- 根目录:
- drivers
- pci
- pcie
- portdrv_core.c
/*
* File: portdrv_core.c
* Purpose: PCI Express Port Bus Driver's Core Functions
*
* Copyright (C) 2004 Intel
* Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/pm.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/pcieport_if.h>
#include <linux/aer.h>
#include "../pci.h"
#include "portdrv.h"
bool pciehp_msi_disabled;
static int __init pciehp_setup(char *str)
{
if (!strncmp(str, "nomsi", 5))
pciehp_msi_disabled = true;
return 1;
}
__setup("pcie_hp=", pciehp_setup);
/**
* release_pcie_device - free PCI Express port service device structure
* @dev: Port service device to release
*
* Invoked automatically when device is being removed in response to
* device_unregister(dev). Release all resources being claimed.
*/
static void release_pcie_device(struct device *dev)
{
kfree(to_pcie_device(dev));
}
/**
* pcie_port_msix_add_entry - add entry to given array of MSI-X entries
* @entries: Array of MSI-X entries
* @new_entry: Index of the entry to add to the array
* @nr_entries: Number of entries already in the array
*
* Return value: Position of the added entry in the array
*/
static int pcie_port_msix_add_entry(
struct msix_entry *entries, int new_entry, int nr_entries)
{
int j;
for (j = 0; j < nr_entries; j++)
if (entries[j].entry == new_entry)
return j;
entries[j].entry = new_entry;
return j;
}
/**
* pcie_port_enable_msix - try to set up MSI-X as interrupt mode for given port
* @dev: PCI Express port to handle
* @vectors: Array of interrupt vectors to populate
* @mask: Bitmask of port capabilities returned by get_port_device_capability()
*
* Return value: 0 on success, error code on failure
*/
static int pcie_port_enable_msix(struct pci_dev *dev, int *vectors, int mask)
{
struct msix_entry *msix_entries;
int idx[PCIE_PORT_DEVICE_MAXSERVICES];
int nr_entries, status, pos, i, nvec;
u16 reg16;
u32 reg32;
nr_entries = pci_msix_vec_count(dev);
if (nr_entries < 0)
return nr_entries;
BUG_ON(!nr_entries);
if (nr_entries > PCIE_PORT_MAX_MSIX_ENTRIES)
nr_entries = PCIE_PORT_MAX_MSIX_ENTRIES;
msix_entries = kzalloc(sizeof(*msix_entries) * nr_entries, GFP_KERNEL);
if (!msix_entries)
return -ENOMEM;
/*
* Allocate as many entries as the port wants, so that we can check
* which of them will be useful. Moreover, if nr_entries is correctly
* equal to the number of entries this port actually uses, we'll happily
* go through without any tricks.
*/
for (i = 0; i < nr_entries; i++)
msix_entries[i].entry = i;
status = pci_enable_msix(dev, msix_entries, nr_entries);
if (status)
goto Exit;
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
idx[i] = -1;
status = -EIO;
nvec = 0;
if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP)) {
int entry;
/*
* The code below follows the PCI Express Base Specification 2.0
* stating in Section 6.1.6 that "PME and Hot-Plug Event
* interrupts (when both are implemented) always share the same
* MSI or MSI-X vector, as indicated by the Interrupt Message
* Number field in the PCI Express Capabilities register", where
* according to Section 7.8.2 of the specification "For MSI-X,
* the value in this field indicates which MSI-X Table entry is
* used to generate the interrupt message."
*/
pcie_capability_read_word(dev, PCI_EXP_FLAGS, ®16);
entry = (reg16 & PCI_EXP_FLAGS_IRQ) >> 9;
if (entry >= nr_entries)
goto Error;
i = pcie_port_msix_add_entry(msix_entries, entry, nvec);
if (i == nvec)
nvec++;
idx[PCIE_PORT_SERVICE_PME_SHIFT] = i;
idx[PCIE_PORT_SERVICE_HP_SHIFT] = i;
}
if (mask & PCIE_PORT_SERVICE_AER) {
int entry;
/*
* The code below follows Section 7.10.10 of the PCI Express
* Base Specification 2.0 stating that bits 31-27 of the Root
* Error Status Register contain a value indicating which of the
* MSI/MSI-X vectors assigned to the port is going to be used
* for AER, where "For MSI-X, the value in this register
* indicates which MSI-X Table entry is used to generate the
* interrupt message."
