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/20221111120501.026511...@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
