commit 9aaa1a625da9de1ca758c4eb8442589b46927acb
Author: Haren Myneni <haren@linux.ibm.com>
Date:   Tue Aug 13 14:40:24 2024 -0700

    drmgr/phb: Add kernel interface support for device tree update
    
    Use the following kernel interfaces for PHB device type to update
    the device tree if this feature is enabled in the kernel.
    
    dt add index <DRC index>  --> for IO add
    dt remove index <DRC index> --> for IO remove
    
    Signed-off-by: Haren Myneni <haren@linux.ibm.com>
    Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>

diff --git a/src/drmgr/common_pci.c b/src/drmgr/common_pci.c
index 109e0d2..683d72d 100644
--- a/src/drmgr/common_pci.c
+++ b/src/drmgr/common_pci.c
@@ -1390,7 +1390,6 @@ print_node_list(struct dr_node *first_node)
 static int
 acquire_hp_resource(struct dr_connector *drc, char *of_path)
 {
-	struct of_node *new_nodes;
 	int state;
 	int rc;
 
@@ -1429,12 +1428,21 @@ acquire_hp_resource(struct dr_connector *drc, char *of_path)
 	}
 
 	if (state == PRESENT) {
-		new_nodes = configure_connector(drc->index);
-		if (new_nodes == NULL)
-			return -1;
+		/*
+		 * Use kernel DLPAR interface if it is enabled
+		 */
+		if (kernel_dlpar_exists()) {
+			rc = do_dt_kernel_dlpar(drc->index, ADD);
+		} else {
+			struct of_node *new_nodes;
+
+			new_nodes = configure_connector(drc->index);
+			if (new_nodes == NULL)
+				return -1;
 
-		rc = add_device_tree_nodes(of_path, new_nodes);
-		free_of_node(new_nodes);
+			rc = add_device_tree_nodes(of_path, new_nodes);
+			free_of_node(new_nodes);
+		}
 		if (rc) {
 			say(ERROR, "add nodes failed for 0x%x\n", drc->index);
 			return rc;
@@ -1490,7 +1498,14 @@ release_hp_resource(struct dr_node *node)
 {
 	int rc;
 
-	rc = remove_device_tree_nodes(node->ofdt_path);
+	/*
+	 * Use kernel DLPAR interface if it is enabled
+	 */
+	if (kernel_dlpar_exists())
+		rc = do_dt_kernel_dlpar(node->drc_index, REMOVE);
+	else
+		rc = remove_device_tree_nodes(node->ofdt_path);
+
 	if (rc) {
 		say(ERROR, "failed to remove kernel nodes for index 0x%x\n",
 		    node->drc_index);
diff --git a/src/drmgr/drslot_chrp_phb.c b/src/drmgr/drslot_chrp_phb.c
index 220d844..5bf3030 100644
--- a/src/drmgr/drslot_chrp_phb.c
+++ b/src/drmgr/drslot_chrp_phb.c
@@ -108,17 +108,16 @@ release_phb(struct dr_node *phb)
 {
 	int rc;
 
-	rc = remove_device_tree_nodes(phb->ofdt_path);
-	if (rc)
-		return rc;
-
-	if (phb->phb_ic_ofdt_path[0] != '\0') {
-		rc = remove_device_tree_nodes(phb->phb_ic_ofdt_path);
-		if (rc)
-			return rc;
+	if (kernel_dlpar_exists())
+		rc = do_dt_kernel_dlpar(phb->drc_index, REMOVE);
+	else {
+		rc = remove_device_tree_nodes(phb->ofdt_path);
+		if (!rc && (phb->phb_ic_ofdt_path[0] != '\0'))
+			rc = remove_device_tree_nodes(phb->phb_ic_ofdt_path);
 	}
 
-	rc = release_drc(phb->drc_index, PHB_DEV);
+	if (!rc)
+		rc = release_drc(phb->drc_index, PHB_DEV);
 
 	return rc;
 }
@@ -390,7 +389,6 @@ phb_remove_error:
 static int acquire_phb(char *drc_name, struct dr_node **phb)
 {
 	struct dr_connector drc;
-	struct of_node *of_nodes;
 	char path[DR_PATH_MAX];
 	int rc;
 
@@ -405,14 +403,20 @@ static int acquire_phb(char *drc_name, struct dr_node **phb)
 	if (rc)
 		return rc;
 
-	of_nodes = configure_connector(drc.index);
-	if (of_nodes == NULL) {
-		release_drc(drc.index, PHB_DEV);
-		return -1;
-	}
+	if (kernel_dlpar_exists()) {
+		rc = do_dt_kernel_dlpar(drc.index, ADD);
+	} else {
+		struct of_node *of_nodes;
 
-	rc = add_device_tree_nodes(path, of_nodes);
-	free_of_node(of_nodes);
+		of_nodes = configure_connector(drc.index);
+		if (of_nodes == NULL) {
+			release_drc(drc.index, PHB_DEV);
+			return -1;
+		}
+
+		rc = add_device_tree_nodes(path, of_nodes);
+		free_of_node(of_nodes);
+	}
 	if (rc) {
 		say(ERROR, "add_device_tree_nodes failed at %s\n", path);
 		release_drc(drc.index, PHB_DEV);