Date:   Thu, 9 Dec 2021 08:00:22 -0800
From:   Bjorn Andersson <bjorn.andersson@linaro.org>
To:     Rajendra Nayak <quic_rjendra@quicinc.com>
Cc:     agross@kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org, swboyd@chromium.org, mka@chromium.org
Subject: Re: [PATCH v2 2/3] soc: qcom: rpmhpd: Remove mx/cx relationship on
 sc7280
Message-ID: <YbIoFjh9QbdsPnQh@ripper>
References: <1638871712-18636-1-git-send-email-quic_rjendra@quicinc.com>
 <1638871712-18636-3-git-send-email-quic_rjendra@quicinc.com>
 <YbEYyGHqaHGeRXsV@builder.lan>
 <7e9f6cbe-17c9-53ff-95a8-2f2bbdeb1d23@quicinc.com>
 <7b8f359f-de8d-4ace-d28d-8242683e1f8c@quicinc.com>
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On Thu 09 Dec 07:37 PST 2021, Rajendra Nayak wrote:

> 
> On 12/9/2021 12:29 PM, Rajendra Nayak wrote:
> > 
> > On 12/9/2021 2:12 AM, Bjorn Andersson wrote:
> > > On Tue 07 Dec 04:08 CST 2021, Rajendra Nayak wrote:
> > > 
> > > > While the requirement to specify the active + sleep and active-only MX
> > > > power-domains as the parents of the corresponding CX power domains is
> > > > applicable for most SoCs, we have some like the sc7280 where this
> > > > dependency is not applicable.
> > > > Define new rpmhpd structs for cx and cx_ao without the mx as
> > > > parent and use them for sc7280.
> > > > 
> > > > Signed-off-by: Rajendra Nayak <quic_rjendra@quicinc.com>
> > > > ---
> > > > ? drivers/soc/qcom/rpmhpd.c | 18 ++++++++++++++++--
> > > > ? 1 file changed, 16 insertions(+), 2 deletions(-)
> > > > 
> > > > diff --git a/drivers/soc/qcom/rpmhpd.c b/drivers/soc/qcom/rpmhpd.c
> > > > index c71481d..4599efe 100644
> > > > --- a/drivers/soc/qcom/rpmhpd.c
> > > > +++ b/drivers/soc/qcom/rpmhpd.c
> > > > @@ -120,6 +120,20 @@ static struct rpmhpd cx_ao = {
> > > > ????? .res_name = "cx.lvl",
> > > > ? };
> > > > +static struct rpmhpd cx_ao_no_parent;
> > > > +static struct rpmhpd cx_no_parent = {
> > > 
> > > There are multiple variations of how each of these can be parented, but
> > > only one way they can be without a parent. So how about we turn this the
> > > other way around?
> > > 
> > > I.e. let's name this one "cx" and the existing one "cx_w_mx_parent".
> > > 
> > > 
> > > This will be particularly useful when you look at mmcx, which on
> > > 8150/8180 has mx as parent and on 8450 has cx as parent.
> 
> I noticed mmcx on 8150/8180 does not have mx as parent, nevertheless
> I went ahead and moved to the _w_<parent-name>_parent suffix because
> it made sense if we did run into a situation like this in the future.
> 

You're correct, the 8150/8180 mmcx are wrong, let's fix that once your
patches has settled (probably later today).

Thanks for cleaning up the driver!

Regards,
Bjorn

> > > 
> > > 
> > > PS. Unfortunately I had merged 8450 since you wrote this series, I tried
> > > to just fix it up as I applied your patch, but noticed 8450_cx and
> > > 8450_mmcx and wanted to get your opinion on this first.
> > 
> > I agree that sounds like a reasonable thing to do, I hadn't looked at 8450
> > so did not notice it, I will rebase my patches on top and repost.
> > 
> > > 
> > > Regards,
> > > Bjorn
> > > 
> > > > +??? .pd = { .name = "cx", },
> > > > +??? .peer = &cx_ao_no_parent,
> > > > +??? .res_name = "cx.lvl",
> > > > +};
> > > > +
> > > > +static struct rpmhpd cx_ao_no_parent = {
> > > > +??? .pd = { .name = "cx_ao", },
> > > > +??? .active_only = true,
> > > > +??? .peer = &cx_no_parent,
> > > > +??? .res_name = "cx.lvl",
> > > > +};
> > > > +
> > > > ? static struct rpmhpd mmcx_ao;
> > > > ? static struct rpmhpd mmcx = {
> > > > ????? .pd = { .name = "mmcx", },
> > > > @@ -273,8 +287,8 @@ static const struct rpmhpd_desc sc7180_desc = {
> > > > ? /* SC7280 RPMH powerdomains */
> > > > ? static struct rpmhpd *sc7280_rpmhpds[] = {
> > > > -??? [SC7280_CX] = &cx,
> > > > -??? [SC7280_CX_AO] = &cx_ao,
> > > > +??? [SC7280_CX] = &cx_no_parent,
> > > > +??? [SC7280_CX_AO] = &cx_ao_no_parent,
> > > > ????? [SC7280_EBI] = &ebi,
> > > > ????? [SC7280_GFX] = &gfx,
> > > > ????? [SC7280_MX] = &mx,
> > > > -- 
> > > > 2.7.4
> > > >