PCI: cadence: Refactor driver to use as a core library

Cadence PCIe host and endpoint IP may be embedded into a variety of
SoCs/platforms. Let's extract the platform related APIs/Structures in the
current driver to a separate file (pcie-cadence-plat.c), such that the
common functionality can be used by future platforms.

Signed-off-by: Tom Joseph <tjoseph@cadence.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>

drivers/pci/controller/Kconfig

@@ -28,23 +28,38 @@ config PCIE_CADENCE
 	bool
 
 config PCIE_CADENCE_HOST
-	bool "Cadence PCIe host controller"
+	bool
 	depends on OF
-	depends on PCI
 	select IRQ_DOMAIN
 	select PCIE_CADENCE
-	help
-	  Say Y here if you want to support the Cadence PCIe controller in host
-	  mode. This PCIe controller may be embedded into many different vendors
-	  SoCs.
 
 config PCIE_CADENCE_EP
-	bool "Cadence PCIe endpoint controller"
+	bool
 	depends on OF
 	depends on PCI_ENDPOINT
 	select PCIE_CADENCE
+
+config PCIE_CADENCE_PLAT
+	bool
+
+config PCIE_CADENCE_PLAT_HOST
+	bool "Cadence PCIe platform host controller"
+	depends on OF
+	select PCIE_CADENCE_HOST
+	select PCIE_CADENCE_PLAT
 	help
-	  Say Y here if you want to support the Cadence PCIe  controller in
+	  Say Y here if you want to support the Cadence PCIe platform controller in
+	  host mode. This PCIe controller may be embedded into many different
+	  vendors SoCs.
+
+config PCIE_CADENCE_PLAT_EP
+	bool "Cadence PCIe platform endpoint controller"
+	depends on OF
+	depends on PCI_ENDPOINT
+	select PCIE_CADENCE_EP
+	select PCIE_CADENCE_PLAT
+	help
+	  Say Y here if you want to support the Cadence PCIe  platform controller in
 	  endpoint mode. This PCIe controller may be embedded into many
 	  different vendors SoCs.
 

drivers/pci/controller/Makefile

@@ -2,6 +2,7 @@
 obj-$(CONFIG_PCIE_CADENCE) += pcie-cadence.o
 obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host.o
 obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o
+obj-$(CONFIG_PCIE_CADENCE_PLAT) += pcie-cadence-plat.o
 obj-$(CONFIG_PCI_FTPCI100) += pci-ftpci100.o
 obj-$(CONFIG_PCI_HYPERV) += pci-hyperv.o
 obj-$(CONFIG_PCI_HYPERV_INTERFACE) += pci-hyperv-intf.o

drivers/pci/controller/pcie-cadence-ep.c

@@ -17,35 +17,6 @@
 #define CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE		0x1
 #define CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY	0x3
 
-/**
- * struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
- * @pcie: Cadence PCIe controller
- * @max_regions: maximum number of regions supported by hardware
- * @ob_region_map: bitmask of mapped outbound regions
- * @ob_addr: base addresses in the AXI bus where the outbound regions start
- * @irq_phys_addr: base address on the AXI bus where the MSI/legacy IRQ
- *		   dedicated outbound regions is mapped.
- * @irq_cpu_addr: base address in the CPU space where a write access triggers
- *		  the sending of a memory write (MSI) / normal message (legacy
- *		  IRQ) TLP through the PCIe bus.
- * @irq_pci_addr: used to save the current mapping of the MSI/legacy IRQ
- *		  dedicated outbound region.
- * @irq_pci_fn: the latest PCI function that has updated the mapping of
- *		the MSI/legacy IRQ dedicated outbound region.
- * @irq_pending: bitmask of asserted legacy IRQs.
- */
-struct cdns_pcie_ep {
-	struct cdns_pcie		pcie;
-	u32				max_regions;
-	unsigned long			ob_region_map;
-	phys_addr_t			*ob_addr;
-	phys_addr_t			irq_phys_addr;
-	void __iomem			*irq_cpu_addr;
-	u64				irq_pci_addr;
-	u8				irq_pci_fn;
-	u8				irq_pending;
-};
-
 static int cdns_pcie_ep_write_header(struct pci_epc *epc, u8 fn,
 				     struct pci_epf_header *hdr)
 {
@@ -424,28 +395,17 @@ static const struct pci_epc_ops cdns_pcie_epc_ops = {
 	.get_features	= cdns_pcie_ep_get_features,
 };
 
