diff options
Diffstat (limited to 'drivers/pci/endpoint/pci-epc-core.c')
| -rw-r--r-- | drivers/pci/endpoint/pci-epc-core.c | 735 |
1 files changed, 735 insertions, 0 deletions
diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c new file mode 100644 index 000000000..ea7e7465c --- /dev/null +++ b/drivers/pci/endpoint/pci-epc-core.c @@ -0,0 +1,735 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI Endpoint *Controller* (EPC) library + * + * Copyright (C) 2017 Texas Instruments + * Author: Kishon Vijay Abraham I <kishon@ti.com> + */ + +#include <linux/device.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/of_device.h> + +#include <linux/pci-epc.h> +#include <linux/pci-epf.h> +#include <linux/pci-ep-cfs.h> + +static struct class *pci_epc_class; + +static void devm_pci_epc_release(struct device *dev, void *res) +{ + struct pci_epc *epc = *(struct pci_epc **)res; + + pci_epc_destroy(epc); +} + +static int devm_pci_epc_match(struct device *dev, void *res, void *match_data) +{ + struct pci_epc **epc = res; + + return *epc == match_data; +} + +/** + * pci_epc_put() - release the PCI endpoint controller + * @epc: epc returned by pci_epc_get() + * + * release the refcount the caller obtained by invoking pci_epc_get() + */ +void pci_epc_put(struct pci_epc *epc) +{ + if (!epc || IS_ERR(epc)) + return; + + module_put(epc->ops->owner); + put_device(&epc->dev); +} +EXPORT_SYMBOL_GPL(pci_epc_put); + +/** + * pci_epc_get() - get the PCI endpoint controller + * @epc_name: device name of the endpoint controller + * + * Invoke to get struct pci_epc * corresponding to the device name of the + * endpoint controller + */ +struct pci_epc *pci_epc_get(const char *epc_name) +{ + int ret = -EINVAL; + struct pci_epc *epc; + struct device *dev; + struct class_dev_iter iter; + + class_dev_iter_init(&iter, pci_epc_class, NULL, NULL); + while ((dev = class_dev_iter_next(&iter))) { + if (strcmp(epc_name, dev_name(dev))) + continue; + + epc = to_pci_epc(dev); + if (!try_module_get(epc->ops->owner)) { + ret = -EINVAL; + goto err; + } + + class_dev_iter_exit(&iter); + get_device(&epc->dev); + return epc; + } + +err: + class_dev_iter_exit(&iter); + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(pci_epc_get); + +/** + * pci_epc_get_first_free_bar() - helper to get first unreserved BAR + * @epc_features: pci_epc_features structure that holds the reserved bar bitmap + * + * Invoke to get the first unreserved BAR that can be used by the endpoint + * function. For any incorrect value in reserved_bar return '0'. + */ +enum pci_barno +pci_epc_get_first_free_bar(const struct pci_epc_features *epc_features) +{ + return pci_epc_get_next_free_bar(epc_features, BAR_0); +} +EXPORT_SYMBOL_GPL(pci_epc_get_first_free_bar); + +/** + * pci_epc_get_next_free_bar() - helper to get unreserved BAR starting from @bar + * @epc_features: pci_epc_features structure that holds the reserved bar bitmap + * @bar: the starting BAR number from where unreserved BAR should be searched + * + * Invoke to get the next unreserved BAR starting from @bar that can be used + * for endpoint function. For any incorrect value in reserved_bar return '0'. + */ +enum pci_barno pci_epc_get_next_free_bar(const struct pci_epc_features + *epc_features, enum pci_barno bar) +{ + unsigned long free_bar; + + if (!epc_features) + return BAR_0; + + /* If 'bar - 1' is a 64-bit BAR, move to the next BAR */ + if ((epc_features->bar_fixed_64bit << 1) & 1 << bar) + bar++; + + /* Find if the reserved BAR is also a 64-bit BAR */ + free_bar = epc_features->reserved_bar & epc_features->bar_fixed_64bit; + + /* Set the adjacent bit if the reserved BAR is also a 64-bit BAR */ + free_bar <<= 1; + free_bar |= epc_features->reserved_bar; + + free_bar = find_next_zero_bit(&free_bar, 6, bar); + if (free_bar > 5) + return NO_BAR; + + return free_bar; +} +EXPORT_SYMBOL_GPL(pci_epc_get_next_free_bar); + +/** + * pci_epc_get_features() - get