PCI: plda: Add host init/deinit and map bus functions

Add PLDA host plda_pcie_host_init()/plda_pcie_host_deinit() and map bus
function so vendors can use it to init PLDA PCIe host core.

Link: https://lore.kernel.org/linux-pci/20240328091835.14797-19-minda.chen@starfivetech.com
Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mason Huo <mason.huo@starfivetech.com>

Author: mindachen1987

drivers/pci/controller/plda/pcie-plda-host.c

@@ -3,6 +3,7 @@
  * PLDA PCIe XpressRich host controller driver
  *
  * Copyright (C) 2023 Microchip Co. Ltd
+ *		      StarFive Co. Ltd
  *
  * Author: Daire McNamara <daire.mcnamara@microchip.com>
  */
@@ -15,6 +16,15 @@
 
 #include "pcie-plda.h"
 
+void __iomem *plda_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
+				int where)
+{
+	struct plda_pcie_rp *pcie = bus->sysdata;
+
+	return pcie->config_base + PCIE_ECAM_OFFSET(bus->number, devfn, where);
+}
+EXPORT_SYMBOL_GPL(plda_pcie_map_bus);
+
 static void plda_handle_msi(struct irq_desc *desc)
 {
 	struct plda_pcie_rp *port = irq_desc_get_handler_data(desc);
@@ -420,9 +430,7 @@ int plda_init_interrupts(struct platform_device *pdev,
 			 const struct plda_event *event)
 {
 	struct device *dev = &pdev->dev;
-	int irq;
-	int intx_irq, msi_irq, event_irq;
-	int ret;
+	int event_irq, ret;
 	u32 i;
 
 	if (!port->event_ops)
@@ -437,8 +445,8 @@ int plda_init_interrupts(struct platform_device *pdev,
 		return ret;
 	}
 
-	irq = platform_get_irq(pdev, 0);
-	if (irq < 0)
+	port->irq = platform_get_irq(pdev, 0);
+	if (port->irq < 0)
 		return -ENODEV;
 
 	for_each_set_bit(i, &port->events_bitmap, port->num_events) {
@@ -461,26 +469,26 @@ int plda_init_interrupts(struct platform_device *pdev,
 		}
 	}
 
-	intx_irq = irq_create_mapping(port->event_domain,
-				      event->intx_event);
-	if (!intx_irq) {
+	port->intx_irq = irq_create_mapping(port->event_domain,
+					    event->intx_event);
+	if (!port->intx_irq) {
 		dev_err(dev, "failed to map INTx interrupt\n");
 		return -ENXIO;
 	}
 
 	/* Plug the INTx chained handler */
-	irq_set_chained_handler_and_data(intx_irq, plda_handle_intx, port);
+	irq_set_chained_handler_and_data(port->intx_irq, plda_handle_intx, port);
 
-	msi_irq = irq_create_mapping(port->event_domain,
-				     event->msi_event);
-	if (!msi_irq)
+	port->msi_irq = irq_create_mapping(port->event_domain,
+					   event->msi_event);
+	if (!port->msi_irq)
 		return -ENXIO;
 
 	/* Plug the MSI chained handler */
-	irq_set_chained_handler_and_data(msi_irq, plda_handle_msi, port);
+	irq_set_chained_handler_and_data(port->msi_irq, plda_handle_msi, port);
 
 	/* Plug the main event chained handler */
-	irq_set_chained_handler_and_data(irq, plda_handle_event, port);
+	irq_set_chained_handler_and_data(port->irq, plda_handle_event, port);
 