-static const struct of_device_id cdns_pcie_ep_of_match[] = {
-	{ .compatible = "cdns,cdns-pcie-ep" },
 
-	{ },
+int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
-};
-
-static int cdns_pcie_ep_probe(struct platform_device *pdev)
 {
-	struct device *dev = &pdev->dev;
+	struct device *dev = ep->pcie.dev;
+	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
-	struct cdns_pcie_ep *ep;
+	struct cdns_pcie *pcie = &ep->pcie;
-	struct cdns_pcie *pcie;
-	struct pci_epc *epc;
 	struct resource *res;
+	struct pci_epc *epc;
 	int ret;
-	int phy_count;
 
-	ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
-	if (!ep)
-		return -ENOMEM;
-
-	pcie = &ep->pcie;
 	pcie->is_rc = false;
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
@@ -474,19 +434,6 @@ static int cdns_pcie_ep_probe(struct platform_device *pdev)
 	if (!ep->ob_addr)
 		return -ENOMEM;
 
-	ret = cdns_pcie_init_phy(dev, pcie);
-	if (ret) {
-		dev_err(dev, "failed to init phy\n");
-		return ret;
-	}
-	platform_set_drvdata(pdev, pcie);
-	pm_runtime_enable(dev);
-	ret = pm_runtime_get_sync(dev);
-	if (ret < 0) {
-		dev_err(dev, "pm_runtime_get_sync() failed\n");
-		goto err_get_sync;
-	}
-
 	/* Disable all but function 0 (anyway BIT(0) is hardwired to 1). */
 	cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, BIT(0));
 
@@ -528,38 +475,5 @@ static int cdns_pcie_ep_probe(struct platform_device *pdev)
  err_init:
 	pm_runtime_put_sync(dev);
 
- err_get_sync:
-	pm_runtime_disable(dev);
-	cdns_pcie_disable_phy(pcie);
-	phy_count = pcie->phy_count;
-	while (phy_count--)
-		device_link_del(pcie->link[phy_count]);
-
 	return ret;
 }
-
-static void cdns_pcie_ep_shutdown(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct cdns_pcie *pcie = dev_get_drvdata(dev);
-	int ret;
-
-	ret = pm_runtime_put_sync(dev);
-	if (ret < 0)
-		dev_dbg(dev, "pm_runtime_put_sync failed\n");
-
-	pm_runtime_disable(dev);
-
-	cdns_pcie_disable_phy(pcie);
-}
-
-static struct platform_driver cdns_pcie_ep_driver = {
-	.driver = {
-		.name = "cdns-pcie-ep",
-		.of_match_table = cdns_pcie_ep_of_match,
-		.pm	= &cdns_pcie_pm_ops,
-	},
-	.probe = cdns_pcie_ep_probe,
-	.shutdown = cdns_pcie_ep_shutdown,
-};
-builtin_platform_driver(cdns_pcie_ep_driver);

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

@@ -11,33 +11,6 @@
 
 #include "pcie-cadence.h"
 
-/**
- * struct cdns_pcie_rc - private data for this PCIe Root Complex driver
- * @pcie: Cadence PCIe controller
- * @dev: pointer to PCIe device
- * @cfg_res: start/end offsets in the physical system memory to map PCI
- *           configuration space accesses
- * @bus_range: first/last buses behind the PCIe host controller
- * @cfg_base: IO mapped window to access the PCI configuration space of a
- *            single function at a time
- * @max_regions: maximum number of regions supported by the hardware
- * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
- *                translation (nbits sets into the "no BAR match" register)
- * @vendor_id: PCI vendor ID
- * @device_id: PCI device ID
- */
-struct cdns_pcie_rc {
-	struct cdns_pcie	pcie;
-	struct device		*dev;
-	struct resource		*cfg_res;
-	struct resource		*bus_range;
-	void __iomem		*cfg_base;
-	u32			max_regions;
-	u32			no_bar_nbits;
-	u16			vendor_id;
-	u16			device_id;
-};
-
 static void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 				      int where)
 {
@@ -92,11 +65,6 @@ static struct pci_ops cdns_pcie_host_ops = {
 	.write		= pci_generic_config_write,
 };
 
