From f8dca9806d703def20adaed0ec97a4678f46d72b Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ilpo=20J=C3=A4rvinen?= Date: Mon, 17 Jul 2023 15:05:01 +0300 Subject: [PATCH] wifi: ath12k: Use RMW accessors for changing LNKCTL MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit [ Upstream commit f5a7ac118faf6d4f794975947b3300717eae8fc5 ] 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 do proper locking to avoid losing concurrent updates to the register value. On restore, clear the ASPMC field properly. Suggested-by: Lukas Wunner Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Link: https://lore.kernel.org/r/20230717120503.15276-10-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Reviewed-by: Simon Horman Acked-by: Kalle Valo Signed-off-by: Sasha Levin --- drivers/net/wireless/ath/ath12k/pci.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/ath/ath12k/pci.c b/drivers/net/wireless/ath/ath12k/pci.c index 9f174daf324c9..e1e45eb50f3e3 100644 --- a/drivers/net/wireless/ath/ath12k/pci.c +++ b/drivers/net/wireless/ath/ath12k/pci.c @@ -794,8 +794,8 @@ static void ath12k_pci_aspm_disable(struct ath12k_pci *ab_pci) u16_get_bits(ab_pci->link_ctl, PCI_EXP_LNKCTL_ASPM_L1)); /* disable L0s and L1 */ - pcie_capability_write_word(ab_pci->pdev, PCI_EXP_LNKCTL, - ab_pci->link_ctl & ~PCI_EXP_LNKCTL_ASPMC); + pcie_capability_clear_word(ab_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC); set_bit(ATH12K_PCI_ASPM_RESTORE, &ab_pci->flags); } @@ -803,8 +803,10 @@ static void ath12k_pci_aspm_disable(struct ath12k_pci *ab_pci) static void ath12k_pci_aspm_restore(struct ath12k_pci *ab_pci) { if (test_and_clear_bit(ATH12K_PCI_ASPM_RESTORE, &ab_pci->flags)) - pcie_capability_write_word(ab_pci->pdev, PCI_EXP_LNKCTL, - ab_pci->link_ctl); + pcie_capability_clear_and_set_word(ab_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC, + ab_pci->link_ctl & + PCI_EXP_LNKCTL_ASPMC); } static void ath12k_pci_kill_tasklets(struct ath12k_base *ab) -- 2.47.2