1 files changed, 25 insertions, 0 deletions
diff --git a/src/mainboard/google/hatch/variants/mushu/ramstage.c b/src/mainboard/google/hatch/variants/mushu/ramstage.c
new file mode 100644
index 0000000000..5459f55cd1
--- /dev/null
+++ b/src/mainboard/google/hatch/variants/mushu/ramstage.c
@@ -0,0 +1,25 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2020 The coreboot project Authors.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <delay.h>
+#include <gpio.h>
+#include <baseboard/variants.h>
+#include <soc/gpio.h>
+
+void variant_ramstage_init(void)
+{
+	/*
+	 * Enable power to FPMCU, wait for power rail to stabilize,
+	 * and then deassert FPMCU reset.
+	 * Waiting for the power rail to stabilize can take a while,
+	 * a minimum of 400us on Kohaku.
+	 */
+	gpio_output(GPP_C11, 1);
+	mdelay(1);
+	gpio_output(GPP_A12, 1);
+}