On some flash chips data with addresses more than 24-bit field
can address may be accessed by using Extended Address Register.
The register has 1-byte size and stores high byte of 32-bit address.
Then flash can be read from 3-bytes addressing mode with writing
high byte of address to this Register. By using this way we have
access to full memory of a chip. Some chips may support this method
only.
This patch provides code use Extended Address Register.
Patched files
-------------
chipdrivers.h
+ added functions declarations for spi4ba.c
flash.h
+ feature definitions added
flashrom.c
+ modified switch to 4-bytes addressing to support extended address register
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 write Extended Address Register
+ functions for read/write/erase with Extended Address Register
Change-Id: I09a8aa11de2ca14901f142c67c83c4fa0def4e27
Signed-off-by: Boris Baykov <dev@borisbaykov.com>, Russia, Jan 2014
[clg: ported from
https://www.flashrom.org/pipermail/flashrom/2015-January/013200.html ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-on: https://review.coreboot.org/20507
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
If flash chip is switched to 4-bytes addressing mode then all
read/erase/program instructions will be switched from 3-bytes mode
to 4-bytes mode. Then well known instructions like 03h (Read),
02h (Program) and 20h,52h,D8h (Erase) will become one byte longer
and accept 4-bytes address instead of 3-bytes.
This patch provides support for well known instructions in 4-bytes
addressing mode. Also here is the code to enter 4-bytes addressing
mode by execute the instruction B7h (Enter 4-bytes mode).
Patched files
-------------
chipdrivers.h
+ added functions declarations for spi4ba.c
flash.h
+ feature definitions added
Makefile
+ added spi4ba.c
Added files
-----------
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 enter 4-bytes addressing mode
+ functions for read/write/erase in 4-bytes addressing mode
Change-Id: Ie72e2a89cd75fb4d09f48e81c4c1d927c317b7a7
Signed-off-by: Boris Baykov <dev@borisbaykov.com>, Russia, Jan 2014
[clg: ported from
https://www.flashrom.org/pipermail/flashrom/2015-January/013199.html ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-on: https://review.coreboot.org/20513
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
