[PATCH v1 0/3] PCI: qcom: Add support for OPP

[PATCH v1 0/3] PCI: qcom: Add support for OPP

[Krishna chaitanya chundru]

This patch adds support for OPP to vote for the performance state of RPMH
power domain based upon GEN speed it PCIe got enumerated.

Before link up PCIe driver will vote for the maximum performance state.

Krishna chaitanya chundru (3):
  dt-bindings: pci: qcom: Add binding for operating-points-v2
  arm64: dts: qcom: sm8450: Add opp table support to PCIe
  PCI: qcom: Add OPP suuport for speed based performance state of RPMH

 .../devicetree/bindings/pci/qcom,pcie.yaml         |  2 +
 arch/arm64/boot/dts/qcom/sm8450.dtsi               | 47 +++++++++++++++++
 drivers/pci/controller/dwc/pcie-qcom.c             | 61 ++++++++++++++++++++++
 3 files changed, 110 insertions(+)

-- 
2.7.4

[PATCH v1 1/3] dt-bindings: pci: qcom: Add binding for operating-points-v2

[Krishna chaitanya chundru]

This adds a binding documenting operating-points-v2.
Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
 Documentation/devicetree/bindings/pci/qcom,pcie.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
index 81971be4..6bc99c5 100644
--- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
+++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
@@ -121,6 +121,8 @@ properties:
     description: GPIO controlled connection to WAKE# signal
     maxItems: 1
 
+  operating-points-v2: true
+
 required:
   - compatible
   - reg
-- 
2.7.4

[PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Krishna chaitanya chundru]

PCIe needs to choose the appropriate performance state of RPMH power
domain based upon the PCIe gen speed.

So, let's add the OPP table support to specify RPMH performance states.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
 arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
index 595533a..681ea9c 100644
--- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
@@ -381,6 +381,49 @@
 		};
 	};
 
+	pcie0_opp_table: opp-table-pcie0 {
+		compatible = "operating-points-v2";
+
+		opp-2500000 {
+			opp-hz = /bits/ 64 <2500000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+
+		opp-5000000 {
+			opp-hz = /bits/ 64 <5000000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+
+		opp-8000000 {
+			opp-hz = /bits/ 64 <8000000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+	};
+
+	pcie1_opp_table: opp-table-pcie1 {
+		compatible = "operating-points-v2";
+
+		opp-2500000 {
+			opp-hz = /bits/ 64 <2500000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+
+		opp-5000000 {
+			opp-hz = /bits/ 64 <5000000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+
+		opp-8000000 {
+			opp-hz = /bits/ 64 <8000000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
+		};
+
+		opp-16000000 {
+			opp-hz = /bits/ 64 <16000000>;
+			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
+		};
+	};
+
 	reserved_memory: reserved-memory {
 		#address-cells = <2>;
 		#size-cells = <2>;
@@ -1803,6 +1846,8 @@
 			pinctrl-names = "default";
 			pinctrl-0 = <&pcie0_default_state>;
 
+			operating-points-v2 = <&pcie0_opp_table>;
+
 			status = "disabled";
 		};
 
@@ -1915,6 +1960,8 @@
 			pinctrl-names = "default";
 			pinctrl-0 = <&pcie1_default_state>;
 
+			operating-points-v2 = <&pcie1_opp_table>;
+
 			status = "disabled";
 		};
 
-- 
2.7.4

[PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH

[Krishna chaitanya chundru]

Before link training vote for the maximum performance state of RPMH
and once the link is up, vote for the performance state based upon
the link speed.
Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
 drivers/pci/controller/dwc/pcie-qcom.c | 61 ++++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 7a87a47..e29a986 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -22,6 +22,7 @@
 #include <linux/of_device.h>
 #include <linux/of_gpio.h>
 #include <linux/pci.h>
+#include <linux/pm_opp.h>
 #include <linux/pm_runtime.h>
 #include <linux/platform_device.h>
 #include <linux/phy/pcie.h>
@@ -1357,6 +1358,51 @@ static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
 	return 0;
 }
 