-static const struct of_device_id cdns_pcie_host_of_match[] = {
-	{ .compatible = "cdns,cdns-pcie-host" },
-
-	{ },
-};
 
 static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
 {
@@ -136,10 +104,10 @@ static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
 static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc)
 {
 	struct cdns_pcie *pcie = &rc->pcie;
-	struct resource *cfg_res = rc->cfg_res;
 	struct resource *mem_res = pcie->mem_res;
 	struct resource *bus_range = rc->bus_range;
-	struct device *dev = rc->dev;
+	struct resource *cfg_res = rc->cfg_res;
+	struct device *dev = pcie->dev;
 	struct device_node *np = dev->of_node;
 	struct of_pci_range_parser parser;
 	struct of_pci_range range;
@@ -233,25 +201,21 @@ static int cdns_pcie_host_init(struct device *dev,
 	return err;
 }
 
-static int cdns_pcie_host_probe(struct platform_device *pdev)
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 {
-	struct device *dev = &pdev->dev;
+	struct device *dev = rc->pcie.dev;
+	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
 	struct pci_host_bridge *bridge;
 	struct list_head resources;
-	struct cdns_pcie_rc *rc;
 	struct cdns_pcie *pcie;
 	struct resource *res;
 	int ret;
-	int phy_count;
 
-	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
+	bridge = pci_host_bridge_from_priv(rc);
 	if (!bridge)
 		return -ENOMEM;
 
-	rc = pci_host_bridge_priv(bridge);
-	rc->dev = dev;
-
 	pcie = &rc->pcie;
 	pcie->is_rc = true;
 
@@ -287,22 +251,9 @@ static int cdns_pcie_host_probe(struct platform_device *pdev)
 		dev_err(dev, "missing \"mem\"\n");
 		return -EINVAL;
 	}
+
 	pcie->mem_res = res;
 
-	ret = cdns_pcie_init_phy(dev, pcie);
-	if (ret) {
-		dev_err(dev, "failed to init phy\n");
-		return ret;
-	}
-	platform_set_drvdata(pdev, pcie);
-
-	pm_runtime_enable(dev);
-	ret = pm_runtime_get_sync(dev);
-	if (ret < 0) {
-		dev_err(dev, "pm_runtime_get_sync() failed\n");
-		goto err_get_sync;
-	}
-
 	ret = cdns_pcie_host_init(dev, &resources, rc);
 	if (ret)
 		goto err_init;
@@ -326,37 +277,5 @@ static int cdns_pcie_host_probe(struct platform_device *pdev)
  err_init:
 	pm_runtime_put_sync(dev);
 
- err_get_sync:
-	pm_runtime_disable(dev);
-	cdns_pcie_disable_phy(pcie);
-	phy_count = pcie->phy_count;
-	while (phy_count--)
-		device_link_del(pcie->link[phy_count]);
-
 	return ret;
 }
-
-static void cdns_pcie_shutdown(struct platform_device *pdev)
-{
-	struct device *dev = &pdev->dev;
-	struct cdns_pcie *pcie = dev_get_drvdata(dev);
-	int ret;
-
-	ret = pm_runtime_put_sync(dev);
-	if (ret < 0)
-		dev_dbg(dev, "pm_runtime_put_sync failed\n");
-
-	pm_runtime_disable(dev);
-	cdns_pcie_disable_phy(pcie);
-}
-
-static struct platform_driver cdns_pcie_host_driver = {
-	.driver = {
-		.name = "cdns-pcie-host",
-		.of_match_table = cdns_pcie_host_of_match,
-		.pm	= &cdns_pcie_pm_ops,
-	},
-	.probe = cdns_pcie_host_probe,
-	.shutdown = cdns_pcie_shutdown,
-};
-builtin_platform_driver(cdns_pcie_host_driver);

