4BA: Support for new direct-4BA instructions + W25Q256.V update

Large flash chips usually support special instructions to work with
4-bytes address directly from 3-bytes addressing mode and without
do switching to 4-bytes mode. There are 13h (4BA Read), 12h (4BA Program)
and 21h,5Ch,DCh (4BA Erase), correspondingly. However not all these
instructions are supported by all large flash chips. Some chips
support 13h only, some 13h,12h,21h and DCh, but not 5Ch. This depends
on the manufacturer of the chip.

This patch provides code to use direct 4-bytes addressing instructions.

This code should work but it tested partially only. My W25Q256FV has
support for 4BA_Read (13h), but doesn't have support 4BA_Program (12h)
and 4BA_Erase instructions. So, direct 4BA program and erase
should be tested after.

Patched files
-------------
chipdrivers.h
+ added functions declarations for spi4ba.c

flash.h
+ feature definitions added

flashchips.c
+ modified definition of Winbond W25Q256BV/W25Q256FV chips

flashrom.c
+ modified switch to 4-bytes addressing for direct-4BA instructions

spi4ba.h
+ definitions for 4-bytes addressing JEDEC commands
+ functions declarations from spi4ba.c (same as in chipdrivers.h, just to see)

spi4ba.c
+ functions for read/write/erase directly with 4-bytes address (from any mode)

Change-Id: Ib51bcc5de7826b30ad697fcbb9a5152bde2c2ac9
Signed-off-by: Boris Baykov <dev@borisbaykov.com>, Russia, Jan 2014
[clg: ported from
      https://www.flashrom.org/pipermail/flashrom/2015-January/013198.html ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-on: https://review.coreboot.org/20508
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/flashchips.c b/flashchips.c
index ca9a383..345ef88 100644
--- a/flashchips.c
+++ b/flashchips.c
@@ -14597,11 +14597,11 @@
 		/* supports SFDP */
 		/* OTP: 1024B total, 256B reserved; read 0x48; write 0x42, erase 0x44, read ID 0x4B */
 		/* FOUR_BYTE_ADDR: supports 4-bytes addressing mode */
-		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP | FEATURE_4BA_SUPPORT,
+		.feature_bits	= FEATURE_WRSR_WREN | FEATURE_OTP | FEATURE_4BA_SUPPORT | FEATURE_4BA_DIRECT_READ,
 		.four_bytes_addr_funcs =
 		{
 			.enter_4ba = spi_enter_4ba_b7_we, /* enter 4-bytes addressing mode by CMD B7 + WREN */
-			.read_nbyte = spi_nbyte_read_4ba, /* read from 4-bytes addressing mode */
+			.read_nbyte = spi_nbyte_read_4ba_direct, /* read directly from any mode, no need to enter 4ba */
 			.program_byte = spi_byte_program_4ba, /* write from 4-bytes addressing mode */
 			.program_nbyte = spi_nbyte_program_4ba /* write from 4-bytes addressing mode */
 		},