Re: [EXT] Re: [PATCH v2] pmdomain: imx: Make IMX8M/IMX9 BLK_CTRL tristate

[Daniel Baluta]

On 4/14/26 04:59, Zhipeng Wang wrote:
>  > On 26-04-13, Zhipeng Wang wrote:
>>> Convert IMX8M_BLK_CTRL and IMX9_BLK_CTRL from bool to tristate to
>>> allow building as loadable modules.
>> Out of curiosity, why do you want to have a PM driver to be buildable as
>> module?
>>
>> Regards,
>>   Marco
>>
> Hi Marco,
>
> Thank you for your question.
>
> The primary motivation is to support Google's GKI (Generic Kernel Image)
> requirement for Android devices.
>
> GKI separates the kernel into two parts:
> 1. A unified kernel image (GKI) that is common across all Android devices
> 2. Vendor-specific drivers that must be built as loadable modules
>
> Under the GKI architecture, SoC-specific drivers like IMX8M/IMX9 BLK_CTRL
> cannot be built into the core kernel image. Instead, they must be loadable
> modules that vendors can ship separately. This allows:
>
> - A single kernel binary to support multiple hardware platforms
> - Vendors to update their drivers independently without rebuilding the entire kernel
> - Better compliance with Android's kernel update and security policies
>
Can you please add the below line in the commit message?
> For i.MX8M/i.MX9 devices running Android with GKI kernels, the BLK_CTRL
> drivers need to be loaded as modules during boot. Without tristate support,
> these devices cannot properly initialize their power domains, making them
> non-functional under GKI.