1 files changed, 538 insertions, 0 deletions

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
new file mode 100644
index 000000000..2c32de667
--- /dev/null
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -0,0 +1,538 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * PCI Endpoint *Function* (EPF) library
+ *
+ * Copyright (C) 2017 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@ti.com>
+ */
+
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+#include <linux/pci-ep-cfs.h>
+
+static DEFINE_MUTEX(pci_epf_mutex);
+
+static struct bus_type pci_epf_bus_type;
+static const struct device_type pci_epf_type;
+
+/**
+ * pci_epf_unbind() - Notify the function driver that the binding between the
+ *		      EPF device and EPC device has been lost
+ * @epf: the EPF device which has lost the binding with the EPC device
+ *
+ * Invoke to notify the function driver that the binding between the EPF device
+ * and EPC device has been lost.
+ */
+void pci_epf_unbind(struct pci_epf *epf)
+{
+	struct pci_epf *epf_vf;
+
+	if (!epf->driver) {
+		dev_WARN(&epf->dev, "epf device not bound to driver\n");
+		return;
+	}
+
+	mutex_lock(&epf->lock);
+	list_for_each_entry(epf_vf, &epf->pci_vepf, list) {
+		if (epf_vf->is_bound)
+			epf_vf->driver->ops->unbind(epf_vf);
+	}
+	if (epf->is_bound)
+		epf->driver->ops->unbind(epf);
+	mutex_unlock(&epf->lock);
+	module_put(epf->driver->owner);
+}
+EXPORT_SYMBOL_GPL(pci_epf_unbind);
+
+/**
+ * pci_epf_bind() - Notify the function driver that the EPF device has been
+ *		    bound to a EPC device
+ * @epf: the EPF device which has been bound to the EPC device
+ *
+ * Invoke to notify the function driver that it has been bound to a EPC device
+ */
+int pci_epf_bind(struct pci_epf *epf)
+{
+	struct device *dev = &epf->dev;
+	struct pci_epf *epf_vf;
+	u8 func_no, vfunc_no;
+	struct pci_epc *epc;
+	int ret;
+
+	if (!epf->driver) {
+		dev_WARN(dev, "epf device not bound to driver\n");
+		return -EINVAL;
+	}
+
+	if (!try_module_get(epf->driver->owner))
+		return -EAGAIN;
+
+	mutex_lock(&epf->lock);
+	list_for_each_entry(epf_vf, &epf->pci_vepf, list) {
+		vfunc_no = epf_vf->vfunc_no;
+
+		if (vfunc_no < 1) {
+			dev_err(dev, "Invalid virtual function number\n");
+			ret = -EINVAL;
+			goto ret;
+		}
+
+		epc = epf->epc;
+		func_no = epf->func_no;
+		if (!IS_ERR_OR_NULL(epc)) {
+			if (!epc->max_vfs) {
+				dev_err(dev, "No support for virt function\n");
+				ret = -EINVAL;
+				goto ret;
+			}
+
+			if (vfunc_no > epc->max_vfs[func_no]) {
+				dev_err(dev, "PF%d: Exceeds max vfunc number\n",
+					func_no);
+				ret = -EINVAL;
+				goto ret;
+			}
+		}
+
+		epc = epf->sec_epc;
+		func_no = epf->sec_epc_func_no;
+		if (!IS_ERR_OR_NULL(epc)) {
+			if (!epc->max_vfs) {
+				dev_err(dev, "No support for virt function\n");
+				ret = -EINVAL;
+				goto ret;
+			}
+
+			if (vfunc_no > epc->max_vfs[func_no]) {
+				dev_err(dev, "PF%d: Exceeds max vfunc number\n",
+					func_no);
+				ret = -EINVAL;
+				goto ret;
+			}
+		}
+
+		epf_vf->func_no = epf->func_no;
+		epf_vf->sec_epc_func_no = epf->sec_epc_func_no;
+		epf_vf->epc = epf->epc;
+		epf_vf->sec_epc = epf->sec_epc;
+		ret = epf_vf->driver->ops->bind(epf_vf);
+		if (ret)
+			goto ret;
+		epf_vf->is_bound = true;
+	}
+
+	ret = epf->driver->ops->bind(epf);
+	if (ret)
+		goto ret;
+	epf->is_bound = true;
+
+	mutex_unlock(&epf->lock);
+	return 0;
+
+ret:
+	mutex_unlock(&epf->lock);
+	pci_epf_unbind(epf);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(pci_epf_bind);
+
+/**
+ * pci_epf_add_vepf() - associate virtual EP function to physical EP function
+ * @epf_pf: the physical EP function to which the virtual EP function should be
+ *   associated
+ * @epf_vf: the virtual EP function to be added
+ *
+ * A physical endpoint function can be associated with multiple virtual
+ * endpoint functions. Invoke pci_epf_add_epf() to add a virtual PCI endpoint
+ * function to a physical PCI endpoint function.
