Re: [PATCH] ARM: dts: db600c: add support to pcie refclk

From: Bjorn Andersson
Date: Tue Mar 20 2018 - 23:35:21 EST


On Tue 20 Mar 17:28 HKT 2018, Srinivas Kandagatla wrote:

> From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
>
> This patch adds support to external pcie refclk.
>
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> ---
> 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