Trying to build kernel for ARC with both options
CONFIG_COMPILE_TEST and CONFIG_IOMMU_IO_PGTABLE_LPAE enabled
(which happened really in "allyesconfig") I'm seeing this:
---------------->8----------------
$ make ARCH=arc
...sic...
CC drivers/iommu/io-pgtable-arm.o
linux/drivers/iommu/io-pgtable-arm.c: In
function ?__arm_lpae_alloc_pages?:
linux/drivers/iommu/io-pgtable-arm.c:221:3:
error: implicit declaration of function ?dma_map_single?
[-Werror=implicit-function-declaration]
dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
^
linux/drivers/iommu/io-pgtable-arm.c:221:42:
error: ?DMA_TO_DEVICE? undeclared (first use in this function)
dma = dma_map_single(dev, pages, size, DMA_TO_DEVICE);
^
---------------->8----------------
and so on.

IOMMU_IO_PGTABLE_LPAE depends on DMA API.
So io-pgtable-arm.c should include linux/dma-mapping.h.

Signed-off-by: Lada Trimasova <redacted>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Cc: Vineet Gupta <redacted>
Cc: Will Deacon <redacted>
Cc: Joerg Roedel <joro@8bytes.org>
---
 drivers/iommu/io-pgtable-arm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 7df9777..0b1aca0 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c

@@ -25,6 +25,7 @@
 #include <linux/sizes.h>
 #include <linux/slab.h>
 #include <linux/types.h>
+#include <linux/dma-mapping.h>
 
 #include <asm/barrier.h>
 

-- 
2.5.0