* [PATCH v2 8/9] wifi: ath12k: Use RMW accessors for changing LNKCTL
[not found] <20230517105235.29176-1-ilpo.jarvinen@linux.intel.com>
@ 2023-05-17 10:52 ` Ilpo Järvinen
2023-05-17 11:03 ` Kalle Valo
0 siblings, 1 reply; 2+ messages in thread
From: Ilpo Järvinen @ 2023-05-17 10:52 UTC (permalink / raw)
To: linux-pci, Bjorn Helgaas, Lorenzo Pieralisi, Rob Herring,
Krzysztof Wilczyński, Emmanuel Grumbach, Rafael J . Wysocki,
Heiner Kallweit, Lukas Wunner, Kalle Valo, David S. Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni, Sriram R, P Praneesh,
Ramya Gnanasekar, Karthikeyan Periyasamy,
Vasanthakumar Thiagarajan, ath12k, linux-wireless, netdev,
linux-kernel
Cc: Dean Luick, Andy Shevchenko, Ilpo Järvinen, stable
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: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
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/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 9f174daf324c..e1e45eb50f3e 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)
--
2.30.2
--
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