6.5-stable review patch. If anyone has any objections, please let me know.
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From: Ilpo Järvinen ilpo.jarvinen@linux.intel.com
[ 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 lukas@wunner.de Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices") Link: https://lore.kernel.org/r/20230717120503.15276-10-ilpo.jarvinen@linux.intel.... Signed-off-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Simon Horman simon.horman@corigine.com Acked-by: Kalle Valo kvalo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 5990a55801f0a..e4f08a066ca10 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)