igc: Enable PCIe PTM

commit 1b5d73fb862414106cf270a1a7300ce8ae77de83 upstream.

Enables PCIe PTM (Precision Time Measurement) support in the igc
driver. Notifies the PCI devices that PCIe PTM should be enabled.

PCIe PTM is similar protocol to PTP (Precision Time Protocol) running
in the PCIe fabric, it allows devices to report time measurements from
their internal clocks and the correlation with the PCIe root clock.

The i225 NIC exposes some registers that expose those time
measurements, those registers will be used, in later patches, to
implement the PTP_SYS_OFFSET_PRECISE ioctl().

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Meng Tang <tangmeng@uniontech.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index fd9257c7059a0c2b3f122ef33a4e38581acd12f1..53e31002ce52a3060edb31d05dcdb9e36c2c8ed0 100644 (file)
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -9,6 +9,7 @@
 #include <linux/udp.h>
 #include <linux/ip.h>
 #include <linux/pm_runtime.h>
+#include <linux/pci.h>
 #include <net/pkt_sched.h>
 
 #include <net/ipv6.h>
@@ -5041,6 +5042,10 @@ static int igc_probe(struct pci_dev *pdev,
 
        pci_enable_pcie_error_reporting(pdev);
 
+       err = pci_enable_ptm(pdev, NULL);
+       if (err < 0)
+               dev_info(&pdev->dev, "PCIe PTM not supported by PCIe bus/controller\n");
+
        pci_set_master(pdev);
 
        err = -ENOMEM;