the features supported by EPC + * @epc: the features supported by *this* EPC device will be returned + * @func_no: the features supported by the EPC device specific to the + * endpoint function with func_no will be returned + * + * Invoke to get the features provided by the EPC which may be + * specific to an endpoint function. Returns pci_epc_features on success + * and NULL for any failures. + */ +const struct pci_epc_features *pci_epc_get_features(struct pci_epc *epc, + u8 func_no) +{ + const struct pci_epc_features *epc_features; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return NULL; + + if (!epc->ops->get_features) + return NULL; + + mutex_lock(&epc->lock); + epc_features = epc->ops->get_features(epc, func_no); + mutex_unlock(&epc->lock); + + return epc_features; +} +EXPORT_SYMBOL_GPL(pci_epc_get_features); + +/** + * pci_epc_stop() - stop the PCI link + * @epc: the link of the EPC device that has to be stopped + * + * Invoke to stop the PCI link + */ +void pci_epc_stop(struct pci_epc *epc) +{ + if (IS_ERR(epc) || !epc->ops->stop) + return; + + mutex_lock(&epc->lock); + epc->ops->stop(epc); + mutex_unlock(&epc->lock); +} +EXPORT_SYMBOL_GPL(pci_epc_stop); + +/** + * pci_epc_start() - start the PCI link + * @epc: the link of *this* EPC device has to be started + * + * Invoke to start the PCI link + */ +int pci_epc_start(struct pci_epc *epc) +{ + int ret; + + if (IS_ERR(epc)) + return -EINVAL; + + if (!epc->ops->start) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->start(epc); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_start); + +/** + * pci_epc_raise_irq() - interrupt the host system + * @epc: the EPC device which has to interrupt the host + * @func_no: the endpoint function number in the EPC device + * @type: specify the type of interrupt; legacy, MSI or MSI-X + * @interrupt_num: the MSI or MSI-X interrupt number + * + * Invoke to raise an legacy, MSI or MSI-X interrupt + */ +int pci_epc_raise_irq(struct pci_epc *epc, u8 func_no, + enum pci_epc_irq_type type, u16 interrupt_num) +{ + int ret; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return -EINVAL; + + if (!epc->ops->raise_irq) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->raise_irq(epc, func_no, type, interrupt_num); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_raise_irq); + +/** + * pci_epc_get_msi() - get the number of MSI interrupt numbers allocated + * @epc: the EPC device to which MSI interrupts was requested + * @func_no: the endpoint function number in the EPC device + * + * Invoke to get the number of MSI interrupts allocated by the RC + */ +int pci_epc_get_msi(struct pci_epc *epc, u8 func_no) +{ + int interrupt; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return 0; + + if (!epc->ops->get_msi) + return 0; + + mutex_lock(&epc->lock); + interrupt = epc->ops->get_msi(epc, func_no); + mutex_unlock(&epc->lock); + + if (interrupt < 0) + return 0; + + interrupt = 1 << interrupt; + + return interrupt; +} +EXPORT_SYMBOL_GPL(pci_epc_get_msi); + +/** + * pci_epc_set_msi() - set the number of MSI interrupt numbers required + * @epc: the EPC device on which MSI has to be configured + * @func_no: the endpoint function number in the EPC device + * @interrupts: number of MSI interrupts required by the EPF + * + * Invoke to set the required number of MSI interrupts. + */ +int pci_epc_set_msi(struct pci_epc *epc, u8 func_no, u8 interrupts) +{ + int ret; + u8 encode_int; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || + interrupts > 32) + return -EINVAL; + + if (!epc->ops->set_msi) + return 0; + + encode_int = order_base_2(interrupts); + + mutex_lock(&epc->lock); + ret = epc->ops->set_msi(epc, func_no, encode_int); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_set_msi); + +/** + * pci_epc_get_msix() - get the number of MSI-X interrupt numbers allocated + * @epc: the EPC device to