You-Sheng Yang

PCIe ports reserved for VMD use are not visible to BIOS and therefore not
configured to enable PCIe ASPM or LTR values (which BIOS will configure if
they are not set). Lack of this programming results in high power
consumption on laptops as reported in bugzilla. For affected products use
pci_enable_link_state to set the allowed link states for devices on the
root ports. Also set the LTR value to the maximum value needed for the SoC.

This is a workaround for products from Rocket Lake through Alder Lake.
Raptor Lake, the latest product at this time, has already implemented LTR
configuring in BIOS. Future products will move ASPM configuration back to
BIOS as well. As this solution is intended for laptops, support is not
added for hotplug or for devices downstream of a switch on the root port.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=212355
Link: https://bugzilla.kernel.org/show_bug.cgi?id=215063
Link: https://bugzilla.kernel.org/show_bug.cgi?id=213717

Signed-off-by: Michael Bottini <email address hidden>
Signed-off-by: David E. Box <email address hidden>
Reviewed-by: Jon Derrick <email address hidden>
Reviewed-by: Nirmal Patel <email address hidden>
(backported from https://<email address hidden>/)
[vicamo: fix missed entries in vmd_ids]
Signed-off-by: You-Sheng Yang (vicamo) <email address hidden>

c5125fd... by David Box on 2022-11-03

UBUNTU: SAUCE: PCI: vmd: Create feature grouping for client products

BugLink: https://bugs.launchpad.net/somerville/+bug/1996620

Simplify the device ID list by creating a grouping of features shared by
client products.

Suggested-by: Jon Derrick <email address hidden>
Signed-off-by: David E. Box <email address hidden>
(backported from https://<email address hidden>/)
[vicamo: fix missed entries in vmd_ids]
Signed-off-by: You-Sheng Yang (vicamo) <email address hidden>

d0461fd... by David Box on 2022-11-03

UBUNTU: SAUCE: PCI: vmd: Use PCI_VDEVICE in device list

BugLink: https://bugs.launchpad.net/somerville/+bug/1996620

Refactor the PCI ID list to use PCI_VDEVICE.

Signed-off-by: David E. Box <email address hidden>
Reviewed-by: Jon Derrick <email address hidden>
Reviewed-by: Nirmal Patel <email address hidden>
(backported from https://<email address hidden>/)
[vicamo: fix missed entries in vmd_ids]
Signed-off-by: You-Sheng Yang (vicamo) <email address hidden>

51c1a1f... by Michael Bottini <email address hidden> on 2022-11-03

UBUNTU: SAUCE: PCI/ASPM: Add pci_enable_link_state()

BugLink: https://bugs.launchpad.net/somerville/+bug/1996620

Add pci_enable_link_state() to allow devices to change the default BIOS
configured states. Clears the BIOS default settings then sets the new
states and reconfigures the link under the semaphore. Also add
PCIE_LINK_STATE_ALL macro for convenience for callers that want to enable
all link states.

Signed-off-by: Michael Bottini <email address hidden>
Signed-off-by: David E. Box <email address hidden>
Acked-by: Bjorn Helgaas <email address hidden>
(cherry picked from https://<email address hidden>/)
Signed-off-by: You-Sheng Yang (vicamo) <email address hidden>

250bf08... by You-Sheng Yang on 2022-11-16