[PATCH v2 4/7] irqchip: Have CONFIG_IRQ_MSI_IOMMU be selected by irqchips that need it
From: Nicolin Chen <hidden>
Date: 2025-02-20 01:32:46
Also in:
linux-iommu, linux-kselftest, linux-patches, lkml
Subsystem:
iommu subsystem, irq subsystem, irqchip drivers, the rest · Maintainers:
Joerg Roedel, Will Deacon, Thomas Gleixner, Linus Torvalds
From: Jason Gunthorpe <jgg@nvidia.com> Currently, IRQ_MSI_IOMMU is selected if DMA_IOMMU is available to provide an implementation for iommu_dma_prepare/compose_msi_msg(). However, it'll make more sense for irqchips that call prepare/compose to select it, and that will trigger all the additional code and data to be compiled into the kernel. If IRQ_MSI_IOMMU is selected with no IOMMU side implementation, then the prepare/compose() will be NOP stubs. If IRQ_MSI_IOMMU is not selected by an irqchip, then the related code on the iommu side is compiled out. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Nicolin Chen <redacted> --- drivers/iommu/Kconfig | 1 - drivers/irqchip/Kconfig | 4 ++++ kernel/irq/Kconfig | 1 + 3 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index ec1b5e32b972..5124e7431fe3 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig@@ -154,7 +154,6 @@ config IOMMU_DMA select DMA_OPS_HELPERS select IOMMU_API select IOMMU_IOVA - select IRQ_MSI_IOMMU select NEED_SG_DMA_LENGTH select NEED_SG_DMA_FLAGS if SWIOTLB
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index c11b9965c4ad..64658a1c3aa1 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig@@ -28,6 +28,7 @@ config ARM_GIC_V2M select ARM_GIC select IRQ_MSI_LIB select PCI_MSI + select IRQ_MSI_IOMMU config GIC_NON_BANKED bool
@@ -38,12 +39,14 @@ config ARM_GIC_V3 select PARTITION_PERCPU select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP select HAVE_ARM_SMCCC_DISCOVERY + select IRQ_MSI_IOMMU config ARM_GIC_V3_ITS bool select GENERIC_MSI_IRQ select IRQ_MSI_LIB default ARM_GIC_V3 + select IRQ_MSI_IOMMU config ARM_GIC_V3_ITS_FSL_MC bool
@@ -408,6 +411,7 @@ config LS_EXTIRQ config LS_SCFG_MSI def_bool y if SOC_LS1021A || ARCH_LAYERSCAPE + select IRQ_MSI_IOMMU depends on PCI_MSI config PARTITION_PERCPU
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 5432418c0fea..9636aed20401 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig@@ -100,6 +100,7 @@ config GENERIC_MSI_IRQ bool select IRQ_DOMAIN_HIERARCHY +# irqchip drivers should select this if they call iommu_dma_prepare_msi() config IRQ_MSI_IOMMU bool
--
2.43.0