*/
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR);
pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, ®32);
entry = reg32 >> 27;
if (entry >= nr_entries)
goto Error;
i = pcie_port_msix_add_entry(msix_entries, entry, nvec);
if (i == nvec)
nvec++;
idx[PCIE_PORT_SERVICE_AER_SHIFT] = i;
}
/*
* If nvec is equal to the allocated number of entries, we can just use
* what we have. Otherwise, the port has some extra entries not for the
* services we know and we need to work around that.
*/
if (nvec == nr_entries) {
status = 0;
} else {
/* Drop the temporary MSI-X setup */
pci_disable_msix(dev);
/* Now allocate the MSI-X vectors for real */
status = pci_enable_msix(dev, msix_entries, nvec);
if (status)
goto Exit;
}
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
vectors[i] = idx[i] >= 0 ? msix_entries[idx[i]].vector : -1;
Exit:
kfree(msix_entries);
return status;
Error:
pci_disable_msix(dev);
goto Exit;
}
/**
* init_service_irqs - initialize irqs for PCI Express port services
* @dev: PCI Express port to handle
* @irqs: Array of irqs to populate
* @mask: Bitmask of port capabilities returned by get_port_device_capability()
*
* Return value: Interrupt mode associated with the port
*/
static int init_service_irqs(struct pci_dev *dev, int *irqs, int mask)
{
int i, irq = -1;
/*
* If MSI cannot be used for PCIe PME or hotplug, we have to use
* INTx or other interrupts, e.g. system shared interrupt.
*/
if (((mask & PCIE_PORT_SERVICE_PME) && pcie_pme_no_msi()) ||
((mask & PCIE_PORT_SERVICE_HP) && pciehp_no_msi())) {
if (dev->irq)
irq = dev->irq;
goto no_msi;
}
/* Try to use MSI-X if supported */
if (!pcie_port_enable_msix(dev, irqs, mask))
return 0;
/*
* We're not going to use MSI-X, so try MSI and fall back to INTx.
* If neither MSI/MSI-X nor INTx available, try other interrupt. On
* some platforms, root port doesn't support MSI/MSI-X/INTx in RC mode.
*/
if (!pci_enable_msi(dev) || dev->irq)
irq = dev->irq;
no_msi:
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
irqs[i] = irq;
irqs[PCIE_PORT_SERVICE_VC_SHIFT] = -1;
if (irq < 0)
return -ENODEV;
return 0;
}
static void cleanup_service_irqs(struct pci_dev *dev)
{
if (dev->msix_enabled)
pci_disable_msix(dev);
else if (dev->msi_enabled)
pci_disable_msi(dev);
}
/**
* get_port_device_capability - discover capabilities of a PCI Express port
* @dev: PCI Express port to examine
*
* The capabilities are read from the port's PCI Express configuration registers
* as described in PCI Express Base Specification 1.0a sections 7.8.2, 7.8.9 and
* 7.9 - 7.11.
*
* Return value: Bitmask of discovered port capabilities
*/
static int get_port_device_capability(struct pci_dev *dev)
{
int services = 0;
u32 reg32;
int cap_mask = 0;
int err;
if (pcie_ports_disabled)
return 0;
cap_mask = PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP
| PCIE_PORT_SERVICE_VC;
if (pci_aer_available())
cap_mask |= PCIE_PORT_SERVICE_AER;
if (pcie_ports_auto) {
err = pcie_port_platform_notify(dev, &cap_mask);
if (err)
return 0;
}
/* Hot-Plug Capable */
if ((cap_mask & PCIE_PORT_SERVICE_HP) &&
pcie_caps_reg(dev) & PCI_EXP_FLAGS_SLOT) {
pcie_capability_read_dword(dev, PCI_EXP_SLTCAP, ®32);
if (reg32 & PCI_EXP_SLTCAP_HPC) {
services |= PCIE_PORT_SERVICE_HP;
/*
* Disable hot-plug interrupts in case they have been
* enabled by the BIOS and the hot-plug service driver
* is not loaded.
