[Arm-netbook] defining the eoma68 eeprom usage

[Christopher Havel]

On 11/4/2013 3:35 PM, Arokux X wrote:
> On Mon, Nov 4, 2013 at 9:30 PM, Christopher Thomas
> <christopher at firemothindustries.com> wrote:
>>
>>
>> On Mon, Nov 4, 2013 at 2:05 PM, joem <joem at martindale-electric.co.uk> wrote:
>>> : yes.  my concerns here are that the EEPROM would be overwritten by
>>> :user applications otherwise, potentially destroying the ability of CPU
>>> :Cards to identify the device.
>>>
>>> I2C eeproms dirt cheap - have two eeproms - one user data (such as
>>> calibration data
>>> for instruments, keys, etc) and one for system data.
>>>
>>> _______________________________________________
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>>
>> Given the need for device-tree info, and RID, etc etc, presumably, how large
>> of an EEPROM would we technically need?
> Device Tree eats this much:
>
> user$ du -h arch/arm/boot/dts/*.dtb | grep sun
> 12K    arch/arm/boot/dts/sun4i-a10-a1000.dtb
> 12K    arch/arm/boot/dts/sun4i-a10-cubieboard.dtb
> 12K    arch/arm/boot/dts/sun4i-a10-hackberry.dtb
> 12K    arch/arm/boot/dts/sun4i-a10-mini-xplus.dtb
> 8.0K    arch/arm/boot/dts/sun5i-a10s-olinuxino-micro.dtb
> 8.0K    arch/arm/boot/dts/sun5i-a13-olinuxino.dtb
> 8.0K    arch/arm/boot/dts/sun6i-a31-colombus.dtb
> 12K    arch/arm/boot/dts/sun7i-a20-cubieboard2.dtb
> 12K    arch/arm/boot/dts/sun7i-a20-cubietruck.dtb
> 12K    arch/arm/boot/dts/sun7i-a20-olinuxino-micro.dtb
>
>
>
>> The Most recent revision MEBs have a 64K EEPROM, perhaps we could split the
>> single eeprom memory into two segments?
>>
>> --
>> Christopher Thomas
>> Firemoth Industries, LLC - Owner
>> christopher at firemothindustries.com
>> 214-458-5990
>>
>> _______________________________________________
>> arm-netbook mailing list arm-netbook at lists.phcomp.co.uk
>> http://lists.phcomp.co.uk/mailman/listinfo/arm-netbook
>> Send large attachments to arm-netbook at files.phcomp.co.uk
> _______________________________________________
> arm-netbook mailing list arm-netbook at lists.phcomp.co.uk
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> Send large attachments to arm-netbook at files.phcomp.co.uk
...that's 108k.

Also, I like the idea that IIRC Luke had -- two EEPROMs, one writable by 
the OS (for userspace or config data) and one not (for device data). 
Unbrickability is a definite virtue :D