[PATCH v12 30/31] ARM: dts: add System MMU nodes of exynos5250

Doug Anderson dianders at chromium.org
Mon Apr 28 16:13:19 PDT 2014


Vikas,


On Sun, Apr 27, 2014 at 10:39 AM, Vikas Sajjan <sajjan.linux at gmail.com> wrote:
> Hi shaik,
>
> +Doug, Abhilash,
>
> On Sun, Apr 27, 2014 at 1:08 PM, Shaik Ameer Basha
> <shaik.ameer at samsung.com> wrote:
>> From: Cho KyongHo <pullip.cho at samsung.com>
>>
>> Signed-off-by: Cho KyongHo <pullip.cho at samsung.com>
>> ---
>>  arch/arm/boot/dts/exynos5250.dtsi |  270 ++++++++++++++++++++++++++++++++++++-
>>  1 file changed, 267 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/exynos5250.dtsi b/arch/arm/boot/dts/exynos5250.dtsi
>> index 3742331..eebd397 100644
>> --- a/arch/arm/boot/dts/exynos5250.dtsi
>> +++ b/arch/arm/boot/dts/exynos5250.dtsi
>> @@ -82,6 +82,16 @@
>>                 reg = <0x10044040 0x20>;
>>         };
>>
>> +       pd_isp: isp-power-domain at 0x10044020 {
>> +               compatible = "samsung,exynos4210-pd";
>> +               reg = <0x10044020 0x20>;
>> +       };
>> +
>> +       pd_disp1: disp1-power-domain at 0x100440A0 {
>> +               compatible = "samsung,exynos4210-pd";
>> +               reg = <0x100440A0 0x20>;
>> +       };
>> +
>
> As per subject "add System MMU nodes of exynos5250", it should only
> add SysMMU node.
> So, I think adding power domain nodes should go in a separate patch.
>
> Adding power domain nodes can break the system, if powering ON/OFF of
> the given power domain is NOT taken care well.
> I can see ISP is one such case. With this series I can see S2R breaks
> [1] on 5250 chromebook with current mainline kernel (same applies for
> arndale and smdk5250, but I have tested on these boards yet)

Thanks for catching that!  Let's make sure not to break suspend/resume.

Given that these power domains are actually used as the domains for
some of the System MMU nodes I don't totally object to adding them in
the same patch, but if they're breaking things then I agree that we
could leave them out and add them in a later patch (once issues are
sorted out).

-Doug



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