[PATCH V2 0/6] PCI: tegra: Enable PCIe C5 controller of Tegra194 in p2972-0000 platform

[PATCH V2 0/6] PCI: tegra: Enable PCIe C5 controller of Tegra194 in p2972-0000 platform

[Vidya Sagar]

This patch series enables Tegra194's C5 controller which owns x16 slot in
p2972-0000 platform. C5 controller's PERST# and CLKREQ# are not configured as
output and bi-directional signals by default and hence they need to be
configured explicitly. Also, x16 slot's 3.3V and 12V supplies are controlled
through GPIOs and hence they need to be enabled through regulator framework.
This patch series adds required infrastructural support to address both the
aforementioned requirements.
Testing done on p2972-0000 platform
- Able to enumerate devices connected to x16 slot (owned by C5 controller)
- Enumerated device's functionality verified
- Suspend-Resume sequence is verified with device connected to x16 slot

V2:
* Changed the order of patches in the series for easy merging
* Addressed review comments from Thierry Reding and Andrew Murray

Vidya Sagar (6):
  dt-bindings: PCI: tegra: Add sideband pins configuration entries
  dt-bindings: PCI: tegra: Add PCIe slot supplies regulator entries
  PCI: tegra: Add support to configure sideband pins
  PCI: tegra: Add support to enable slot regulators
  arm64: tegra: Add configuration for PCIe C5 sideband signals
  arm64: tegra: Add PCIe slot supply information in p2972-0000 platform

 .../bindings/pci/nvidia,tegra194-pcie.txt     | 16 ++++
 .../arm64/boot/dts/nvidia/tegra194-p2888.dtsi | 24 +++++
 .../boot/dts/nvidia/tegra194-p2972-0000.dts   |  4 +-
 arch/arm64/boot/dts/nvidia/tegra194.dtsi      | 38 +++++++-
 drivers/pci/controller/dwc/pcie-tegra194.c    | 91 ++++++++++++++++++-
 5 files changed, 169 insertions(+), 4 deletions(-)

-- 
2.17.1

[PATCH V2 1/6] dt-bindings: PCI: tegra: Add sideband pins configuration entries

[Vidya Sagar]

Add optional bindings "pinctrl-names" and "pinctrl-0" to describe pin
configuration information of a particular PCIe controller.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* None

 .../devicetree/bindings/pci/nvidia,tegra194-pcie.txt      | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
index 674e5adb2895..0ac1b867ac24 100644
--- a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
@@ -83,6 +83,11 @@ Required properties:
 - vddio-pex-ctl-supply: Regulator supply for PCIe side band signals
 
 Optional properties:
+- pinctrl-names: A list of pinctrl state names.
+  It is mandatory for C5 controller and optional for other controllers.
+  - "default": Configures PCIe I/O for proper operation.
+- pinctrl-0: phandle for the 'default' state of pin configuration.
+  It is mandatory for C5 controller and optional for other controllers.
 - supports-clkreq: Refer to Documentation/devicetree/bindings/pci/pci.txt
 - nvidia,update-fc-fixup: This is a boolean property and needs to be present to
     improve performance when a platform is designed in such a way that it
@@ -120,6 +125,9 @@ Tegra194:
 		num-lanes = <8>;
 		linux,pci-domain = <0>;
 
+		pinctrl-names = "default";
+		pinctrl-0 = <&pex_rst_c5_out_state>, <&clkreq_c5_bi_dir_state>;
+
 		clocks = <&bpmp TEGRA194_CLK_PEX0_CORE_0>;
 		clock-names = "core";
 
-- 
2.17.1

[PATCH V2 2/6] dt-bindings: PCI: tegra: Add PCIe slot supplies regulator entries

[Vidya Sagar]

Add optional bindings "vpcie3v3-supply" and "vpcie12v-supply" to describe
regulators of a PCIe slot's supplies 3.3V and 12V provided the platform
is designed to have regulator controlled slot supplies.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* None

 .../devicetree/bindings/pci/nvidia,tegra194-pcie.txt      | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
index 0ac1b867ac24..b739f92da58e 100644
--- a/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/nvidia,tegra194-pcie.txt
@@ -104,6 +104,12 @@ Optional properties:
    specified in microseconds
 - nvidia,aspm-l0s-entrance-latency-us: ASPM L0s entrance latency to be
    specified in microseconds
+- vpcie3v3-supply: A phandle to the regulator node that supplies 3.3V to the slot
+  if the platform has one such slot. (Ex:- x16 slot owned by C5 controller
+  in p2972-0000 platform).
+- vpcie12v-supply: A phandle to the regulator node that supplies 12V to the slot
+  if the platform has one such slot. (Ex:- x16 slot owned by C5 controller
+  in p2972-0000 platform).
 
