Commit 1468c1f9 authored by ValdikSS's avatar ValdikSS Committed by Jakub Kicinski
Browse files

igc: fix disabling L1.2 PCI-E link substate on I226 on init 

Device ID comparison in igc_is_device_id_i226 is performed before
the ID is set, resulting in always failing check on init.

Before the patch:
* L1.2 is not disabled on init
* L1.2 is properly disabled after suspend-resume cycle

With the patch:
* L1.2 is properly disabled both on init and after suspend-resume

How to test:
Connect to the 1G link with 300+ mbit/s Internet speed, and run
the download speed test, such as:

    curl -o /dev/null http://speedtest.selectel.ru/1GB

Without L1.2 disabled, the speed would be no more than ~200 mbit/s.
With L1.2 disabled, the speed would reach 1 gbit/s.
Note: it's required that the latency between your host and the remote
be around 3-5 ms, the test inside LAN (<1 ms latency) won't trigger the
issue.

Link: https://lore.kernel.org/intel-wired-lan/15248b4f-3271-42dd-8e35-02bfc92b25e1@intel.com


Fixes: 0325143b ("igc: disable L1.2 PCI-E link substate to avoid performance issue")
Signed-off-by: default avatarValdikSS <iam@valdikss.org.ru>
Reviewed-by: default avatarVitaly Lifshits <vitaly.lifshits@intel.com>
Reviewed-by: default avatarPaul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: default avatarTony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20250819222000.3504873-6-anthony.l.nguyen@intel.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f3d9f7fa

drivers/net/ethernet/intel/igc/igc_main.c

+7 −7
Original line number Diff line number Diff line
@@ -7149,6 +7149,13 @@ static int igc_probe(struct pci_dev *pdev, 
	adapter->port_num = hw->bus.func;

	adapter->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);



	/* PCI config space info */

	hw->vendor_id = pdev->vendor;

	hw->device_id = pdev->device;

	hw->revision_id = pdev->revision;

	hw->subsystem_vendor_id = pdev->subsystem_vendor;

	hw->subsystem_device_id = pdev->subsystem_device;



	/* Disable ASPM L1.2 on I226 devices to avoid packet loss */

	if (igc_is_device_id_i226(hw))

		pci_disable_link_state(pdev, PCIE_LINK_STATE_L1_2);
@@ -7175,13 +7182,6 @@ static int igc_probe(struct pci_dev *pdev, 
	netdev->mem_start = pci_resource_start(pdev, 0);

	netdev->mem_end = pci_resource_end(pdev, 0);



	/* PCI config space info */

	hw->vendor_id = pdev->vendor;

	hw->device_id = pdev->device;

	hw->revision_id = pdev->revision;

	hw->subsystem_vendor_id = pdev->subsystem_vendor;

	hw->subsystem_device_id = pdev->subsystem_device;



	/* Copy the default MAC and PHY function pointers */

	memcpy(&hw->mac.ops, ei->mac_ops, sizeof(hw->mac.ops));

	memcpy(&hw->phy.ops, ei->phy_ops, sizeof(hw->phy.ops));