From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout1.samsung.com (mailout1.samsung.com [203.254.224.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 844BB293C44 for ; Tue, 5 Aug 2025 17:19:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.254.224.24 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754414401; cv=none; b=YgiQ9iDtzXMzxneJEnanMeRLQg5tfE4XztA6OoMrJJ8j32oG2YnX1X2ruGSAYbt1YqSsEC3ZDVaiNRwnA/uxQSf3l6qJLhMhTUvGmgXx28cBpmq8iTPHMdvdtcWxjN+I12+Qvb1zfTXC2TpYFMUNH9KaADIuc4RZdRqGoWvX2gA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754414401; c=relaxed/simple; bh=wXk7AXwYUilCzs6h7m2OKQQRTWnaTbHCa5F4w44YHJ8=; h=From:To:Cc:In-Reply-To:Subject:Date:Message-ID:MIME-Version: Content-Type:References; b=CWImKbH+U3TEavnMZWoJAnwswQmzgavJzdYZgsRqM/4E2XnDAVATxL7g4rfL+8vLJsSbTcvAf1I136fn8KNZJT8tTDJKpVA2VEBqrAIQ+D+tUboPuNPBVNl2zi9qDWmVP+qM8CeIi5fX4WKiUpmRJ2AOpXdhGReLQ5Yjn9dGqIk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=bTJ+Ll8i; arc=none smtp.client-ip=203.254.224.24 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="bTJ+Ll8i" Received: from epcas5p3.samsung.com (unknown [182.195.41.41]) by mailout1.samsung.com (KnoxPortal) with ESMTP id 20250805171951epoutp01849b84529302db33fee9ee4038f5ad75~Y7pgXwi0U2141321413epoutp01I for ; Tue, 5 Aug 2025 17:19:51 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.samsung.com 20250805171951epoutp01849b84529302db33fee9ee4038f5ad75~Y7pgXwi0U2141321413epoutp01I DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1754414391; bh=wXk7AXwYUilCzs6h7m2OKQQRTWnaTbHCa5F4w44YHJ8=; h=From:To:Cc:In-Reply-To:Subject:Date:References:From; b=bTJ+Ll8iCG5gbMfodw4A8Fwup93QAVqCdqc7W6ZJyTjSDDuZyJ0W3tvib2U5NQRZP x35RMlkFSXMWCS+DvqkB68ojlK8YQPBVlZ2ldf/oiFR2sKjijeasHTxtIyaZQui/1N YWkDDDGv+QsMlR8zZNRu/kXYyN1n0O6G+nbZdxmQ= Received: from epsnrtp03.localdomain (unknown [182.195.42.155]) by epcas5p4.samsung.com (KnoxPortal) with ESMTPS id 20250805171950epcas5p42b2fd0f1f2586a9b20f77a611c78d496~Y7pfTi66b0183001830epcas5p4U; Tue, 5 Aug 2025 17:19:50 +0000 (GMT) Received: from epcas5p1.samsung.com (unknown [182.195.38.87]) by epsnrtp03.localdomain (Postfix) with ESMTP id 4bxKtG0H8Gz3hhT3; Tue, 5 Aug 2025 17:19:50 +0000 (GMT) Received: from epsmtip1.samsung.com (unknown [182.195.34.30]) by epcas5p3.samsung.com (KnoxPortal) with ESMTPA id 20250805171949epcas5p30c43bd9ea6a12814fad1be7988dc2bc7~Y7pd5c16_1679116791epcas5p3H; Tue, 5 Aug 2025 17:19:49 +0000 (GMT) Received: from INBRO002756 (unknown [107.122.3.168]) by epsmtip1.samsung.com (KnoxPortal) with ESMTPA id 20250805171946epsmtip13608ef786b01f6568760f2030e4f31e3~Y7pbsftBi1987919879epsmtip13; Tue, 5 Aug 2025 17:19:46 +0000 (GMT) From: "Alim Akhtar" To: "'Konrad Dybcio'" , "'Manivannan Sadhasivam'" Cc: "'Krzysztof Kozlowski'" , "'Ram Kumar Dwivedi'" , , , , , , , , , , , , , , In-Reply-To: Subject: RE: [PATCH 2/3] arm64: dts: qcom: sa8155: Add gear and rate limit properties to UFS Date: Tue, 5 Aug 2025 22:49:45 +0530 Message-ID: <061b01dc062d$25c47800$714d6800$@samsung.