 Examples:
 =========
@@ -156,6 +162,8 @@ Tegra194:
 			  0xc2000000 0x18 0x00000000 0x18 0x00000000 0x4 0x00000000>;  /* prefetchable memory (16GB) */
 
 		vddio-pex-ctl-supply = <&vdd_1v8ao>;
+		vpcie3v3-supply = <&vdd_3v3_pcie>;
+		vpcie12v-supply = <&vdd_12v_pcie>;
 
 		phys = <&p2u_hsio_2>, <&p2u_hsio_3>, <&p2u_hsio_4>,
 		       <&p2u_hsio_5>;
-- 
2.17.1

[PATCH V2 3/6] PCI: tegra: Add support to configure sideband pins

[Vidya Sagar]

Add support to configure sideband signal pins when information is present
in respective controller's device-tree node.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* Addressed review comment from Andrew Murray
* Handled failure case of pinctrl_pm_select_default_state() cleanly

 drivers/pci/controller/dwc/pcie-tegra194.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index fc0dbeb31d78..057ba4f9fbcd 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -1304,8 +1304,13 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
 	if (ret < 0) {
 		dev_err(dev, "Failed to get runtime sync for PCIe dev: %d\n",
 			ret);
-		pm_runtime_disable(dev);
-		return ret;
+		goto fail_pm_get_sync;
+	}
+
+	ret = pinctrl_pm_select_default_state(pcie->dev);
+	if (ret < 0) {
+		dev_err(dev, "Failed to configure sideband pins: %d\n", ret);
+		goto fail_pinctrl;
 	}
 
 	tegra_pcie_init_controller(pcie);
@@ -1332,7 +1337,9 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
 
 fail_host_init:
 	tegra_pcie_deinit_controller(pcie);
+fail_pinctrl:
 	pm_runtime_put_sync(dev);
+fail_pm_get_sync:
 	pm_runtime_disable(dev);
 	return ret;
 }
-- 
2.17.1

[PATCH V2 4/6] PCI: tegra: Add support to enable slot regulators

[Vidya Sagar]

Add support to get regulator information of 3.3V and 12V supplies of a PCIe
slot from the respective controller's device-tree node and enable those
supplies. This is required in platforms like p2972-0000 where the supplies
to x16 slot owned by C5 controller need to be enabled before attempting to
enumerate the devices.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* Addressed review comments from Thierry Reding and Andrew Murray
* Handled failure case of devm_regulator_get_optional() for -ENODEV cleanly

 drivers/pci/controller/dwc/pcie-tegra194.c | 80 ++++++++++++++++++++++
 1 file changed, 80 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index 057ba4f9fbcd..6a66101ec83d 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -278,6 +278,8 @@ struct tegra_pcie_dw {
 	u32 aspm_l0s_enter_lat;
 
 	struct regulator *pex_ctl_supply;
+	struct regulator *slot_ctl_3v3;
+	struct regulator *slot_ctl_12v;
 
 	unsigned int phy_count;
 	struct phy **phys;
@@ -1047,6 +1049,72 @@ static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
 	}
 }
 
+static int tegra_pcie_get_slot_regulators(struct tegra_pcie_dw *pcie)
+{
+	pcie->slot_ctl_3v3 = devm_regulator_get_optional(pcie->dev, "vpcie3v3");
+	if (IS_ERR(pcie->slot_ctl_3v3)) {
+		if (PTR_ERR(pcie->slot_ctl_3v3) != -ENODEV)
+			return PTR_ERR(pcie->slot_ctl_3v3);
+
+		pcie->slot_ctl_3v3 = NULL;
+	}
+
+	pcie->slot_ctl_12v = devm_regulator_get_optional(pcie->dev, "vpcie12v");
+	if (IS_ERR(pcie->slot_ctl_12v)) {
+		if (PTR_ERR(pcie->slot_ctl_12v) != -ENODEV)
+			return PTR_ERR(pcie->slot_ctl_12v);
+
+		pcie->slot_ctl_12v = NULL;
+	}
+
+	return 0;
+}
+
+static int tegra_pcie_enable_slot_regulators(struct tegra_pcie_dw *pcie)
+{
+	int ret;
+
+	if (pcie->slot_ctl_3v3) {
+		ret = regulator_enable(pcie->slot_ctl_3v3);
+		if (ret < 0) {
+			dev_err(pcie->dev,
+				"Failed to enable 3V3 slot supply: %d\n", ret);
+			return ret;
+		}
+	}
+
+	if (pcie->slot_ctl_12v) {
+		ret = regulator_enable(pcie->slot_ctl_12v);
+		if (ret < 0) {
+			dev_err(pcie->dev,
+				"Failed to enable 12V slot supply: %d\n", ret);
+			goto fail_12v_enable;
+		}
+	}
+
+	/*
+	 * According to PCI Express Card Electromechanical Specification
+	 * Revision 1.1, Table-2.4, T_PVPERL (Power stable to PERST# inactive)
+	 * should be a minimum of 100ms.
+	 */
+	msleep(100);
+
+	return 0;
+
+fail_12v_enable:
+	if (pcie->slot_ctl_3v3)
+		regulator_disable(pcie->slot_ctl_3v3);
+	return ret;
+}
+
+static void tegra_pcie_disable_slot_regulators(struct tegra_pcie_dw *pcie)
+{
+	if (pcie->slot_ctl_12v)
+		regulator_disable(pcie->slot_ctl_12v);
+	if (pcie->slot_ctl_3v3)
+		regulator_disable(pcie->slot_ctl_3v3);
+}
+
 static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
 					bool en_hw_hot_rst)
 {
@@ -1060,6 +1128,10 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
 		return ret;
 	}
 
+	ret = tegra_pcie_enable_slot_regulators(pcie);
+	if (ret < 0)
+		goto fail_slot_reg_en;
+
 	ret = regulator_enable(pcie->pex_ctl_supply);
 	if (ret < 0) {
 		dev_err(pcie->dev, "Failed to enable regulator: %d\n", ret);
@@ -1142,6 +1214,8 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
 fail_core_clk:
 	regulator_disable(pcie->pex_ctl_supply);
 fail_reg_en:
+	tegra_pcie_disable_slot_regulators(pcie);
+fail_slot_reg_en:
 	tegra_pcie_bpmp_set_ctrl_state(pcie, false);
 
 	return ret;
@@ -1174,6 +1248,8 @@ static int __deinit_controller(struct tegra_pcie_dw *pcie)
 		return ret;
 	}
 
+	tegra_pcie_disable_slot_regulators(pcie);
+
 	ret = tegra_pcie_bpmp_set_ctrl_state(pcie, false);
 	if (ret) {
 		dev_err(pcie->dev, "Failed to disable controller %d: %d\n",
@@ -1373,6 +1449,10 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	ret = tegra_pcie_get_slot_regulators(pcie);
+	if (ret < 0)
+		return ret;
+
 	pcie->pex_ctl_supply = devm_regulator_get(dev, "vddio-pex-ctl");
 	if (IS_ERR(pcie->pex_ctl_supply)) {
 		dev_err(dev, "Failed to get regulator: %ld\n",
-- 
2.17.1

[PATCH V2 5/6] arm64: tegra: Add configuration for PCIe C5 sideband signals

[Vidya Sagar]

Add support to configure PCIe C5's sideband signals PERST# and CLKREQ#
as output and bi-directional signals respectively which unlike other
PCIe controllers sideband signals are not configured by default.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* None

 arch/arm64/boot/dts/nvidia/tegra194.dtsi | 38 +++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra194.dtsi b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
index adebbbf36bd0..3c0cf54f0aab 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
@@ -3,8 +3,9 @@
 #include <dt-bindings/gpio/tegra194-gpio.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/mailbox/tegra186-hsp.h>
-#include <dt-bindings/reset/tegra194-reset.h>
+#include <dt-bindings/pinctrl/pinctrl-tegra.h>
 #include <dt-bindings/power/tegra194-powergate.h>
+#include <dt-bindings/reset/tegra194-reset.h>
 #include <dt-bindings/thermal/tegra194-bpmp-thermal.h>
 