+ */
+int pci_epf_add_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)
+{
+	u32 vfunc_no;
+
+	if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))
+		return -EINVAL;
+
+	if (epf_pf->epc || epf_vf->epc || epf_vf->epf_pf)
+		return -EBUSY;
+
+	if (epf_pf->sec_epc || epf_vf->sec_epc)
+		return -EBUSY;
+
+	mutex_lock(&epf_pf->lock);
+	vfunc_no = find_first_zero_bit(&epf_pf->vfunction_num_map,
+				       BITS_PER_LONG);
+	if (vfunc_no >= BITS_PER_LONG) {
+		mutex_unlock(&epf_pf->lock);
+		return -EINVAL;
+	}
+
+	set_bit(vfunc_no, &epf_pf->vfunction_num_map);
+	epf_vf->vfunc_no = vfunc_no;
+
+	epf_vf->epf_pf = epf_pf;
+	epf_vf->is_vf = true;
+
+	list_add_tail(&epf_vf->list, &epf_pf->pci_vepf);
+	mutex_unlock(&epf_pf->lock);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(pci_epf_add_vepf);
+
+/**
+ * pci_epf_remove_vepf() - remove virtual EP function from physical EP function
+ * @epf_pf: the physical EP function from which the virtual EP function should
+ *   be removed
+ * @epf_vf: the virtual EP function to be removed
+ *
+ * Invoke to remove a virtual endpoint function from the physical endpoint
+ * function.
+ */
+void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)
+{
+	if (IS_ERR_OR_NULL(epf_pf) || IS_ERR_OR_NULL(epf_vf))
+		return;
+
+	mutex_lock(&epf_pf->lock);
+	clear_bit(epf_vf->vfunc_no, &epf_pf->vfunction_num_map);
+	list_del(&epf_vf->list);
+	mutex_unlock(&epf_pf->lock);
+}
+EXPORT_SYMBOL_GPL(pci_epf_remove_vepf);
+
+/**
+ * pci_epf_free_space() - free the allocated PCI EPF register space
+ * @epf: the EPF device from whom to free the memory
+ * @addr: the virtual address of the PCI EPF register space
+ * @bar: the BAR number corresponding to the register space
+ * @type: Identifies if the allocated space is for primary EPC or secondary EPC
+ *
+ * Invoke to free the allocated PCI EPF register space.
+ */
+void pci_epf_free_space(struct pci_epf *epf, void *addr, enum pci_barno bar,
+			enum pci_epc_interface_type type)
+{
+	struct device *dev;
+	struct pci_epf_bar *epf_bar;
+	struct pci_epc *epc;
+
+	if (!addr)
+		return;
+
+	if (type == PRIMARY_INTERFACE) {
+		epc = epf->epc;
+		epf_bar = epf->bar;
+	} else {
+		epc = epf->sec_epc;
+		epf_bar = epf->sec_epc_bar;
+	}
+
+	dev = epc->dev.parent;
+	dma_free_coherent(dev, epf_bar[bar].size, addr,
+			  epf_bar[bar].phys_addr);
+
+	epf_bar[bar].phys_addr = 0;
+	epf_bar[bar].addr = NULL;
+	epf_bar[bar].size = 0;
+	epf_bar[bar].barno = 0;
+	epf_bar[bar].flags = 0;
+}
+EXPORT_SYMBOL_GPL(pci_epf_free_space);
+
+/**
+ * pci_epf_alloc_space() - allocate memory for the PCI EPF register space
+ * @epf: the EPF device to whom allocate the memory
+ * @size: the size of the memory that has to be allocated
+ * @bar: the BAR number corresponding to the allocated register space
+ * @align: alignment size for the allocation region
+ * @type: Identifies if the allocation is for primary EPC or secondary EPC
+ *
+ * Invoke to allocate memory for the PCI EPF register space.
