[PATCH 00/16] PCI: MSI parent domain conversion

Nam Cao namcao at linutronix.de
Thu Jun 26 07:47:50 PDT 2025


The initial implementation of PCI/MSI interrupt domains in the hierarchical
interrupt domain model used a shortcut by providing a global PCI/MSI
domain.

This works because the PCI/MSI[X] hardware is standardized and uniform, but
it violates the basic design principle of hierarchical interrupt domains:
Each hardware block involved in the interrupt delivery chain should have a
separate interrupt domain.

For PCI/MSI[X], the interrupt controller is per PCI device and not a global
made-up entity.

Unsurprisingly, the shortcut turned out to have downsides as it does not
allow dynamic allocation of interrupt vectors after initialization and it
prevents supporting IMS on PCI. For further details, see:

https://lore.kernel.org/lkml/20221111120501.026511281@linutronix.de/

The solution is implementing per device MSI domains, this means the
entities which provide global PCI/MSI domain so far have to implement MSI
parent domain functionality instead.

This series converts the PCI controller drivers to implement MSI parent
domain.

 drivers/pci/Kconfig                           |   1 +
 drivers/pci/controller/Kconfig                |  11 +
 drivers/pci/controller/dwc/Kconfig            |   1 +
 .../pci/controller/dwc/pcie-designware-host.c |  68 ++----
 drivers/pci/controller/dwc/pcie-designware.h  |   1 -
 drivers/pci/controller/mobiveil/Kconfig       |   1 +
 .../controller/mobiveil/pcie-mobiveil-host.c  |  42 ++--
 .../pci/controller/mobiveil/pcie-mobiveil.h   |   1 -
 drivers/pci/controller/pci-aardvark.c         |  59 ++---
 drivers/pci/controller/pci-hyperv.c           |  98 ++++++--
 drivers/pci/controller/pcie-altera-msi.c      |  44 ++--
 drivers/pci/controller/pcie-brcmstb.c         |  44 ++--
 drivers/pci/controller/pcie-iproc-msi.c       |  45 ++--
 drivers/pci/controller/pcie-mediatek-gen3.c   |  67 ++---
 drivers/pci/controller/pcie-mediatek.c        |  46 ++--
 drivers/pci/controller/pcie-rcar-host.c       |  69 ++----
 drivers/pci/controller/pcie-xilinx-dma-pl.c   |  48 ++--
 drivers/pci/controller/pcie-xilinx-nwl.c      |  45 ++--
 drivers/pci/controller/pcie-xilinx.c          |  55 +++--
 drivers/pci/controller/plda/Kconfig           |   1 +
 drivers/pci/controller/plda/pcie-plda-host.c  |  44 ++--
 drivers/pci/controller/plda/pcie-plda.h       |   1 -
 drivers/pci/controller/vmd.c                  | 229 +++++++++---------
 23 files changed, 504 insertions(+), 517 deletions(-)

-- 
2.39.5




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