[PATCH v2 1/2] PCI/ASPM: Override the ASPM and Clock PM states set by BIOS for devicetree platforms

Jon Hunter jonathanh at nvidia.com
Mon Feb 16 06:03:41 PST 2026


Hi Mani, Krishna,

On 23/01/2026 13:56, Manivannan Sadhasivam wrote:

...

> So to properly fix it, we need the controller drivers to perform below checks
> for all devices under the Root bus(ses) before initiating D3Cold:
> 
> 1. Check if the device state is D3Hot. If it is not D3Hot, then the device is
> expected to stay in the current D-state by the client driver, so D3Cold should
> not be initiated.
> 
> 2. Check if the device is wakeup capable. If it is, then check if it can support
> wakeup from D3Cold (with WAKE#).
> 
> Only if both conditions are satisfied for all the devices under the Root busses,
> then the host controller driver should initiate D3Cold sequence.
> 
> Krishna is going to post a patch that performs the above checks for
> pcie-designware-host driver. But since the above checks are platform agnostic,
> we should introduce a helper and resuse it across other controllers as well.


Do you have a rough idea of when you will be posting patches for this?

Thanks
Jon

-- 
nvpublic




More information about the Linux-nvme mailing list