4 files changed, 83 insertions, 0 deletions
diff --git a/src/commonlib/Makefile.inc b/src/commonlib/Makefile.inc
index 4d89c48e5a35..b6e8913cd101 100644
--- a/src/commonlib/Makefile.inc
+++ b/src/commonlib/Makefile.inc
@@ -36,3 +36,5 @@ verstage-y += lz4_wrapper.c
 romstage-y += lz4_wrapper.c
 ramstage-y += lz4_wrapper.c
 postcar-y += lz4_wrapper.c
+
+ramstage-y += sort.c
diff --git a/src/commonlib/include/commonlib/helpers.h b/src/commonlib/include/commonlib/helpers.h
index 03f430635d39..adc43ca98b62 100644
--- a/src/commonlib/include/commonlib/helpers.h
+++ b/src/commonlib/include/commonlib/helpers.h
@@ -38,6 +38,11 @@
 #define ABS(a) (((a) < 0) ? (-(a)) : (a))
 #define IS_POWER_OF_2(x)  (((x) & ((x) - 1)) == 0)
 #define DIV_ROUND_UP(x, y)  (((x) + (y) - 1) / (y))
+#define SWAP(a, b)	do { \
+				typeof(a) tmp = a; \
+				a = (typeof(a)) b; \
+				b = (typeof(b)) tmp; \
+			} while (0)
 /*
  * Divide positive or negative dividend by positive divisor and round
  * to closest integer. Result is undefined for negative divisors and
diff --git a/src/commonlib/include/commonlib/sort.h b/src/commonlib/include/commonlib/sort.h
new file mode 100644
index 000000000000..3d94d25d4029
--- /dev/null
+++ b/src/commonlib/include/commonlib/sort.h
@@ -0,0 +1,27 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 Siemens AG
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#ifndef _COMMONLIB_SORT_H_
+#define _COMMONLIB_SORT_H_
+
+#include <stddef.h>
+
+typedef enum {
+	NUM_ASCENDING,
+	NUM_DESCENDING
+} sort_order_t;
+
+void bubblesort(int *v, size_t num_entries, sort_order_t order);
+
+#endif /* _COMMONLIB_SORT_H_ */
diff --git a/src/commonlib/sort.c b/src/commonlib/sort.c
new file mode 100644
index 000000000000..40999397c876
--- /dev/null
+++ b/src/commonlib/sort.c
@@ -0,0 +1,49 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2019 Siemens AG
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <commonlib/helpers.h>
+#include <commonlib/sort.h>
+
+/* Implement a simple Bubble sort algorithm. Reduce the needed number of
+   iterations by taking care of already sorted entries in the list. */
+void bubblesort(int *v, size_t num_entries, sort_order_t order)
+{
+	size_t i, j;
+	int swapped;
+
+	for (j = 0; j < num_entries - 1; j++) {
+		swapped = 0;
+		for (i = 0; i < num_entries - j - 1; i++) {
+			switch (order) {
+			case NUM_ASCENDING:
+				if (v[i] > v[i + 1]) {
+					SWAP(v[i], v[i + 1]);
+					swapped = 1;
+				}
+				break;
+			case NUM_DESCENDING:
+				if (v[i] < v[i + 1]) {
+					SWAP(v[i], v[i + 1]);
+					swapped = 1;
+				}
+				break;
+			default:
+				return;
+			}
+		}
+		if (!swapped)
+			break;
+	}
+}