1 files changed, 251 insertions, 70 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5c5427918eb..865d3f66c86 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -18,6 +18,7 @@
  *      2 of the License, or (at your option) any later version.
  */
 #include <linux/ctype.h>
+#include <linux/cpu.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/spinlock.h>
@@ -32,6 +33,7 @@ struct device_node *of_allnodes;
 EXPORT_SYMBOL(of_allnodes);
 struct device_node *of_chosen;
 struct device_node *of_aliases;
+static struct device_node *of_stdout;
 
 DEFINE_MUTEX(of_aliases_mutex);
 
@@ -230,6 +232,100 @@ const void *of_get_property(const struct device_node *np, const char *name,
 }
 EXPORT_SYMBOL(of_get_property);
 
+/*
+ * arch_match_cpu_phys_id - Match the given logical CPU and physical id
+ *
+ * @cpu: logical cpu index of a core/thread
+ * @phys_id: physical identifier of a core/thread
+ *
+ * CPU logical to physical index mapping is architecture specific.
+ * However this __weak function provides a default match of physical
+ * id to logical cpu index. phys_id provided here is usually values read
+ * from the device tree which must match the hardware internal registers.
+ *
+ * Returns true if the physical identifier and the logical cpu index
+ * correspond to the same core/thread, false otherwise.
+ */
+bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id)
+{
+	return (u32)phys_id == cpu;
+}
+
+/**
+ * Checks if the given "prop_name" property holds the physical id of the
+ * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not
+ * NULL, local thread number within the core is returned in it.
+ */
+static bool __of_find_n_match_cpu_property(struct device_node *cpun,
+			const char *prop_name, int cpu, unsigned int *thread)
+{
+	const __be32 *cell;
+	int ac, prop_len, tid;
+	u64 hwid;
+
+	ac = of_n_addr_cells(cpun);
+	cell = of_get_property(cpun, prop_name, &prop_len);
+	if (!cell)
+		return false;
+	prop_len /= sizeof(*cell);
+	for (tid = 0; tid < prop_len; tid++) {
+		hwid = of_read_number(cell, ac);
+		if (arch_match_cpu_phys_id(cpu, hwid)) {
+			if (thread)
+				*thread = tid;
+			return true;
+		}
+		cell += ac;
+	}
+	return false;
+}
+
+/**
+ * of_get_cpu_node - Get device node associated with the given logical CPU
+ *
+ * @cpu: CPU number(logical index) for which device node is required
+ * @thread: if not NULL, local thread number within the physical core is
+ *          returned
+ *
+ * The main purpose of this function is to retrieve the device node for the
+ * given logical CPU index. It should be used to initialize the of_node in
+ * cpu device. Once of_node in cpu device is populated, all the further
+ * references can use that instead.
+ *
+ * CPU logical to physical index mapping is architecture specific and is built
+ * before booting secondary cores. This function uses arch_match_cpu_phys_id
+ * which can be overridden by architecture specific implementation.
+ *
+ * Returns a node pointer for the logical cpu if found, else NULL.
+ */
+struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
+{
+	struct device_node *cpun, *cpus;
+
+	cpus = of_find_node_by_path("/cpus");
+	if (!cpus) {
+		pr_warn("Missing cpus node, bailing out\n");
+		return NULL;
+	}
+
+	for_each_child_of_node(cpus, cpun) {
+		if (of_node_cmp(cpun->type, "cpu"))
+			continue;
+		/* Check for non-standard "ibm,ppc-interrupt-server#s" property
+		 * for thread ids on PowerPC. If it doesn't exist fallback to
+		 * standard "reg" property.
+		 */
+		if (IS_ENABLED(CONFIG_PPC) &&
+			__of_find_n_match_cpu_property(cpun,
+				"ibm,ppc-interrupt-server#s", cpu, thread))
+			return cpun;
+		if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread))
+			return cpun;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(of_get_cpu_node);
+
 /** Checks if the given "compat" string matches one of the strings in
  * the device's "compatible" property
  */
@@ -1080,65 +1176,10 @@ int of_property_count_strings(struct device_node *np, const char *propname)
 }
 EXPORT_SYMBOL_GPL(of_property_count_strings);
 
