[U-Boot] [PATCH 1/1] arm: mx5: Add fuse supply gate enable in fsl_iim

[Benoît Thébaudeau]

Dear Sergey Alyoshin,

On Thursday, December 12, 2013 5:46:21 PM, Sergey Alyoshin wrote:
> Enable fuse supply gate before fuse programming and disable after.
> 
> Signed-off-by: Sergey Alyoshin <alyoshin.s at gmail.com>
> Tested-by: Sergey Alyoshin <alyoshin.s at gmail.com>

Have you also tested without this patch first too? On which SoC?

My tests had shown that this is not required on i.MX51. It's probably the same
on i.MX53. I have not checked if i.MX25 and i.MX35 also have such a bit, but
they also work fine as is. This is not even done by Freescale:
http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/char/mxc_iim.c?h=imx_3.0.35_4.1.0

In the Reference Manual, nothing says in the IIM / fuse chapters that this bit
is needed for proper programming. It is just described in the CCM register map,
and nothing refers to it. It is perhaps only useful for test purposes. I'd vote
for letting this bit untouched if possible.

Fabio, do you have more information from Freescale about this bit?

Best regards,
Benoît