Re: [PATCH 5/5] bus: mhi: host: Remove redundant dma_wmb() before ctx wp update

[Hemant Kumar]

On 5/2/2022 3:41 AM, Manivannan Sadhasivam wrote:
> The endpoint device will only read the context wp when the host rings
> the doorbell. And moreover the doorbell write is using writel(). This
> guarantess that the prior writes will be completed before ringing
> doorbell.
>
> So there is no need of an additional dma_wmb() to order the coherent
> memory writes w.r.t each other. Even if the writes gets reordered, it
> won't affect the endpoint device.
>
> Cc: Loic Poulain <loic.poulain@xxxxxxxxxx>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> Reviewed by: Hemant Kumar <quic_hemantk@xxxxxxxxxxx>