summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/devicetree/bindings/pci/qcom,pcie.yaml22
-rw-r--r--drivers/pci/controller/dwc/pcie-qcom.c76
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: