Writing to the OCOTP on mx28 boards

[Sascha Hauer]

On Fri, Sep 28, 2012 at 02:23:32PM +0200, Maxime Ripard wrote:
> Le 28/09/2012 14:08, Maxime Ripard a écrit :
> > Hi everyone,
> > 
> > I'm trying to write down some data to the /dev/ocotp file, which is
> > basically a one time programming chip containing four bytes.
> > 
> > Using the command mw -b -d /dev/ocotp 0-3 0x01020304 writes down only
> > "4" to the first byte of the OCOTP, which is not quite what I was
> > expecting. What's the correct syntax for the mw command?
> 
> Ok, just found out, it should be
> mw -l -d /dev/ocotp 0-3 0x01020304

Not quite. 0-3 is wrong, though appearantly happens to work. It should
be:

mw -d /dev/ocotp 0 0x01020304

(-l can be skipped, as 32bit accesses are default). If you want to write
multiple words you can do a:

mw -d /dev/ocotp 0 0xdeadbeef 0x12345678 0x11223344

The 0-3 notation is only for 'md'

Sascha


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