void pci_ptm_init(struct pci_dev *dev)
{
int pos;
u32 cap, ctrl;
u8 local_clock;
struct pci_dev *ups;
if (!pci_is_pcie(dev))
return;
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM);
if (!pos)
return;
/*
* Enable PTM only on interior devices (root ports, switch ports,
* etc.) on the assumption that it causes no link traffic until an
* endpoint enables it.
*/
if ((pci_pcie_type(dev) == PCI_EXP_TYPE_ENDPOINT ||
pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END))
return;
pci_read_config_dword(dev, pos + PCI_PTM_CAP, &cap);
local_clock = (cap & PCI_PTM_GRANULARITY_MASK) >> 8;
/*
* There's no point in enabling PTM unless it's enabled in the
* upstream device or this device can be a PTM Root itself. Per
* the spec recommendation (PCIe r3.1, sec 7.32.3), select the
* furthest upstream Time Source as the PTM Root.
*/
ups = pci_upstream_bridge(dev);
if (ups && ups->ptm_enabled) {
ctrl = PCI_PTM_CTRL_ENABLE;
if (ups->ptm_granularity == 0)
dev->ptm_granularity = 0;
else if (ups->ptm_granularity > local_clock)
dev->ptm_granularity = ups->ptm_granularity;
} else {
if (cap & PCI_PTM_CAP_ROOT) {
ctrl = PCI_PTM_CTRL_ENABLE | PCI_PTM_CTRL_ROOT;
dev->ptm_root = 1;
dev->ptm_granularity = local_clock;
} else
return;
}
ctrl |= dev->ptm_granularity << 8;
pci_write_config_dword(dev, pos + PCI_PTM_CTRL, ctrl);
dev->ptm_enabled = 1;
pci_ptm_info(dev);
}
int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val)
{
int ret;
*val = 0;
if (pos & 3)
return -EINVAL;
if (pcie_capability_reg_implemented(dev, pos)) {
ret = pci_read_config_dword(dev, pci_pcie_cap(dev) + pos, val);
/*
* Reset *val to 0 if pci_read_config_dword() fails, it may
* have been written as 0xFFFFFFFF if hardware error happens
* during pci_read_config_dword().
*/
if (ret)
*val = 0;
return ret;
}
if (pci_is_pcie(dev) && pos == PCI_EXP_SLTCTL &&
pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM) {
*val = PCI_EXP_SLTSTA_PDS;
}
return 0;
}
int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val)
{
int ret;
*val = 0;
if (pos & 1)
return -EINVAL;
if (pcie_capability_reg_implemented(dev, pos)) {
ret = pci_read_config_word(dev, pci_pcie_cap(dev) + pos, val);
/*
* Reset *val to 0 if pci_read_config_word() fails, it may
* have been written as 0xFFFF if hardware error happens
* during pci_read_config_word().
*/
if (ret)
*val = 0;
return ret;
}
/*
* For Functions that do not implement the Slot Capabilities,
* Slot Status, and Slot Control registers, these spaces must
* be hardwired to 0b, with the exception of the Presence Detect
* State bit in the Slot Status register of Downstream Ports,
* which must be hardwired to 1b. (PCIe Base Spec 3.0, sec 7.8)
*/
if (pci_is_pcie(dev) && pos == PCI_EXP_SLTSTA &&
pci_pcie_type(dev) == PCI_EXP_TYPE_DOWNSTREAM) {
*val = PCI_EXP_SLTSTA_PDS;
}
return 0;
}
int pci_cleanup_aer_error_status_regs(struct pci_dev *dev)
{
int pos;
u32 status;
int port_type;
if (!pci_is_pcie(dev))
return -ENODEV;
pos = dev->aer_cap;
if (!pos)
return -EIO;
port_type = pci_pcie_type(dev);
if (port_type == PCI_EXP_TYPE_ROOT_PORT) {
pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, &status);
pci_write_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, status);
}
pci_read_config_dword(dev, pos + PCI_ERR_COR_STATUS, &status);
pci_write_config_dword(dev, pos + PCI_ERR_COR_STATUS, status);
pci_read_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, &status);
pci_write_config_dword(dev, pos + PCI_ERR_UNCOR_STATUS, status);
return 0;
}
static inline bool pcie_cap_has_rtctl(const struct pci_dev *dev)
{
int type = pci_pcie_type(dev);
return type == PCI_EXP_TYPE_ROOT_PORT ||
type == PCI_EXP_TYPE_RC_EC;
}
static bool pcie_downstream_port(const struct pci_dev *dev)
{
int type = pci_pcie_type(dev);
return type == PCI_EXP_TYPE_ROOT_PORT ||
type == PCI_EXP_TYPE_DOWNSTREAM;
}
int pci_enable_ptm(struct pci_dev *dev, u8 *granularity)
{
int pos;
u32 cap, ctrl;
struct pci_dev *ups;
if (!pci_is_pcie(dev))
return -EINVAL;
pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PTM);
if (!pos)
return -EINVAL;
pci_read_config_dword(dev, pos + PCI_PTM_CAP, &cap);
if (!(cap & PCI_PTM_CAP_REQ))
return -EINVAL;
/*
* For a PCIe Endpoint, PTM is only useful if the endpoint can
* issue PTM requests to upstream devices that have PTM enabled.
