On 2/24/23 7:46 PM, Kai-Heng Feng wrote:
> Introduce a new helper, pcie_aspm_capable(), to report ASPM capability.
>
> The user will be introduced by next patch.
Instead of just saying next patch, just say which driver or use case is
going to use it.
>
> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Suggested-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---
> v9:
> v8:
> - No change.
>
> v7:
> - Change subject.
>
> v6:
> - No change.
>
> v5:
> - No change.
>
> v4:
> - Report aspm_capable instead.
>
> v3:
> - This is a new patch
>
> drivers/pci/pcie/aspm.c | 11 +++++++++++
> include/linux/pci.h | 2 ++
> 2 files changed, 13 insertions(+)
>
> diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
> index 692d6953f0970..d96bf0a362aa2 100644
> --- a/drivers/pci/pcie/aspm.c
> +++ b/drivers/pci/pcie/aspm.c
> @@ -1199,6 +1199,17 @@ bool pcie_aspm_enabled(struct pci_dev *pdev)
> }
> EXPORT_SYMBOL_GPL(pcie_aspm_enabled);
>
> +bool pcie_aspm_capable(struct pci_dev *pdev)
> +{
> + struct pcie_link_state *link = pcie_aspm_get_link(pdev);
> +
> + if (!link)
> + return false;
> +
> + return link->aspm_capable;
> +}
> +EXPORT_SYMBOL_GPL(pcie_aspm_capable);
> +
> static ssize_t aspm_attr_show_common(struct device *dev,
> struct device_attribute *attr,
> char *buf, u8 state)
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index adffd65e84b4e..fd56872883e14 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -1692,6 +1692,7 @@ int pci_disable_link_state_locked(struct pci_dev *pdev, int state);
> void pcie_no_aspm(void);
> bool pcie_aspm_support_enabled(void);
> bool pcie_aspm_enabled(struct pci_dev *pdev);
> +bool pcie_aspm_capable(struct pci_dev *pdev);
> #else
> static inline int pci_disable_link_state(struct pci_dev *pdev, int state)
> { return 0; }
> @@ -1700,6 +1701,7 @@ static inline int pci_disable_link_state_locked(struct pci_dev *pdev, int state)
> static inline void pcie_no_aspm(void) { }
> static inline bool pcie_aspm_support_enabled(void) { return false; }
> static inline bool pcie_aspm_enabled(struct pci_dev *pdev) { return false; }
> +static inline bool pcie_aspm_capable(struct pci_dev *pdev) { return false; }
> #endif
>
> #ifdef CONFIG_PCIEAER
--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer
