diff mbox series

[v2,7/9] wifi: ath11k: Use RMW accessors for changing LNKCTL

Message ID 20230517105235.29176-8-ilpo.jarvinen@linux.intel.com (mailing list archive)
State Awaiting Upstream
Delegated to: Netdev Maintainers
Headers show
Series None | expand

Commit Message

Ilpo Järvinen May 17, 2023, 10:52 a.m. UTC
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.

Fixes: e9603f4bdcc0 ("ath11k: pci: disable ASPM L0sLs before downloading firmware")
Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Cc: stable@vger.kernel.org
---
 drivers/net/wireless/ath/ath11k/pci.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

Comments

Kalle Valo May 17, 2023, 11:04 a.m. UTC | #1
Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> writes:

> 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.
>
> Fixes: e9603f4bdcc0 ("ath11k: pci: disable ASPM L0sLs before downloading firmware")
> Suggested-by: Lukas Wunner <lukas@wunner.de>
> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Cc: stable@vger.kernel.org

Acked-by: Kalle Valo <kvalo@kernel.org>
diff mbox series

Patch

diff --git a/drivers/net/wireless/ath/ath11k/pci.c b/drivers/net/wireless/ath/ath11k/pci.c
index 7b33731a50ee..6ba4cef6b1c7 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)