igc: Enable PCIe PTM

stable inclusion
from stable-v5.10.124
commit ff4443f3fc531f014a9fddaa13d036d82addfbcb
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5L6E7

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ff4443f3fc531f014a9fddaa13d036d82addfbcb

--------------------------------

commit 1b5d73fb 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: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Tested-by: NDvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: NTony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: NMeng Tang <tangmeng@uniontech.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: NWei Li <liwei391@huawei.com>

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>
@@ -5024,6 +5025,10 @@ 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;