 	return 0;
 }
@@ -547,3 +555,98 @@ int plda_pcie_setup_iomems(struct platform_device *pdev,
 	return 0;
 }
 EXPORT_SYMBOL_GPL(plda_pcie_setup_iomems);
+
+static void plda_pcie_irq_domain_deinit(struct plda_pcie_rp *pcie)
+{
+	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
+	irq_set_chained_handler_and_data(pcie->msi_irq, NULL, NULL);
+	irq_set_chained_handler_and_data(pcie->intx_irq, NULL, NULL);
+
+	irq_domain_remove(pcie->msi.msi_domain);
+	irq_domain_remove(pcie->msi.dev_domain);
+
+	irq_domain_remove(pcie->intx_domain);
+	irq_domain_remove(pcie->event_domain);
+}
+
+int plda_pcie_host_init(struct plda_pcie_rp *port, struct pci_ops *ops,
+			const struct plda_event *plda_event)
+{
+	struct device *dev = port->dev;
+	struct pci_host_bridge *bridge;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct resource *cfg_res;
+	int ret;
+
+	pdev = to_platform_device(dev);
+
+	port->bridge_addr =
+		devm_platform_ioremap_resource_byname(pdev, "apb");
+
+	if (IS_ERR(port->bridge_addr))
+		return dev_err_probe(dev, PTR_ERR(port->bridge_addr),
+				     "failed to map reg memory\n");
+
+	cfg_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+	if (!cfg_res)
+		return dev_err_probe(dev, -ENODEV,
+				     "failed to get config memory\n");
+
+	port->config_base = devm_ioremap_resource(dev, cfg_res);
+	if (IS_ERR(port->config_base))
+		return dev_err_probe(dev, PTR_ERR(port->config_base),
+				     "failed to map config memory\n");
+
+	bridge = devm_pci_alloc_host_bridge(dev, 0);
+	if (!bridge)
+		return dev_err_probe(dev, -ENOMEM,
+				     "failed to alloc bridge\n");
+
+	if (port->host_ops && port->host_ops->host_init) {
+		ret = port->host_ops->host_init(port);
+		if (ret)
+			return ret;
+	}
+
+	port->bridge = bridge;
+	plda_pcie_setup_window(port->bridge_addr, 0, cfg_res->start, 0,
+			       resource_size(cfg_res));
+	plda_pcie_setup_iomems(bridge, port);
+	plda_set_default_msi(&port->msi);
+	ret = plda_init_interrupts(pdev, port, plda_event);
+	if (ret)
+		goto err_host;
+
+	/* Set default bus ops */
+	bridge->ops = ops;
+	bridge->sysdata = port;
+
+	ret = pci_host_probe(bridge);
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to probe pci host\n");
+		goto err_probe;
+	}
+
+	return ret;
+
+err_probe:
+	plda_pcie_irq_domain_deinit(port);
+err_host:
+	if (port->host_ops && port->host_ops->host_deinit)
+		port->host_ops->host_deinit(port);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(plda_pcie_host_init);
+
+void plda_pcie_host_deinit(struct plda_pcie_rp *port)
+{
+	pci_stop_root_bus(port->bridge->bus);
+	pci_remove_root_bus(port->bridge->bus);
+
+	plda_pcie_irq_domain_deinit(port);
+
+	if (port->host_ops && port->host_ops->host_deinit)
+		port->host_ops->host_deinit(port);
+}
+EXPORT_SYMBOL_GPL(plda_pcie_host_deinit);

drivers/pci/controller/plda/pcie-plda.h

@@ -142,6 +142,11 @@ struct plda_event_ops {
 	u32 (*get_events)(struct plda_pcie_rp *pcie);
 };
 
+struct plda_pcie_host_ops {
+	int (*host_init)(struct plda_pcie_rp *pcie);
+	void (*host_deinit)(struct plda_pcie_rp *pcie);
+};
+
 struct plda_msi {
 	struct mutex lock;		/* Protect used bitmap */
 	struct irq_domain *msi_domain;
@@ -153,14 +158,20 @@ struct plda_msi {
 
 struct plda_pcie_rp {
 	struct device *dev;
+	struct pci_host_bridge *bridge;
 	struct irq_domain *intx_domain;
 	struct irq_domain *event_domain;
 	raw_spinlock_t lock;
 	struct plda_msi msi;
 	const struct plda_event_ops *event_ops;
 	const struct irq_chip *event_irq_chip;
+	const struct plda_pcie_host_ops *host_ops;
 	void __iomem *bridge_addr;
+	void __iomem *config_base;
 	unsigned long events_bitmap;
+	int irq;
+	int msi_irq;
+	int intx_irq;
 	int num_events;
 };
 
@@ -171,6 +182,8 @@ struct plda_event {
 	int msi_event;
 };
 
+void __iomem *plda_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
+				int where);
 int plda_init_interrupts(struct platform_device *pdev,
 			 struct plda_pcie_rp *port,
 			 const struct plda_event *event);
@@ -179,4 +192,13 @@ void plda_pcie_setup_window(void __iomem *bridge_base_addr, u32 index,
 			    size_t size);
 int plda_pcie_setup_iomems(struct platform_device *pdev,
 			   struct plda_pcie_rp *port);
+int plda_pcie_host_init(struct plda_pcie_rp *port, struct pci_ops *ops,
+			const struct plda_event *plda_event);
+void plda_pcie_host_deinit(struct plda_pcie_rp *pcie);
+
+static inline void plda_set_default_msi(struct plda_msi *msi)
+{
+	msi->vector_phy = IMSI_ADDR;
+	msi->num_vectors = PLDA_MAX_NUM_MSI_IRQS;
+}
 #endif