 / {
@@ -130,6 +131,38 @@
 			};
 		};
 
+		pinmux: pinmux@2430000 {
+			compatible = "nvidia,tegra194-pinmux";
+			reg = <0x2430000 0x17000
+			       0xc300000 0x4000>;
+
+			status = "okay";
+
+			pex_rst_c5_out_state: pex_rst_c5_out {
+				pex_rst {
+					nvidia,pins = "pex_l5_rst_n_pgg1";
+					nvidia,schmitt = <TEGRA_PIN_DISABLE>;
+					nvidia,lpdr = <TEGRA_PIN_ENABLE>;
+					nvidia,enable-input = <TEGRA_PIN_DISABLE>;
+					nvidia,io-high-voltage = <TEGRA_PIN_ENABLE>;
+					nvidia,tristate = <TEGRA_PIN_DISABLE>;
+					nvidia,pull = <TEGRA_PIN_PULL_NONE>;
+				};
+			};
+
+			clkreq_c5_bi_dir_state: clkreq_c5_bi_dir {
+				clkreq {
+					nvidia,pins = "pex_l5_clkreq_n_pgg0";
+					nvidia,schmitt = <TEGRA_PIN_DISABLE>;
+					nvidia,lpdr = <TEGRA_PIN_ENABLE>;
+					nvidia,enable-input = <TEGRA_PIN_ENABLE>;
+					nvidia,io-high-voltage = <TEGRA_PIN_ENABLE>;
+					nvidia,tristate = <TEGRA_PIN_DISABLE>;
+					nvidia,pull = <TEGRA_PIN_PULL_NONE>;
+				};
+			};
+		};
+
 		uarta: serial@3100000 {
 			compatible = "nvidia,tegra194-uart", "nvidia,tegra20-uart";
 			reg = <0x03100000 0x40>;
@@ -1365,6 +1398,9 @@
 		num-viewport = <8>;
 		linux,pci-domain = <5>;
 
+		pinctrl-names = "default";
+		pinctrl-0 = <&pex_rst_c5_out_state>, <&clkreq_c5_bi_dir_state>;
+
 		clocks = <&bpmp TEGRA194_CLK_PEX1_CORE_5>,
 			<&bpmp TEGRA194_CLK_PEX1_CORE_5M>;
 		clock-names = "core", "core_m";
-- 
2.17.1

[PATCH V2 6/6] arm64: tegra: Add PCIe slot supply information in p2972-0000 platform

[Vidya Sagar]

Add 3.3V and 12V supplies regulators information of x16 PCIe slot in
p2972-0000 platform which is owned by C5 controller and also enable C5
controller.

Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
---
V2:
* None

 .../arm64/boot/dts/nvidia/tegra194-p2888.dtsi | 24 +++++++++++++++++++
 .../boot/dts/nvidia/tegra194-p2972-0000.dts   |  4 +++-
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
index 62e07e1197cc..4c38426a6969 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra194-p2888.dtsi
@@ -289,5 +289,29 @@
 			gpio = <&gpio TEGRA194_MAIN_GPIO(A, 3) GPIO_ACTIVE_HIGH>;
 			enable-active-high;
 		};
+
+		vdd_3v3_pcie: regulator@2 {
+			compatible = "regulator-fixed";
+			reg = <2>;
+
+			regulator-name = "PEX_3V3";
+			regulator-min-microvolt = <3300000>;
+			regulator-max-microvolt = <3300000>;
+			gpio = <&gpio TEGRA194_MAIN_GPIO(Z, 2) GPIO_ACTIVE_HIGH>;
+			regulator-boot-on;
+			enable-active-high;
+		};
+
+		vdd_12v_pcie: regulator@3 {
+			compatible = "regulator-fixed";
+			reg = <3>;
+
+			regulator-name = "VDD_12V";
+			regulator-min-microvolt = <1200000>;
+			regulator-max-microvolt = <1200000>;
+			gpio = <&gpio TEGRA194_MAIN_GPIO(A, 1) GPIO_ACTIVE_LOW>;
+			regulator-boot-on;
+			enable-active-low;
+		};
 	};
 };
diff --git a/arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts b/arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts
index 23597d53c9c9..d47cd8c4dd24 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts
+++ b/arch/arm64/boot/dts/nvidia/tegra194-p2972-0000.dts
@@ -93,9 +93,11 @@
 	};
 
