Re: [PATCH v9 4/4] PCI: dwc: Support ECAM mechanism by enabling iATU 'CFG Shift Feature'

[ALOK TIWARI]

On 9/9/2025 12:37 PM, Manivannan Sadhasivam wrote:
> Currently, the driver is not making use of this CFG shift feature, thereby
> creating the iATU outbound map for each config access to the devices,
> causing latency and wasting CPU cycles.
>
> So to avoid this, configure the controller to enable CFG shift feature by
> enabling the 'CFG Shift' bit of the 'iATU Control 2 Register'.
>
> As a result of enabling CFG shift (ECAM), there is longer a need to map the
> DBI register space separately as the DBI region falls under the 'config'
> space used for ECAM (as DBI is used to access the Root Port).

nit : there is no longer a need

Thanks,
Alok