6.4-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 6c1b6bdb34aaf8f94f65a9cae1d63490320c11bc ]
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: e9603f4bdcc0 ("ath11k: pci: disable ASPM L0sLs before downloading firmware") Link: https://lore.kernel.org/r/20230717120503.15276-9-ilpo.jarvinen@linux.intel.c... 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/ath11k/pci.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c index 7b33731a50ee7..6ba4cef6b1c7d 100644 --- a/drivers/net/wireless/ath/ath11k/pci.c +++ b/drivers/net/wireless/ath/ath11k/pci.c @@ -581,8 +581,8 @@ static void ath11k_pci_aspm_disable(struct ath11k_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(ATH11K_PCI_ASPM_RESTORE, &ab_pci->flags); } @@ -590,8 +590,10 @@ static void ath11k_pci_aspm_disable(struct ath11k_pci *ab_pci) static void ath11k_pci_aspm_restore(struct ath11k_pci *ab_pci) { if (test_and_clear_bit(ATH11K_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 int ath11k_pci_power_up(struct ath11k_base *ab)