*/
pcie_capability_clear_word(dev, PCI_EXP_SLTCTL,
PCI_EXP_SLTCTL_CCIE | PCI_EXP_SLTCTL_HPIE);
}
}
/* AER capable */
if ((cap_mask & PCIE_PORT_SERVICE_AER)
&& pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR)) {
services |= PCIE_PORT_SERVICE_AER;
/*
* Disable AER on this port in case it's been enabled by the
* BIOS (the AER service driver will enable it when necessary).
*/
pci_disable_pcie_error_reporting(dev);
}
/* VC support */
if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_VC))
services |= PCIE_PORT_SERVICE_VC;
/* Root ports are capable of generating PME too */
if ((cap_mask & PCIE_PORT_SERVICE_PME)
&& pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) {
services |= PCIE_PORT_SERVICE_PME;
/*
* Disable PME interrupt on this port in case it's been enabled
* by the BIOS (the PME service driver will enable it when
* necessary).
*/
pcie_pme_interrupt_enable(dev, false);
}
return services;
}
/**
* pcie_device_init - allocate and initialize PCI Express port service device
* @pdev: PCI Express port to associate the service device with
* @service: Type of service to associate with the service device
* @irq: Interrupt vector to associate with the service device
*/
static int pcie_device_init(struct pci_dev *pdev, int service, int irq)
{
int retval;
struct pcie_device *pcie;
struct device *device;
pcie = kzalloc(sizeof(*pcie), GFP_KERNEL);
if (!pcie)
return -ENOMEM;
pcie->port = pdev;
pcie->irq = irq;
pcie->service = service;
/* Initialize generic device interface */
device = &pcie->device;
device->bus = &pcie_port_bus_type;
device->release = release_pcie_device; /* callback to free pcie dev */
dev_set_name(device, "%s:pcie%02x",
pci_name(pdev),
get_descriptor_id(pci_pcie_type(pdev), service));
device->parent = &pdev->dev;
device_enable_async_suspend(device);
retval = device_register(device);
if (retval) {
put_device(device);
return retval;
}
return 0;
}
/**
* pcie_port_device_register - register PCI Express port
* @dev: PCI Express port to register
*
* Allocate the port extension structure and register services associated with
* the port.
*/
int pcie_port_device_register(struct pci_dev *dev)
{
int status, capabilities, i, nr_service;
int irqs[PCIE_PORT_DEVICE_MAXSERVICES];
/* Enable PCI Express port device */
status = pci_enable_device(dev);
if (status)
return status;
/* Get and check PCI Express port services */
capabilities = get_port_device_capability(dev);
if (!capabilities)
return 0;
pci_set_master(dev);
/*
* Initialize service irqs. Don't use service devices that
* require interrupts if there is no way to generate them.
*/
status = init_service_irqs(dev, irqs, capabilities);
if (status) {
capabilities &= PCIE_PORT_SERVICE_VC;
if (!capabilities)
goto error_disable;
}
/* Allocate child services if any */
status = -ENODEV;
nr_service = 0;
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
int service = 1 << i;
if (!(capabilities & service))
continue;
if (!pcie_device_init(dev, service, irqs[i]))
nr_service++;
}
if (!nr_service)
goto error_cleanup_irqs;
return 0;
error_cleanup_irqs:
cleanup_service_irqs(dev);
error_disable:
pci_disable_device(dev);
return status;
}
#ifdef CONFIG_PM
static int suspend_iter(struct device *dev, void *data)
{
struct pcie_port_service_driver *service_driver;
if ((dev->bus == &pcie_port_bus_type) && dev->driver) {
service_driver = to_service_driver(dev->driver);
if (service_driver->suspend)
service_driver->suspend(to_pcie_device(dev));
}
return 0;
}
/**
* pcie_port_device_suspend - suspend port services associated with a PCIe port
* @dev: PCI Express port to handle
*/
int pcie_port_device_suspend(struct device *dev)
{
return device_for_each_child(dev, NULL, suspend_iter);
}
static int resume_iter(struct device *dev, void *data)
{
struct pcie_port_service_driver *service_driver;
if ((dev->bus == &pcie_port_bus_type) &&
(dev->driver)) {
service_driver = to_service_driver(dev->driver);
if (service_driver->resume)
service_driver->resume(to_pcie_device(dev));
}
return 0;
}
/**
* pcie_port_device_suspend - resume port services associated with a PCIe port
* @dev: PCI Express port to handle
*/
int pcie_port_device_resume(struct device *dev)
{
return device_for_each_child(dev, NULL, resume_iter);
}
#endif /* PM */
static int remove_iter(struct device *dev, void *data)
{
if (dev->bus == &pcie_port_bus_type)
device_unregister(dev);
return 0;
}
/**
* pcie_port_device_remove - unregister PCI Express port service devices
* @dev: PCI Express port the service devices to unregister are associated with
*
* Remove PCI Express port service devices associated with given port and
* disable MSI-X or MSI for the port.