 	pcie@141a0000 {
-		status = "disabled";
+		status = "okay";
 
 		vddio-pex-ctl-supply = <&vdd_1v8ao>;
+		vpcie3v3-supply = <&vdd_3v3_pcie>;
+		vpcie12v-supply = <&vdd_12v_pcie>;
 
 		phys = <&p2u_nvhs_0>, <&p2u_nvhs_1>, <&p2u_nvhs_2>,
 		       <&p2u_nvhs_3>, <&p2u_nvhs_4>, <&p2u_nvhs_5>,
-- 
2.17.1

Re: [PATCH V2 3/6] PCI: tegra: Add support to configure sideband pins

[Andrew Murray]

On Wed, Aug 28, 2019 at 06:45:02PM +0530, Vidya Sagar wrote:
> Add support to configure sideband signal pins when information is present
> in respective controller's device-tree node.
> 
> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> ---
> V2:
> * Addressed review comment from Andrew Murray
> * Handled failure case of pinctrl_pm_select_default_state() cleanly
> 
>  drivers/pci/controller/dwc/pcie-tegra194.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index fc0dbeb31d78..057ba4f9fbcd 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -1304,8 +1304,13 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
>  	if (ret < 0) {
>  		dev_err(dev, "Failed to get runtime sync for PCIe dev: %d\n",
>  			ret);
> -		pm_runtime_disable(dev);
> -		return ret;
> +		goto fail_pm_get_sync;
> +	}
> +
> +	ret = pinctrl_pm_select_default_state(pcie->dev);

This patch looks OK, though you're still using pcie->dev here instead of dev.

Thanks,

Andrew Murray

> +	if (ret < 0) {
> +		dev_err(dev, "Failed to configure sideband pins: %d\n", ret);
> +		goto fail_pinctrl;
>  	}
>  
>  	tegra_pcie_init_controller(pcie);
> @@ -1332,7 +1337,9 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
>  
>  fail_host_init:
>  	tegra_pcie_deinit_controller(pcie);
> +fail_pinctrl:
>  	pm_runtime_put_sync(dev);
> +fail_pm_get_sync:
>  	pm_runtime_disable(dev);
>  	return ret;
>  }
> -- 
> 2.17.1
> 

Re: [PATCH V2 4/6] PCI: tegra: Add support to enable slot regulators

[Andrew Murray]

