diff --git a/src/southbridge/amd/agesa/hudson/sd.c b/src/southbridge/amd/agesa/hudson/sd.c
new file mode 100644
index 0000000..941bb97
--- /dev/null
+++ b/src/southbridge/amd/agesa/hudson/sd.c
@@ -0,0 +1,69 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 Sage Electronic Engineering, LLC
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <device/device.h>
+#include <delay.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <device/pci_ops.h>
+#include <arch/io.h>
+#include "hudson.h"
+
+static void sd_init(struct device *dev)
+{
+	u32 stepping;
+
+	stepping = pci_read_config32(dev_find_slot(0, PCI_DEVFN(0x18, 3)), 0xFC);
+
+	struct southbridge_amd_agesa_hudson_config *sd_chip =
+		(struct southbridge_amd_agesa_hudson_config *)(dev->chip_info);
+
+	if (sd_chip->sd_mode == 3) {	/* SD 3.0 mode */
+		pci_write_config32(dev, 0xA4, 0x31FEC8B2);
+		pci_write_config32(dev, 0xA8, 0x00002503);
+		pci_write_config32(dev, 0xB0, 0x02180C19);
+		pci_write_config32(dev, 0xD0, 0x0000078B);
+	}
+	else {				/* SD 2.0 mode */
+		if ((stepping & 0x0000000F) == 0) {	/* Stepping A0 */
+			pci_write_config32(dev, 0xA4, 0x31DE32B2);
+			pci_write_config32(dev, 0xB0, 0x01180C19);
+			pci_write_config32(dev, 0xD0, 0x0000058B);
+		}
+		else {					/* Stepping >= A1 */
+			pci_write_config32(dev, 0xA4, 0x31FE3FB2);
+			pci_write_config32(dev, 0xB0, 0x01180C19);
+			pci_write_config32(dev, 0xD0, 0x0000078B);
+		}
+	}
+}
+
+static struct device_operations sd_ops = {
+	.read_resources = pci_dev_read_resources,
+	.set_resources = pci_dev_set_resources,
+	.enable_resources = pci_dev_enable_resources,
+	.init = sd_init,
+	.scan_bus = 0,
+};
+
+static const struct pci_driver sd_driver __pci_driver = {
+	.ops = &sd_ops,
+	.vendor = PCI_VENDOR_ID_AMD,
+	.device = PCI_DEVICE_ID_AMD_YANGTZE_SD,
+};