-/**
- * of_parse_phandle - Resolve a phandle property to a device_node pointer
- * @np: Pointer to device node holding phandle property
- * @phandle_name: Name of property holding a phandle value
- * @index: For properties holding a table of phandles, this is the index into
- *         the table
- *
- * Returns the device_node pointer with refcount incremented.  Use
- * of_node_put() on it when done.
- */
-struct device_node *of_parse_phandle(const struct device_node *np,
-				     const char *phandle_name, int index)
-{
-	const __be32 *phandle;
-	int size;
-
-	phandle = of_get_property(np, phandle_name, &size);
-	if ((!phandle) || (size < sizeof(*phandle) * (index + 1)))
-		return NULL;
-
-	return of_find_node_by_phandle(be32_to_cpup(phandle + index));
-}
-EXPORT_SYMBOL(of_parse_phandle);
-
-/**
- * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
- * @np:		pointer to a device tree node containing a list
- * @list_name:	property name that contains a list
- * @cells_name:	property name that specifies phandles' arguments count
- * @index:	index of a phandle to parse out
- * @out_args:	optional pointer to output arguments structure (will be filled)
- *
- * This function is useful to parse lists of phandles and their arguments.
- * Returns 0 on success and fills out_args, on error returns appropriate
- * errno value.
- *
- * Caller is responsible to call of_node_put() on the returned out_args->node
- * pointer.
- *
- * Example:
- *
- * phandle1: node1 {
- * 	#list-cells = <2>;
- * }
- *
- * phandle2: node2 {
- * 	#list-cells = <1>;
- * }
- *
- * node3 {
- * 	list = <&phandle1 1 2 &phandle2 3>;
- * }
- *
- * To get a device_node of the `node2' node you may call this:
- * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
- */
 static int __of_parse_phandle_with_args(const struct device_node *np,
 					const char *list_name,
-					const char *cells_name, int index,
+					const char *cells_name,
+					int cell_count, int index,
 					struct of_phandle_args *out_args)
 {
 	const __be32 *list, *list_end;
@@ -1166,19 +1207,32 @@ static int __of_parse_phandle_with_args(const struct device_node *np,
 		if (phandle) {
 			/*
 			 * Find the provider node and parse the #*-cells
-			 * property to determine the argument length
+			 * property to determine the argument length.
+			 *
+			 * This is not needed if the cell count is hard-coded
+			 * (i.e. cells_name not set, but cell_count is set),
+			 * except when we're going to return the found node
+			 * below.
 			 */
-			node = of_find_node_by_phandle(phandle);
-			if (!node) {
-				pr_err("%s: could not find phandle\n",
-					 np->full_name);
-				goto err;
+			if (cells_name || cur_index == index) {
+				node = of_find_node_by_phandle(phandle);
+				if (!node) {
+					pr_err("%s: could not find phandle\n",
+						np->full_name);
+					goto err;
+				}
 			}
-			if (of_property_read_u32(node, cells_name, &count)) {
-				pr_err("%s: could not get %s for %s\n",
-					 np->full_name, cells_name,
-					 node->full_name);
-				goto err;
+
+			if (cells_name) {
+				if (of_property_read_u32(node, cells_name,
+							 &count)) {
+					pr_err("%s: could not get %s for %s\n",
+						np->full_name, cells_name,
+						node->full_name);
+					goto err;
+				}
+			} else {
+				count = cell_count;
 			}
 
 			/*
@@ -1238,17 +1292,117 @@ static int __of_parse_phandle_with_args(const struct device_node *np,
 	return rc;
 }
 