+ */
+void *pci_epf_alloc_space(struct pci_epf *epf, size_t size, enum pci_barno bar,
+			  size_t align, enum pci_epc_interface_type type)
+{
+	struct pci_epf_bar *epf_bar;
+	dma_addr_t phys_addr;
+	struct pci_epc *epc;
+	struct device *dev;
+	void *space;
+
+	if (size < 128)
+		size = 128;
+
+	if (align)
+		size = ALIGN(size, align);
+	else
+		size = roundup_pow_of_two(size);
+
+	if (type == PRIMARY_INTERFACE) {
+		epc = epf->epc;
+		epf_bar = epf->bar;
+	} else {
+		epc = epf->sec_epc;
+		epf_bar = epf->sec_epc_bar;
+	}
+
+	dev = epc->dev.parent;
+	space = dma_alloc_coherent(dev, size, &phys_addr, GFP_KERNEL);
+	if (!space) {
+		dev_err(dev, "failed to allocate mem space\n");
+		return NULL;
+	}
+
+	epf_bar[bar].phys_addr = phys_addr;
+	epf_bar[bar].addr = space;
+	epf_bar[bar].size = size;
+	epf_bar[bar].barno = bar;
+	epf_bar[bar].flags |= upper_32_bits(size) ?
+				PCI_BASE_ADDRESS_MEM_TYPE_64 :
+				PCI_BASE_ADDRESS_MEM_TYPE_32;
+
+	return space;
+}
+EXPORT_SYMBOL_GPL(pci_epf_alloc_space);
+
+static void pci_epf_remove_cfs(struct pci_epf_driver *driver)
+{
+	struct config_group *group, *tmp;
+
+	if (!IS_ENABLED(CONFIG_PCI_ENDPOINT_CONFIGFS))
+		return;
+
+	mutex_lock(&pci_epf_mutex);
+	list_for_each_entry_safe(group, tmp, &driver->epf_group, group_entry)
+		pci_ep_cfs_remove_epf_group(group);
+	list_del(&driver->epf_group);
+	mutex_unlock(&pci_epf_mutex);
+}
+
+/**
+ * pci_epf_unregister_driver() - unregister the PCI EPF driver
+ * @driver: the PCI EPF driver that has to be unregistered
+ *
+ * Invoke to unregister the PCI EPF driver.
+ */
+void pci_epf_unregister_driver(struct pci_epf_driver *driver)
+{
+	pci_epf_remove_cfs(driver);
+	driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(pci_epf_unregister_driver);
+
+static int pci_epf_add_cfs(struct pci_epf_driver *driver)
+{
+	struct config_group *group;
+	const struct pci_epf_device_id *id;
+
+	if (!IS_ENABLED(CONFIG_PCI_ENDPOINT_CONFIGFS))
+		return 0;
+
+	INIT_LIST_HEAD(&driver->epf_group);
+
+	id = driver->id_table;
+	while (id->name[0]) {
+		group = pci_ep_cfs_add_epf_group(id->name);
+		if (IS_ERR(group)) {
+			pci_epf_remove_cfs(driver);
+			return PTR_ERR(group);
+		}
+
+		mutex_lock(&pci_epf_mutex);
+		list_add_tail(&group->group_entry, &driver->epf_group);
+		mutex_unlock(&pci_epf_mutex);
+		id++;
+	}
+
+	return 0;
+}
+
+/**
+ * __pci_epf_register_driver() - register a new PCI EPF driver
+ * @driver: structure representing PCI EPF driver
+ * @owner: the owner of the module that registers the PCI EPF driver
+ *
+ * Invoke to register a new PCI EPF driver.
+ */
+int __pci_epf_register_driver(struct pci_epf_driver *driver,
+			      struct module *owner)
+{
+	int ret;
+
+	if (!driver->ops)
+		return -EINVAL;
+
+	if (!driver->ops->bind || !driver->ops->unbind)
+		return -EINVAL;
+
+	driver->driver.bus = &pci_epf_bus_type;
+	driver->driver.owner = owner;
+
+	ret = driver_register(&driver->driver);
+	if (ret)
+		return ret;
+
+	pci_epf_add_cfs(driver);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__pci_epf_register_driver);
+
+/**
+ * pci_epf_destroy() - destroy the created PCI EPF device
+ * @epf: the PCI EPF device that has to be destroyed.
