1 files changed, 46 insertions, 0 deletions

diff --git a/arch/powerpc/mm/drmem.c b/arch/powerpc/mm/drmem.c
index 9af3832c9d8d..22197b18d85e 100644
--- a/arch/powerpc/mm/drmem.c
+++ b/arch/powerpc/mm/drmem.c
@@ -18,6 +18,7 @@ static int n_root_addr_cells, n_root_size_cells;
 
 static struct drmem_lmb_info __drmem_info;
 struct drmem_lmb_info *drmem_info = &__drmem_info;
+static bool in_drmem_update;
 
 u64 drmem_lmb_memory_max(void)
 {
@@ -178,6 +179,11 @@ int drmem_update_dt(void)
 	if (!memory)
 		return -1;
 
+	/*
+	 * Set in_drmem_update to prevent the notifier callback to process the
+	 * DT property back since the change is coming from the LMB tree.
+	 */
+	in_drmem_update = true;
 	prop = of_find_property(memory, "ibm,dynamic-memory", NULL);
 	if (prop) {
 		rc = drmem_update_dt_v1(memory, prop);
@@ -186,6 +192,7 @@ int drmem_update_dt(void)
 		if (prop)
 			rc = drmem_update_dt_v2(memory, prop);
 	}
+	in_drmem_update = false;
 
 	of_node_put(memory);
 	return rc;
@@ -307,6 +314,45 @@ int __init walk_drmem_lmbs_early(unsigned long node, void *data,
 	return ret;
 }
 
+/*
+ * Update the LMB associativity index.
+ */
+static int update_lmb(struct drmem_lmb *updated_lmb,
+		      __maybe_unused const __be32 **usm,
+		      __maybe_unused void *data)
+{
+	struct drmem_lmb *lmb;
+
+	for_each_drmem_lmb(lmb) {
+		if (lmb->drc_index != updated_lmb->drc_index)
+			continue;
+
+		lmb->aa_index = updated_lmb->aa_index;
+		break;
+	}
+	return 0;
+}
+
+/*
+ * Update the LMB associativity index.
+ *
+ * This needs to be called when the hypervisor is updating the
+ * dynamic-reconfiguration-memory node property.
+ */
+void drmem_update_lmbs(struct property *prop)
+{
+	/*
+	 * Don't update the LMBs if triggered by the update done in
+	 * drmem_update_dt(), the LMB values have been used to the update the DT
+	 * property in that case.
+	 */
+	if (in_drmem_update)
+		return;
+	if (!strcmp(prop->name, "ibm,dynamic-memory"))
+		__walk_drmem_v1_lmbs(prop->value, NULL, NULL, update_lmb);
+	else if (!strcmp(prop->name, "ibm,dynamic-memory-v2"))
+		__walk_drmem_v2_lmbs(prop->value, NULL, NULL, update_lmb);
+}
 #endif
 
 static int init_drmem_lmb_size(struct device_node *dn)