On Wed, Aug 28, 2019 at 06:45:03PM +0530, Vidya Sagar wrote:
> Add support to get regulator information of 3.3V and 12V supplies of a PCIe
> slot from the respective controller's device-tree node and enable those
> supplies. This is required in platforms like p2972-0000 where the supplies
> to x16 slot owned by C5 controller need to be enabled before attempting to
> enumerate the devices.
> 
> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> ---
> V2:
> * Addressed review comments from Thierry Reding and Andrew Murray
> * Handled failure case of devm_regulator_get_optional() for -ENODEV cleanly
> 
>  drivers/pci/controller/dwc/pcie-tegra194.c | 80 ++++++++++++++++++++++
>  1 file changed, 80 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 057ba4f9fbcd..6a66101ec83d 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -278,6 +278,8 @@ struct tegra_pcie_dw {
>  	u32 aspm_l0s_enter_lat;
>  
>  	struct regulator *pex_ctl_supply;
> +	struct regulator *slot_ctl_3v3;
> +	struct regulator *slot_ctl_12v;
>  
>  	unsigned int phy_count;
>  	struct phy **phys;
> @@ -1047,6 +1049,72 @@ static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
>  	}
>  }
>  
> +static int tegra_pcie_get_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	pcie->slot_ctl_3v3 = devm_regulator_get_optional(pcie->dev, "vpcie3v3");
> +	if (IS_ERR(pcie->slot_ctl_3v3)) {
> +		if (PTR_ERR(pcie->slot_ctl_3v3) != -ENODEV)
> +			return PTR_ERR(pcie->slot_ctl_3v3);
> +
> +		pcie->slot_ctl_3v3 = NULL;
> +	}
> +
> +	pcie->slot_ctl_12v = devm_regulator_get_optional(pcie->dev, "vpcie12v");
> +	if (IS_ERR(pcie->slot_ctl_12v)) {
> +		if (PTR_ERR(pcie->slot_ctl_12v) != -ENODEV)
> +			return PTR_ERR(pcie->slot_ctl_12v);
> +
> +		pcie->slot_ctl_12v = NULL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tegra_pcie_enable_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	int ret;
> +
> +	if (pcie->slot_ctl_3v3) {
> +		ret = regulator_enable(pcie->slot_ctl_3v3);
> +		if (ret < 0) {
> +			dev_err(pcie->dev,
> +				"Failed to enable 3V3 slot supply: %d\n", ret);
> +			return ret;
> +		}
> +	}
> +
> +	if (pcie->slot_ctl_12v) {
> +		ret = regulator_enable(pcie->slot_ctl_12v);
> +		if (ret < 0) {
> +			dev_err(pcie->dev,
> +				"Failed to enable 12V slot supply: %d\n", ret);
> +			goto fail_12v_enable;
> +		}
> +	}
> +
> +	/*
> +	 * According to PCI Express Card Electromechanical Specification
> +	 * Revision 1.1, Table-2.4, T_PVPERL (Power stable to PERST# inactive)
> +	 * should be a minimum of 100ms.
> +	 */
> +	msleep(100);
> +
> +	return 0;
> +
> +fail_12v_enable:
> +	if (pcie->slot_ctl_3v3)
> +		regulator_disable(pcie->slot_ctl_3v3);
> +	return ret;
> +}
> +
> +static void tegra_pcie_disable_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	if (pcie->slot_ctl_12v)
> +		regulator_disable(pcie->slot_ctl_12v);
> +	if (pcie->slot_ctl_3v3)
> +		regulator_disable(pcie->slot_ctl_3v3);
> +}
> +
>  static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  					bool en_hw_hot_rst)
>  {
> @@ -1060,6 +1128,10 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  		return ret;
>  	}
>  
> +	ret = tegra_pcie_enable_slot_regulators(pcie);
> +	if (ret < 0)
> +		goto fail_slot_reg_en;
> +
>  	ret = regulator_enable(pcie->pex_ctl_supply);
>  	if (ret < 0) {
>  		dev_err(pcie->dev, "Failed to enable regulator: %d\n", ret);
> @@ -1142,6 +1214,8 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  fail_core_clk:
>  	regulator_disable(pcie->pex_ctl_supply);
>  fail_reg_en:
> +	tegra_pcie_disable_slot_regulators(pcie);
> +fail_slot_reg_en:
>  	tegra_pcie_bpmp_set_ctrl_state(pcie, false);
>  
>  	return ret;
> @@ -1174,6 +1248,8 @@ static int __deinit_controller(struct tegra_pcie_dw *pcie)
>  		return ret;
>  	}
>  
> +	tegra_pcie_disable_slot_regulators(pcie);
> +
>  	ret = tegra_pcie_bpmp_set_ctrl_state(pcie, false);
>  	if (ret) {
>  		dev_err(pcie->dev, "Failed to disable controller %d: %d\n",
> @@ -1373,6 +1449,10 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> +	ret = tegra_pcie_get_slot_regulators(pcie);
> +	if (ret < 0)
> +		return ret;

All of the functions called from tegra_pcie_dw_probe appear to dev_err if
something goes wrong, is there any reason why you haven't done that here?