+static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
+{
+	struct dw_pcie *pci = pcie->pci;
+	struct dev_pm_opp *opp;
+	u32 offset, status;
+	uint32_t freq;
+	int speed;
+	int ret = 0;
+
+	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
+	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
+
+	/* Only update constraints if link is up. */
+	if (!(status & PCI_EXP_LNKSTA_DLLLA))
+		return;
+
+	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
+
+	switch (speed) {
+	case 1:
+		freq = 2500000;
+		break;
+	case 2:
+		freq = 5000000;
+		break;
+	case 3:
+		freq = 8000000;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		fallthrough;
+	case 4:
+		freq = 16000000;
+		break;
+	}
+
+	opp = dev_pm_opp_find_freq_exact(pci->dev, freq, true);
+
+	if (!IS_ERR(opp)) {
+		ret = dev_pm_opp_get_voltage(opp);
+		dev_pm_opp_put(opp);
+	}
+
+}
+
 static void qcom_pcie_icc_update(struct qcom_pcie *pcie)
 {
 	struct dw_pcie *pci = pcie->pci;
@@ -1439,8 +1485,10 @@ static void qcom_pcie_init_debugfs(struct qcom_pcie *pcie)
 static int qcom_pcie_probe(struct platform_device *pdev)
 {
 	const struct qcom_pcie_cfg *pcie_cfg;
+	unsigned long max_freq = INT_MAX;
 	struct device *dev = &pdev->dev;
 	struct qcom_pcie *pcie;
+	struct dev_pm_opp *opp;
 	struct dw_pcie_rp *pp;
 	struct resource *res;
 	struct dw_pcie *pci;
@@ -1511,6 +1559,17 @@ static int qcom_pcie_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_pm_runtime_put;
 
+	/* OPP table is optional */
+	ret = devm_pm_opp_of_add_table(dev);
+	if (ret && ret != -ENODEV) {
+		dev_err(dev, "Invalid OPP table in Device tree\n");
+		goto err_pm_runtime_put;
+	}
+
+	opp = dev_pm_opp_find_freq_floor(dev, &max_freq);
+	if (!IS_ERR(opp))
+		dev_pm_opp_put(opp);
+
 	ret = pcie->cfg->ops->get_resources(pcie);
 	if (ret)
 		goto err_pm_runtime_put;
@@ -1531,6 +1590,8 @@ static int qcom_pcie_probe(struct platform_device *pdev)
 
 	qcom_pcie_icc_update(pcie);
 
+	qcom_pcie_opp_update(pcie);
+
 	if (pcie->mhi)
 		qcom_pcie_init_debugfs(pcie);
 
-- 
2.7.4

Re: [PATCH v1 1/3] dt-bindings: pci: qcom: Add binding for operating-points-v2

[Krzysztof Kozlowski]

On 15/08/2023 14:26, Krishna chaitanya chundru wrote:
> This adds a binding documenting operating-points-v2.

1. Missing blank line. Don't write patches by yourself, but use tools
which create proper commit automatically. Every decent editor does it.

2. Please do not use "This commit/patch", but imperative mood. See
longer explanation here:
https://elixir.bootlin.com/linux/v5.17.1/source/Documentation/process/submitting-patches.rst#L95

3. A nit, subject: drop second/last, redundant "binding for". The
"dt-bindings" prefix is already stating that these are bindings.


> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  Documentation/devicetree/bindings/pci/qcom,pcie.yaml | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
> index 81971be4..6bc99c5 100644
> --- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
> @@ -121,6 +121,8 @@ properties:
>      description: GPIO controlled connection to WAKE# signal
>      maxItems: 1
>  
> +  operating-points-v2: true

phandle without actual table (opp-table) is rather meaningless.

Best regards,
Krzysztof

Re: [PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Krzysztof Kozlowski]

On 15/08/2023 14:26, Krishna chaitanya chundru wrote:
> PCIe needs to choose the appropriate performance state of RPMH power
> domain based upon the PCIe gen speed.

This explanation should be also in bindings patch, otherwise why would
we consider the bindings patch?

