diff options
-rw-r--r-- | Documentation/devicetree/bindings/pci/qcom,pcie.yaml | 22 | ||||
-rw-r--r-- | drivers/pci/controller/dwc/pcie-qcom.c | 76 |
2 files changed, 98 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml index 54f07852d279..a5859bb3dc28 100644 --- a/Documentation/devicetree/bindings/pci/qcom,pcie.yaml +++ b/Documentation/devicetree/bindings/pci/qcom,pcie.yaml @@ -62,6 +62,16 @@ properties: minItems: 3 maxItems: 13 + dma-coherent: true + + interconnects: + maxItems: 2 + + interconnect-names: + items: + - const: pcie-mem + - const: cpu-pcie + resets: minItems: 1 maxItems: 12 @@ -632,6 +642,18 @@ allOf: - const: pci # PCIe core reset - if: + properties: + compatible: + contains: + enum: + - qcom,pcie-sa8540p + - qcom,pcie-sc8280xp + then: + required: + - interconnects + - interconnect-names + + - if: not: properties: compatible: diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c index cf27345f6575..38d5d46487bb 100644 --- a/drivers/pci/controller/dwc/pcie-qcom.c +++ b/drivers/pci/controller/dwc/pcie-qcom.c @@ -12,6 +12,7 @@ #include <linux/crc8.h> #include <linux/delay.h> #include <linux/gpio/consumer.h> +#include <linux/interconnect.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> @@ -223,6 +224,7 @@ struct qcom_pcie { union qcom_pcie_resources res; struct phy *phy; struct gpio_desc *reset; + struct icc_path *icc_mem; const struct qcom_pcie_cfg *cfg; }; @@ -1639,6 +1641,74 @@ static const struct dw_pcie_ops dw_pcie_ops = { .start_link = qcom_pcie_start_link, }; +static int qcom_pcie_icc_init(struct qcom_pcie *pcie) +{ + struct dw_pcie *pci = pcie->pci; + int ret; + + pcie->icc_mem = devm_of_icc_get(pci->dev, "pcie-mem"); + if (IS_ERR(pcie->icc_mem)) + return PTR_ERR(pcie->icc_mem); + + /* + * Some Qualcomm platforms require interconnect bandwidth constraints + * to be set before enabling interconnect clocks. + * + * Set an initial peak bandwidth corresponding to single-lane Gen 1 + * for the pcie-mem path. + */ + ret = icc_set_bw(pcie->icc_mem, 0, MBps_to_icc(250)); + if (ret) { + dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n", + ret); + return ret; + } + + return 0; +} + +static void qcom_pcie_icc_update(struct qcom_pcie *pcie) +{ + struct dw_pcie *pci = pcie->pci; + u32 offset, status, bw; + int speed, width; + int ret; + + if (!pcie->icc_mem) + return; + + 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); + width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status); + + switch (speed) { + case 1: + bw = MBps_to_icc(250); + break; + case 2: + bw = MBps_to_icc(500); + break; + default: + WARN_ON_ONCE(1); + fallthrough; + case 3: + bw = MBps_to_icc(985); + break; + } + + ret = icc_set_bw(pcie->icc_mem, 0, width * bw); + if (ret) { + dev_err(pci->dev, "failed to set interconnect bandwidth: %d\n", + ret); + } +} + static int qcom_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -1699,6 +1769,10 @@ static int qcom_pcie_probe(struct platform_device *pdev) goto err_pm_runtime_put; } + ret = qcom_pcie_icc_init(pcie); + if (ret) + goto err_pm_runtime_put; + ret = pcie->cfg->ops->get_resources(pcie); if (ret) goto err_pm_runtime_put; @@ -1717,6 +1791,8 @@ static int qcom_pcie_probe(struct platform_device *pdev) goto err_phy_exit; } + qcom_pcie_icc_update(pcie); + return 0; err_phy_exit: |