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Mailer: Microsoft Outlook 16.0 Content-Language: en-us Thread-Index: AQEsDrE8JRCAsHRairxCtqkF8AWYdgJ3dE0KAYiFM6ICWTmtcAIeLXciAcYGcMYCPwKykwJqyOxTAqeW3QQBLCbdjgHWPm1htQ+xfrA= X-CMS-MailID: 20250805171949epcas5p30c43bd9ea6a12814fad1be7988dc2bc7 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" CMS-TYPE: 105P cpgsPolicy: CPGSC10-542,Y X-CFilter-Loop: Reflected X-CMS-RootMailID: 20250805170638epcas5p4cb0cc78c5b5d77072cec547380b9f03d References: <20250722161103.3938-1-quic_rdwivedi@quicinc.com> <20250722161103.3938-3-quic_rdwivedi@quicinc.com> <2a3c8867-7745-4f0a-8618-0f0f1bea1d14@kernel.org> <1701ec08-21bc-45b8-90bc-1cd64401abd8@kernel.org> <2nm7xurqgzrnffustrsmswy2rbug6geadaho42qlb7tr2jirlr@uw5gaery445y> <11ea828a-6d35-4ac6-a207-0284870c28fc@oss.qualcomm.com> > -----Original Message----- > From: Konrad Dybcio > Sent: Tuesday, August 5, 2025 10:36 PM > To: Manivannan Sadhasivam > Cc: Krzysztof Kozlowski ; Ram Kumar Dwivedi > ; alim.akhtar=40samsung.com; > avri.altman=40wdc.com; bvanassche=40acm.org; robh=40kernel.org; > krzk+dt=40kernel.org; conor+dt=40kernel.org; andersson=40kernel.org; > konradybcio=40kernel.org; James.Bottomley=40hansenpartnership.com; > martin.petersen=40oracle.com; agross=40kernel.org; linux-arm- > msm=40vger.kernel.org; linux-scsi=40vger.kernel.org; > devicetree=40vger.kernel.org; linux-kernel=40vger.kernel.org > Subject: Re: =5BPATCH 2/3=5D arm64: dts: qcom: sa8155: Add gear and rate = limit > properties to UFS >=20 > On 8/5/25 6:55 PM, Manivannan Sadhasivam wrote: > > On Tue, Aug 05, 2025 at 03:16:33PM GMT, Konrad Dybcio wrote: > >> On 8/1/25 2:19 PM, Manivannan Sadhasivam wrote: > >>> On Fri, Aug 01, 2025 at 11:12:42AM GMT, Krzysztof Kozlowski wrote: > >>>> On 01/08/2025 11:10, Ram Kumar Dwivedi wrote: > >>>>> > >>>>> > >>>>> On 01-Aug-25 1:58 PM, Manivannan Sadhasivam wrote: > >>>>>> On Thu, Jul 24, 2025 at 09:48:53AM GMT, Krzysztof Kozlowski wrote: > >>>>>>> On 22/07/2025 18:11, Ram Kumar Dwivedi wrote: > >>>>>>>> Add optional limit-hs-gear and limit-rate properties to the UFS > >>>>>>>> node to support automotive use cases that require limiting the > >>>>>>>> maximum Tx/Rx HS gear and rate due to hardware constraints. > >>>>>>> > >>>>>>> What hardware constraints? This needs to be clearly documented. > >>>>>>> > >>>>>> > >>>>>> Ram, both Krzysztof and I asked this question, but you never > >>>>>> bothered to reply, but keep on responding to other comments. This > >>>>>> won't help you to get this series merged in any form. > >>>>>> > >>>>>> Please address *all* review comments before posting next iteration= . > >>>>> > >>>>> Hi Mani, > >>>>> > >>>>> Apologies for the delay in responding. > >>>>> I had planned to explain the hardware constraints in the next > patchset=E2=80=99s=20commit=20message,=20which=20is=20why=20I=20didn=E2= =80=99t=20reply=20earlier.=0D=0A>=20>>>>>=0D=0A>=20>>>>>=20To=20clarify:=20= the=20limitations=20are=20due=20to=20customer=20board=20designs,=20not=20ou= r=0D=0A>=20SoC.