Re: [PATCH] arm64: dts: exynos: correct GIC CPU interfaces address range on Exynos7

[Krzysztof Kozlowski]

On 05/08/2021 11:26, Alim Akhtar wrote:
> Hi Krzysztof,
> 
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
>> Sent: 05 August 2021 13:07
>> To: Rob Herring <robh+dt@xxxxxxxxxx>; devicetree@xxxxxxxxxxxxxxx; linux-
>> arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; linux-
>> kernel@xxxxxxxxxxxxxxx
>> Cc: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>; Chanwoo Choi
>> <cw00.choi@xxxxxxxxxxx>; Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>;
>> Sam Protsenko <semen.protsenko@xxxxxxxxxx>; Marc Zyngier
>> <maz@xxxxxxxxxx>
>> Subject: Re: [PATCH] arm64: dts: exynos: correct GIC CPU interfaces address
>> range on Exynos7
>>
>> On 05/08/2021 09:21, Krzysztof Kozlowski wrote:
>>> The GIC-400 CPU interfaces address range is defined as 0x2000-0x3FFF
>>> (by ARM).
>>>
>>
> Looking at DDI0471B_gic400_r0p1_trm.pdf, CPU interface range is 0x0000 ~ 0x10000
> 
>> I underestimated the issue - this is actually bug as there is a GICC_DIR
>> register at offset 0x1000. Therefore:
>>
> Looking at the exynos7 and exynos5433 UMs looks like GICC_DIR is at offset 0x2100 (from 0x1100_0000 GIC base)
> It is possible for you to cross check once?
> 

That's a mistake in Exynos manual. GICC_DIR is at 0x1000:
https://developer.arm.com/documentation/ddi0471/b/programmers-model/cpu-interface-register-summary

We have discussion here:
https://lore.kernel.org/linux-samsung-soc/0277c701-cc25-cdc5-d3b9-cf2cc2ba4de5@xxxxxxxxxxxxx/T/#m1ced9a28bed27f5cf74e281fb68efe1b57d5609e

Range of 0x10000 is definitely wrong as it overlaps with two other
ranges.


Best regards,
Krzysztof