iommu/io-pgtable-arm: Avoid warning with 32-bit phys_addr_t

It's not entirely unreasonable for io-pgtable-arm to be built for configurations with 32-bit phys_addr_t, where the compiler rightly raises a warning about the 36-bit shift. That particular code path should never actually *run* on those systems, but we still want it to compile cleanly, which is easily done by using an unambiguous u64 as the intermediate type instead.

---

Oops, I managed to totally overlook that phys_addr_t would be configuration-dependent, sorry :(

If this can't sneak in on top of the SMMU pull, I'll resend it as a fix for -rc1. It shouldn't be super-critical.

 drivers/iommu/io-pgtable-arm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index a5be4c92c5c8..47b64d3b833f 100644
@@ -211,7 +211,7 @@ static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
 static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
 				  struct arm_lpae_io_pgtable *data)
 {
-	phys_addr_t paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
+	u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
 
 	if (data->pg_shift < 16)
 		return paddr;

2.16.1.dirty

Applied it, thanks Robin.