=20Some=20boards=20can't=20support=20higher=20gear=20operati= on,=20hence=20the=20need=20for=0D=0A>=20optional=20limit-hs-gear=20and=20li= mit-rate=20properties.=0D=0A>=20>>>>>=0D=0A>=20>>>>=0D=0A>=20>>>>=20That's= =20vague=20and=20does=20not=20justify=20the=20property.=20You=20need=20to= =0D=0A>=20>>>>=20document=20instead=20hardware=20capabilities=20or=20charac= teristic.=20Or=0D=0A>=20>>>>=20explain=20why=20they=20cannot.=20With=20such= =20form=20I=20will=20object=20to=20your=20next=0D=0A>=20patch.=0D=0A>=20>>>= >=0D=0A>=20>>>=0D=0A>=20>>>=20I=20had=20an=20offline=20chat=20with=20Ram=20= and=20got=20clarified=20on=20what=20these=20properties=0D=0A>=20are.=0D=0A>= =20>>>=20The=20problem=20here=20is=20not=20with=20the=20SoC,=20but=20with= =20the=20board=20design.=20On=0D=0A>=20>>>=20some=20Qcom=20customer=20desig= ns,=20both=20the=20UFS=20controller=20in=20the=20SoC=20and=0D=0A>=20>>>=20t= he=20UFS=20device=20are=20capable=20of=20operating=20at=20higher=20gears=20= (say=20G5).=0D=0A>=20>>>=20But=20due=20to=20board=20constraints=20like=20po= or=20thermal=20dissipation,=20routing=0D=0A>=20>>>=20loss,=20the=20board=20= cannot=20efficiently=20operate=20at=20the=20higher=20speeds.=0D=0A>=20>>>= =0D=0A>=20>>>=20So=20the=20customers=20wanted=20a=20way=20to=20limit=20the= =20gear=20speed=20(say=20G3)=20and=0D=0A>=20>>>=20rate=20(say=20Mode-A)=20o= n=20the=20specific=20board=20DTS.=0D=0A>=20>>=0D=0A>=20>>=20I'm=20not=20nec= essarily=20saying=20no,=20but=20have=20you=20explored=20sysfs=20for=20this?= =0D=0A>=20>>=0D=0A>=20>>=20I=20suppose=20it=20may=20be=20too=20late=20(if= =20the=20driver=20would=20e.g.=20init=20the=20UFS=0D=0A>=20>>=20at=20max=20= gear/rate=20at=20probe=20time,=20it=20could=20cause=20havoc=20as=20it=20tri= es=20to=0D=0A>=20>>=20load=20the=20userland)..=0D=0A>=20>>=0D=0A>=20>=0D=0A= >=20>=20If=20the=20driver=20tries=20to=20run=20with=20unsupported=20max=20g= ear=20speed/mode,=20it=0D=0A>=20>=20will=20just=20crash=20with=20the=20erro= r=20spit.=0D=0A>=20=0D=0A>=20OK=0D=0A>=20=0D=0A>=20just=20a=20couple=20rela= ted=20nits=20that=20I=20won't=20bother=20splitting=20into=20separate=20emai= ls=0D=0A>=20=0D=0A>=20rate=20(mode?=20I'm=20seeing=20both=20names)=20should= =20probably=20have=20dt-bindings=0D=0A>=20defines=20while=20gear=20doesn't= =20have=20to=20since=20they're=20called=20G=20anyway,=0D=0A>=20with= =20the=20bindings=20description=20strongly=20discouraging=20use,=20unless= =20absolutely=0D=0A>=20necessary=20(e.g.=20in=20the=20situation=20we=20have= =20right=20there)=0D=0A>=20=0D=0A>=20I'd=20also=20assume=20the=20code=20sho= uld=20be=20moved=20into=20the=20ufs-common=20code,=20rather=0D=0A>=20than= =20making=20it=20ufs-qcom=20specific=0D=0A>=20=0D=0A>=20Konrad=0D=0ASince= =20this=20is=20a=20board=20specific=20constrains=20and=20not=20a=20SoC=20pr= operties,=20have=20an=20option=20of=20handling=20this=20via=20bootloader=20= is=20explored?=0D=0AOr=20passing=20such=20properties=20via=20bootargs=20and= =20handle=20the=20same=20in=20the=20driver?=0D=0A=0D=0A