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

-----Original Message-----
From: Krzysztof Kozlowski <redacted>
Sent: 05 August 2021 15:15
To: Alim Akhtar <alim.akhtar@samsung.com>; 'Rob Herring'
[off-list ref]; devicetree@vger.kernel.org; linux-arm-
kernel@lists.infradead.org; linux-samsung-soc@vger.kernel.org; linux-
kernel@vger.kernel.org
Cc: 'Chanwoo Choi' <cw00.choi@samsung.com>; 'Pankaj Dubey'
[off-list ref]; 'Sam Protsenko'
[off-list ref]; 'Marc Zyngier' [off-list ref]
Subject: Re: [PATCH] arm64: dts: exynos: correct GIC CPU interfaces address
range on Exynos7

On 05/08/2021 11:43, Krzysztof Kozlowski wrote:

quoted

On 05/08/2021 11:26, Alim Akhtar wrote:

quoted

Hi Krzysztof,

quoted

-----Original Message-----
From: Krzysztof Kozlowski <redacted>
Sent: 05 August 2021 13:07
To: Rob Herring <robh+dt@kernel.org>; devicetree@vger.kernel.org;
linux- arm-kernel@lists.infradead.org;
linux-samsung-soc@vger.kernel.org; linux- kernel@vger.kernel.org
Cc: Alim Akhtar <alim.akhtar@samsung.com>; Chanwoo Choi
[off-list ref]; Pankaj Dubey

[off-list ref];

quoted

quoted

quoted

Sam Protsenko [off-list ref]; Marc Zyngier
[off-list ref]
Subject: Re: [PATCH] arm64: dts: exynos: correct GIC CPU interfaces
address range on Exynos7

On 05/08/2021 09:21, Krzysztof Kozlowski wrote:

quoted

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

quoted

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?

quoted

quoted

That's a mistake in Exynos manual. GICC_DIR is at 0x1000:

0x1000 from CPU base offset, so 0x3000 from GIC base.

quoted

https://developer.arm.com/documentation/ddi0471/b/programmers-

model/cp

quoted

u-interface-register-summary

We have discussion here:
https://lore.kernel.org/linux-samsung-soc/0277c701-cc25-cdc5-d3b9-cf2c

c2ba4de5@canonical.com/T/#m1ced9a28bed27f5cf74e281fb68efe1b57d5609
e

Thanks for pointing to this discussion, I missed this.
Agreed.
Feel Free to add
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>

quoted

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

Best regards,
Krzysztof