This is a note to let you know that I've just added the patch titled wifi: ath10k: Use RMW accessors for changing LNKCTL to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-ath10k-use-rmw-accessors-for-changing-lnkctl.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ca07efc8081e5da95f87985a665c753198cf31cd Author: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Date: Mon Jul 17 15:05:02 2023 +0300 wifi: ath10k: Use RMW accessors for changing LNKCTL [ Upstream commit f139492a09f15254fa261245cdbd65555cdf39e3 ] Don't assume that only the driver would be accessing LNKCTL. ASPM policy changes can trigger write to LNKCTL outside of driver's control. Use RMW capability accessors which does proper locking to avoid losing concurrent updates to the register value. On restore, clear the ASPMC field properly. Suggested-by: Lukas Wunner <lukas@xxxxxxxxx> Fixes: 76d870ed09ab ("ath10k: enable ASPM") Link: https://lore.kernel.org/r/20230717120503.15276-11-ilpo.jarvinen@xxxxxxxxxxxxxxx Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx> Acked-by: Kalle Valo <kvalo@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c index c28328c96307b..464dd0246a97d 100644 --- a/drivers/net/wireless/ath/ath10k/pci.c +++ b/drivers/net/wireless/ath/ath10k/pci.c @@ -1960,8 +1960,9 @@ static int ath10k_pci_hif_start(struct ath10k *ar) ath10k_pci_irq_enable(ar); ath10k_pci_rx_post(ar); - pcie_capability_write_word(ar_pci->pdev, PCI_EXP_LNKCTL, - ar_pci->link_ctl); + pcie_capability_clear_and_set_word(ar_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC, + ar_pci->link_ctl & PCI_EXP_LNKCTL_ASPMC); return 0; } @@ -2818,8 +2819,8 @@ static int ath10k_pci_hif_power_up(struct ath10k *ar, pcie_capability_read_word(ar_pci->pdev, PCI_EXP_LNKCTL, &ar_pci->link_ctl); - pcie_capability_write_word(ar_pci->pdev, PCI_EXP_LNKCTL, - ar_pci->link_ctl & ~PCI_EXP_LNKCTL_ASPMC); + pcie_capability_clear_word(ar_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC); /* * Bring the target up cleanly.