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| author | Bjorn Helgaas <bhelgaas@google.com> | 2025-11-10 16:22:26 -0600 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2025-11-12 18:51:27 -0600 |
| commit | 575b98e39d817537afdc6c39d35c1de484a64d42 (patch) | |
| tree | dcf8e441b4d2939e9e9a1e7811e4a1689f881134 | |
| parent | 4495bffd86ba0fdabfaef0c41d12f68ec2a1e05b (diff) | |
| download | linux-575b98e39d817537afdc6c39d35c1de484a64d42.tar.gz | |
PCI/ASPM: Add pcie_aspm_remove_cap() to override advertised link states
Add pcie_aspm_remove_cap(). A quirk can use this to prevent use of ASPM
L0s or L1 link states, even if the device advertised support for them.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Link: https://patch.msgid.link/20251110222929.2140564-3-helgaas@kernel.org
| -rw-r--r-- | drivers/pci/pci.h | 2 | ||||
| -rw-r--r-- | drivers/pci/pcie/aspm.c | 13 |
2 files changed, 15 insertions, 0 deletions
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 4492b809094b57..36f8c0985430a4 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -958,6 +958,7 @@ void pci_save_aspm_l1ss_state(struct pci_dev *dev); void pci_restore_aspm_l1ss_state(struct pci_dev *dev); #ifdef CONFIG_PCIEASPM +void pcie_aspm_remove_cap(struct pci_dev *pdev, u32 lnkcap); void pcie_aspm_init_link_state(struct pci_dev *pdev); void pcie_aspm_exit_link_state(struct pci_dev *pdev); void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked); @@ -965,6 +966,7 @@ void pcie_aspm_powersave_config_link(struct pci_dev *pdev); void pci_configure_ltr(struct pci_dev *pdev); void pci_bridge_reconfigure_ltr(struct pci_dev *pdev); #else +static inline void pcie_aspm_remove_cap(struct pci_dev *pdev, u32 lnkcap) { } static inline void pcie_aspm_init_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_exit_link_state(struct pci_dev *pdev) { } static inline void pcie_aspm_pm_state_change(struct pci_dev *pdev, bool locked) { } diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 15d50c08907037..f61d9889750370 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -1542,6 +1542,19 @@ int pci_enable_link_state_locked(struct pci_dev *pdev, int state) } EXPORT_SYMBOL(pci_enable_link_state_locked); +void pcie_aspm_remove_cap(struct pci_dev *pdev, u32 lnkcap) +{ + if (lnkcap & PCI_EXP_LNKCAP_ASPM_L0S) + pdev->aspm_l0s_support = 0; + if (lnkcap & PCI_EXP_LNKCAP_ASPM_L1) + pdev->aspm_l1_support = 0; + + pci_info(pdev, "ASPM: Link Capabilities%s%s treated as unsupported to avoid device defect\n", + lnkcap & PCI_EXP_LNKCAP_ASPM_L0S ? " L0s" : "", + lnkcap & PCI_EXP_LNKCAP_ASPM_L1 ? " L1" : ""); + +} + static int pcie_aspm_set_policy(const char *val, const struct kernel_param *kp) { |