From 046182525db611964da0db113dde9d3a2969085c Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Thu, 2 Jan 2020 08:18:02 +0800 Subject: [PATCH] iommu/vt-d: Add Kconfig option to enable/disable scalable mode This adds Kconfig option INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON to make it easier for distributions to enable or disable the Intel IOMMU scalable mode by default during kernel build. Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel --- drivers/iommu/Kconfig | 12 ++++++++++++ drivers/iommu/intel-iommu.c | 7 ++++++- 2 files changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index 0b9d78a0f3ac..bcd1c9510458 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -248,6 +248,18 @@ config INTEL_IOMMU_FLOPPY_WA workaround will setup a 1:1 mapping for the first 16MiB to make floppy (an ISA device) work. +config INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON + bool "Enable Intel IOMMU scalable mode by default" + depends on INTEL_IOMMU + help + Selecting this option will enable by default the scalable mode if + hardware presents the capability. The scalable mode is defined in + VT-d 3.0. The scalable mode capability could be checked by reading + /sys/devices/virtual/iommu/dmar*/intel-iommu/ecap. If this option + is not selected, scalable mode support could also be enabled by + passing intel_iommu=sm_on to the kernel. If not sure, please use + the default value. + config IRQ_REMAP bool "Support for Interrupt Remapping" depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 42966611a192..26c40134817e 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -355,9 +355,14 @@ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain, int dmar_disabled = 0; #else int dmar_disabled = 1; -#endif /*CONFIG_INTEL_IOMMU_DEFAULT_ON*/ +#endif /* CONFIG_INTEL_IOMMU_DEFAULT_ON */ +#ifdef INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON +int intel_iommu_sm = 1; +#else int intel_iommu_sm; +#endif /* INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON */ + int intel_iommu_enabled = 0; EXPORT_SYMBOL_GPL(intel_iommu_enabled); -- 2.20.1