Thanks,

Andrew Murray

> +
>  	pcie->pex_ctl_supply = devm_regulator_get(dev, "vddio-pex-ctl");
>  	if (IS_ERR(pcie->pex_ctl_supply)) {
>  		dev_err(dev, "Failed to get regulator: %ld\n",
> -- 
> 2.17.1
> 

Re: [PATCH V2 3/6] PCI: tegra: Add support to configure sideband pins

[Vidya Sagar]

On 8/28/2019 8:37 PM, Andrew Murray wrote:
> On Wed, Aug 28, 2019 at 06:45:02PM +0530, Vidya Sagar wrote:
>> Add support to configure sideband signal pins when information is present
>> in respective controller's device-tree node.
>>
>> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
>> ---
>> V2:
>> * Addressed review comment from Andrew Murray
>> * Handled failure case of pinctrl_pm_select_default_state() cleanly
>>
>>   drivers/pci/controller/dwc/pcie-tegra194.c | 11 +++++++++--
>>   1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
>> index fc0dbeb31d78..057ba4f9fbcd 100644
>> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
>> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
>> @@ -1304,8 +1304,13 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
>>   	if (ret < 0) {
>>   		dev_err(dev, "Failed to get runtime sync for PCIe dev: %d\n",
>>   			ret);
>> -		pm_runtime_disable(dev);
>> -		return ret;
>> +		goto fail_pm_get_sync;
>> +	}
>> +
>> +	ret = pinctrl_pm_select_default_state(pcie->dev);
> 
> This patch looks OK, though you're still using pcie->dev here instead of dev.
I'll take care of this.
Thanks for the thorough review.

- Vidya Sagar

> 
> Thanks,
> 
> Andrew Murray
> 
>> +	if (ret < 0) {
>> +		dev_err(dev, "Failed to configure sideband pins: %d\n", ret);
>> +		goto fail_pinctrl;
>>   	}
>>   
>>   	tegra_pcie_init_controller(pcie);
>> @@ -1332,7 +1337,9 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
>>   
>>   fail_host_init:
>>   	tegra_pcie_deinit_controller(pcie);
>> +fail_pinctrl:
>>   	pm_runtime_put_sync(dev);
>> +fail_pm_get_sync:
>>   	pm_runtime_disable(dev);
>>   	return ret;
>>   }
>> -- 
>> 2.17.1
>>

Re: [PATCH V2 4/6] PCI: tegra: Add support to enable slot regulators

[Thierry Reding]

[-- Attachment #1: Type: text/plain, Size: 4988 bytes --]

On Wed, Aug 28, 2019 at 06:45:03PM +0530, Vidya Sagar wrote:
> Add support to get regulator information of 3.3V and 12V supplies of a PCIe
> slot from the respective controller's device-tree node and enable those
> supplies. This is required in platforms like p2972-0000 where the supplies
> to x16 slot owned by C5 controller need to be enabled before attempting to
> enumerate the devices.
> 
> Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> ---
> V2:
> * Addressed review comments from Thierry Reding and Andrew Murray
> * Handled failure case of devm_regulator_get_optional() for -ENODEV cleanly
> 
>  drivers/pci/controller/dwc/pcie-tegra194.c | 80 ++++++++++++++++++++++
>  1 file changed, 80 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
> index 057ba4f9fbcd..6a66101ec83d 100644
> --- a/drivers/pci/controller/dwc/pcie-tegra194.c
> +++ b/drivers/pci/controller/dwc/pcie-tegra194.c
> @@ -278,6 +278,8 @@ struct tegra_pcie_dw {
>  	u32 aspm_l0s_enter_lat;
>  
>  	struct regulator *pex_ctl_supply;
> +	struct regulator *slot_ctl_3v3;
> +	struct regulator *slot_ctl_12v;
>  
>  	unsigned int phy_count;
>  	struct phy **phys;
> @@ -1047,6 +1049,72 @@ static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
>  	}
>  }
>  
> +static int tegra_pcie_get_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	pcie->slot_ctl_3v3 = devm_regulator_get_optional(pcie->dev, "vpcie3v3");
> +	if (IS_ERR(pcie->slot_ctl_3v3)) {
> +		if (PTR_ERR(pcie->slot_ctl_3v3) != -ENODEV)
> +			return PTR_ERR(pcie->slot_ctl_3v3);
> +
> +		pcie->slot_ctl_3v3 = NULL;
> +	}
> +
> +	pcie->slot_ctl_12v = devm_regulator_get_optional(pcie->dev, "vpcie12v");
> +	if (IS_ERR(pcie->slot_ctl_12v)) {
> +		if (PTR_ERR(pcie->slot_ctl_12v) != -ENODEV)
> +			return PTR_ERR(pcie->slot_ctl_12v);
> +
> +		pcie->slot_ctl_12v = NULL;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tegra_pcie_enable_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	int ret;
> +
> +	if (pcie->slot_ctl_3v3) {
> +		ret = regulator_enable(pcie->slot_ctl_3v3);
> +		if (ret < 0) {
> +			dev_err(pcie->dev,
> +				"Failed to enable 3V3 slot supply: %d\n", ret);