> 
> So, let's add the OPP table support to specify RPMH performance states.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> index 595533a..681ea9c 100644
> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> @@ -381,6 +381,49 @@
>  		};
>  	};
>  
> +	pcie0_opp_table: opp-table-pcie0 {
> +		compatible = "operating-points-v2";
> +
> +		opp-2500000 {
> +			opp-hz = /bits/ 64 <2500000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-5000000 {
> +			opp-hz = /bits/ 64 <5000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-8000000 {
> +			opp-hz = /bits/ 64 <8000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +	};
> +
> +	pcie1_opp_table: opp-table-pcie1 {
> +		compatible = "operating-points-v2";
> +
> +		opp-2500000 {
> +			opp-hz = /bits/ 64 <2500000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-5000000 {
> +			opp-hz = /bits/ 64 <5000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-8000000 {
> +			opp-hz = /bits/ 64 <8000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-16000000 {
> +			opp-hz = /bits/ 64 <16000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
> +		};
> +	};
> +
>  	reserved_memory: reserved-memory {
>  		#address-cells = <2>;
>  		#size-cells = <2>;
> @@ -1803,6 +1846,8 @@
>  			pinctrl-names = "default";
>  			pinctrl-0 = <&pcie0_default_state>;
>  
> +			operating-points-v2 = <&pcie0_opp_table>;

Why the table is not here? Is it shared with multiple devices?

Best regards,
Krzysztof

Re: [PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH

[kernel test robot]

Hi Krishna,

kernel test robot noticed the following build warnings:

[auto build test WARNING on pci/for-linus]
[also build test WARNING on robh/for-next linus/master v6.5-rc6 next-20230809]
[cannot apply to pci/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Krishna-chaitanya-chundru/dt-bindings-pci-qcom-Add-binding-for-operating-points-v2/20230815-203103
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git for-linus
patch link:    https://lore.kernel.org/r/1692102408-7010-4-git-send-email-quic_krichai%40quicinc.com
patch subject: [PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH
config: loongarch-allyesconfig (https://download.01.org/0day-ci/archive/20230815/202308152125.sU1aQfAd-lkp@intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230815/202308152125.sU1aQfAd-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308152125.sU1aQfAd-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/pci/controller/dwc/pcie-qcom.c: In function 'qcom_pcie_opp_update':
>> drivers/pci/controller/dwc/pcie-qcom.c:1368:13: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
    1368 |         int ret = 0;
         |             ^~~


vim +/ret +1368 drivers/pci/controller/dwc/pcie-qcom.c

  1360	
  1361	static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
  1362	{
  1363		struct dw_pcie *pci = pcie->pci;
  1364		struct dev_pm_opp *opp;
  1365		u32 offset, status;
  1366		uint32_t freq;
  1367		int speed;
> 1368		int ret = 0;
  1369	
  1370		offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
  1371		status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
  1372	
  1373		/* Only update constraints if link is up. */
  1374		if (!(status & PCI_EXP_LNKSTA_DLLLA))
  1375			return;
  1376	
  1377		speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
  1378	
  1379		switch (speed) {
  1380		case 1:
  1381			freq = 2500000;
  1382			break;
  1383		case 2:
  1384			freq = 5000000;
  1385			break;
  1386		case 3:
  1387			freq = 8000000;
  1388			break;
  1389		default:
  1390			WARN_ON_ONCE(1);
  1391			fallthrough;
  1392		case 4:
  1393			freq = 16000000;
  1394			break;
  1395		}
  1396	
  1397		opp = dev_pm_opp_find_freq_exact(pci->dev, freq, true);
  1398	
  1399		if (!IS_ERR(opp)) {
  1400			ret = dev_pm_opp_get_voltage(opp);
  1401			dev_pm_opp_put(opp);
  1402		}
  1403	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH

[Pavan Kondeti]

