iommu: Enable compile testing for some of drivers

Some of the IOMMU drivers can be compile tested to increase build
coverage.  The OMAP, Rockchip and Exynos drivers use
device.dev_archdata.iommu field which does not exist on all platforms.
The sPAPR TCE and ARM SMMU have also restrictions where they can be
built.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/Kconfig

@@ -273,7 +273,7 @@ config IRQ_REMAP
 # OMAP IOMMU support
 config OMAP_IOMMU
 	bool "OMAP IOMMU Support"
-	depends on ARM && MMU
+	depends on ARM && MMU || (COMPILE_TEST && (ARM || ARM64 || IA64 || SPARC))
 	depends on ARCH_OMAP2PLUS || COMPILE_TEST
 	select IOMMU_API
 	---help---
@@ -291,7 +291,7 @@ config OMAP_IOMMU_DEBUG
 
 config ROCKCHIP_IOMMU
 	bool "Rockchip IOMMU Support"
-	depends on ARM || ARM64
+	depends on ARM || ARM64 || (COMPILE_TEST && (ARM64 || IA64 || SPARC))
 	depends on ARCH_ROCKCHIP || COMPILE_TEST
 	select IOMMU_API
 	select ARM_DMA_USE_IOMMU
@@ -325,7 +325,7 @@ config TEGRA_IOMMU_SMMU
 
 config EXYNOS_IOMMU
 	bool "Exynos IOMMU Support"
-	depends on ARCH_EXYNOS && MMU
+	depends on ARCH_EXYNOS && MMU || (COMPILE_TEST && (ARM || ARM64 || IA64 || SPARC))
 	depends on !CPU_BIG_ENDIAN # revisit driver if we can enable big-endian ptes
 	select IOMMU_API
 	select ARM_DMA_USE_IOMMU
@@ -361,7 +361,7 @@ config IPMMU_VMSA
 
 config SPAPR_TCE_IOMMU
 	bool "sPAPR TCE IOMMU Support"
-	depends on PPC_POWERNV || PPC_PSERIES
+	depends on PPC_POWERNV || PPC_PSERIES || (PPC && COMPILE_TEST)
 	select IOMMU_API
 	help
 	  Enables bits of IOMMU API required by VFIO. The iommu_ops
@@ -370,7 +370,7 @@ config SPAPR_TCE_IOMMU
 # ARM IOMMU support
 config ARM_SMMU
 	tristate "ARM Ltd. System MMU (SMMU) Support"
-	depends on (ARM64 || ARM) && MMU
+	depends on (ARM64 || ARM || (COMPILE_TEST && !GENERIC_ATOMIC64)) && MMU
 	select IOMMU_API
 	select IOMMU_IO_PGTABLE_LPAE
 	select ARM_DMA_USE_IOMMU if ARM
@@ -440,7 +440,7 @@ config S390_IOMMU
 
 config S390_CCW_IOMMU
 	bool "S390 CCW IOMMU Support"
-	depends on S390 && CCW
+	depends on S390 && CCW || COMPILE_TEST
 	select IOMMU_API
 	help
 	  Enables bits of IOMMU API required by VFIO. The iommu_ops
@@ -448,7 +448,7 @@ config S390_CCW_IOMMU
 
 config S390_AP_IOMMU
 	bool "S390 AP IOMMU Support"
-	depends on S390 && ZCRYPT
+	depends on S390 && ZCRYPT || COMPILE_TEST
 	select IOMMU_API
 	help
 	  Enables bits of IOMMU API required by VFIO. The iommu_ops
@@ -456,7 +456,7 @@ config S390_AP_IOMMU
 
 config MTK_IOMMU
 	bool "MTK IOMMU Support"
-	depends on ARM || ARM64
+	depends on ARM || ARM64 || COMPILE_TEST
 	depends on ARCH_MEDIATEK || COMPILE_TEST
 	select ARM_DMA_USE_IOMMU
 	select IOMMU_API