iommu/exynos: Init from dt-specific callback instead of initcall

This patch introduces IOMMU_OF_DECLARE-based initialization to the
driver, which replaces subsys_initcall-based procedure.
exynos_iommu_of_setup ensures that each sysmmu controller is probed
before its master device.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/exynos-iommu.c

@@ -13,16 +13,21 @@
 #endif
 
 #include <linux/clk.h>
+#include <linux/dma-mapping.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/iommu.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
+#include <linux/of.h>
+#include <linux/of_iommu.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
 
 #include <asm/cacheflush.h>
+#include <asm/dma-iommu.h>
 #include <asm/pgtable.h>
 
 typedef u32 sysmmu_iova_t;
@@ -1141,7 +1146,7 @@ static void exynos_iommu_remove_device(struct device *dev)
 	iommu_group_remove_device(dev);
 }
 
-static const struct iommu_ops exynos_iommu_ops = {
+static struct iommu_ops exynos_iommu_ops = {
 	.domain_alloc = exynos_iommu_domain_alloc,
 	.domain_free = exynos_iommu_domain_free,
 	.attach_dev = exynos_iommu_attach_device,
@@ -1155,17 +1160,12 @@ static const struct iommu_ops exynos_iommu_ops = {
 	.pgsize_bitmap = SECT_SIZE | LPAGE_SIZE | SPAGE_SIZE,
 };
 
+static bool init_done;
+
 static int __init exynos_iommu_init(void)
 {
-	struct device_node *np;
 	int ret;
 
-	np = of_find_matching_node(NULL, sysmmu_of_match);
-	if (!np)
-		return 0;
-
-	of_node_put(np);
-
 	lv2table_kmem_cache = kmem_cache_create("exynos-iommu-lv2table",
 				LV2TABLE_SIZE, LV2TABLE_SIZE, 0, NULL);
 	if (!lv2table_kmem_cache) {
@@ -1194,6 +1194,8 @@ static int __init exynos_iommu_init(void)
 		goto err_set_iommu;
 	}
 
+	init_done = true;
+
 	return 0;
 err_set_iommu:
 	kmem_cache_free(lv2table_kmem_cache, zero_lv2_table);
@@ -1203,4 +1205,21 @@ err_reg_driver:
 	kmem_cache_destroy(lv2table_kmem_cache);
 	return ret;
 }
-subsys_initcall(exynos_iommu_init);
+
+static int __init exynos_iommu_of_setup(struct device_node *np)
+{
+	struct platform_device *pdev;
+
+	if (!init_done)
+		exynos_iommu_init();
+
+	pdev = of_platform_device_create(np, NULL, platform_bus_type.dev_root);
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	of_iommu_set_ops(np, &exynos_iommu_ops);
+	return 0;
+}
+
+IOMMU_OF_DECLARE(exynos_iommu_of, "samsung,exynos-sysmmu",
+		 exynos_iommu_of_setup);