[PATCH] arch: arm: mach-imx: document field return in CSF template

[Bastian Krause]

On 2/25/22 11:25, Marc Kleine-Budde wrote:
> On 25.02.2022 11:03:44, Bastian Krause wrote:
>> Activating the field return configuration returns a locked-down board
>> (nearly) to its open state. In order to burn the FIELD_RETURN fuse, the
>> CSF must contain a specific unlock command with the device's UID.
>>
>> Signed-off-by: Bastian Krause <bst at pengutronix.de>
>> ---
>>   .../include/mach/habv4-imx6-gencsf-template.h        | 12 ++++++++++++
>>   1 file changed, 12 insertions(+)
>>
>> diff --git a/arch/arm/mach-imx/include/mach/habv4-imx6-gencsf-template.h b/arch/arm/mach-imx/include/mach/habv4-imx6-gencsf-template.h
>> index a60b485292..45da2981cb 100644
>> --- a/arch/arm/mach-imx/include/mach/habv4-imx6-gencsf-template.h
>> +++ b/arch/arm/mach-imx/include/mach/habv4-imx6-gencsf-template.h
>> @@ -39,6 +39,18 @@ hab Engine = SETUP_HABV4_ENGINE
>>   hab Features = SETUP_HABV4_FEATURES
>>   #endif
>>   
>> +/*
>> +// allow fusing FIELD_RETURN
>> +// # ocotp0.permanent_write_enable=1
>> +// # mw -l -d /dev/imx-ocotp 0xb8 0x1
>> +hab [Unlock]
>> +hab Engine = OCOTP
>> +hab Features = FIELD RETURN
>> +// device-specific UID:
>> +// $ dd if=/sys/bus/nvmem/devices/imx-ocotp0/nvmem bs=4 skip=1 count=2 status=none | hexdump -ve '1/1 "0x%.2x, "' | sed 's/, $//'
>> +hab UID = 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08
> 
> You probably want to comment this all out in the template...

I don't get it, that's all inside the /* commented section */.

Bastian

> 
>> +*/
>> +
>>   hab [Install Key]
>>   /* verification key index in key store (0, 2...4) */
>>   hab Verification index = 0
>> -- 
>> 2.30.2
>>
>>

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