[PATCH v2 4/5] arm: mach-k3: j721e-init.c: J7200: Add support for CONFIG_K3_OPP_LOW

[Aniket Limaye]

On 30/10/24 13:58, Manorit Chawdhry wrote:
> Hi Neha, Aniket,
> 
> On 13:31-20241030, Manorit Chawdhry wrote:
>> Hi Aniket,
>>
>> On 15:40-20241029, Manorit Chawdhry wrote:
>>> Hi Aniket,
>>>
>>> On 18:27-20241023, Aniket Limaye wrote:
>>>> From: Reid Tonking <reidt at ti.com>
>>>>
>>>> The default j7200 devicetree and k3_avs driver set 2GHz/1GHz frequency
>>>> for A72/MSMC clks and the OPP_NOM voltage.
>>>>
>>>> J7200 SOCs may support OPP_LOW Operating Performance Point:
>>>> 1GHz/500MHz clks for A72/MSMC and OPP_LOW AVS voltage read from efuse.
>>>>
>>>> Hence, add a config check to select OPP_LOW specs:
>>>> - Check if OPP_LOW AVS voltage read from efuse is valid.
>>>> - Update the clock frequencies in devicetree.
>>>> - Program the OPP_LOW AVS voltage for VDD_CPU.
>>>>
>>>> Signed-off-by: Reid Tonking <reidt at ti.com>
>>>> Signed-off-by: Aniket Limaye <a-limaye at ti.com>
>>>>
>>>> ---
> [...]
>>>>   
>>>> +int fix_freq(const void *fdt)
>>
>> I think this can be static as well btw, maybe rename it to something
>> more descriptive as well. fdt_fixup_a72_clock_frequency?
> 
> Do you think ft_system_setup is a good place for doing this fixup btw?
> Was wondering that it would be good to know what all DT fixups are being
> done at some common place instead of multiple scattered places but not
> sure when does ft_system_setup kick in, would it be before we startup
> a72?


So it looks like ft_system_setup is being called only before booting 
into linux Kernel.

As discussed offline, another place to handle fdt_fixups cleanly could 
be spl_perform_fixups() in board/ti/j721e/evm.c

I would agree that this dt fixup would be better placed there instead of 
in board_init_f() directly. Will try doing that.

Thanks,
Aniket

> 
> Regards,
> Manorit