diff --git a/spi4ba.c b/spi4ba.c
new file mode 100644
index 0000000..72df874
--- /dev/null
+++ b/spi4ba.c
@@ -0,0 +1,327 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2014 Boris Baykov
+ *
+ * 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
+ */
+
+/*
+ * SPI chip driver functions for 4-bytes addressing
+ */
+
+#include <string.h>
+#include "flash.h"
+#include "chipdrivers.h"
+#include "spi.h"
+#include "programmer.h"
+#include "spi4ba.h"
+
+/* #define MSG_TRACE_4BA_FUNCS 1 */
+
+#ifdef MSG_TRACE_4BA_FUNCS
+#define msg_trace(...) print(MSG_DEBUG, __VA_ARGS__)
+#else
+#define msg_trace(...)
+#endif
+
+/* Enter 4-bytes addressing mode (without sending WREN before) */
+int spi_enter_4ba_b7(struct flashctx *flash)
+{
+	const unsigned char cmd[JEDEC_ENTER_4_BYTE_ADDR_MODE_OUTSIZE] = { JEDEC_ENTER_4_BYTE_ADDR_MODE };
+
+	msg_trace("-> %s\n", __func__);
+
+	/* Switch to 4-bytes addressing mode  */
+	return spi_send_command(flash, sizeof(cmd), 0, cmd, NULL);
+}
+
+/* Enter 4-bytes addressing mode with sending WREN before */
+int spi_enter_4ba_b7_we(struct flashctx *flash)
+{
+	int result;
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= JEDEC_ENTER_4_BYTE_ADDR_MODE_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_ENTER_4_BYTE_ADDR_MODE },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s\n", __func__);
+
+	/* Switch to 4-bytes addressing mode  */
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution\n", __func__);
+	}
+	return result;
+}
+
+/* Program one flash byte from 4-bytes addressing mode */
+int spi_byte_program_4ba(struct flashctx *flash, unsigned int addr,
+				 uint8_t databyte)
+{
+	int result;
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= JEDEC_BYTE_PROGRAM_OUTSIZE + 1,
+		.writearr	= (const unsigned char[]){
+					JEDEC_BYTE_PROGRAM,
+					(addr >> 24) & 0xff,
+					(addr >> 16) & 0xff,
+					(addr >> 8) & 0xff,
+					(addr & 0xff),
+					databyte
+				},
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s (0x%08X)\n", __func__, addr);
+
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution at address 0x%x\n",
+			__func__, addr);
+	}
+	return result;
+}
+
+/* Program flash bytes from 4-bytes addressing mode */
+int spi_nbyte_program_4ba(struct flashctx *flash, unsigned int addr,
+			  const uint8_t *bytes, unsigned int len)
+{
+	int result;
+	unsigned char cmd[(JEDEC_BYTE_PROGRAM_OUTSIZE + 1) - 1 + 256] = {
+		JEDEC_BYTE_PROGRAM,
+		(addr >> 24) & 0xff,
+		(addr >> 16) & 0xff,
+		(addr >> 8) & 0xff,
+		(addr >> 0) & 0xff
+	};
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= (JEDEC_BYTE_PROGRAM_OUTSIZE + 1) - 1 + len,
+		.writearr	= cmd,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s (0x%08X-0x%08X)\n", __func__, addr, addr + len - 1);
+
+	if (!len) {
+		msg_cerr("%s called for zero-length write\n", __func__);
+		return 1;
+	}
+	if (len > 256) {
+		msg_cerr("%s called for too long a write\n", __func__);
+		return 1;
+	}
+
+	memcpy(&cmd[(JEDEC_BYTE_PROGRAM_OUTSIZE + 1) - 1], bytes, len);
+
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution at address 0x%x\n",
+			__func__, addr);
+	}
+	return result;
+}
+
+/* Read flash bytes from 4-bytes addressing mode */
+int spi_nbyte_read_4ba(struct flashctx *flash, unsigned int addr,
+		   uint8_t *bytes, unsigned int len)
+{
+	const unsigned char cmd[JEDEC_READ_OUTSIZE + 1] = {
+		JEDEC_READ,
+		(addr >> 24) & 0xff,
+		(addr >> 16) & 0xff,
+		(addr >> 8) & 0xff,
+		(addr >> 0) & 0xff
+	};
+
+	msg_trace("-> %s (0x%08X-0x%08X)\n", __func__, addr, addr + len - 1);
+
+	/* Send Read */
+	return spi_send_command(flash, sizeof(cmd), len, cmd, bytes);
+}
+
+/* Erases 4 KB of flash from 4-bytes addressing mode */
+int spi_block_erase_20_4ba(struct flashctx *flash, unsigned int addr,
+		       unsigned int blocklen)
+{
+	int result;
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= JEDEC_SE_OUTSIZE + 1,
+		.writearr	= (const unsigned char[]){
+					JEDEC_SE,
+					(addr >> 24) & 0xff,
+					(addr >> 16) & 0xff,
+					(addr >> 8) & 0xff,
+					(addr & 0xff)
+				},
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s (0x%08X-0x%08X)\n", __func__, addr, addr + blocklen - 1);
+
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution at address 0x%x\n",
+			__func__, addr);
+		return result;
+	}
+	/* Wait until the Write-In-Progress bit is cleared.