which MSI-X interrupts was requested + * @func_no: the endpoint function number in the EPC device + * + * Invoke to get the number of MSI-X interrupts allocated by the RC + */ +int pci_epc_get_msix(struct pci_epc *epc, u8 func_no) +{ + int interrupt; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return 0; + + if (!epc->ops->get_msix) + return 0; + + mutex_lock(&epc->lock); + interrupt = epc->ops->get_msix(epc, func_no); + mutex_unlock(&epc->lock); + + if (interrupt < 0) + return 0; + + return interrupt + 1; +} +EXPORT_SYMBOL_GPL(pci_epc_get_msix); + +/** + * pci_epc_set_msix() - set the number of MSI-X interrupt numbers required + * @epc: the EPC device on which MSI-X has to be configured + * @func_no: the endpoint function number in the EPC device + * @interrupts: number of MSI-X interrupts required by the EPF + * @bir: BAR where the MSI-X table resides + * @offset: Offset pointing to the start of MSI-X table + * + * Invoke to set the required number of MSI-X interrupts. + */ +int pci_epc_set_msix(struct pci_epc *epc, u8 func_no, u16 interrupts, + enum pci_barno bir, u32 offset) +{ + int ret; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || + interrupts < 1 || interrupts > 2048) + return -EINVAL; + + if (!epc->ops->set_msix) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->set_msix(epc, func_no, interrupts - 1, bir, offset); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_set_msix); + +/** + * pci_epc_unmap_addr() - unmap CPU address from PCI address + * @epc: the EPC device on which address is allocated + * @func_no: the endpoint function number in the EPC device + * @phys_addr: physical address of the local system + * + * Invoke to unmap the CPU address from PCI address. + */ +void pci_epc_unmap_addr(struct pci_epc *epc, u8 func_no, + phys_addr_t phys_addr) +{ + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return; + + if (!epc->ops->unmap_addr) + return; + + mutex_lock(&epc->lock); + epc->ops->unmap_addr(epc, func_no, phys_addr); + mutex_unlock(&epc->lock); +} +EXPORT_SYMBOL_GPL(pci_epc_unmap_addr); + +/** + * pci_epc_map_addr() - map CPU address to PCI address + * @epc: the EPC device on which address is allocated + * @func_no: the endpoint function number in the EPC device + * @phys_addr: physical address of the local system + * @pci_addr: PCI address to which the physical address should be mapped + * @size: the size of the allocation + * + * Invoke to map CPU address with PCI address. + */ +int pci_epc_map_addr(struct pci_epc *epc, u8 func_no, + phys_addr_t phys_addr, u64 pci_addr, size_t size) +{ + int ret; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return -EINVAL; + + if (!epc->ops->map_addr) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->map_addr(epc, func_no, phys_addr, pci_addr, size); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_map_addr); + +/** + * pci_epc_clear_bar() - reset the BAR + * @epc: the EPC device for which the BAR has to be cleared + * @func_no: the endpoint function number in the EPC device + * @epf_bar: the struct epf_bar that contains the BAR information + * + * Invoke to reset the BAR of the endpoint device. + */ +void pci_epc_clear_bar(struct pci_epc *epc, u8 func_no, + struct pci_epf_bar *epf_bar) +{ + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || + (epf_bar->barno == BAR_5 && + epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64)) + return; + + if (!epc->ops->clear_bar) + return; + + mutex_lock(&epc->lock); + epc->ops->clear_bar(epc, func_no, epf_bar); + mutex_unlock(&epc->lock); +} +EXPORT_SYMBOL_GPL(pci_epc_clear_bar); + +/** + * pci_epc_set_bar() - configure BAR in order for host to assign PCI addr space + * @epc: the EPC device on which BAR has to be configured + * @func_no: the endpoint function number in the EPC device + * @epf_bar: the struct epf_bar that contains the BAR information + * + * Invoke to configure the BAR of the endpoint device. + */ +int pci_epc_set_bar(struct pci_epc *epc, u8 func_no, + struct pci_epf_bar *epf_bar) +{ + int ret; + int flags = epf_bar->flags; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions || + (epf_bar->barno == BAR_5 && + flags & PCI_BASE_ADDRESS_MEM_TYPE_64) || + (flags & PCI_BASE_ADDRESS_SPACE_IO && + flags & PCI_BASE_ADDRESS_IO_MASK) || + (upper_32_bits(epf_bar->size) && + !