summaryrefslogtreecommitdiff
path: root/drivers/iommu/Kconfig
diff options
context:
space:
mode:
authorLan Tianyu <Tianyu.Lan@microsoft.com>2019-02-27 17:54:04 +0300
committerJoerg Roedel <jroedel@suse.de>2019-02-28 13:12:16 +0300
commit29217a4746835fef35279abbd12c1a1efe83bfca (patch)
treec5ea0066251ce2605754dd785373bb27126d68dc /drivers/iommu/Kconfig
parent84fdfafab849036b5aefa52824b5cb42e887ef0e (diff)
downloadlinux-29217a4746835fef35279abbd12c1a1efe83bfca.tar.xz
iommu/hyper-v: Add Hyper-V stub IOMMU driver
On the bare metal, enabling X2APIC mode requires interrupt remapping function which helps to deliver irq to cpu with 32-bit APIC ID. Hyper-V doesn't provide interrupt remapping function so far and Hyper-V MSI protocol already supports to deliver interrupt to the CPU whose virtual processor index is more than 255. IO-APIC interrupt still has 8-bit APIC ID limitation. This patch is to add Hyper-V stub IOMMU driver in order to enable X2APIC mode successfully in Hyper-V Linux guest. The driver returns X2APIC interrupt remapping capability when X2APIC mode is available. Otherwise, it creates a Hyper-V irq domain to limit IO-APIC interrupts' affinity and make sure cpus assigned with IO-APIC interrupt have 8-bit APIC ID. Define 24 IO-APIC remapping entries because Hyper-V only expose one single IO-APIC and one IO-APIC has 24 pins according IO-APIC spec( https://pdos.csail.mit.edu/6.828/2016/readings/ia32/ioapic.pdf). Reviewed-by: Michael Kelley <mikelley@microsoft.com> Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/Kconfig')
-rw-r--r--drivers/iommu/Kconfig9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index d9a25715650e..34b066541491 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -435,4 +435,13 @@ config QCOM_IOMMU
help
Support for IOMMU on certain Qualcomm SoCs.
+config HYPERV_IOMMU
+ bool "Hyper-V x2APIC IRQ Handling"
+ depends on HYPERV
+ select IOMMU_API
+ default HYPERV
+ help
+ Stub IOMMU driver to handle IRQs as to allow Hyper-V Linux
+ guests to run with x2APIC mode enabled.
+
endif # IOMMU_SUPPORT