Re: [PATCH v2 2/7] PCI: ACPI: PM: Do not use pci_platform_pm_ops for ACPI

From: Rafael J. Wysocki
Date: Thu Sep 23 2021 - 09:35:22 EST


On Thu, Sep 23, 2021 at 3:26 PM Ferry Toth <fntoth@xxxxxxxxx> wrote:
>
> Hi,
>
> Op 23-09-2021 om 13:30 schreef Rafael J. Wysocki:
>
> On Wed, Sep 22, 2021 at 11:31 PM Ferry Toth <fntoth@xxxxxxxxx> wrote:
>
> Hi,
> Op 20-09-2021 om 21:17 schreef Rafael J. Wysocki:
>
> From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Using struct pci_platform_pm_ops for ACPI adds unnecessary
> indirection to the interactions between the PCI core and ACPI PM,
> which is also subject to retpolines.
>
> Moreover, it is not particularly clear from the current code that,
> as far as PCI PM is concerned, "platform" really means just ACPI
> except for the special casess when Intel MID PCI PM is used or when
> ACPI support is disabled (through the kernel config or command line,
> or because there are no usable ACPI tables on the system).
>
> To address the above, rework the PCI PM code to invoke ACPI PM
> functions directly as needed and drop the acpi_pci_platform_pm
> object that is not necessary any more.
>
> Accordingly, update some of the ACPI PM functions in question to do
> extra checks in case the ACPI support is disabled (which previously
> was taken care of by avoiding to set the pci_platform_ops pointer
> in those cases).
>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> ---
>
> v1 -> v2:
> * Rebase on top of the new [1/7] and move dropping struct
> pci_platform_pm_ops to a separate patch.
>
> I wanted to test this series on 5.15-rc2 but this patch 2/7 doesn't
> apply (after 1/7 applied). Should I apply this on another tree?
>
> This is on top of
> https://patchwork.kernel.org/project/linux-acpi/patch/2793105.e9J7NaK4W3@kreacher/
> which is not yet in any tree.
>
> Sorry for the confusion.
>
> No problem at all. If I can I will try to report back tonight. Else, will be delayed 2 due to a short break.

Thank you!