On Tue, Aug 15, 2023 at 05:56:48PM +0530, Krishna chaitanya chundru wrote:
> Before link training vote for the maximum performance state of RPMH
> and once the link is up, vote for the performance state based upon
> the link speed.
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 61 ++++++++++++++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 7a87a47..e29a986 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -22,6 +22,7 @@
>  #include <linux/of_device.h>
>  #include <linux/of_gpio.h>
>  #include <linux/pci.h>
> +#include <linux/pm_opp.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/platform_device.h>
>  #include <linux/phy/pcie.h>
> @@ -1357,6 +1358,51 @@ static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
>  	return 0;
>  }
>  
> +static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
> +{
> +	struct dw_pcie *pci = pcie->pci;
> +	struct dev_pm_opp *opp;
> +	u32 offset, status;
> +	uint32_t freq;
> +	int speed;
> +	int ret = 0;
> +
> +	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
> +	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
> +
> +	/* Only update constraints if link is up. */
> +	if (!(status & PCI_EXP_LNKSTA_DLLLA))
> +		return;
> +
> +	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
> +
> +	switch (speed) {
> +	case 1:
> +		freq = 2500000;
> +		break;
> +	case 2:
> +		freq = 5000000;
> +		break;
> +	case 3:
> +		freq = 8000000;
> +		break;
> +	default:
> +		WARN_ON_ONCE(1);
> +		fallthrough;
> +	case 4:
> +		freq = 16000000;
> +		break;
> +	}
> +
> +	opp = dev_pm_opp_find_freq_exact(pci->dev, freq, true);
> +
> +	if (!IS_ERR(opp)) {
> +		ret = dev_pm_opp_get_voltage(opp);
> +		dev_pm_opp_put(opp);
> +	}
> +

Where are we setting the OPP here?

> +}
> +
>  static void qcom_pcie_icc_update(struct qcom_pcie *pcie)
>  {
>  	struct dw_pcie *pci = pcie->pci;
> @@ -1439,8 +1485,10 @@ static void qcom_pcie_init_debugfs(struct qcom_pcie *pcie)
>  static int qcom_pcie_probe(struct platform_device *pdev)
>  {
>  	const struct qcom_pcie_cfg *pcie_cfg;
> +	unsigned long max_freq = INT_MAX;
>  	struct device *dev = &pdev->dev;
>  	struct qcom_pcie *pcie;
> +	struct dev_pm_opp *opp;
>  	struct dw_pcie_rp *pp;
>  	struct resource *res;
>  	struct dw_pcie *pci;
> @@ -1511,6 +1559,17 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto err_pm_runtime_put;
>  
> +	/* OPP table is optional */
> +	ret = devm_pm_opp_of_add_table(dev);
> +	if (ret && ret != -ENODEV) {
> +		dev_err(dev, "Invalid OPP table in Device tree\n");
> +		goto err_pm_runtime_put;
> +	}
> +
> +	opp = dev_pm_opp_find_freq_floor(dev, &max_freq);
> +	if (!IS_ERR(opp))
> +		dev_pm_opp_put(opp);
> +

This OPP (corresponding to max freq) is not used, so how are we voting
for max perf state during probe?

>  	ret = pcie->cfg->ops->get_resources(pcie);
>  	if (ret)
>  		goto err_pm_runtime_put;
> @@ -1531,6 +1590,8 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>  
>  	qcom_pcie_icc_update(pcie);
>  
> +	qcom_pcie_opp_update(pcie);
> +

commit description says, OPP voting is done as per the link speed after
probe? I don't see any calls to qcom_pcie_opp_update() outside probe.

>  	if (pcie->mhi)
>  		qcom_pcie_init_debugfs(pcie);
>  
> 

Thanks,
Pavan

Re: [PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Pavan Kondeti]

On Tue, Aug 15, 2023 at 05:56:47PM +0530, Krishna chaitanya chundru wrote:
> PCIe needs to choose the appropriate performance state of RPMH power
> domain based upon the PCIe gen speed.
> 
> So, let's add the OPP table support to specify RPMH performance states.
> 
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> index 595533a..681ea9c 100644
> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
> @@ -381,6 +381,49 @@
>  		};
>  	};
>  
> +	pcie0_opp_table: opp-table-pcie0 {
> +		compatible = "operating-points-v2";
> +
> +		opp-2500000 {
> +			opp-hz = /bits/ 64 <2500000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-5000000 {
> +			opp-hz = /bits/ 64 <5000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-8000000 {
> +			opp-hz = /bits/ 64 <8000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +	};
> +
> +	pcie1_opp_table: opp-table-pcie1 {
> +		compatible = "operating-points-v2";
> +
> +		opp-2500000 {
> +			opp-hz = /bits/ 64 <2500000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-5000000 {
> +			opp-hz = /bits/ 64 <5000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-8000000 {
> +			opp-hz = /bits/ 64 <8000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
> +		};
> +
> +		opp-16000000 {
> +			opp-hz = /bits/ 64 <16000000>;
> +			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
> +		};
> +	};
> +

Should not we using required-opps property to pass the
rpmhpd_opp_xxx phandle so that when this OPP is selected based on your
clock rate, the appropriate OPP (voltage) would be selected on the RPMH side?

