RE: [PATCH v2 1/2] interconnect: qcom: sdx75: Drop QPIC interconnect and BCM nodes

["Lakshmi Sowjanya D (QUIC)" <quic_laksd@quicinc.com>]

> -----Original Message-----
> From: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
> Sent: Friday, September 26, 2025 7:17 PM
> To: manivannan.sadhasivam@oss.qualcomm.com; Georgi Djakov
> <djakov@kernel.org>; Rohit Agarwal <quic_rohiagar@quicinc.com>; Konrad
> Dybcio <konradybcio@kernel.org>; Rob Herring <robh@kernel.org>; Krzysztof
> Kozlowski <krzk+dt@kernel.org>; Conor Dooley <conor+dt@kernel.org>
> Cc: linux-arm-msm@vger.kernel.org; linux-pm@vger.kernel.org; linux-
> kernel@vger.kernel.org; Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org>; devicetree@vger.kernel.org; Manivannan
> Sadhasivam <mani@kernel.org>; Raviteja Laggyshetty (QUIC)
> <quic_rlaggysh@quicinc.com>; Lakshmi Sowjanya D (QUIC)
> <quic_laksd@quicinc.com>; stable@vger.kernel.org
> Subject: Re: [PATCH v2 1/2] interconnect: qcom: sdx75: Drop QPIC
> interconnect and BCM nodes
> 
> On 9/26/25 8:42 AM, Manivannan Sadhasivam via B4 Relay wrote:
> > From: Raviteja Laggyshetty <quic_rlaggysh@quicinc.com>
> >
> > As like other SDX SoCs, SDX75 SoC's QPIC BCM resource was modeled as a
> > RPMh clock in clk-rpmh driver. However, for SDX75, this resource was
> > also described as an interconnect and BCM node mistakenly. It is
> > incorrect to describe the same resource in two different providers, as
> > it will lead to votes from clients overriding each other.
> >
> > Hence, drop the QPIC interconnect and BCM nodes and let the clients
> > use clk-rpmh driver to vote for this resource.
> >
> > Without this change, the NAND driver fails to probe on SDX75, as the
> > interconnect sync state disables the QPIC nodes as there were no
> > clients voting for this ICC resource. However, the NAND driver had
> > already voted for this BCM resource through the clk-rpmh driver. Since
> > both votes come from Linux, RPMh was unable to distinguish between
> > these two and ends up disabling the QPIC resource during sync state.
> >
> > Cc: stable@vger.kernel.org
> > Fixes: 3642b4e5cbfe ("interconnect: qcom: Add SDX75 interconnect
> > provider driver")
> > Signed-off-by: Raviteja Laggyshetty <quic_rlaggysh@quicinc.com>
> > [mani: dropped the reference to bcm_qp0, reworded description]
> > Signed-off-by: Manivannan Sadhasivam
> > <manivannan.sadhasivam@oss.qualcomm.com>
> > ---
> 
> Too bad no one noticed for the 2 years the platform has been upstream..
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
> 
> Konrad

Tested-by: Lakshmi Sowjanya D <quic_laksd@quicinc.com>  # on SDX75

Regards,
Lakshmi Sowjanya D