*
* For Root Complex Integrated Endpoints, there is no upstream
* device, so there must be some implementation-specific way to
* associate the endpoint with a time source.
*/
if (pci_pcie_type(dev) == PCI_EXP_TYPE_ENDPOINT) {
ups = pci_upstream_bridge(dev);
if (!ups || !ups->ptm_enabled)
return -EINVAL;
dev->ptm_granularity = ups->ptm_granularity;
} else if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) {
dev->ptm_granularity = 0;
} else
return -EINVAL;
ctrl = PCI_PTM_CTRL_ENABLE;
ctrl |= dev->ptm_granularity << 8;
pci_write_config_dword(dev, pos + PCI_PTM_CTRL, ctrl);
dev->ptm_enabled = 1;
pci_ptm_info(dev);
if (granularity)
*granularity = dev->ptm_granularity;
return 0;
}
static inline bool pcie_cap_has_sltctl(struct pci_dev *dev)
{
int type = pci_pcie_type(dev);
return pcie_cap_version(dev) > 1 ||
type == PCI_EXP_TYPE_ROOT_PORT ||
(type == PCI_EXP_TYPE_DOWNSTREAM &&
pcie_flags_reg(dev) & PCI_EXP_FLAGS_SLOT);
}
static inline bool pcie_cap_has_lnkctl(struct pci_dev *dev)
{
int type = pci_pcie_type(dev);
return pcie_cap_version(dev) > 1 ||
type == PCI_EXP_TYPE_ROOT_PORT ||
type == PCI_EXP_TYPE_ENDPOINT ||
type == PCI_EXP_TYPE_LEG_END;
}
bool pcie_cap_has_lnkctl(const struct pci_dev *dev)
{
int type = pci_pcie_type(dev);
return type == PCI_EXP_TYPE_ENDPOINT ||
type == PCI_EXP_TYPE_LEG_END ||
type == PCI_EXP_TYPE_ROOT_PORT ||
type == PCI_EXP_TYPE_UPSTREAM ||
type == PCI_EXP_TYPE_DOWNSTREAM ||
type == PCI_EXP_TYPE_PCI_BRIDGE ||
type == PCI_EXP_TYPE_PCIE_BRIDGE;
}
static int pcie_port_resume_noirq(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
/*
* Some BIOSes forget to clear Root PME Status bits after system wakeup
* which breaks ACPI-based runtime wakeup on PCI Express, so clear those
* bits now just in case (shouldn't hurt).
*/
if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ROOT_PORT)
pcie_clear_root_pme_status(pdev);
return 0;
}
static pci_ers_result_t reset_link(struct pci_dev *dev)
{
struct pci_dev *udev;
pci_ers_result_t status;
struct pcie_port_service_driver *driver;
if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
/* Reset this port for all subordinates */
udev = dev;
} else {
/* Reset the upstream component (likely downstream port) */
udev = dev->bus->self;
}
/* Use the aer driver of the component firstly */
driver = find_aer_service(udev);
if (driver && driver->reset_link) {
status = driver->reset_link(udev);
} else if (pci_pcie_type(udev) == PCI_EXP_TYPE_DOWNSTREAM ||
pci_pcie_type(udev) == PCI_EXP_TYPE_ROOT_PORT) {
status = default_reset_link(udev);
} else {
dev_printk(KERN_DEBUG, &dev->dev,
"no link-reset support at upstream device %s\n",
pci_name(udev));
return PCI_ERS_RESULT_DISCONNECT;
}
if (status != PCI_ERS_RESULT_RECOVERED) {
dev_printk(KERN_DEBUG, &dev->dev,
"link reset at upstream device %s failed\n",
pci_name(udev));
return PCI_ERS_RESULT_DISCONNECT;
}
return status;
}
/*
* pcie_portdrv_probe - Probe PCI-Express port devices
* @dev: PCI-Express port device being probed
*
* If detected invokes the pcie_port_device_register() method for
* this port device.
*
*/
static int pcie_portdrv_probe(struct pci_dev *dev,
const struct pci_device_id *id)
{
int status;
if (!pci_is_pcie(dev) ||
((pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) &&
(pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM) &&
(pci_pcie_type(dev) != PCI_EXP_TYPE_DOWNSTREAM)))
return -ENODEV;
status = pcie_port_device_register(dev);
if (status)
return status;
pci_save_state(dev);
/*
* D3cold may not work properly on some PCIe port, so disable
* it by default.
*/
dev->d3cold_allowed = false;
return 0;
}
static int pcie_port_bus_match(struct device *dev, struct device_driver *drv)
{
struct pcie_device *pciedev;
struct pcie_port_service_driver *driver;
if (drv->bus != &pcie_port_bus_type || dev->bus != &pcie_port_bus_type)
return 0;
pciedev = to_pcie_device(dev);
driver = to_service_driver(drv);
if (driver->service != pciedev->service)
return 0;
if ((driver->port_type != PCIE_ANY_PORT) &&
(driver->port_type != pci_pcie_type(pciedev->port)))
return 0;
return 1;
}