+/**
+ * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * @np: Pointer to device node holding phandle property
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ *         the table
+ *
+ * Returns the device_node pointer with refcount incremented.  Use
+ * of_node_put() on it when done.
+ */
+struct device_node *of_parse_phandle(const struct device_node *np,
+				     const char *phandle_name, int index)
+{
+	struct of_phandle_args args;
+
+	if (index < 0)
+		return NULL;
+
+	if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0,
+					 index, &args))
+		return NULL;
+
+	return args.np;
+}
+EXPORT_SYMBOL(of_parse_phandle);
+
+/**
+ * of_parse_phandle_with_args() - Find a node pointed by phandle in a list
+ * @np:		pointer to a device tree node containing a list
+ * @list_name:	property name that contains a list
+ * @cells_name:	property name that specifies phandles' arguments count
+ * @index:	index of a phandle to parse out
+ * @out_args:	optional pointer to output arguments structure (will be filled)
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_args, on error returns appropriate
+ * errno value.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->node
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * 	#list-cells = <2>;
+ * }
+ *
+ * phandle2: node2 {
+ * 	#list-cells = <1>;
+ * }
+ *
+ * node3 {
+ * 	list = <&phandle1 1 2 &phandle2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args);
+ */
 int of_parse_phandle_with_args(const struct device_node *np, const char *list_name,
 				const char *cells_name, int index,
 				struct of_phandle_args *out_args)
 {
 	if (index < 0)
 		return -EINVAL;
-	return __of_parse_phandle_with_args(np, list_name, cells_name, index, out_args);
+	return __of_parse_phandle_with_args(np, list_name, cells_name, 0,
+					    index, out_args);
 }
 EXPORT_SYMBOL(of_parse_phandle_with_args);
 
 /**
+ * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list
+ * @np:		pointer to a device tree node containing a list
+ * @list_name:	property name that contains a list
+ * @cell_count: number of argument cells following the phandle
+ * @index:	index of a phandle to parse out
+ * @out_args:	optional pointer to output arguments structure (will be filled)
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_args, on error returns appropriate
+ * errno value.
+ *
+ * Caller is responsible to call of_node_put() on the returned out_args->node
+ * pointer.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * }
+ *
+ * phandle2: node2 {
+ * }
+ *
+ * node3 {
+ * 	list = <&phandle1 0 2 &phandle2 2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args);
+ */
+int of_parse_phandle_with_fixed_args(const struct device_node *np,
+				const char *list_name, int cell_count,
+				int index, struct of_phandle_args *out_args)
+{
+	if (index < 0)
+		return -EINVAL;
+	return __of_parse_phandle_with_args(np, list_name, NULL, cell_count,
+					   index, out_args);
+}
+EXPORT_SYMBOL(of_parse_phandle_with_fixed_args);
+
+/**
  * of_count_phandle_with_args() - Find the number of phandles references in a property
  * @np:		pointer to a device tree node containing a list
  * @list_name:	property name that contains a list
@@ -1266,7 +1420,8 @@ EXPORT_SYMBOL(of_parse_phandle_with_args);
 int of_count_phandle_with_args(const struct device_node *np, const char *list_name,
 				const char *cells_name)
 {
-	return __of_parse_phandle_with_args(np, list_name, cells_name, -1, NULL);
+	return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1,
+					    NULL);
 }
 EXPORT_SYMBOL(of_count_phandle_with_args);
 
@@ -1595,6 +1750,15 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 	of_chosen = of_find_node_by_path("/chosen");
 	if (of_chosen == NULL)
 		of_chosen = of_find_node_by_path("/chosen@0");
+
+	if (of_chosen) {
+		const char *name;
+
+		name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+		if (name)
+			of_stdout = of_find_node_by_path(name);
+	}
+
 	of_aliases = of_find_node_by_path("/aliases");
 	if (!of_aliases)
 		return;
@@ -1629,6 +1793,7 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 		ap = dt_alloc(sizeof(*ap) + len + 1, 4);
 		if (!ap)
 			continue;
+		memset(ap, 0, sizeof(*ap) + len + 1);
 		ap->alias = start;
 		of_alias_add(ap, np, id, start, len);
 	}
@@ -1703,3 +1868,19 @@ const char *of_prop_next_string(struct property *prop, const char *cur)
 	return curv;
 }
 EXPORT_SYMBOL_GPL(of_prop_next_string);
+
+/**
+ * of_device_is_stdout_path - check if a device node matches the
+ *                            linux,stdout-path property
+ *
+ * Check if this device node matches the linux,stdout-path property
+ * in the chosen node. return true if yes, false otherwise.
+ */
+int of_device_is_stdout_path(struct device_node *dn)
+{
+	if (!of_stdout)
+		return false;
+
+	return of_stdout == dn;
+}
+EXPORT_SYMBOL_GPL(of_device_is_stdout_path);