PCI: cadence: Add generic PHY support to host and EP drivers

If PHYs are present, initialize and enable them at driver probe.

Signed-off-by: Alan Douglas <adouglas@cadence.com>
[lorenzo.pieralisi@arm.com: updated commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>

drivers/pci/controller/pcie-cadence.c

@@ -124,3 +124,96 @@ void cdns_pcie_reset_outbound_region(struct cdns_pcie *pcie, u32 r)
 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), 0);
 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), 0);
 }
+
+void cdns_pcie_disable_phy(struct cdns_pcie *pcie)
+{
+	int i = pcie->phy_count;
+
+	while (i--) {
+		phy_power_off(pcie->phy[i]);
+		phy_exit(pcie->phy[i]);
+	}
+}
+
+int cdns_pcie_enable_phy(struct cdns_pcie *pcie)
+{
+	int ret;
+	int i;
+
+	for (i = 0; i < pcie->phy_count; i++) {
+		ret = phy_init(pcie->phy[i]);
+		if (ret < 0)
+			goto err_phy;
+
+		ret = phy_power_on(pcie->phy[i]);
+		if (ret < 0) {
+			phy_exit(pcie->phy[i]);
+			goto err_phy;
+		}
+	}
+
+	return 0;
+
+err_phy:
+	while (--i >= 0) {
+		phy_power_off(pcie->phy[i]);
+		phy_exit(pcie->phy[i]);
+	}
+
+	return ret;
+}
+
+int cdns_pcie_init_phy(struct device *dev, struct cdns_pcie *pcie)
+{
+	struct device_node *np = dev->of_node;
+	int phy_count;
+	struct phy **phy;
+	struct device_link **link;
+	int i;
+	int ret;
+	const char *name;
+
+	phy_count = of_property_count_strings(np, "phy-names");
+	if (phy_count < 1) {
+		dev_err(dev, "no phy-names.  PHY will not be initialized\n");
+		pcie->phy_count = 0;
+		return 0;
+	}
+
+	phy = devm_kzalloc(dev, sizeof(*phy) * phy_count, GFP_KERNEL);
+	if (!phy)
+		return -ENOMEM;
+
+	link = devm_kzalloc(dev, sizeof(*link) * phy_count, GFP_KERNEL);
+	if (!link)
+		return -ENOMEM;
+
+	for (i = 0; i < phy_count; i++) {
+		of_property_read_string_index(np, "phy-names", i, &name);
+		phy[i] = devm_phy_optional_get(dev, name);
+		if (IS_ERR(phy))
+			return PTR_ERR(phy);
+
+		link[i] = device_link_add(dev, &phy[i]->dev, DL_FLAG_STATELESS);
+		if (!link[i]) {
+			ret = -EINVAL;
+			goto err_link;
+		}
+	}
+
+	pcie->phy_count = phy_count;
+	pcie->phy = phy;
+	pcie->link = link;
+
+	ret =  cdns_pcie_enable_phy(pcie);
+	if (ret)
+		goto err_link;
+
+	return 0;
+
+err_link:
+	while (--i >= 0)
+		device_link_del(link[i]);
+
+	return ret;
+}