Nit: perhaps make this error message "Failed to enable 3.3V slot
supply"? Seems somewhat more user-friendly than 3V3.


> +			return ret;
> +		}
> +	}
> +
> +	if (pcie->slot_ctl_12v) {
> +		ret = regulator_enable(pcie->slot_ctl_12v);
> +		if (ret < 0) {
> +			dev_err(pcie->dev,
> +				"Failed to enable 12V slot supply: %d\n", ret);
> +			goto fail_12v_enable;
> +		}
> +	}
> +
> +	/*
> +	 * According to PCI Express Card Electromechanical Specification
> +	 * Revision 1.1, Table-2.4, T_PVPERL (Power stable to PERST# inactive)
> +	 * should be a minimum of 100ms.
> +	 */
> +	msleep(100);

Do you perhaps want to guard this with something like:

	if (pcie->slot_ctl_3v3 || pcie->slot_ctl_12v)

? Doesn't seem useful to me to sleep 100 ms here if there are no
regulators being enabled to begin with.

Thierry

> +
> +	return 0;
> +
> +fail_12v_enable:
> +	if (pcie->slot_ctl_3v3)
> +		regulator_disable(pcie->slot_ctl_3v3);
> +	return ret;
> +}
> +
> +static void tegra_pcie_disable_slot_regulators(struct tegra_pcie_dw *pcie)
> +{
> +	if (pcie->slot_ctl_12v)
> +		regulator_disable(pcie->slot_ctl_12v);
> +	if (pcie->slot_ctl_3v3)
> +		regulator_disable(pcie->slot_ctl_3v3);
> +}
> +
>  static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  					bool en_hw_hot_rst)
>  {
> @@ -1060,6 +1128,10 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  		return ret;
>  	}
>  
> +	ret = tegra_pcie_enable_slot_regulators(pcie);
> +	if (ret < 0)
> +		goto fail_slot_reg_en;
> +
>  	ret = regulator_enable(pcie->pex_ctl_supply);
>  	if (ret < 0) {
>  		dev_err(pcie->dev, "Failed to enable regulator: %d\n", ret);
> @@ -1142,6 +1214,8 @@ static int tegra_pcie_config_controller(struct tegra_pcie_dw *pcie,
>  fail_core_clk:
>  	regulator_disable(pcie->pex_ctl_supply);
>  fail_reg_en:
> +	tegra_pcie_disable_slot_regulators(pcie);
> +fail_slot_reg_en:
>  	tegra_pcie_bpmp_set_ctrl_state(pcie, false);
>  
>  	return ret;
> @@ -1174,6 +1248,8 @@ static int __deinit_controller(struct tegra_pcie_dw *pcie)
>  		return ret;
>  	}
>  
> +	tegra_pcie_disable_slot_regulators(pcie);
> +
>  	ret = tegra_pcie_bpmp_set_ctrl_state(pcie, false);
>  	if (ret) {
>  		dev_err(pcie->dev, "Failed to disable controller %d: %d\n",
> @@ -1373,6 +1449,10 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> +	ret = tegra_pcie_get_slot_regulators(pcie);
> +	if (ret < 0)
> +		return ret;
> +
>  	pcie->pex_ctl_supply = devm_regulator_get(dev, "vddio-pex-ctl");
>  	if (IS_ERR(pcie->pex_ctl_supply)) {
>  		dev_err(dev, "Failed to get regulator: %ld\n",
> -- 
> 2.17.1
> 

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