Altera Nios II - Manual (Page 25)

© March 2014 Altera Corporation Nios II Flash Programmer User Guide
A. Non-Standard Flash Memories
This section covers advanced topics to support non-standard CFI flash memory. To
use the procedures in this section, you need the data sheet for the flash memory
device you are using. Make sure you fully understand the CFI aspects of the device.
Some CFI flash memory devices contain missing or incorrect CFI table information. In
such cases, the Nios II Flash Programmer might fail based on the erroneous
information in the CFI table. For these devices, the Nios II Flash Programmer
provides the following methods to override the CFI table and successfully program
flash memory:
■ Built-in recognition and override
■ Flash override files
■ Width mode override
Built-in Recognition and Override
The Nios II Flash Programmer contains code to recognize some devices with known
CFI table problems. On these devices, it overrides the incorrect table entries. Always
try using built-in recognition and override before trying to create an override file. To
determine whether the flash programmer recognizes the device, run the flash
programmer from the command line with the --debug option. If the flash
programmer overrides the CFI table, the flash programmer displays a message
"Override data for this device is built in".
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For details on using the flash programmer from the command line, refer to Chapter 3,
Using the Flash Programmer from the Command Line .
Flash Override Files
To support newly released flash memory devices which might have problems in the
CFI table, the Nios II Flash Programmer provides the ability to override CFI table
entries with flash override files. A flash override file lets you manually override
erroneous information in the CFI table, which enables the Nios II Flash Programmer
to function correctly.
Before creating an override file, run nios2-flash-programmer from the command line
with the --debug parameter, which lists the CFI table found in the device. Compare
the debug output with the device's data sheet.
Flash Override File Format
Flash override files contain two sections for each flash memory they override. The
first section declares the flash memory type. The second section is the CFI table
override data. The flash override file can contain comments preceded by a '#'
character.