1 files changed, 38 insertions, 0 deletions
diff --git a/src/mainboard/asus/a88xm-e/bootblock.c b/src/mainboard/asus/a88xm-e/bootblock.c
new file mode 100644
index 0000000000..0bc8d2e15e
--- /dev/null
+++ b/src/mainboard/asus/a88xm-e/bootblock.c
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <amdblocks/acpimmio.h>
+#include <bootblock_common.h>
+#include <device/pnp_type.h>
+#include <superio/ite/common/ite.h>
+#include <superio/ite/it8728f/it8728f.h>
+
+static void sbxxx_enable_48mhzout(void)
+{
+	/* Set auxiliary output clock frequency on OSCOUT2 pin to be 48MHz */
+	u32 reg32;
+	reg32 = misc_read32(0x28);
+	reg32 &= ~(7 << 19);
+	reg32 |=  (2 << 19);
+	misc_write32(0x28, reg32);
+
+	/* Enable Auxiliary OSCOUT2 */
+	misc_write32(0x40, misc_read32(0x40) & ~(1 << 7));
+}
+
+static void superio_init_m(void)
+{
+	const pnp_devfn_t uart = PNP_DEV(0x2e, IT8728F_SP1);
+	const pnp_devfn_t gpio = PNP_DEV(0x2e, IT8728F_GPIO);
+
+	ite_kill_watchdog(gpio);
+	ite_enable_serial(uart, CONFIG_TTYS0_BASE);
+	ite_enable_3vsbsw(gpio);
+}
+
+void bootblock_mainboard_early_init(void)
+{
+	/* enable SIO clock */
+	sbxxx_enable_48mhzout();
+
+	superio_init_m();
+}