Please see SDHCI/MMC voting (sdhc2_opp_table) as an example.

Thanks,
Pavan

Re: [PATCH v1 1/3] dt-bindings: pci: qcom: Add binding for operating-points-v2

[Krishna Chaitanya Chundru]

On 8/15/2023 6:00 PM, Krzysztof Kozlowski wrote:
> On 15/08/2023 14:26, Krishna chaitanya chundru wrote:
>> This adds a binding documenting operating-points-v2.
> 1. Missing blank line. Don't write patches by yourself, but use tools
> which create proper commit automatically. Every decent editor does it.
>
> 2. Please do not use "This commit/patch", but imperative mood. See
> longer explanation here:
> https://elixir.bootlin.com/linux/v5.17.1/source/Documentation/process/submitting-patches.rst#L95
>
> 3. A nit, subject: drop second/last, redundant "binding for". The
> "dt-bindings" prefix is already stating that these are bindings.
>
>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   Documentation/devicetree/bindings/pci/qcom,pcie.yaml | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>> index 81971be4..6bc99c5 100644
>> --- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>> +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml
>> @@ -121,6 +121,8 @@ properties:
>>       description: GPIO controlled connection to WAKE# signal
>>       maxItems: 1
>>   
>> +  operating-points-v2: true
> phandle without actual table (opp-table) is rather meaningless.
>
> Best regards,
> Krzysztof

I will take all your comments and will send next patch

- KC

Re: [PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Krishna Chaitanya Chundru]

On 8/15/2023 6:01 PM, Krzysztof Kozlowski wrote:
> On 15/08/2023 14:26, Krishna chaitanya chundru wrote:
>> PCIe needs to choose the appropriate performance state of RPMH power
>> domain based upon the PCIe gen speed.
> This explanation should be also in bindings patch, otherwise why would
> we consider the bindings patch?
I will update binding patch with this information.
>
>> So, let's add the OPP table support to specify RPMH performance states.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
>>   1 file changed, 47 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> index 595533a..681ea9c 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> @@ -381,6 +381,49 @@
>>   		};
>>   	};
>>   
>> +	pcie0_opp_table: opp-table-pcie0 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +	};
>> +
>> +	pcie1_opp_table: opp-table-pcie1 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-16000000 {
>> +			opp-hz = /bits/ 64 <16000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
>> +		};
>> +	};
>> +
>>   	reserved_memory: reserved-memory {
>>   		#address-cells = <2>;
>>   		#size-cells = <2>;
>> @@ -1803,6 +1846,8 @@
>>   			pinctrl-names = "default";
>>   			pinctrl-0 = <&pcie0_default_state>;
>>   
>> +			operating-points-v2 = <&pcie0_opp_table>;
> Why the table is not here? Is it shared with multiple devices?

I will move the table to here in the next patch.

- KC

>
> Best regards,
> Krzysztof
>

Re: [PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Krishna Chaitanya Chundru]

On 8/16/2023 12:35 PM, Pavan Kondeti wrote:
> On Tue, Aug 15, 2023 at 05:56:47PM +0530, Krishna chaitanya chundru wrote:
>> PCIe needs to choose the appropriate performance state of RPMH power
>> domain based upon the PCIe gen speed.
>>
>> So, let's add the OPP table support to specify RPMH performance states.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
>>   1 file changed, 47 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> index 595533a..681ea9c 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> @@ -381,6 +381,49 @@
>>   		};
>>   	};
>>   
>> +	pcie0_opp_table: opp-table-pcie0 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +	};
>> +
>> +	pcie1_opp_table: opp-table-pcie1 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-16000000 {
>> +			opp-hz = /bits/ 64 <16000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
>> +		};
>> +	};
>> +
> Should not we using required-opps property to pass the
> rpmhpd_opp_xxx phandle so that when this OPP is selected based on your
> clock rate, the appropriate OPP (voltage) would be selected on the RPMH side?
>
> Please see SDHCI/MMC voting (sdhc2_opp_table) as an example.

Sure I will try to use rpmhpd_opp_xxx phandle in next patch

- KC

>
> Thanks,
> Pavan

Re: [PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH

[Krishna Chaitanya Chundru]

On 8/16/2023 11:54 AM, Pavan Kondeti wrote:
> On Tue, Aug 15, 2023 at 05:56:48PM +0530, Krishna chaitanya chundru wrote:
>> Before link training vote for the maximum performance state of RPMH
>> and once the link is up, vote for the performance state based upon
>> the link speed.
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   drivers/pci/controller/dwc/pcie-qcom.c | 61 ++++++++++++++++++++++++++++++++++
>>   1 file changed, 61 insertions(+)
>>
>> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
>> index 7a87a47..e29a986 100644
>> --- a/drivers/pci/controller/dwc/pcie-qcom.c
>> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
>> @@ -22,6 +22,7 @@
>>   #include <linux/of_device.h>
>>   #include <linux/of_gpio.h>
>>   #include <linux/pci.h>
>> +#include <linux/pm_opp.h>
>>   #include <linux/pm_runtime.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/phy/pcie.h>
>> @@ -1357,6 +1358,51 @@ static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
>>   	return 0;
>>   }
>>   
>> +static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
>> +{
>> +	struct dw_pcie *pci = pcie->pci;
>> +	struct dev_pm_opp *opp;
>> +	u32 offset, status;
>> +	uint32_t freq;
>> +	int speed;
>> +	int ret = 0;
>> +
>> +	offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
>> +	status = readw(pci->dbi_base + offset + PCI_EXP_LNKSTA);
>> +
>> +	/* Only update constraints if link is up. */
>> +	if (!(status & PCI_EXP_LNKSTA_DLLLA))
>> +		return;
>> +
>> +	speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
>> +
>> +	switch (speed) {
>> +	case 1:
>> +		freq = 2500000;
>> +		break;
>> +	case 2:
>> +		freq = 5000000;
>> +		break;
>> +	case 3:
>> +		freq = 8000000;
>> +		break;
>> +	default:
>> +		WARN_ON_ONCE(1);
>> +		fallthrough;
>> +	case 4:
>> +		freq = 16000000;
>> +		break;
>> +	}
>> +
>> +	opp = dev_pm_opp_find_freq_exact(pci->dev, freq, true);
>> +
>> +	if (!IS_ERR(opp)) {
>> +		ret = dev_pm_opp_get_voltage(opp);
>> +		dev_pm_opp_put(opp);
>> +	}
>> +
> Where are we setting the OPP here?
>
>> +}
>> +
>>   static void qcom_pcie_icc_update(struct qcom_pcie *pcie)
>>   {
>>   	struct dw_pcie *pci = pcie->pci;
>> @@ -1439,8 +1485,10 @@ static void qcom_pcie_init_debugfs(struct qcom_pcie *pcie)
>>   static int qcom_pcie_probe(struct platform_device *pdev)
>>   {
>>   	const struct qcom_pcie_cfg *pcie_cfg;
>> +	unsigned long max_freq = INT_MAX;
>>   	struct device *dev = &pdev->dev;
>>   	struct qcom_pcie *pcie;
>> +	struct dev_pm_opp *opp;
>>   	struct dw_pcie_rp *pp;
>>   	struct resource *res;
>>   	struct dw_pcie *pci;
>> @@ -1511,6 +1559,17 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>>   	if (ret)
>>   		goto err_pm_runtime_put;
>>   
>> +	/* OPP table is optional */
>> +	ret = devm_pm_opp_of_add_table(dev);
>> +	if (ret && ret != -ENODEV) {
>> +		dev_err(dev, "Invalid OPP table in Device tree\n");
>> +		goto err_pm_runtime_put;
>> +	}
>> +
>> +	opp = dev_pm_opp_find_freq_floor(dev, &max_freq);
>> +	if (!IS_ERR(opp))
>> +		dev_pm_opp_put(opp);
>> +
> This OPP (corresponding to max freq) is not used, so how are we voting
> for max perf state during probe?
>
>>   	ret = pcie->cfg->ops->get_resources(pcie);
>>   	if (ret)
>>   		goto err_pm_runtime_put;
>> @@ -1531,6 +1590,8 @@ static int qcom_pcie_probe(struct platform_device *pdev)
>>   
>>   	qcom_pcie_icc_update(pcie);
>>   
>> +	qcom_pcie_opp_update(pcie);
>> +
> commit description says, OPP voting is done as per the link speed after
> probe? I don't see any calls to qcom_pcie_opp_update() outside probe.

