This RFC adds support for MSI for platform devices. MSI block is added as an ext irq along with the existing wired interrupt implementation. The patchset exports two caps for MSI and related data to configure MSI source device. Changes from: ------------- v3 to v4: 1) Removed the 'cap' for exporting MSI info to userspace and restored into vedor specific module. 2) Enable GENERIC_MSI_IRQ_DOMAIN in Kconfig. 3) Removed the vendor specific, Broadcom, 'msi' module and integrated the MSI relates ops into the 'reset' module for MSI support. v2 to v3: 1) Restored the vendor specific module to get max number of MSIs supported and .count value initialized. 2) Comments from Eric addressed. v1 to v2: 1) IRQ allocation has been implemented as below: ---------------------------- |IRQ-0|IRQ-1|....|IRQ-n|MSI| ---------------------------- MSI block has msi contexts and its implemneted as ext irq. 2) Removed vendor specific module for msi handling so previously patch2 and patch3 are not required. 3) MSI related data is exported to userspace using 'caps'. Please note VFIO_IRQ_INFO_CAP_TYPE in include/uapi/linux/vfio.h implementation is taken from the Eric`s patch https://patchwork.kernel.org/project/kvm/patch/20201116110030.32335-8-eric.auger@redhat.com/ v0 to v1: i) Removed MSI device flag VFIO_DEVICE_FLAGS_MSI. ii) Add MSI(s) at the end of the irq list of platform IRQs. MSI(s) with first entry of MSI block has count and flag information. IRQ list: Allocation for IRQs + MSIs are allocated as below Example: if there are 'n' IRQs and 'k' MSIs ------------------------------------------------------- |IRQ-0|IRQ-1|....|IRQ-n|MSI-0|MSI-1|MSI-2|......|MSI-k| ------------------------------------------------------- MSI-0 will have count=k set and flags set accordingly. Vikas Gupta (3): vfio/platform: add support for msi vfio/platform: change cleanup order vfio: platform: reset: add msi support drivers/vfio/platform/Kconfig | 1 + .../platform/reset/vfio_platform_bcmflexrm.c | 72 ++++- drivers/vfio/platform/vfio_platform_common.c | 97 +++++-- drivers/vfio/platform/vfio_platform_irq.c | 253 ++++++++++++++++-- drivers/vfio/platform/vfio_platform_private.h | 29 ++ include/uapi/linux/vfio.h | 24 ++ 6 files changed, 444 insertions(+), 32 deletions(-) -- 2.17.1