Re: [PATCH v2] arm64: dts: qcom: sa8540p-ride: enable PCIe support

[Bjorn Andersson <andersson@kernel.org>]

On Thu, Dec 01, 2022 at 12:19:31PM -0500, Brian Masney wrote:
> Add the vreg_l11a, pcie3a, pcie3a_phy, and tlmm nodes that are necessary
> in order to get PCIe working on the QDrive3.
> 
> This patch also increases the width of the ranges property for the PCIe
> switch that's found on this platform. Note that this change requires
> the latest trustzone (TZ) firmware that's available from Qualcomm as
> of November 2022. If this is used against a board with the older
> firmware, then the board will go into ramdump mode when PCIe is probed
> on startup.
> 
> The ranges property is overridden in this sa8540p-ride.dts file since
> this is what's used to describe the QDrive3 variant with dual SoCs.
> There's another variant of this board that only has a single SoC where
> this change is not applicable, and hence why this specific change was
> not done in sa8540p.dtsi.
> 
> These changes were derived from various patches that Qualcomm
> delivered to Red Hat in a downstream kernel.
> 
> Signed-off-by: Brian Masney <bmasney@redhat.com>
> ---
> Changes since v1:
> - Add -state and -pins suffixes to tlmm (Krzysztof)
> 
> This patch depends on the following series that hasn't made it's way
> into linux-next yet:
> 
> [PATCH v10 0/2] arm64: dts: qcom: add dts for sa8540p-ride board
> https://lore.kernel.org/lkml/20221118025158.16902-1-quic_ppareek@quicinc.com/
> 
> I can't find the specific TZ firmware version that we have so that's why
> I included the date instead.
> 
>  arch/arm64/boot/dts/qcom/sa8540p-ride.dts | 54 +++++++++++++++++++++++
>  1 file changed, 54 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> index a5f87a8629d6..e953165f3b73 100644
> --- a/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> +++ b/arch/arm64/boot/dts/qcom/sa8540p-ride.dts
> @@ -51,6 +51,14 @@ vreg_l7a: ldo7 {
>  			regulator-initial-mode = <RPMH_REGULATOR_MODE_HPM>;
>  		};
>  
> +		vreg_l11a: ldo11 {
> +			regulator-name = "vreg_l11a";
> +			regulator-min-microvolt = <880000>;
> +			regulator-max-microvolt = <880000>;
> +			regulator-initial-mode = <RPMH_REGULATOR_MODE_HPM>;
> +			regulator-allow-set-load;

In order to specify regulator-allow-set-load you also need
regulator-allowed-modes.

But if I read the implementation correction, we don't actually alter the
load, so perhaps best to just omit this for now?

Regards,
Bjorn

> +		};
> +
>  		vreg_l13a: ldo13 {
>  			regulator-name = "vreg_l13a";
>  			regulator-min-microvolt = <3072000>;
> @@ -139,6 +147,27 @@ vreg_l8g: ldo8 {
>  	};
>  };
>  
> +&pcie3a {
> +	ranges = <0x01000000 0x0 0x32200000 0x0 0x32200000 0x0 0x100000>,
> +	         <0x02000000 0x0 0x40300000 0x0 0x40300000 0x0 0x20000000>,
> +	         <0x03000000 0x6 0x00000000 0x6 0x00000000 0x2 0x00000000>;
> +
> +	perst-gpios = <&tlmm 151 GPIO_ACTIVE_LOW>;
> +	wake-gpios = <&tlmm 56 GPIO_ACTIVE_HIGH>;
> +
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pcie3a_default>;
> +
> +	status = "okay";
> +};
> +
> +&pcie3a_phy {
> +	vdda-phy-supply = <&vreg_l11a>;
> +	vdda-pll-supply = <&vreg_l3a>;
> +
> +	status = "okay";
> +};
> +
>  &qup2 {
>  	status = "okay";
>  };
> @@ -158,6 +187,31 @@ &remoteproc_nsp1 {
>  	status = "okay";
>  };
>  
> +&tlmm {
> +	pcie3a_default: pcie3a-default-state {
> +		perst-pins {
> +			pins = "gpio151";
> +			function = "gpio";
> +			drive-strength = <2>;
> +			bias-pull-down;
> +		};
> +
> +		clkreq-pins {
> +			pins = "gpio150";
> +			function = "pcie3a_clkreq";
> +			drive-strength = <2>;
> +			bias-pull-up;
> +		};
> +
> +		wake-pins {
> +			pins = "gpio56";
> +			function = "gpio";
> +			drive-strength = <2>;
> +			bias-pull-up;
> +		};
> +	};
> +};
> +
>  &ufs_mem_hc {
>  	reset-gpios = <&tlmm 228 GPIO_ACTIVE_LOW>;
>  
> -- 
> 2.38.1
>