OpenCloudOS-Kernel/drivers/pci/endpoint/pci-epc-core.c

588 lines
14 KiB
C

/**
* PCI Endpoint *Controller* (EPC) library
*
* Copyright (C) 2017 Texas Instruments
* Author: Kishon Vijay Abraham I <kishon@ti.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 of
* the License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/device.h>
#include <linux/dma-mapping.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_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)
{
unsigned long flags;
if (IS_ERR(epc) || !epc->ops->stop)
return;
spin_lock_irqsave(&epc->lock, flags);
epc->ops->stop(epc);
spin_unlock_irqrestore(&epc->lock, flags);
}
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;
unsigned long flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->start)
return 0;
spin_lock_irqsave(&epc->lock, flags);
ret = epc->ops->start(epc);
spin_unlock_irqrestore(&epc->lock, flags);
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
* @type: specify the type of interrupt; legacy or MSI
* @interrupt_num: the MSI interrupt number
*
* Invoke to raise an MSI or legacy interrupt
*/
int pci_epc_raise_irq(struct pci_epc *epc, enum pci_epc_irq_type type,
u8 interrupt_num)
{
int ret;
unsigned long flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->raise_irq)
return 0;
spin_lock_irqsave(&epc->lock, flags);
ret = epc->ops->raise_irq(epc, type, interrupt_num);
spin_unlock_irqrestore(&epc->lock, flags);
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
*
* Invoke to get the number of MSI interrupts allocated by the RC
*/
int pci_epc_get_msi(struct pci_epc *epc)
{
int interrupt;
unsigned long flags;
if (IS_ERR(epc))
return 0;
if (!epc->ops->get_msi)
return 0;
spin_lock_irqsave(&epc->lock, flags);
interrupt = epc->ops->get_msi(epc);
spin_unlock_irqrestore(&epc->lock, flags);
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
* @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 interrupts)
{
int ret;
u8 encode_int;
unsigned long flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->set_msi)
return 0;
encode_int = order_base_2(interrupts);
spin_lock_irqsave(&epc->lock, flags);
ret = epc->ops->set_msi(epc, encode_int);
spin_unlock_irqrestore(&epc->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(pci_epc_set_msi);
/**
* pci_epc_unmap_addr() - unmap CPU address from PCI address
* @epc: the EPC device on which address is allocated
* @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, phys_addr_t phys_addr)
{
unsigned long flags;
if (IS_ERR(epc))
return;
if (!epc->ops->unmap_addr)
return;
spin_lock_irqsave(&epc->lock, flags);
epc->ops->unmap_addr(epc, phys_addr);
spin_unlock_irqrestore(&epc->lock, flags);
}
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
* @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, phys_addr_t phys_addr,
u64 pci_addr, size_t size)
{
int ret;
unsigned long flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->map_addr)
return 0;
spin_lock_irqsave(&epc->lock, flags);
ret = epc->ops->map_addr(epc, phys_addr, pci_addr, size);
spin_unlock_irqrestore(&epc->lock, flags);
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
* @bar: the BAR number that has to be reset
*
* Invoke to reset the BAR of the endpoint device.
*/
void pci_epc_clear_bar(struct pci_epc *epc, int bar)
{
unsigned long flags;
if (IS_ERR(epc))
return;
if (!epc->ops->clear_bar)
return;
spin_lock_irqsave(&epc->lock, flags);
epc->ops->clear_bar(epc, bar);
spin_unlock_irqrestore(&epc->lock, flags);
}
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
* @bar: the BAR number that has to be configured
* @size: the size of the addr space
* @flags: specify memory allocation/io allocation/32bit address/64 bit address
*
* Invoke to configure the BAR of the endpoint device.
*/
int pci_epc_set_bar(struct pci_epc *epc, enum pci_barno bar,
dma_addr_t bar_phys, size_t size, int flags)
{
int ret;
unsigned long irq_flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->set_bar)
return 0;
spin_lock_irqsave(&epc->lock, irq_flags);
ret = epc->ops->set_bar(epc, bar, bar_phys, size, flags);
spin_unlock_irqrestore(&epc->lock, irq_flags);
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
* @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, struct pci_epf_header *header)
{
int ret;
unsigned long flags;
if (IS_ERR(epc))
return -EINVAL;
if (!epc->ops->write_header)
return 0;
spin_lock_irqsave(&epc->lock, flags);
ret = epc->ops->write_header(epc, header);
spin_unlock_irqrestore(&epc->lock, flags);
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)
{
unsigned long flags;
struct device *dev = epc->dev.parent;
if (epf->epc)
return -EBUSY;
if (IS_ERR(epc))
return -EINVAL;
if (epf->func_no > epc->max_functions - 1)
return -EINVAL;
epf->epc = epc;
if (dev->of_node) {
of_dma_configure(&epf->dev, dev->of_node);
} else {
dma_set_coherent_mask(&epf->dev, epc->dev.coherent_dma_mask);
epf->dev.dma_mask = epc->dev.dma_mask;
}
spin_lock_irqsave(&epc->lock, flags);
list_add_tail(&epf->list, &epc->pci_epf);
spin_unlock_irqrestore(&epc->lock, flags);
return 0;
}
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)
{
unsigned long flags;
if (!epc || IS_ERR(epc))
return;
spin_lock_irqsave(&epc->lock, flags);
list_del(&epf->list);
spin_unlock_irqrestore(&epc->lock, flags);
}
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)
{
unsigned long flags;
struct pci_epf *epf;
if (!epc || IS_ERR(epc))
return;
spin_lock_irqsave(&epc->lock, flags);
list_for_each_entry(epf, &epc->pci_epf, list)
pci_epf_linkup(epf);
spin_unlock_irqrestore(&epc->lock, flags);
}
EXPORT_SYMBOL_GPL(pci_epc_linkup);
/**
* 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;
}
spin_lock_init(&epc->lock);
INIT_LIST_HEAD(&epc->pci_epf);
device_initialize(&epc->dev);
dma_set_coherent_mask(&epc->dev, dev->coherent_dma_mask);
epc->dev.class = pci_epc_class;
epc->dev.dma_mask = dev->dma_mask;
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");