Add Peer target support

Author: deepakala-k

libpdbg/device.c

@@ -657,6 +657,36 @@ static void dt_link_virtual(struct pdbg_target *node, struct pdbg_target *vnode)
 	vnode->vnode = node;
 }
 
+static void dt_link_peer(struct pdbg_target *node, struct pdbg_target *pnode)
+{
+	node->pnode = pnode;
+	pnode->pnode = node;
+}
+
+
+static void pdbg_targets_init_peer(struct pdbg_target *node, struct pdbg_target *root)
+{
+	struct pdbg_target *child = NULL;
+	
+	/* Skip virtual nodes */
+	if (target_is_virtual(node))
+		goto skip;
+
+	struct pdbg_target *pnode = NULL;
+	pnode = pdbg_get_peer_target(node);
+
+	if (!pnode)
+		goto skip;
+
+	dt_link_peer(node, pnode);
+
+skip:
+	list_for_each(&node->children, child, list) {
+		pdbg_targets_init_peer(child, root);
+	}
+}
+
+
 static void pdbg_targets_init_virtual(struct pdbg_target *node, struct pdbg_target *root)
 {
 	struct pdbg_target *vnode, *child = NULL;
@@ -803,6 +833,8 @@ bool pdbg_targets_init(void *fdt)
 
 	pdbg_targets_init_virtual(pdbg_dt_root, pdbg_dt_root);
 
+	pdbg_targets_init_peer(pdbg_dt_root, pdbg_dt_root);
+
 	//Close any FDs which might be still opened
 	close(dtb->system.fd);
 	close(dtb->backend.fd);

libpdbg/libpdbg.c

@@ -7,6 +7,19 @@
 static pdbg_progress_tick_t progress_tick;
 static bool pdbg_short_context = false;
 
+#define MAX_PEER_TYPE_ENTRIES 3  
+
+typedef struct {
+    char key[120];
+    char value[120];
+} peer_map_struct;
+
+peer_map_struct peer_map[MAX_PEER_TYPE_ENTRIES] = {
+    {"tbusl", "tbusl"},
+    {"core", "l3cache"},
+    {"l3cache", "core"},
+};
+
 struct pdbg_target *get_parent(struct pdbg_target *target, bool system)
 {
 	struct pdbg_target *parent;
@@ -359,3 +372,72 @@ bool pdbg_context_is_short(void)
 {
 	return pdbg_short_context;
 }
+
+char* extract_string_after_colon(char* input) 
+{
+    // Find the position of ':'
+    char* pos = strchr(input, ':');
+	// Return pointer to substring after ':'
+    if (pos != NULL && *(pos + 1) != '\0') {
+        return pos + 1; 
+    }
+	// Return empty string if ':' is not found or nothing follows it
+    return ""; 
+}
+
+
+// Function to get peer class name
+const char* get_peer_class_name(const char *key) {
+
+    for (int i = 0; i < MAX_PEER_TYPE_ENTRIES; i++) {
+        if (strcmp(peer_map[i].key, key) == 0) {
+            return peer_map[i].value;
+        }
+    }
+    return NULL;  // Key not found
+}
+
+struct pdbg_target *pdbg_get_pnode(struct pdbg_target *target)
+{
+	return target->pnode;
+}
+
+struct pdbg_target *pdbg_get_peer_target(struct pdbg_target *target)
+{
+	//Get the class type to find its appropriate peer
+	const char* peer_class_name = get_peer_class_name(target->class);
+
+	//As get attr is an expensive operation, check if the current class
+	//is expected to have a peer class
+	if(peer_class_name)
+	{
+		char tgtPeerPath[120];
+		if (!pdbg_target_get_attribute(target, "ATTR_PEER_PATH", 1, 120,
+					tgtPeerPath)) {
+						//unable to find the path
+						pdbg_log(PDBG_ERROR, "unable to find the attribute ATTR_PEER_PATH for %s\n", 
+							pdbg_target_path(target));
+		}
+		else
+		{
+			struct pdbg_target *traversed_target;
+			//The peer could only be of the same type, so look for all the targets of that type
+			pdbg_for_each_class_target(peer_class_name, traversed_target)
+			{
+				char tgtPhyPath[120];
+				if (pdbg_target_get_attribute(traversed_target, "ATTR_PHYS_DEV_PATH", 1, 120,
+							tgtPhyPath)) {
+					//unable to find the path
+					if( strcmp(extract_string_after_colon(tgtPhyPath), extract_string_after_colon(tgtPeerPath)) == 0)
+					{
+						return traversed_target;
+					}
+				}
+			}
+			
+		}
+		pdbg_log(PDBG_ERROR, "unable to find the peer target for %s\n", 
+			pdbg_target_path(target));
+	}
+	return NULL;
+}

libpdbg/libpdbg.h

@@ -1530,6 +1530,20 @@ bool pdbg_context_short(void);
  */
 void pdbg_release_dt_root();
 
+/**
+ * @brief Find a peer target of the given class
+ * @param[in] target the pdbg_target
+ * @return struct pdbg_target* of the peer class
+ */
+struct pdbg_target *pdbg_get_peer_target(struct pdbg_target *target);
+
+/**
+ * @brief Helper method to return the peer node of the target
+ * @param[in] target the pdbg_target
+ * @return struct pdbg_target* of the peer class
+ */
+struct pdbg_target *pdbg_get_pnode(struct pdbg_target *target);
+
 #ifdef __cplusplus
 }
 #endif

libpdbg/target.h

@@ -62,6 +62,7 @@ struct pdbg_target {
 	struct list_node class_link;
 	void *priv;
 	struct pdbg_target *vnode;
+	struct pdbg_target *pnode;
 };
 
 struct pdbg_mfile {