4.14-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 f139492a09f15254fa261245cdbd65555cdf39e3 ]
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 does 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: 76d870ed09ab ("ath10k: enable ASPM") Link: https://lore.kernel.org/r/20230717120503.15276-11-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/ath10k/pci.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c index 07457eb9d4551..27200544162c7 100644 --- a/drivers/net/wireless/ath/ath10k/pci.c +++ b/drivers/net/wireless/ath/ath10k/pci.c @@ -1661,8 +1661,9 @@ static int ath10k_pci_hif_start(struct ath10k *ar) ath10k_pci_irq_enable(ar); ath10k_pci_rx_post(ar);
- pcie_capability_write_word(ar_pci->pdev, PCI_EXP_LNKCTL, - ar_pci->link_ctl); + pcie_capability_clear_and_set_word(ar_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC, + ar_pci->link_ctl & PCI_EXP_LNKCTL_ASPMC);
return 0; } @@ -2516,8 +2517,8 @@ static int ath10k_pci_hif_power_up(struct ath10k *ar)
pcie_capability_read_word(ar_pci->pdev, PCI_EXP_LNKCTL, &ar_pci->link_ctl); - pcie_capability_write_word(ar_pci->pdev, PCI_EXP_LNKCTL, - ar_pci->link_ctl & ~PCI_EXP_LNKCTL_ASPMC); + pcie_capability_clear_word(ar_pci->pdev, PCI_EXP_LNKCTL, + PCI_EXP_LNKCTL_ASPMC);
/* * Bring the target up cleanly.