res->start += rule->align;
                res->end = res->start + rule->size - 1;
                if (res->start > rule->max || !rule->align) {
-                       dev_dbg(&dev->dev, "  couldn't assign io %d\n", idx);
+                       dev_dbg(&dev->dev, "  couldn't assign io %d "
+                               "(min %#llx max %#llx)\n", idx,
+                               (unsigned long long) rule->min,
+                               (unsigned long long) rule->max);
                        return 0;
                }
        }
                res->start += rule->align;
                res->end = res->start + rule->size - 1;
                if (res->start > rule->max || !rule->align) {
-                       dev_dbg(&dev->dev, "  couldn't assign mem %d\n", idx);
+                       dev_dbg(&dev->dev, "  couldn't assign mem %d "
+                               "(min %#llx max %#llx)\n", idx,
+                               (unsigned long long) rule->min,
+                               (unsigned long long) rule->max);
                        return 0;
                }
        }