[U-Boot] ti, am3517: errata 430973 workaround

[Jeroen Hofstee]

Hello Robert, Andreas,

On 09-12-14 22:45, Robert Nelson wrote:
> On Mon, Dec 8, 2014 at 4:19 PM, Jeroen Hofstee <jeroen at myspectrum.nl> wrote:
>> Hi,
>>
>> A while ago [1], a RFC was posted to disable workaround for
>> besides others, errata 430973. It is a bit unclear to me which
>> revision actually need this workaround, but as suggested in
>> [2] also enabling this workaround in Linux seem to make some
>> weird problems go away in linux (signal 4, bad instruction,
>> 11 segfaults etc).
>>
>> As said, I am a bit in doubt why this works. The board in question
>> is a tam3517 derived one:
>>
>> cat /proc/cpuinfo
>> Processor    : ARMv7 Processor rev 7 (v7l)
>> BogoMIPS    : 397.57
>> Features    : swp half thumb fastmult vfp edsp neon vfpv3 tls
>> CPU implementer    : 0x41
>> CPU architecture: 7
>> CPU variant    : 0x1
>> CPU part    : 0xc08
>> CPU revision    : 7
>>
>> Which makes this a r1p7 I assume, and hence the workaround
>> of linux, CONFIG_ARM_ERRATA_430973, "This option enables the
>> workaround for the 430973 Cortex-A8 (r1p0..r1p2) erratum",
>> should not be needed it seems.
> Digging thru my old beagle notes 430973 is also needed for "r1p3"
> (dm3730/bb-xm), so that config option was never updated since the
> errata was first discovered in r1p2 devices..
>
> Fixed in r2p1 sounds about right, as i know for sure it works fine in
> 'r3p2' (am335x/bbb)

Thanks for the clarification. I sent a patch to the linux folks
to update the help text.

Regards,
Jeroen