4BA: Flashrom integration for the 4-bytes addressing extensions

This patch integrates code of the previous patch into Flashrom's code.
All the integrations is around 3 functions spi_nbyte_read, spi_nbyte_program
and spi_byte_program. After this patch then are not static and can be called
by their pointers saved in flashchips array. Also I added to flashrom.c some
code to switch a chip to 4-bytes addressing mode. And one error message is
corrected in spi.c because it's not suitable for 32-bit addresses.

Patched files
-------------
flash.h
+ added set of 4-bytes address functions to flashchip structure definition

flashrom.c
+ added switch to 4-bytes addressing more for chips which support it

serprog.c
+ added 4-bytes addressing spi_nbyte_read call to serprog_spi_read

spi.c
+ fixed flash chip size check in spi_chip_read

spi25.c
+ added 4-bytes addressing spi_nbyte_read call to spi_read_chunked
+ added 4-bytes addressing spi_nbyte_program call to spi_write_chunked
+ added 4-bytes addressing spi_byte_program call to spi_chip_write_1

Conflicts:
	serprog.c

Change-Id: Ib051cfc93bd4aa7580519e0e6206d025f3ca8049
Signed-off-by: Boris Baykov <dev@borisbaykov.com>, Russia, Jan 2014
[clg: ported from
      https://www.flashrom.org/pipermail/flashrom/2015-January/013205.html ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-on: https://review.coreboot.org/20505
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
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. */