[PATCH v7 0/5] PCI/ASPM: Save/restore L1 PM Substates for suspend/resume

[Bjorn Helgaas]

From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

This is some rework of David's series to preserve ASPM L1 substate
configuration across suspend/resume.

We've had several attempts to make this work:

  (unlabeled): https://lore.kernel.org/r/20240128233212.1139663-1-david.e.box@xxxxxxxxxxxxxxx
  v5: https://lore.kernel.org/r/20231221011250.191599-1-david.e.box@xxxxxxxxxxxxxxx
  v4: https://lore.kernel.org/all/20231002070044.2299644-1-mika.westerberg@xxxxxxxxxxxxxxx/
  v3: https://lore.kernel.org/linux-pci/20230925074636.2893747-1-mika.westerberg@xxxxxxxxxxxxxxx/
  v2: https://lore.kernel.org/linux-pci/20230911073352.3472918-1-mika.westerberg@xxxxxxxxxxxxxxx/
  v1: https://lore.kernel.org/linux-pci/20230627062442.54008-1-mika.westerberg@xxxxxxxxxxxxxxx/

The most recent posting is the unlabeled one mentioned above, and I'm
calling it v6 and this rework v7.

Changes since the unlabeled v6:

  - Rename pci_save_aspm_state() to pci_save_aspm_l1ss_state() (this
    is the reason for opening this again, because Vidya's patch [1]
    had to do some incidental renaming).

  - Rename pcie_restore_aspm_l1ss() to pci_restore_aspm_l1ss_state()
    to match.

  - Move the PCI_EXP_LNKCTL_ASPMC from pci_restore_aspm_state() to
    pci_restore_pcie_state() so both writes are in the same place.

  - Rename pci_aspm_get_l1ss() to pci_configure_aspm_l1ss() and add
    the save_buffer there as well.

  - Split [1/5] into two patches: move pci_configure_ltr() and
    pci_bridge_reconfigure_ltr() to aspm.c, and build aspm.c
    unconditionally.

  - Squash [2/5] and [3/5] since [2/5] didn't add any functionality
    itself so they seem like a single logical change.

[1] https://lore.kernel.org/r/20230125133830.20620-1-vidyas@xxxxxxxxxx

David E. Box (5):
  PCI/ASPM: Move pci_configure_ltr() to aspm.c
  PCI/ASPM: Always build aspm.c
  PCI/ASPM: Move pci_save_ltr_state() to aspm.c
  PCI/ASPM: Save L1 PM Substates Capability for suspend/resume
  PCI/ASPM: Call pci_save_ltr_state() from pci_save_pcie_state()

 drivers/pci/pci.c         |  89 ++++------------
 drivers/pci/pci.h         |  13 ++-
 drivers/pci/pcie/Makefile |   2 +-
 drivers/pci/pcie/aspm.c   | 215 ++++++++++++++++++++++++++++++++++++++
 drivers/pci/probe.c       |  62 +----------
 include/linux/pci.h       |   2 +-
 6 files changed, 252 insertions(+), 131 deletions(-)

-- 
2.34.1