diff --git a/src/mainboard/system76/kbl-u/Makefile.inc b/src/mainboard/system76/kbl-u/Makefile.inc
index 5ffe936e09..e9e47a7ff0 100644
--- a/src/mainboard/system76/kbl-u/Makefile.inc
+++ b/src/mainboard/system76/kbl-u/Makefile.inc
@@ -1,2 +1 @@
-romstage-y += pei_data.c
-ramstage-y += ramstage.c pei_data.c variants/$(VARIANT_DIR)/hda_verb.c
+ramstage-y += ramstage.c variants/$(VARIANT_DIR)/hda_verb.c
diff --git a/src/mainboard/system76/kbl-u/pei_data.c b/src/mainboard/system76/kbl-u/pei_data.c
deleted file mode 100644
index f092f3eb15..0000000000
--- a/src/mainboard/system76/kbl-u/pei_data.c
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2019 System76
- *
- * 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 <stdint.h>
-#include <string.h>
-#include <soc/pei_data.h>
-#include <soc/pei_wrapper.h>
-#include "pei_data.h"
-
-void mainboard_fill_dq_map_data(void *dq_map_ptr) {
-	/* DQ byte map */
-	const u8 dq_map[2][12] = {
-		{0x0F, 0xF0, 0x00, 0xF0, 0x0F, 0xF0,
-		 0x0F, 0x00, 0xFF, 0x00, 0xFF, 0x00},
-		{0x33, 0xCC, 0x00, 0xCC, 0x33, 0xCC,
-		 0x33, 0x00, 0xFF, 0x00, 0xFF, 0x00}
-	};
-	memcpy(dq_map_ptr, dq_map, sizeof(dq_map));
-}
-
-void mainboard_fill_dqs_map_data(void *dqs_map_ptr) {
-	/* DQS CPU<>DRAM map */
-	const u8 dqs_map[2][8] = {
-		{0, 1, 2, 3, 4, 5, 6, 7},
-		{1, 0, 2, 3, 4, 5, 6, 7}
-	};
-	memcpy(dqs_map_ptr, dqs_map, sizeof(dqs_map));
-}
-
-void mainboard_fill_rcomp_res_data(void *rcomp_ptr) {
-	/* Rcomp resistor */
-	const u16 RcompResistor[3] = {121, 81, 100};
-	memcpy(rcomp_ptr, RcompResistor, sizeof(RcompResistor));
-}
-
-void mainboard_fill_rcomp_strength_data(void *rcomp_strength_ptr) {
-	/* Rcomp target */
-	const u16 RcompTarget[5] = {100, 40, 20, 20, 26};
-	memcpy(rcomp_strength_ptr, RcompTarget, sizeof(RcompTarget));
-}
-
-void mainboard_fill_pei_data(struct pei_data *pei_data) {
-	mainboard_fill_dq_map_data(&pei_data->dq_map);
-	mainboard_fill_dqs_map_data(&pei_data->dqs_map);
-	mainboard_fill_rcomp_res_data(&pei_data->RcompResistor);
-	mainboard_fill_rcomp_strength_data(&pei_data->RcompTarget);
-}
diff --git a/src/mainboard/system76/kbl-u/pei_data.h b/src/mainboard/system76/kbl-u/pei_data.h
deleted file mode 100644
index 9ad002319e..0000000000
--- a/src/mainboard/system76/kbl-u/pei_data.h
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- * Copyright (C) 2019 System76
- *
- * 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 _MAINBOARD_PEI_DATA_H_
-#define _MAINBOARD_PEI_DATA_H_
-
-void mainboard_fill_dq_map_data(void *dq_map_ptr);
-void mainboard_fill_dqs_map_data(void *dqs_map_ptr);
-void mainboard_fill_rcomp_res_data(void *rcomp_ptr);
-void mainboard_fill_rcomp_strength_data(void *rcomp_strength_ptr);
-
-#endif
diff --git a/src/mainboard/system76/kbl-u/romstage.c b/src/mainboard/system76/kbl-u/romstage.c
index 1537f96a2a..c10111f994 100644
--- a/src/mainboard/system76/kbl-u/romstage.c
+++ b/src/mainboard/system76/kbl-u/romstage.c
@@ -18,7 +18,38 @@
 #include <soc/romstage.h>
 #include <spd_bin.h>
 #include <arch/io.h>
-#include "pei_data.h"
+
+static void mainboard_fill_dq_map_data(void *dq_map_ptr) {
+	/* DQ byte map */
+	const u8 dq_map[2][12] = {
+		{0x0F, 0xF0, 0x00, 0xF0, 0x0F, 0xF0,
+		 0x0F, 0x00, 0xFF, 0x00, 0xFF, 0x00},
+		{0x33, 0xCC, 0x00, 0xCC, 0x33, 0xCC,
+		 0x33, 0x00, 0xFF, 0x00, 0xFF, 0x00}
+	};
+	memcpy(dq_map_ptr, dq_map, sizeof(dq_map));
+}
+
+static void mainboard_fill_dqs_map_data(void *dqs_map_ptr) {
+	/* DQS CPU<>DRAM map */
+	const u8 dqs_map[2][8] = {
+		{0, 1, 2, 3, 4, 5, 6, 7},
+		{1, 0, 2, 3, 4, 5, 6, 7}
+	};
+	memcpy(dqs_map_ptr, dqs_map, sizeof(dqs_map));
+}
+
+static void mainboard_fill_rcomp_res_data(void *rcomp_ptr) {
+	/* Rcomp resistor */
+	const u16 RcompResistor[3] = {121, 81, 100};
+	memcpy(rcomp_ptr, RcompResistor, sizeof(RcompResistor));
+}
+
+static void mainboard_fill_rcomp_strength_data(void *rcomp_strength_ptr) {
+	/* Rcomp target */
+	const u16 RcompTarget[5] = {100, 40, 20, 20, 26};
+	memcpy(rcomp_strength_ptr, RcompTarget, sizeof(RcompTarget));
+}
 
 void mainboard_memory_init_params(FSPM_UPD *mupd) {
 	FSP_M_CONFIG *mem_cfg;