+ *
+ * Invoke to destroy the PCI EPF device created by invoking pci_epf_create().
+ */
+void pci_epf_destroy(struct pci_epf *epf)
+{
+	device_unregister(&epf->dev);
+}
+EXPORT_SYMBOL_GPL(pci_epf_destroy);
+
+/**
+ * pci_epf_create() - create a new PCI EPF device
+ * @name: the name of the PCI EPF device. This name will be used to bind the
+ *	  EPF device to a EPF driver
+ *
+ * Invoke to create a new PCI EPF device by providing the name of the function
+ * device.
+ */
+struct pci_epf *pci_epf_create(const char *name)
+{
+	int ret;
+	struct pci_epf *epf;
+	struct device *dev;
+	int len;
+
+	epf = kzalloc(sizeof(*epf), GFP_KERNEL);
+	if (!epf)
+		return ERR_PTR(-ENOMEM);
+
+	len = strchrnul(name, '.') - name;
+	epf->name = kstrndup(name, len, GFP_KERNEL);
+	if (!epf->name) {
+		kfree(epf);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	/* VFs are numbered starting with 1. So set BIT(0) by default */
+	epf->vfunction_num_map = 1;
+	INIT_LIST_HEAD(&epf->pci_vepf);
+
+	dev = &epf->dev;
+	device_initialize(dev);
+	dev->bus = &pci_epf_bus_type;
+	dev->type = &pci_epf_type;
+	mutex_init(&epf->lock);
+
+	ret = dev_set_name(dev, "%s", name);
+	if (ret) {
+		put_device(dev);
+		return ERR_PTR(ret);
+	}
+
+	ret = device_add(dev);
+	if (ret) {
+		put_device(dev);
+		return ERR_PTR(ret);
+	}
+
+	return epf;
+}
+EXPORT_SYMBOL_GPL(pci_epf_create);
+
+static void pci_epf_dev_release(struct device *dev)
+{
+	struct pci_epf *epf = to_pci_epf(dev);
+
+	kfree(epf->name);
+	kfree(epf);
+}
+
+static const struct device_type pci_epf_type = {
+	.release	= pci_epf_dev_release,
+};
+
+static const struct pci_epf_device_id *
+pci_epf_match_id(const struct pci_epf_device_id *id, const struct pci_epf *epf)
+{
+	while (id->name[0]) {
+		if (strcmp(epf->name, id->name) == 0)
+			return id;
+		id++;
+	}
+
+	return NULL;
+}
+
+static int pci_epf_device_match(struct device *dev, struct device_driver *drv)
+{
+	struct pci_epf *epf = to_pci_epf(dev);
+	struct pci_epf_driver *driver = to_pci_epf_driver(drv);
+
+	if (driver->id_table)
+		return !!pci_epf_match_id(driver->id_table, epf);
+
+	return !strcmp(epf->name, drv->name);
+}
+
+static int pci_epf_device_probe(struct device *dev)
+{
+	struct pci_epf *epf = to_pci_epf(dev);
+	struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver);
+
+	if (!driver->probe)
+		return -ENODEV;
+
+	epf->driver = driver;
+
+	return driver->probe(epf, pci_epf_match_id(driver->id_table, epf));
+}
+
+static void pci_epf_device_remove(struct device *dev)
+{
+	struct pci_epf *epf = to_pci_epf(dev);
+	struct pci_epf_driver *driver = to_pci_epf_driver(dev->driver);
+
+	if (driver->remove)
+		driver->remove(epf);
+	epf->driver = NULL;
+}
+
+static struct bus_type pci_epf_bus_type = {
+	.name		= "pci-epf",
+	.match		= pci_epf_device_match,
+	.probe		= pci_epf_device_probe,
+	.remove		= pci_epf_device_remove,
+};
+
+static int __init pci_epf_init(void)
+{
+	int ret;
+
+	ret = bus_register(&pci_epf_bus_type);
+	if (ret) {
+		pr_err("failed to register pci epf bus --> %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+module_init(pci_epf_init);
+
+static void __exit pci_epf_exit(void)
+{
+	bus_unregister(&pci_epf_bus_type);
+}
+module_exit(pci_epf_exit);
+
+MODULE_DESCRIPTION("PCI EPF Library");
+MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");