drivers/pci/controller/pcie-cadence-plat.c

@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence PCIe platform  driver.
+ *
+ * Copyright (c) 2019, Cadence Design Systems
+ * Author: Tom Joseph <tjoseph@cadence.com>
+ */
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+#include "pcie-cadence.h"
+
+/**
+ * struct cdns_plat_pcie - private data for this PCIe platform driver
+ * @pcie: Cadence PCIe controller
+ * @is_rc: Set to 1 indicates the PCIe controller mode is Root Complex,
+ *         if 0 it is in Endpoint mode.
+ */
+struct cdns_plat_pcie {
+	struct cdns_pcie        *pcie;
+	bool is_rc;
+};
+
+struct cdns_plat_pcie_of_data {
+	bool is_rc;
+};
+
+static const struct of_device_id cdns_plat_pcie_of_match[];
+
+static int cdns_plat_pcie_probe(struct platform_device *pdev)
+{
+	const struct cdns_plat_pcie_of_data *data;
+	struct cdns_plat_pcie *cdns_plat_pcie;
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	struct pci_host_bridge *bridge;
+	struct cdns_pcie_ep *ep;
+	struct cdns_pcie_rc *rc;
+	int phy_count;
+	bool is_rc;
+	int ret;
+
+	match = of_match_device(cdns_plat_pcie_of_match, dev);
+	if (!match)
+		return -EINVAL;
+
+	data = (struct cdns_plat_pcie_of_data *)match->data;
+	is_rc = data->is_rc;
+
+	pr_debug(" Started %s with is_rc: %d\n", __func__, is_rc);
+	cdns_plat_pcie = devm_kzalloc(dev, sizeof(*cdns_plat_pcie), GFP_KERNEL);
+	if (!cdns_plat_pcie)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, cdns_plat_pcie);
+	if (is_rc) {
+		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_HOST))
+			return -ENODEV;
+
+		bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
+		if (!bridge)
+			return -ENOMEM;
+
+		rc = pci_host_bridge_priv(bridge);
+		rc->pcie.dev = dev;
+		cdns_plat_pcie->pcie = &rc->pcie;
+		cdns_plat_pcie->is_rc = is_rc;
+
+		ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
+		if (ret) {
+			dev_err(dev, "failed to init phy\n");
+			return ret;
+		}
+		pm_runtime_enable(dev);
+		ret = pm_runtime_get_sync(dev);
+		if (ret < 0) {
+			dev_err(dev, "pm_runtime_get_sync() failed\n");
+			goto err_get_sync;
+		}
+
+		ret = cdns_pcie_host_setup(rc);
+		if (ret)
+			goto err_init;
+	} else {
+		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_PLAT_EP))
+			return -ENODEV;
+
+		ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
+		if (!ep)
+			return -ENOMEM;
+
+		ep->pcie.dev = dev;
+		cdns_plat_pcie->pcie = &ep->pcie;
+		cdns_plat_pcie->is_rc = is_rc;
+
+		ret = cdns_pcie_init_phy(dev, cdns_plat_pcie->pcie);
+		if (ret) {
+			dev_err(dev, "failed to init phy\n");
+			return ret;
+		}
+
+		pm_runtime_enable(dev);
+		ret = pm_runtime_get_sync(dev);
+		if (ret < 0) {
+			dev_err(dev, "pm_runtime_get_sync() failed\n");
+			goto err_get_sync;
+		}
+
+		ret = cdns_pcie_ep_setup(ep);
+		if (ret)
+			goto err_init;
+	}
+
+ err_init:
+	pm_runtime_put_sync(dev);
+
+ err_get_sync:
+	pm_runtime_disable(dev);
+	cdns_pcie_disable_phy(cdns_plat_pcie->pcie);
+	phy_count = cdns_plat_pcie->pcie->phy_count;
+	while (phy_count--)
+		device_link_del(cdns_plat_pcie->pcie->link[phy_count]);
+
+	return 0;
+}
+
+static void cdns_plat_pcie_shutdown(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cdns_pcie *pcie = dev_get_drvdata(dev);
+	int ret;
+
+	ret = pm_runtime_put_sync(dev);
+	if (ret < 0)
+		dev_dbg(dev, "pm_runtime_put_sync failed\n");
+
+	pm_runtime_disable(dev);
+
+	cdns_pcie_disable_phy(pcie);
+}
+
+static const struct cdns_plat_pcie_of_data cdns_plat_pcie_host_of_data = {
+	.is_rc = true,
+};
+
+static const struct cdns_plat_pcie_of_data cdns_plat_pcie_ep_of_data = {
+	.is_rc = false,
+};
+
+static const struct of_device_id cdns_plat_pcie_of_match[] = {
+	{
+		.compatible = "cdns,cdns-pcie-host",
+		.data = &cdns_plat_pcie_host_of_data,
+	},
+	{
+		.compatible = "cdns,cdns-pcie-ep",
+		.data = &cdns_plat_pcie_ep_of_data,
+	},
+	{},
+};
+
+static struct platform_driver cdns_plat_pcie_driver = {
+	.driver = {
+		.name = "cdns-pcie",
+		.of_match_table = cdns_plat_pcie_of_match,
+		.pm	= &cdns_pcie_pm_ops,
+	},
+	.probe = cdns_plat_pcie_probe,
+	.shutdown = cdns_plat_pcie_shutdown,
+};
+builtin_platform_driver(cdns_plat_pcie_driver);

drivers/pci/controller/pcie-cadence.h

@@ -190,6 +190,8 @@ enum cdns_pcie_rp_bar {
 	(((code) << 8) & CDNS_PCIE_NORMAL_MSG_CODE_MASK)
 #define CDNS_PCIE_MSG_NO_DATA			BIT(16)
 
