1 files changed, 35 insertions, 75 deletions

diff --git a/drivers/of/device.c b/drivers/of/device.c
index de89f9906375..c80426510ec2 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -35,44 +35,35 @@ EXPORT_SYMBOL(of_match_device);
 static void
 of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
 {
-	struct device_node *node, *of_node = dev->of_node;
-	int count, i;
+	struct device_node *of_node = dev->of_node;
+	struct of_phandle_iterator it;
+	int rc, i = 0;
 
 	if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))
 		return;
 
-	count = of_property_count_elems_of_size(of_node, "memory-region",
-						sizeof(u32));
 	/*
 	 * If dev->of_node doesn't exist or doesn't contain memory-region, try
 	 * the OF node having DMA configuration.
 	 */
-	if (count <= 0) {
+	if (!of_property_present(of_node, "memory-region"))
 		of_node = np;
-		count = of_property_count_elems_of_size(
-			of_node, "memory-region", sizeof(u32));
-	}
 
-	for (i = 0; i < count; i++) {
-		node = of_parse_phandle(of_node, "memory-region", i);
+	of_for_each_phandle(&it, rc, of_node, "memory-region", NULL, 0) {
 		/*
 		 * There might be multiple memory regions, but only one
 		 * restricted-dma-pool region is allowed.
 		 */
-		if (of_device_is_compatible(node, "restricted-dma-pool") &&
-		    of_device_is_available(node)) {
-			of_node_put(node);
+		if (of_device_is_compatible(it.node, "restricted-dma-pool") &&
+		    of_device_is_available(it.node)) {
+			if (of_reserved_mem_device_init_by_idx(dev, of_node, i))
+				dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
+			of_node_put(it.node);
 			break;
 		}
-		of_node_put(node);
+		i++;
 	}
 
-	/*
-	 * Attempt to initialize a restricted-dma-pool region if one was found.
-	 * Note that count can hold a negative error code.
-	 */
-	if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i))
-		dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
 }
 
 /**
@@ -95,12 +86,15 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 {
 	const struct bus_dma_region *map = NULL;
 	struct device_node *bus_np;
-	u64 dma_start = 0;
-	u64 mask, end, size = 0;
-	bool coherent;
-	int iommu_ret;
+	u64 mask, end = 0;
+	bool coherent, set_map = false;
 	int ret;
 
+	if (dev->dma_range_map) {
+		dev_dbg(dev, "dma_range_map already set\n");
+		goto skip_map;
+	}
+
 	if (np == dev->of_node)
 		bus_np = __of_get_dma_parent(np);
 	else
@@ -117,36 +111,11 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 		if (!force_dma)
 			return ret == -ENODEV ? 0 : ret;
 	} else {
-		const struct bus_dma_region *r = map;
-		u64 dma_end = 0;
-
 		/* Determine the overall bounds of all DMA regions */
-		for (dma_start = ~0; r->size; r++) {
-			/* Take lower and upper limits */
-			if (r->dma_start < dma_start)
-				dma_start = r->dma_start;
-			if (r->dma_start + r->size > dma_end)
-				dma_end = r->dma_start + r->size;
-		}
-		size = dma_end - dma_start;
-
-		/*
-		 * Add a work around to treat the size as mask + 1 in case
-		 * it is defined in DT as a mask.
-		 */
-		if (size & 1) {
-			dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",
-				 size);
-			size = size + 1;
-		}
-
-		if (!size) {
-			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
-			kfree(map);
-			return -EINVAL;
-		}
+		end = dma_range_map_max(map);
+		set_map = true;
 	}
-
+skip_map:
 	/*
 	 * If @dev is expected to be DMA-capable then the bus code that created
 	 * it should have initialised its dma_mask pointer by this point. For
@@ -158,21 +127,20 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 		dev->dma_mask = &dev->coherent_dma_mask;
 	}
 
-	if (!size && dev->coherent_dma_mask)
-		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
-	else if (!size)
-		size = 1ULL << 32;
+	if (!end && dev->coherent_dma_mask)
+		end = dev->coherent_dma_mask;
+	else if (!end)
+		end = (1ULL << 32) - 1;
 
 	/*
 	 * Limit coherent and dma mask based on size and default mask
 	 * set by the driver.
 	 */
-	end = dma_start + size - 1;
 	mask = DMA_BIT_MASK(ilog2(end) + 1);
 	dev->coherent_dma_mask &= mask;
 	*dev->dma_mask &= mask;
 	/* ...but only set bus limit and range map if we found valid dma-ranges earlier */
-	if (!ret) {
+	if (set_map) {
 		dev->bus_dma_limit = end;
 		dev->dma_range_map = map;
 	}
@@ -181,29 +149,21 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
 	dev_dbg(dev, "device is%sdma coherent\n",
 		coherent ? " " : " not ");
 
-	iommu_ret = of_iommu_configure(dev, np, id);
-	if (iommu_ret == -EPROBE_DEFER) {
+	ret = of_iommu_configure(dev, np, id);
+	if (ret == -EPROBE_DEFER) {
 		/* Don't touch range map if it wasn't set from a valid dma-ranges */
-		if (!ret)
+		if (set_map)
 			dev->dma_range_map = NULL;
 		kfree(map);
 		return -EPROBE_DEFER;
-	} else if (iommu_ret == -ENODEV) {
-		dev_dbg(dev, "device is not behind an iommu\n");
-	} else if (iommu_ret) {
-		dev_err(dev, "iommu configuration for device failed with %pe\n",
-			ERR_PTR(iommu_ret));
-
-		/*
-		 * Historically this routine doesn't fail driver probing
-		 * due to errors in of_iommu_configure()
-		 */
-	} else
-		dev_dbg(dev, "device is behind an iommu\n");
+	}
+	/* Take all other IOMMU errors to mean we'll just carry on without it */
+	dev_dbg(dev, "device is%sbehind an iommu\n",
+		!ret ? " " : " not ");
 
-	arch_setup_dma_ops(dev, dma_start, size, coherent);
+	arch_setup_dma_ops(dev, coherent);
 
-	if (iommu_ret)
+	if (ret)
 		of_dma_set_restricted_buffer(dev, np);
 
 	return 0;