+	 * This usually takes 15-800 ms, so wait in 10 ms steps.
+	 */
+	while (spi_read_status_register(flash) & SPI_SR_WIP)
+		programmer_delay(10 * 1000);
+	/* FIXME: Check the status register for errors. */
+	return 0;
+}
+
+/* Erases 32 KB of flash from 4-bytes addressing mode */
+int spi_block_erase_52_4ba(struct flashctx *flash, unsigned int addr,
+		       unsigned int blocklen)
+{
+	int result;
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= JEDEC_BE_52_OUTSIZE + 1,
+		.writearr	= (const unsigned char[]){
+					JEDEC_BE_52,
+					(addr >> 24) & 0xff,
+					(addr >> 16) & 0xff,
+					(addr >> 8) & 0xff,
+					(addr & 0xff)
+				},
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s (0x%08X-0x%08X)\n", __func__, addr, addr + blocklen - 1);
+
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution at address 0x%x\n",
+			__func__, addr);
+		return result;
+	}
+	/* Wait until the Write-In-Progress bit is cleared.
+	 * This usually takes 100-4000 ms, so wait in 100 ms steps.
+	 */
+	while (spi_read_status_register(flash) & SPI_SR_WIP)
+		programmer_delay(100 * 1000);
+	/* FIXME: Check the status register for errors. */
+	return 0;
+}
+
+/* Erases 64 KB of flash from 4-bytes addressing mode */
+int spi_block_erase_d8_4ba(struct flashctx *flash, unsigned int addr,
+		       unsigned int blocklen)
+{
+	int result;
+	struct spi_command cmds[] = {
+	{
+		.writecnt	= JEDEC_WREN_OUTSIZE,
+		.writearr	= (const unsigned char[]){ JEDEC_WREN },
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= JEDEC_BE_D8_OUTSIZE + 1,
+		.writearr	= (const unsigned char[]){
+					JEDEC_BE_D8,
+					(addr >> 24) & 0xff,
+					(addr >> 16) & 0xff,
+					(addr >> 8) & 0xff,
+					(addr & 0xff)
+				},
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}, {
+		.writecnt	= 0,
+		.writearr	= NULL,
+		.readcnt	= 0,
+		.readarr	= NULL,
+	}};
+
+	msg_trace("-> %s (0x%08X-0x%08X)\n", __func__, addr, addr + blocklen - 1);
+
+	result = spi_send_multicommand(flash, cmds);
+	if (result) {
+		msg_cerr("%s failed during command execution at address 0x%x\n",
+			__func__, addr);
+		return result;
+	}
+	/* Wait until the Write-In-Progress bit is cleared.
+	 * This usually takes 100-4000 ms, so wait in 100 ms steps.
+	 */
+	while (spi_read_status_register(flash) & SPI_SR_WIP)
+		programmer_delay(100 * 1000);
+	/* FIXME: Check the status register for errors. */
+	return 0;
+}