my mistake dev_pm_opp_set_opp somehow missed here I will update in next 
patch.

- KC

>>   	if (pcie->mhi)
>>   		qcom_pcie_init_debugfs(pcie);
>>   
>>
> Thanks,
> Pavan

Re: [PATCH v1 2/3] arm64: dts: qcom: sm8450: Add opp table support to PCIe

[Konrad Dybcio]

On 16.08.2023 09:05, Pavan Kondeti wrote:
> On Tue, Aug 15, 2023 at 05:56:47PM +0530, Krishna chaitanya chundru wrote:
>> PCIe needs to choose the appropriate performance state of RPMH power
>> domain based upon the PCIe gen speed.
>>
>> So, let's add the OPP table support to specify RPMH performance states.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 47 ++++++++++++++++++++++++++++++++++++
>>  1 file changed, 47 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> index 595533a..681ea9c 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> @@ -381,6 +381,49 @@
>>  		};
>>  	};
>>  
>> +	pcie0_opp_table: opp-table-pcie0 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +	};
>> +
>> +	pcie1_opp_table: opp-table-pcie1 {
>> +		compatible = "operating-points-v2";
>> +
>> +		opp-2500000 {
>> +			opp-hz = /bits/ 64 <2500000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-5000000 {
>> +			opp-hz = /bits/ 64 <5000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-8000000 {
>> +			opp-hz = /bits/ 64 <8000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_LOW_SVS>;
>> +		};
>> +
>> +		opp-16000000 {
>> +			opp-hz = /bits/ 64 <16000000>;
>> +			opp-level = <RPMH_REGULATOR_LEVEL_NOM>;
>> +		};
>> +	};
>> +
> 
> Should not we using required-opps property to pass the
> rpmhpd_opp_xxx phandle so that when this OPP is selected based on your
> clock rate, the appropriate OPP (voltage) would be selected on the RPMH side?
Yes, opp-level is for opp providers.

Konrad

Re: [PATCH v1 3/3] PCI: qcom: Add OPP suuport for speed based performance state of RPMH

[Konrad Dybcio]

On 15.08.2023 14:26, Krishna chaitanya chundru wrote:
> Before link training vote for the maximum performance state of RPMH
> and once the link is up, vote for the performance state based upon
> the link speed.
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 61 ++++++++++++++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 7a87a47..e29a986 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -22,6 +22,7 @@
>  #include <linux/of_device.h>
>  #include <linux/of_gpio.h>
>  #include <linux/pci.h>
> +#include <linux/pm_opp.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/platform_device.h>
>  #include <linux/phy/pcie.h>
> @@ -1357,6 +1358,51 @@ static int qcom_pcie_icc_init(struct qcom_pcie *pcie)
>  	return 0;
>  }
>  
> +static void qcom_pcie_opp_update(struct qcom_pcie *pcie)
> +{
> +	struct dw_pcie *pci = pcie->pci;
> +	struct dev_pm_opp *opp;
> +	u32 offset, status;
> +	uint32_t freq;
> +	int speed;
> +	int ret = 0;
On top of Krzysztof's comments:

ret is effectively unused

[...]

> +	opp = dev_pm_opp_find_freq_exact(pci->dev, freq, true);
> +
> +	if (!IS_ERR(opp)) {
Unnecessary newline

Konrad