+struct cdns_pcie;
+
 enum cdns_pcie_msg_code {
 	MSG_CODE_ASSERT_INTA	= 0x20,
 	MSG_CODE_ASSERT_INTB	= 0x21,
@@ -231,13 +233,71 @@ enum cdns_pcie_msg_routing {
 struct cdns_pcie {
 	void __iomem		*reg_base;
 	struct resource		*mem_res;
+	struct device		*dev;
 	bool			is_rc;
 	u8			bus;
 	int			phy_count;
 	struct phy		**phy;
 	struct device_link	**link;
+	const struct cdns_pcie_common_ops *ops;
 };
 
+/**
+ * struct cdns_pcie_rc - private data for this PCIe Root Complex driver
+ * @pcie: Cadence PCIe controller
+ * @dev: pointer to PCIe device
+ * @cfg_res: start/end offsets in the physical system memory to map PCI
+ *           configuration space accesses
+ * @bus_range: first/last buses behind the PCIe host controller
+ * @cfg_base: IO mapped window to access the PCI configuration space of a
+ *            single function at a time
+ * @max_regions: maximum number of regions supported by the hardware
+ * @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
+ *                translation (nbits sets into the "no BAR match" register)
+ * @vendor_id: PCI vendor ID
+ * @device_id: PCI device ID
+ */
+struct cdns_pcie_rc {
+	struct cdns_pcie	pcie;
+	struct resource		*cfg_res;
+	struct resource		*bus_range;
+	void __iomem		*cfg_base;
+	u32			max_regions;
+	u32			no_bar_nbits;
+	u16			vendor_id;
+	u16			device_id;
+};
+
+/**
+ * struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
+ * @pcie: Cadence PCIe controller
+ * @max_regions: maximum number of regions supported by hardware
+ * @ob_region_map: bitmask of mapped outbound regions
+ * @ob_addr: base addresses in the AXI bus where the outbound regions start
+ * @irq_phys_addr: base address on the AXI bus where the MSI/legacy IRQ
+ *		   dedicated outbound regions is mapped.
+ * @irq_cpu_addr: base address in the CPU space where a write access triggers
+ *		  the sending of a memory write (MSI) / normal message (legacy
+ *		  IRQ) TLP through the PCIe bus.
+ * @irq_pci_addr: used to save the current mapping of the MSI/legacy IRQ
+ *		  dedicated outbound region.
+ * @irq_pci_fn: the latest PCI function that has updated the mapping of
+ *		the MSI/legacy IRQ dedicated outbound region.
+ * @irq_pending: bitmask of asserted legacy IRQs.
+ */
+struct cdns_pcie_ep {
+	struct cdns_pcie	pcie;
+	u32			max_regions;
+	unsigned long		ob_region_map;
+	phys_addr_t		*ob_addr;
+	phys_addr_t		irq_phys_addr;
+	void __iomem		*irq_cpu_addr;
+	u64			irq_pci_addr;
+	u8			irq_pci_fn;
+	u8			irq_pending;
+};
+
+
 /* Register access */
 static inline void cdns_pcie_writeb(struct cdns_pcie *pcie, u32 reg, u8 value)
 {
@@ -306,6 +366,23 @@ static inline u32 cdns_pcie_ep_fn_readl(struct cdns_pcie *pcie, u8 fn, u32 reg)
 	return readl(pcie->reg_base + CDNS_PCIE_EP_FUNC_BASE(fn) + reg);
 }
 
+#ifdef CONFIG_PCIE_CADENCE_HOST
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
+#else
+static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_PCIE_CADENCE_EP
+int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep);
+#else
+static inline int cdns_pcie_ep_setup(struct cdns_pcie_ep *ep)
+{
+	return 0;
+}
+#endif
 void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 fn,
 				   u32 r, bool is_io,
 				   u64 cpu_addr, u64 pci_addr, size_t size);