[meta-freescale] [PATCH 0/1] arm: imx: fsl_otp: make fuses (OTP memory) read-only

[Jon Nettleton]

Fair enough.  Can we all agree that it should default to disabled?

-Jon

On Fri, Nov 7, 2014 at 3:00 PM, Eric Bénard <eric at eukrea.com> wrote:
> Hi Alexander,
>
> Le Fri,  7 Nov 2014 10:43:34 +0100,
> Alexander Holler <holler at ahsoftware.de> a écrit :
>> Jon Nettleton made me aware that there is a driver which makes it very
>> easy to write to the OTP from userspace.
>>
>> And I have to admit that I was mildly shocked.
>>
>> Because OTP stands for One Time Programmable, it means the write
>> functionality of that driver can be used only once per HW and if that
>> is done wrong, the HW might be one of those famous electronic bricks
>> afterwards.
>>
>> So I've quickly written a patch which makes this driver to a friendly
>> citizen instead of an heavily armed cowboy.
>>
>> I really, really think this patch should be attached to all trees which
>> are including fsl_otp.c. It applies without any error to
>> imx_3.10.17_1.0.1_ga, imx_3.10.31_1.1.0_beta, linux-linaro-lsk-v3.14-mx6
>> and likely any other tree which includes that driver.
>>
> That's not shocking to have this feature in a reference design's BSP :
> Freescale provides base source code to evaluate their SOC and writing
> OTP is one feature of their SOC.
> Then that's the end product designer's responsibility to enable/disable
> features he wants or not on its product.
>
> The solution proposed by Otavio to add an option to ease the
> disabling of this feature is far better than fully removing the code.
>
> Best regards,
> Eric