Microconference-ACPI/PM, PCI subsystems

The Linux Plumbers 2013 Microconference-ACPI/PM (Advanced Configuration and Power Interface/Power Management), PCI (Peripheral Component Interconnect) subsystems track will focus on current and future development of these areas. There is significant overlap between ACPI/PM and PCI so it makes sense to have an event covering them both.

Since this is “Plumbers” were particularly interested in topics concerning userspace (i.e. userspace interactions, drivers, …) but be warned that the majority of content discussed may have more focus on these subsystem's internals - it will depend on the responses we receive from the community. As always, this will be a great opportunity for developers to meet and collaborate.

Possible Topics (Not complete, nor final; Ideas are welcome):

• Host bridge hot-plug (I/O APIC, …)
• ACPI-based hot-plug of things in general (including PCI host bridges)
• PCI hot-plug and ACPI (acpiphp vs pciehp and dependency on bridges)
• Device hot-plug (IRQ fixups, …)
• Interactions between PCI PM and hot-plug (for PCIe ports in particular)
• PCI on ARM (emulated p2p bridges; shared host bridge drivers in ./drivers/pci/host/*; …)
• Max Payload Size [MPS, MTRR]
• New PCI capabilities (Gen 3 and beyond)
• PCI secondary bus resets (How to avoid surprise hot-plug and/or how to re-architect the device reset interface)
• pci_is_pcie() (Not just for PCIe capabilities? - How to handle non-compliant PCIe devices that don't expose a capability)
• I/O port pci-sysfs resource files (Fix or remove?)
• Thunderbolt support in Linux PCI core
• PM QoS for PCI devices (resume latency limit and possibly LTR)
• Resource management using ACPI (_CRS and friends)
• Unification opportunities (domain support, NUMA node, …)
• Virtualization (device assignment for vguests, DMA remapping, …)
• Virt: device reset and hot-plug interaction
• SR-IOV (VFs on virtual buses)
• SR-IOV: enable VFs for vguests independent of loading the PF driver
• Integration of PM frameworks (cpuidle, cpufreq, runtime PM, system suspend)
• User settings for PM policy (how to pass policy information, e.g. power vs performance, to kernel subsystems)
• CONFIG_PM consolidation (what should depend on it, are CONFIG_PM_* necessary)

The structure will be similar to what occurred at last year's kernel summit in which in-progress and future projects were brought up prompting discussions from all attendees concentrating on current problems and possible directions towards solutions (i.e. focus on existing and possible future issues related to unfinished, sticky, topics as opposed to presenting about problems that have already been solved).

We will likely group presentations into ACPI/PM, PCI, and VIRT to accommodate attendees with specific focus. A list of possible presenters in these areas (feel free to volunteer yourself, or others) is:

ACPI/PM: Len Brown, Rafael J Wysocki+
PCI: Bjorn Helgaas+, Ben Herrenschmidt, Jiang Liu, Yinghai Lu, Myron Stowe+, Yijing Wang
SR-IOV: Don Dutile, Joerg Roedel, Alex Williamson+, David Woodhouse

The schedule of the 2013 Microconference-ACPI/PM, PCI subsystems Plumbers Micro Conference is as follows. Note presentation slides can be found on the Plumbers page by following the links to the abstracts:

• Session 1 - Presenter 1
• Session 2 - Presenter 2
• etc…

This is a good place to record notes from your session. All too often, if notes were not written down, the session might as well not have happened.

Proposal added by Len Brown len.brown@intel.com, Bjorn Helgaas bhelgaas@google.com, Myron Stowe myron.stowe@gmail.com and Rafael J. Wysocki rjw@sisk.pl