dm: core: Introduce xxx_translate_dma_address()

Add the following functions to translate DMA address to CPU address:
- dev_translate_dma_address()
- ofnode_translate_dma_address()
- of_translate_dma_address()
- fdt_translate_dma_address()
These functions work the same way as xxx_translate_address(), with the
difference that the translation relies on the "dma-ranges" property
instead of the "ranges" property.

Add related test. Test report:
=> ut dm fdt_translation
Test: dm_test_fdt_translation: test-fdt.c
Test: dm_test_fdt_translation: test-fdt.c (flat tree)
Failures: 0

Signed-off-by: Fabien Dessenne <fabien.dessenne@st.com>

4 files changed, 76 insertions, 2 deletions

diff --git a/include/dm/of_addr.h b/include/dm/of_addr.h
index 12b1a99..3fa1ffc 100644
--- a/include/dm/of_addr.h
+++ b/include/dm/of_addr.h
@@ -27,6 +27,24 @@
 u64 of_translate_address(const struct device_node *no, const __be32 *in_addr);
 
 /**
+ * of_translate_dma_address() - translate a device-tree DMA address to a CPU
+ *				address
+ *
+ * Translate a DMA address from the device-tree into a CPU physical address,
+ * this walks up the tree and applies the various bus mappings on the way.
+ *
+ * Note: We consider that crossing any level with #size-cells == 0 to mean
+ * that translation is impossible (that is we are not dealing with a value
+ * that can be mapped to a cpu physical address). This is not really specified
+ * that way, but this is traditionally the way IBM at least do things
+ *
+ * @np: node to check
+ * @in_addr: pointer to input DMA address
+ * @return translated DMA address or OF_BAD_ADDR on error
+ */
+u64 of_translate_dma_address(const struct device_node *no, const __be32 *in_addr);
+
+/**
  * of_get_address() - obtain an address from a node
  *
  * Extract an address from a node, returns the region size and the address
diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
index 704f915..4f89db44 100644
--- a/include/dm/ofnode.h
+++ b/include/dm/ofnode.h
@@ -767,7 +767,7 @@ ofnode ofnode_by_prop_value(ofnode from, const char *propname,
 	     node = ofnode_next_subnode(node))
 
 /**
- * ofnode_translate_address() - Tranlate a device-tree address
+ * ofnode_translate_address() - Translate a device-tree address
  *
  * Translate an address from the device-tree into a CPU physical address. This
  * function walks up the tree and applies the various bus mappings along the
@@ -781,6 +781,20 @@ ofnode ofnode_by_prop_value(ofnode from, const char *propname,
 u64 ofnode_translate_address(ofnode node, const fdt32_t *in_addr);
 
 /**
+ * ofnode_translate_dma_address() - Translate a device-tree DMA address
+ *
+ * Translate a DMA address from the device-tree into a CPU physical address.
+ * This function walks up the tree and applies the various bus mappings along
+ * the way.
+ *
+ * @ofnode: Device tree node giving the context in which to translate the
+ *          DMA address
+ * @in_addr: pointer to the DMA address to translate
+ * @return the translated DMA address; OF_BAD_ADDR on error
+ */
+u64 ofnode_translate_dma_address(ofnode node, const fdt32_t *in_addr);
+
+/**
  * ofnode_device_is_compatible() - check if the node is compatible with compat
  *
  * This allows to check whether the node is comaptible with the compat.
diff --git a/include/dm/read.h b/include/dm/read.h
index 60b727c..62d4be6 100644
--- a/include/dm/read.h
+++ b/include/dm/read.h
@@ -499,7 +499,7 @@ int dev_read_resource_byname(struct udevice *dev, const char *name,
 			     struct resource *res);
 
 /**
- * dev_translate_address() - Tranlate a device-tree address
+ * dev_translate_address() - Translate a device-tree address
  *
  * Translate an address from the device-tree into a CPU physical address.  This
  * function walks up the tree and applies the various bus mappings along the
@@ -512,6 +512,19 @@ int dev_read_resource_byname(struct udevice *dev, const char *name,
 u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_addr);
 
 /**
+ * dev_translate_dma_address() - Translate a device-tree DMA address
+ *
+ * Translate a DMA address from the device-tree into a CPU physical address.
+ * This function walks up the tree and applies the various bus mappings along
+ * the way.
+ *
+ * @dev: device giving the context in which to translate the DMA address
+ * @in_addr: pointer to the DMA address to translate
+ * @return the translated DMA address; OF_BAD_ADDR on error
+ */
+u64 dev_translate_dma_address(struct udevice *dev, const fdt32_t *in_addr);
+
+/**
  * dev_read_alias_highest_id - Get highest alias id for the given stem
  * @stem:	Alias stem to be examined
  *
@@ -751,6 +764,11 @@ static inline u64 dev_translate_address(struct udevice *dev, const fdt32_t *in_a
 	return ofnode_translate_address(dev_ofnode(dev), in_addr);
 }
 
+static inline u64 dev_translate_dma_address(struct udevice *dev, const fdt32_t *in_addr)
+{
+	return ofnode_translate_dma_address(dev_ofnode(dev), in_addr);
+}
+
 static inline int dev_read_alias_highest_id(const char *stem)
 {
 	return fdtdec_get_alias_highest_id(gd->fdt_blob, stem);
diff --git a/include/fdt_support.h b/include/fdt_support.h
index 27fe564..cefb2b2 100644
--- a/include/fdt_support.h
+++ b/include/fdt_support.h
@@ -218,8 +218,32 @@ static inline void fdt_fixup_mtdparts(void *fdt,
 #endif
 
 void fdt_del_node_and_alias(void *blob, const char *alias);
+
+/**
+ * Translate an address from the DT into a CPU physical address
+ *
+ * The translation relies on the "ranges" property.
+ *
+ * @param blob		Pointer to device tree blob
+ * @param node_offset	Node DT offset
+ * @param in_addr	Pointer to the address to translate
+ * @return translated address or OF_BAD_ADDR on error
+ */
 u64 fdt_translate_address(const void *blob, int node_offset,
 			  const __be32 *in_addr);
+/**
+ * Translate a DMA address from the DT into a CPU physical address
+ *
+ * The translation relies on the "dma-ranges" property.
+ *
+ * @param blob		Pointer to device tree blob
+ * @param node_offset	Node DT offset
+ * @param in_addr	Pointer to the DMA address to translate
+ * @return translated DMA address or OF_BAD_ADDR on error
+ */
+u64 fdt_translate_dma_address(const void *blob, int node_offset,
+			      const __be32 *in_addr);
+
 int fdt_node_offset_by_compat_reg(void *blob, const char *compat,
 					phys_addr_t compat_off);
 int fdt_alloc_phandle(void *blob);