iommu-helper: move the IOMMU_HELPER config symbol to lib/

This way we have one central definition of it, and user can select it as
needed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>

arch/powerpc/Kconfig

@@ -222,6 +222,7 @@ config PPC
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_VIRT_CPU_ACCOUNTING
 	select HAVE_IRQ_TIME_ACCOUNTING
+	select IOMMU_HELPER			if PPC64
 	select IRQ_DOMAIN
 	select IRQ_FORCED_THREADING
 	select MODULES_USE_ELF_RELA
@@ -477,9 +478,6 @@ config MPROFILE_KERNEL
 	depends on PPC64 && CPU_LITTLE_ENDIAN
 	def_bool !DISABLE_MPROFILE_KERNEL
 
-config IOMMU_HELPER
-	def_bool PPC64
-
 config SWIOTLB
 	bool "SWIOTLB support"
 	default n

arch/s390/Kconfig

@@ -708,7 +708,9 @@ config QDIO
 menuconfig PCI
 	bool "PCI support"
 	select PCI_MSI
+	select IOMMU_HELPER
 	select IOMMU_SUPPORT
+
 	help
 	  Enable PCI support.
 
@@ -732,9 +734,6 @@ config PCI_DOMAINS
 config HAS_IOMEM
 	def_bool PCI
 
-config IOMMU_HELPER
-	def_bool PCI
-
 config NEED_SG_DMA_LENGTH
 	def_bool PCI
 

arch/sparc/Kconfig

@@ -66,6 +66,7 @@ config SPARC64
 	select HAVE_SYSCALL_TRACEPOINTS
 	select HAVE_CONTEXT_TRACKING
 	select HAVE_DEBUG_KMEMLEAK
+	select IOMMU_HELPER
 	select SPARSE_IRQ
 	select RTC_DRV_CMOS
 	select RTC_DRV_BQ4802
@@ -105,10 +106,6 @@ config ARCH_DMA_ADDR_T_64BIT
 	bool
 	default y if ARCH_ATU
 
-config IOMMU_HELPER
-	bool
-	default y if SPARC64
-
 config STACKTRACE_SUPPORT
 	bool
 	default y if SPARC64

arch/x86/Kconfig

@@ -874,6 +874,7 @@ config DMI
 
 config GART_IOMMU
 	bool "Old AMD GART IOMMU support"
+	select IOMMU_HELPER
 	select SWIOTLB
 	depends on X86_64 && PCI && AMD_NB
 	---help---
@@ -895,6 +896,7 @@ config GART_IOMMU
 
 config CALGARY_IOMMU
 	bool "IBM Calgary IOMMU support"
+	select IOMMU_HELPER
 	select SWIOTLB
 	depends on X86_64 && PCI
 	---help---
@@ -932,10 +934,6 @@ config SWIOTLB
 	  with more than 3 GB of memory.
 	  If unsure, say Y.
 
-config IOMMU_HELPER
-	def_bool y
-	depends on CALGARY_IOMMU || GART_IOMMU
-
 config MAXSMP
 	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 	depends on X86_64 && SMP && DEBUG_KERNEL

lib/Kconfig

@@ -429,6 +429,9 @@ config SGL_ALLOC
 	bool
 	default n
 
+config IOMMU_HELPER
+	bool
+
 config DMA_DIRECT_OPS
 	bool
 	depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)