iommu/arm-smmu: ioremap smmu mmio region before implementation init

ioremap smmu mmio region before calling into implementation init.
This is necessary to allow mapped address available during vendor
specific implementation init.
Signed-off-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Pritesh Raithatha <praithatha@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Link: https://lore.kernel.org/r/20200718193457.30046-3-vdumpa@nvidia.comSigned-off-by: Will Deacon <will@kernel.org>

drivers/iommu/arm-smmu.c

@@ -2123,10 +2123,6 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
-	smmu = arm_smmu_impl_init(smmu);
-	if (IS_ERR(smmu))
-		return PTR_ERR(smmu);
-
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	ioaddr = res->start;
 	smmu->base = devm_ioremap_resource(dev, res);
@@ -2138,6 +2134,10 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	 */
 	smmu->numpage = resource_size(res);
 
+	smmu = arm_smmu_impl_init(smmu);
+	if (IS_ERR(smmu))
+		return PTR_ERR(smmu);
+
 	num_irqs = 0;
 	while ((res = platform_get_resource(pdev, IORESOURCE_IRQ, num_irqs))) {
 		num_irqs++;