(flags & PCI_BASE_ADDRESS_MEM_TYPE_64))) + return -EINVAL; + + if (!epc->ops->set_bar) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->set_bar(epc, func_no, epf_bar); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_set_bar); + +/** + * pci_epc_write_header() - write standard configuration header + * @epc: the EPC device to which the configuration header should be written + * @func_no: the endpoint function number in the EPC device + * @header: standard configuration header fields + * + * Invoke to write the configuration header to the endpoint controller. Every + * endpoint controller will have a dedicated location to which the standard + * configuration header would be written. The callback function should write + * the header fields to this dedicated location. + */ +int pci_epc_write_header(struct pci_epc *epc, u8 func_no, + struct pci_epf_header *header) +{ + int ret; + + if (IS_ERR_OR_NULL(epc) || func_no >= epc->max_functions) + return -EINVAL; + + if (!epc->ops->write_header) + return 0; + + mutex_lock(&epc->lock); + ret = epc->ops->write_header(epc, func_no, header); + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_write_header); + +/** + * pci_epc_add_epf() - bind PCI endpoint function to an endpoint controller + * @epc: the EPC device to which the endpoint function should be added + * @epf: the endpoint function to be added + * + * A PCI endpoint device can have one or more functions. In the case of PCIe, + * the specification allows up to 8 PCIe endpoint functions. Invoke + * pci_epc_add_epf() to add a PCI endpoint function to an endpoint controller. + */ +int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf) +{ + u32 func_no; + int ret = 0; + + if (epf->epc) + return -EBUSY; + + if (IS_ERR(epc)) + return -EINVAL; + + mutex_lock(&epc->lock); + func_no = find_first_zero_bit(&epc->function_num_map, + BITS_PER_LONG); + if (func_no >= BITS_PER_LONG) { + ret = -EINVAL; + goto ret; + } + + if (func_no > epc->max_functions - 1) { + dev_err(&epc->dev, "Exceeding max supported Function Number\n"); + ret = -EINVAL; + goto ret; + } + + set_bit(func_no, &epc->function_num_map); + epf->func_no = func_no; + epf->epc = epc; + + list_add_tail(&epf->list, &epc->pci_epf); + +ret: + mutex_unlock(&epc->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pci_epc_add_epf); + +/** + * pci_epc_remove_epf() - remove PCI endpoint function from endpoint controller + * @epc: the EPC device from which the endpoint function should be removed + * @epf: the endpoint function to be removed + * + * Invoke to remove PCI endpoint function from the endpoint controller. + */ +void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf) +{ + if (!epc || IS_ERR(epc) || !epf) + return; + + mutex_lock(&epc->lock); + clear_bit(epf->func_no, &epc->function_num_map); + list_del(&epf->list); + epf->epc = NULL; + mutex_unlock(&epc->lock); +} +EXPORT_SYMBOL_GPL(pci_epc_remove_epf); + +/** + * pci_epc_linkup() - Notify the EPF device that EPC device has established a + * connection with the Root Complex. + * @epc: the EPC device which has established link with the host + * + * Invoke to Notify the EPF device that the EPC device has established a + * connection with the Root Complex. + */ +void pci_epc_linkup(struct pci_epc *epc) +{ + if (!epc || IS_ERR(epc)) + return; + + atomic_notifier_call_chain(&epc->notifier, LINK_UP, NULL); +} +EXPORT_SYMBOL_GPL(pci_epc_linkup); + +/** + * pci_epc_init_notify() - Notify the EPF device that EPC device's