[PATCH v4 7/8] ARM: dts: Exynos5422: fix OPP tables

Javier Martinez Canillas javier at osg.samsung.com
Tue Dec 8 05:41:57 PST 2015


Hello Krzysztof,

On 12/08/2015 05:13 AM, Krzysztof Kozlowski wrote:
> On 08.12.2015 03:18, Bartlomiej Zolnierkiewicz wrote:
>> From: Ben Gamari <ben at smart-cactus.org>
>>
>> The Exynos 5422 is identical to the 5800 except for the fact that it
>> boots from the A7 cores. Consequently, the core numbering is different:
>> cores 0-3 are A7s whereas 4-7 are A15s.
>>
>> We can reuse the device tree of the 5800 for the 5422 but we must take
>> care to override the OPP tables and CPU clocks.  These are otherwise
>> inherited from the exynos5800 devicetree, which has the CPU clusters
>> reversed compared to the 5422. This results in the A15 cores only
>> reaching 1.4GHz, the maximum rate of the KFC clock.
>>
>> Cc: Javier Martinez Canillas <javier at osg.samsung.com>
>> Signed-off-by: Ben Gamari <ben at smart-cactus.org>
>> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie at samsung.com>
>> ---
>>  arch/arm/boot/dts/exynos5422-cpus.dtsi | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
> 
> This looks like a very-non-atomic way of handling a change. You added
> opp tables to exynos5420 before so at that time they will be applied to
> Odroid XU3 family which uses different CPU order. After that you are
> fixing the tables to proper CPU order. Direct bisectability probably
> won't be an issue because all of DTS would go to separate branch... but
> the logic behind confuses.
> 

Agreed.

> I think this should be squashed into 3/8.
> 

I think the patch should be split in two changes, the CPUs device nodes
having the wrong clock for clusters is a bug and has to be fixed in a
patch before adding the OPP tables and the OPP tables changes should be
separated and merged with patch 3/8 as you suggest.

> Best regards,
> Krzysztof
> 

Best regards,
-- 
Javier Martinez Canillas
Open Source Group
Samsung Research America



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