us to change the representation here
later. (Both pcie_core_clk and pcie_eth_clk use the same gpio pin as
enable pin, so I don't know how to represent this...)

So for now, please name this "pcie_core_clk", per the schematics.

> +			pinctrl-0 = <&pcie_pins>;
> +			pinctrl-names = "default";
> +			compatible = "gpio-gate-clock";
> +	                clocks = <&rpmcc 27>;
> +			#clock-cells = <0>;
> +			enable-gpios = <&pm8921_gpio 22 GPIO_ACTIVE_HIGH>;
> +		};
> +	};
> +
>  	hdmi-out {
>  		compatible = "hdmi-connector";
>  		type = "a";
> @@ -140,6 +152,16 @@
>  
>  		qcom,ssbi@500000 {
>  			pmic@0 {
> +				gpio@150 {
> +					pcie_pins: pcie_pins {

Please label this "pcie_clk_en_pin" and don't use '_' in the name of the
node.

> +						pios {

You can omit this level and just put the properties in directly in the
pcie-clk-en node.

> +							pins = "gpio22";
> +							function = "normal";
> +							power-source = <PM8921_GPIO_VPH>;
> +						};
> +					};
> +				};
> +

Regards,
Bjorn
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Srinivas Kandagatla March 21, 2018, 5:26 a.m. UTC | #2
Thanks Bjorn for the review comments,

On 21/03/18 11:35, Bjorn Andersson wrote:
> On Tue 20 Mar 17:28 HKT 2018, Srinivas Kandagatla wrote:
> 
>> From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>>
>> This patch adds support to external pcie refclk.
>>
>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>> ---
>>   arch/arm/boot/dts/qcom-apq8064-db600c.dts | 27 +++++++++++++++++++++++++++
>>   1 file changed, 27 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/qcom-apq8064-db600c.dts b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
>> index 50151ef6e912..7587088c122f 100644
>> --- a/arch/arm/boot/dts/qcom-apq8064-db600c.dts
>> +++ b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
>> @@ -45,6 +45,18 @@
>>   
>>   	};
>>   
>> +	clocks {
>> +		compatible = "simple-bus";
>> +		pcie_refclk: pcie-refclk {
> 
> As the si53154 is used to acquire 3 different clocks (2 pcie and 1 sata)
> it would be nice to accurately represent this in the DT. That said,
> exposing this as a clock allow us to change the representation here
> later. (Both pcie_core_clk and pcie_eth_clk use the same gpio pin as
> enable pin, so I don't know how to represent this...)
> 
This is a refclk, which should be always same for both PCIe Controllers 
and connected PCIe endpoints.

For sata we should have one more refclk entry of its own.

> So for now, please name this "pcie_core_clk", per the schematics.

This is pcie refclk, if you follow the line in the schematics should see 
that it terminates to pcie refclk.

> 
>> +			pinctrl-0 = <&pcie_pins>;
>> +			pinctrl-names = "default";
>> +			compatible = "gpio-gate-clock";
>> +	                clocks = <&rpmcc 27>;
>> +			#clock-cells = <0>;
>> +			enable-gpios = <&pm8921_gpio 22 GPIO_ACTIVE_HIGH>;
>> +		};
>> +	};
>> +
>>   	hdmi-out {
>>   		compatible = "hdmi-connector";
>>   		type = "a";
>> @@ -140,6 +152,16 @@
>>   
>>   		qcom,ssbi@500000 {
>>   			pmic@0 {
>> +				gpio@150 {
>> +					pcie_pins: pcie_pins {
> 
> Please label this "pcie_clk_en_pin" and don't use '_' in the name of the
> node.
> 
I agree, Will fix it.
>> +						pios {
> 
> You can omit this level and just put the properties in directly in the
> pcie-clk-en node.
Okay.

thanks,
srini
> 
>> +							pins = "gpio22";
>> +							function = "normal";
>> +							power-source = <PM8921_GPIO_VPH>;
>> +						};
>> +					};
>> +				};
>> +
> 
> Regards,
> Bjorn
> 
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diff mbox

Patch

diff --git a/arch/arm/boot/dts/qcom-apq8064-db600c.dts b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
index 50151ef6e912..7587088c122f 100644
--- a/arch/arm/boot/dts/qcom-apq8064-db600c.dts
+++ b/arch/arm/boot/dts/qcom-apq8064-db600c.dts
@@ -45,6 +45,18 @@ 
 
 	};
 
+	clocks {
+		compatible = "simple-bus";
+		pcie_refclk: pcie-refclk {
+			pinctrl-0 = <&pcie_pins>;
+			pinctrl-names = "default";
+			compatible = "gpio-gate-clock";
+	                clocks = <&rpmcc 27>;
+			#clock-cells = <0>;
+			enable-gpios = <&pm8921_gpio 22 GPIO_ACTIVE_HIGH>;
+		};
+	};
+
 	hdmi-out {
 		compatible = "hdmi-connector";
 		type = "a";
@@ -140,6 +152,16 @@ 
 
 		qcom,ssbi@500000 {
 			pmic@0 {
+				gpio@150 {
+					pcie_pins: pcie_pins {
+						pios {
+							pins = "gpio22";
+							function = "normal";
+							power-source = <PM8921_GPIO_VPH>;
+						};
+					};
+				};
+
 				mpps@50 {
 					pcie_perst: pcie-perst {
 						pinconf {
@@ -439,6 +461,11 @@ 
 			pinctrl-0 = <&pcie_perst>;
 			pinctrl-names = "default";
 			perst-gpio = <&pm8921_mpps 1 GPIO_ACTIVE_LOW>;
+			clocks = <&gcc PCIE_A_CLK>,
+				 <&gcc PCIE_H_CLK>,
+				 <&gcc PCIE_PHY_REF_CLK>,
+				 <&pcie_refclk>;
+			clock-names = "core", "iface", "phy", "ref";
 		};
 
 		/* OTG */