Re: [PATCH v3 0/2] dmaengine: qcom: bam_dma: Add "powered remotely" mode for BAM-DMUX

From: Stephan Gerhold <stephan@gerhold.net>
To: Bhupesh Sharma <bhupesh.sharma@linaro.org>
Cc: Vinod Koul <vkoul@kernel.org>,
	Bjorn Andersson <bjorn.andersson@linaro.org>,
	Andy Gross <agross@kernel.org>, Rob Herring <robh+dt@kernel.org>,
	MSM <linux-arm-msm@vger.kernel.org>,
	dmaengine@vger.kernel.org,
	devicetree <devicetree@vger.kernel.org>,
	~postmarketos/upstreaming@lists.sr.ht
Subject: Re: [PATCH v3 0/2] dmaengine: qcom: bam_dma: Add "powered remotely" mode for BAM-DMUX
Date: Thu, 28 Oct 2021 09:15:14 +0200	[thread overview]
Message-ID: <YXpOAlTO80A4tZcT@gerhold.net> (raw)
In-Reply-To: <CAH=2NtzfTqkwZum3owipC0kHvX2BMRssqRFmFAXPFkXK_SmN1w@mail.gmail.com>

Hi Bhupesh,

On Thu, Oct 28, 2021 at 12:20:35PM +0530, Bhupesh Sharma wrote:
> On Mon, 25 Oct 2021 at 11:47, Stephan Gerhold <stephan@gerhold.net> wrote:
> >
> > On Mon, Oct 25, 2021 at 11:18:08AM +0530, Vinod Koul wrote:
> > > On 18-10-21, 12:24, Stephan Gerhold wrote:
> > > > The BAM Data Multiplexer (BAM-DMUX) provides access to the network data
> > > > channels of modems integrated into many older Qualcomm SoCs, e.g.
> > > > Qualcomm MSM8916 or MSM8974.
> > > >
> > > > Shortly said, BAM-DMUX is built using a simple protocol layer on top of
> > > > a DMA engine (Qualcomm BAM DMA). For BAM-DMUX, the BAM DMA engine runs in
> > > > a special mode where the modem/remote side is responsible for powering
> > > > on the BAM when needed but we are responsible to initialize it.
> > > > The BAM is powered off when unneeded by coordinating power control
> > > > via bidirectional interrupts from the BAM-DMUX driver.
> > > >
> > > > This series adds one possible solution for handling the "powered remotely"
> > > > mode in the bam_dma driver.
> > >
> > > This looks good me me. Bhupesh/Stephan what was the conclusion on the
> > > the discussion you folks had?
> > >
> >
> > Basically I said I would wait if you still want to take this for 5.16. :)
> > There is a conflict with the DT schema conversion in Bhupesh's series,
> > but it's trivial to solve no matter which of the patches is applied first.
> >
> > Since Bhupesh still needs to send v5 as far as I can tell (and has a
> > much larger series overall), I think it's fine to apply this one first.
> >
> > Bhupesh, you can just copy-paste this below qcom,controlled-remotely
> > in your DT schema if Vinod applies this patch first:
> >
> >   qcom,powered-remotely:
> >     $ref: /schemas/types.yaml#/definitions/flag
> >     description:
> >       Indicates that the bam is powered up by a remote processor
> >       but must be initialized by the local processor.
> 
> Sure, I can respin my v5 with 'qcom,powered-remotely' property added,
> if this series gets applied first.

Thanks!

> Can I add you S-o-B to the same?

I literally just copy-pasted this from "qcom,controlled-remotely" in
your patch with the description from my dt-bindings change that already
has my S-o-B. I don't think it is necessary to add my S-o-B to your
patch as well just for this. :)

Thanks,
Stephan