core + * initialization is completed. + * @epc: the EPC device whose core initialization is completeds + * + * Invoke to Notify the EPF device that the EPC device's initialization + * is completed. + */ +void pci_epc_init_notify(struct pci_epc *epc) +{ + if (!epc || IS_ERR(epc)) + return; + + atomic_notifier_call_chain(&epc->notifier, CORE_INIT, NULL); +} +EXPORT_SYMBOL_GPL(pci_epc_init_notify); + +/** + * pci_epc_destroy() - destroy the EPC device + * @epc: the EPC device that has to be destroyed + * + * Invoke to destroy the PCI EPC device + */ +void pci_epc_destroy(struct pci_epc *epc) +{ + pci_ep_cfs_remove_epc_group(epc->group); + device_unregister(&epc->dev); + kfree(epc); +} +EXPORT_SYMBOL_GPL(pci_epc_destroy); + +/** + * devm_pci_epc_destroy() - destroy the EPC device + * @dev: device that wants to destroy the EPC + * @epc: the EPC device that has to be destroyed + * + * Invoke to destroy the devres associated with this + * pci_epc and destroy the EPC device. + */ +void devm_pci_epc_destroy(struct device *dev, struct pci_epc *epc) +{ + int r; + + r = devres_destroy(dev, devm_pci_epc_release, devm_pci_epc_match, + epc); + dev_WARN_ONCE(dev, r, "couldn't find PCI EPC resource\n"); +} +EXPORT_SYMBOL_GPL(devm_pci_epc_destroy); + +/** + * __pci_epc_create() - create a new endpoint controller (EPC) device + * @dev: device that is creating the new EPC + * @ops: function pointers for performing EPC operations + * @owner: the owner of the module that creates the EPC device + * + * Invoke to create a new EPC device and add it to pci_epc class. + */ +struct pci_epc * +__pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, + struct module *owner) +{ + int ret; + struct pci_epc *epc; + + if (WARN_ON(!dev)) { + ret = -EINVAL; + goto err_ret; + } + + epc = kzalloc(sizeof(*epc), GFP_KERNEL); + if (!epc) { + ret = -ENOMEM; + goto err_ret; + } + + mutex_init(&epc->lock); + INIT_LIST_HEAD(&epc->pci_epf); + ATOMIC_INIT_NOTIFIER_HEAD(&epc->notifier); + + device_initialize(&epc->dev); + epc->dev.class = pci_epc_class; + epc->dev.parent = dev; + epc->ops = ops; + + ret = dev_set_name(&epc->dev, "%s", dev_name(dev)); + if (ret) + goto put_dev; + + ret = device_add(&epc->dev); + if (ret) + goto put_dev; + + epc->group = pci_ep_cfs_add_epc_group(dev_name(dev)); + + return epc; + +put_dev: + put_device(&epc->dev); + kfree(epc); + +err_ret: + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(__pci_epc_create); + +/** + * __devm_pci_epc_create() - create a new endpoint controller (EPC) device + * @dev: device that is creating the new EPC + * @ops: function pointers for performing EPC operations + * @owner: the owner of the module that creates the EPC device + * + * Invoke to create a new EPC device and add it to pci_epc class. + * While at that, it also associates the device with the pci_epc using devres. + * On driver detach, release function is invoked on the devres data, + * then, devres data is freed. + */ +struct pci_epc * +__devm_pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, + struct module *owner) +{ + struct pci_epc **ptr, *epc; + + ptr = devres_alloc(devm_pci_epc_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + epc = __pci_epc_create(dev, ops, owner); + if (!IS_ERR(epc)) { + *ptr = epc; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return epc; +} +EXPORT_SYMBOL_GPL(__devm_pci_epc_create); + +static int __init pci_epc_init(void) +{ + pci_epc_class = class_create(THIS_MODULE, "pci_epc"); + if (IS_ERR(pci_epc_class)) { + pr_err("failed to create pci epc class --> %ld\n", + PTR_ERR(pci_epc_class)); + return PTR_ERR(pci_epc_class); + } + + return 0; +} +module_init(pci_epc_init); + +static void __exit pci_epc_exit(void) +{ + class_destroy(pci_epc_class); +} +module_exit(pci_epc_exit); + +MODULE_DESCRIPTION("PCI EPC Library"); +MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>"); +MODULE_LICENSE("GPL v2"); |