[PATCH v2 0/4] PCI/ASPM: Allow quirks to avoid L0s and L1

[Shawn Lin]

在 2025/11/11 星期二 6:22, Bjorn Helgaas 写道:
> From: Bjorn Helgaas <bhelgaas at google.com>
> 
> We enabled ASPM too aggressively in v6.18-rc1.  f3ac2ff14834 ("PCI/ASPM:
> Enable all ClockPM and ASPM states for devicetree platforms") enabled ASPM
> L0s, L1, and (if advertised) L1 PM Substates.
> 
> df5192d9bb0e ("PCI/ASPM: Enable only L0s and L1 for devicetree platforms")
> (v6.18-rc3) backed off and omitted Clock PM and L1 Substates because we
> don't have good infrastructure to discover CLKREQ# support, and L1
> Substates may require device-specific configuration.
> 
> L0s and L1 are generically discoverable and should not require
> device-specific support, but some devices advertise them even though they
> don't work correctly.  This series is a way to add quirks avoid L0s and L1
> in this case.
> 

Tested-by: Shawn Lin <shawn.lin at rock-chips.com>

> 
> Bjorn Helgaas (4):
>    PCI/ASPM: Cache L0s/L1 Supported so advertised link states can be
>      overridden
>    PCI/ASPM: Add pcie_aspm_remove_cap() to override advertised link
>      states
>    PCI/ASPM: Convert quirks to override advertised link states
>    PCI/ASPM: Avoid L0s and L1 on Freescale Root Ports
> 
>   drivers/pci/pci.h       |  2 ++
>   drivers/pci/pcie/aspm.c | 25 +++++++++++++++++--------
>   drivers/pci/probe.c     |  7 +++++++
>   drivers/pci/quirks.c    | 38 +++++++++++++++++++-------------------
>   include/linux/pci.h     |  2 ++
>   5 files changed, 47 insertions(+), 27 deletions(-)
>