diff --git a/flash.h b/flash.h
index 56c0b4f..2219918 100644
--- a/flash.h
+++ b/flash.h
@@ -167,6 +167,14 @@
 	unsigned int page_size;
 	int feature_bits;
 
+	/* set of function pointers to use in 4-bytes addressing mode */
+	struct four_bytes_addr_funcs_set {
+		int (*enter_4ba) (struct flashctx *flash);
+		int (*read_nbyte) (struct flashctx *flash, unsigned int addr, uint8_t *bytes, unsigned int len);
+		int (*program_byte) (struct flashctx *flash, unsigned int addr, const uint8_t databyte);
+		int (*program_nbyte) (struct flashctx *flash, unsigned int addr, const uint8_t *bytes, unsigned int len);
+	} four_bytes_addr_funcs;
+
 	/* Indicate how well flashrom supports different operations of this flash chip. */
 	struct tested {
 		enum test_state probe;
diff --git a/flashrom.c b/flashrom.c
index c600efc..8e22434 100644
--- a/flashrom.c
+++ b/flashrom.c
@@ -2223,6 +2223,29 @@
 	if (flash->chip->unlock)
 		flash->chip->unlock(flash);
 
+	/* Switching to 4-Bytes Addressing mode if flash chip supports it */
+	if(flash->chip->feature_bits & FEATURE_4BA_SUPPORT) {
+		/* Do not switch if chip is already in 4-bytes addressing mode */
+		if (flash->chip->feature_bits & FEATURE_4BA_ONLY) {
+			msg_cdbg("Flash chip is already in 4-bytes addressing mode.\n");
+		}
+		/* Go to 4-Bytes Addressing mode */
+		else {
+			if (!flash->chip->four_bytes_addr_funcs.enter_4ba) {
+				msg_cerr("No function for Enter 4-bytes addressing mode for this flash chip.\n"
+					"Please report to flashrom@flashrom.org\n");
+				return 1;
+			}
+
+			if(flash->chip->four_bytes_addr_funcs.enter_4ba(flash)) {
+				msg_cerr("Switching to 4-bytes addressing mode failed!\n");
+				return 1;
+			}
+
+			msg_cdbg("Switched to 4-bytes addressing mode.\n");
+		}
+	}
+
 	return 0;
 }
 
diff --git a/spi.c b/spi.c
index 894f73f..0a4a618 100644
--- a/spi.c
+++ b/spi.c
@@ -110,7 +110,10 @@
 	 * means 0xffffff, the highest unsigned 24bit number.
 	 */
 	addrbase = spi_get_valid_read_addr(flash);
-	if (addrbase + flash->chip->total_size * 1024 > (1 << 24)) {
+	/* Show flash chip size warning if flash chip doesn't support
+	   4-Bytes Addressing mode and last address excedes 24 bits */
+	if (!(flash->chip->feature_bits & FEATURE_4BA_SUPPORT) &&
+	    addrbase + flash->chip->total_size * 1024 > (1 << 24)) {
 		msg_perr("Flash chip size exceeds the allowed access window. ");
 		msg_perr("Read will probably fail.\n");
 		/* Try to get the best alignment subject to constraints. */
diff --git a/spi25.c b/spi25.c
index 76242be..30b862f 100644
--- a/spi25.c
+++ b/spi25.c
@@ -28,6 +28,7 @@
 #include "chipdrivers.h"
 #include "programmer.h"
 #include "spi.h"
+#include "spi4ba.h"
 
 static int spi_rdid(struct flashctx *flash, unsigned char *readarr, int bytes)
 {
@@ -967,7 +968,10 @@
 		lenhere = min(start + len, (i + 1) * area_size) - starthere;
 		for (j = 0; j < lenhere; j += chunksize) {
 			toread = min(chunksize, lenhere - j);
-			rc = spi_nbyte_read(flash, starthere + j, buf + starthere - start + j, toread);
+			rc = (flash->chip->feature_bits & FEATURE_4BA_SUPPORT) == 0
+				? spi_nbyte_read(flash, starthere + j, buf + starthere - start + j, toread)
+				: flash->chip->four_bytes_addr_funcs.read_nbyte(flash, starthere + j,
+					buf + starthere - start + j, toread);
 			if (rc)
 				break;
 		}
@@ -1012,7 +1016,10 @@
 		lenhere = min(start + len, (i + 1) * page_size) - starthere;
 		for (j = 0; j < lenhere; j += chunksize) {
 			towrite = min(chunksize, lenhere - j);
-			rc = spi_nbyte_program(flash, starthere + j, buf + starthere - start + j, towrite);
+			rc = (flash->chip->feature_bits & FEATURE_4BA_SUPPORT) == 0
+				? spi_nbyte_program(flash, starthere + j, buf + starthere - start + j, towrite)
+				: flash->chip->four_bytes_addr_funcs.program_nbyte(flash, starthere + j,
+					buf + starthere - start + j, towrite);
 			if (rc)
 				break;
 			while (spi_read_status_register(flash) & SPI_SR_WIP)
@@ -1038,7 +1045,9 @@
 	int result = 0;
 
 	for (i = start; i < start + len; i++) {
-		result = spi_byte_program(flash, i, buf[i - start]);
+		result = (flash->chip->feature_bits & FEATURE_4BA_SUPPORT) == 0
+			? spi_byte_program(flash, i, buf[i - start])
+			: flash->chip->four_bytes_addr_funcs.program_byte(flash, i, buf[i - start]);
 		if (result)
 			return 1;
 		while (spi_read_status_register(flash) & SPI_SR_WIP)