*/
void pcie_port_device_remove(struct pci_dev *dev)
{
device_for_each_child(&dev->dev, NULL, remove_iter);
cleanup_service_irqs(dev);
pci_disable_device(dev);
}
/**
* pcie_port_probe_service - probe driver for given PCI Express port service
* @dev: PCI Express port service device to probe against
*
* If PCI Express port service driver is registered with
* pcie_port_service_register(), this function will be called by the driver core
* whenever match is found between the driver and a port service device.
*/
static int pcie_port_probe_service(struct device *dev)
{
struct pcie_device *pciedev;
struct pcie_port_service_driver *driver;
int status;
if (!dev || !dev->driver)
return -ENODEV;
driver = to_service_driver(dev->driver);
if (!driver || !driver->probe)
return -ENODEV;
pciedev = to_pcie_device(dev);
status = driver->probe(pciedev);
if (status)
return status;
dev_printk(KERN_DEBUG, dev, "service driver %s loaded\n", driver->name);
get_device(dev);
return 0;
}
/**
* pcie_port_remove_service - detach driver from given PCI Express port service
* @dev: PCI Express port service device to handle
*
* If PCI Express port service driver is registered with
* pcie_port_service_register(), this function will be called by the driver core
* when device_unregister() is called for the port service device associated
* with the driver.
*/
static int pcie_port_remove_service(struct device *dev)
{
struct pcie_device *pciedev;
struct pcie_port_service_driver *driver;
if (!dev || !dev->driver)
return 0;
pciedev = to_pcie_device(dev);
driver = to_service_driver(dev->driver);
if (driver && driver->remove) {
dev_printk(KERN_DEBUG, dev, "unloading service driver %s\n",
driver->name);
driver->remove(pciedev);
put_device(dev);
}
return 0;
}
/**
* pcie_port_shutdown_service - shut down given PCI Express port service
* @dev: PCI Express port service device to handle
*
* If PCI Express port service driver is registered with
* pcie_port_service_register(), this function will be called by the driver core
* when device_shutdown() is called for the port service device associated
* with the driver.
*/
static void pcie_port_shutdown_service(struct device *dev) {}
/**
* pcie_port_service_register - register PCI Express port service driver
* @new: PCI Express port service driver to register
*/
int pcie_port_service_register(struct pcie_port_service_driver *new)
{
if (pcie_ports_disabled)
return -ENODEV;
new->driver.name = new->name;
new->driver.bus = &pcie_port_bus_type;
new->driver.probe = pcie_port_probe_service;
new->driver.remove = pcie_port_remove_service;
new->driver.shutdown = pcie_port_shutdown_service;
return driver_register(&new->driver);
}
EXPORT_SYMBOL(pcie_port_service_register);
/**
* pcie_port_service_unregister - unregister PCI Express port service driver
* @drv: PCI Express port service driver to unregister
*/
void pcie_port_service_unregister(struct pcie_port_service_driver *drv)
{
driver_unregister(&drv->driver);
}
EXPORT_SYMBOL(pcie_port_service_unregister);