Re: [PATCH v3 2/4] PCI/ACPI: Move supported and control calculations to separaten functions

[Rafael J. Wysocki]

On Tue, Aug 24, 2021 at 2:21 PM Joerg Roedel <joro@xxxxxxxxxx> wrote:
>
> From: Joerg Roedel <jroedel@xxxxxxx>
>
> Move the calculations of supported and controled _OSC features out of
> negotiate_os_control into separate functions.
>
> Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>

Reviewed-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>

> ---
>  drivers/acpi/pci_root.c | 93 ++++++++++++++++++++++++-----------------
>  1 file changed, 55 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index 0c3030a58219..ed4e6b55e9bc 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -396,6 +396,59 @@ static acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 *mask, u32 r
>         return AE_OK;
>  }
>
> +static u32 calculate_support(void)
> +{
> +       u32 support;
> +
> +       /*
> +        * All supported architectures that use ACPI have support for
> +        * PCI domains, so we indicate this in _OSC support capabilities.
> +        */
> +       support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
> +       support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
> +       if (pci_ext_cfg_avail())
> +               support |= OSC_PCI_EXT_CONFIG_SUPPORT;
> +       if (pcie_aspm_support_enabled())
> +               support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
> +       if (pci_msi_enabled())
> +               support |= OSC_PCI_MSI_SUPPORT;
> +       if (IS_ENABLED(CONFIG_PCIE_EDR))
> +               support |= OSC_PCI_EDR_SUPPORT;
> +
> +       return support;
> +}
> +
> +static u32 calculate_control(void)
> +{
> +       u32 control;
> +
> +       control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
> +               | OSC_PCI_EXPRESS_PME_CONTROL;
> +
> +       if (IS_ENABLED(CONFIG_PCIEASPM))
> +               control |= OSC_PCI_EXPRESS_LTR_CONTROL;
> +
> +       if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
> +               control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
> +
> +       if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
> +               control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
> +
> +       if (pci_aer_available())
> +               control |= OSC_PCI_EXPRESS_AER_CONTROL;
> +
> +       /*
> +        * Per the Downstream Port Containment Related Enhancements ECN to
> +        * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
> +        * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
> +        * and EDR.
> +        */
> +       if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
> +               control |= OSC_PCI_EXPRESS_DPC_CONTROL;
> +
> +       return control;
> +}
> +
>  static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
>                                  bool is_pcie)
>  {
> @@ -416,20 +469,7 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
>                 return;
>         }
>
> -       /*
> -        * All supported architectures that use ACPI have support for
> -        * PCI domains, so we indicate this in _OSC support capabilities.
> -        */
> -       support = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
> -       support |= OSC_PCI_HPX_TYPE_3_SUPPORT;
> -       if (pci_ext_cfg_avail())
> -               support |= OSC_PCI_EXT_CONFIG_SUPPORT;
> -       if (pcie_aspm_support_enabled())
> -               support |= OSC_PCI_ASPM_SUPPORT | OSC_PCI_CLOCK_PM_SUPPORT;
> -       if (pci_msi_enabled())
> -               support |= OSC_PCI_MSI_SUPPORT;
> -       if (IS_ENABLED(CONFIG_PCIE_EDR))
> -               support |= OSC_PCI_EDR_SUPPORT;
> +       support = calculate_support();
>
>         decode_osc_support(root, "OS supports", support);
>         status = acpi_pci_osc_support(root, support);
> @@ -456,31 +496,8 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
>                 return;
>         }
>
> -       control = OSC_PCI_EXPRESS_CAPABILITY_CONTROL
> -               | OSC_PCI_EXPRESS_PME_CONTROL;
> -
> -       if (IS_ENABLED(CONFIG_PCIEASPM))
> -               control |= OSC_PCI_EXPRESS_LTR_CONTROL;
> -
> -       if (IS_ENABLED(CONFIG_HOTPLUG_PCI_PCIE))
> -               control |= OSC_PCI_EXPRESS_NATIVE_HP_CONTROL;
> -
> -       if (IS_ENABLED(CONFIG_HOTPLUG_PCI_SHPC))
> -               control |= OSC_PCI_SHPC_NATIVE_HP_CONTROL;
> -
> -       if (pci_aer_available())
> -               control |= OSC_PCI_EXPRESS_AER_CONTROL;
> -
> -       /*
> -        * Per the Downstream Port Containment Related Enhancements ECN to
> -        * the PCI Firmware Spec, r3.2, sec 4.5.1, table 4-5,
> -        * OSC_PCI_EXPRESS_DPC_CONTROL indicates the OS supports both DPC
> -        * and EDR.
> -        */
> -       if (IS_ENABLED(CONFIG_PCIE_DPC) && IS_ENABLED(CONFIG_PCIE_EDR))
> -               control |= OSC_PCI_EXPRESS_DPC_CONTROL;
> +       requested = control = calculate_control();
>
> -       requested = control;
>         status = acpi_pci_osc_control_set(handle, &control,
>                                           OSC_PCI_EXPRESS_CAPABILITY_CONTROL);
>         if (ACPI_SUCCESS(status)) {
> --
> 2.32.0
>