From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 6796416A956 for ; Mon, 20 Jul 2026 14:12:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784556725; cv=none; b=nT2gSCizsZ66kfpc0rPCHHczILIwX7UsDFB3DlrpNoaimcyEExNWj6C/7EYyRGUgbP4WEBSyfoan9JGzHrcr0T5VbWXf6J5ITSXqFARK9xVf07AlPpxYWhnPSkfnvwMqPVZD+gALHL7Y7CIjSZc0Bgdi4b4c1DbJNsWlB9LMO5I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784556725; c=relaxed/simple; bh=CrusvQrBASBFhooN+pfdEkfPmD79gBrBLgltXL1IqQA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ef9nDiRkX/YmKOQHO48hHLZIoh3FZMt0tq1MGhE3yHADUWDDtHHa0tWXDvQIaiGe4PO2jDS2WhS/WYsqrx0aFwSek0FY50qKNQ5VPq8tszo5CKq8JYRsvVATkc6nzOQkECQtNBDRkKuEmYpVfne3EkGnQU/0p9xz5c911WqLs38= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=MgerdfAG; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=e192sQQD; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="MgerdfAG"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="e192sQQD" Received: from pps.filterd (m0279867.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 66KDrQid3860613 for ; Mon, 20 Jul 2026 14:12:03 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= IFbXZVYlpWFB+86AR3x1jH6JDJM2yKuesn95gcq6Bt8=; b=MgerdfAGT8P4AsIY Bb7+lF6ar+WGa3Xv8UPRLAtbfgAI/6Ay7vu4wY8upS/JK5Sa4OIcHGWZO/LmPp0k PADPqEm1K7t+R5eprqmKKggHeDeSa53LKG2MLyxAs0/FUqGMOCsuYtxn4FkbrXzI zmiICvyIcNsfmP6ZlurHvwAOL4qtRJobKmZRaS1f9yLlpu3CrZpcasDVXaIiCTfK 6EfQNPZFVKokSQ7lcV9W5Ok46nfJaXR7ADHgw4qM5OmhoYwIx6FuzhrK1raFem3J TzKdTl6gu/FyBHhh2CR6PO9dZ+0Rf9UkFaBg3yU2yHJLFjoNkvwdwYnB2VZlm/3Z R3ul/Q== Received: from mail-oi1-f199.google.com (mail-oi1-f199.google.com [209.85.167.199]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4fhfpg1p2f-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Mon, 20 Jul 2026 14:12:03 +0000 (GMT) Received: by mail-oi1-f199.google.com with SMTP id 5614622812f47-4a441e90050so5470518b6e.1 for ; Mon, 20 Jul 2026 07:12:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1784556723; x=1785161523; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=IFbXZVYlpWFB+86AR3x1jH6JDJM2yKuesn95gcq6Bt8=; b=e192sQQDN6GSnhBCh/cPWbDoy1Ff0dYKyqHIFubOlrVbxxpdOMLBC0aoPQ2KuMp8NH G3S0iHxdZUw8ewrR49JWfB4Za1XgZyTHqfpxCc3K4PYeYroBdIFagajbq2UJLIWHHXgh A1wxPhkHr3iuOZ0vSQe8k/uIXz7PQOWL/qK0pGOH8znk4O6tYBMDr+rRS9O8ekVEKX9x BygJQQZZgHqVZtYy3vcUWmM1kcK0/Tx3ieBG9Fuv5+TiKmeMD7QTq8BaaazoFNi7Tyoa EZges0kJKozN7px3+BYlFtTA3tig5Jvi1UDTMbPyO27dOC+l7Ve+k+3Rz5jPOaIF/qlc PWiA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784556723; x=1785161523; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=IFbXZVYlpWFB+86AR3x1jH6JDJM2yKuesn95gcq6Bt8=; b=DsynYE2g/o3WgT0Snd/YEF5WA9wW/IMc1+zo6svOD1G/ge2tVI1tGc7ujtBv3dPfJn dk0Gv46P2LeHAgDpIxwbNg/Wia9dd6+xzTtBSXuYCasZorvi272kftbcNwcqaAlcujaP McSnjY6dGOQck8R7KuMZgChgHgX7RkldYKsa0JCo5VR8Pp/Chvv0ymun1/yNXeCtKU0h fj1vk5++CHsG7gy6fwia3DL5BUgcrgKkH8KYa0zqLb3o/xm0RKQAl2Tz9TaMG4ttdzA0 Nor2KOMrsznZDYktJB01i6SZvCVwsFY1ch1Ip0clO6xpA7IojxhA/GFq71m6rejhzODP BWqg== X-Forwarded-Encrypted: i=1; AHgh+Rr6hIXkgNSS3+fxIkQ0PBfHJ5aj2h8jGamcW4Aq+7pE6KItdqjpW425gVNKZm4SNkJutfRx99vW2laFP8Y=@vger.kernel.org X-Gm-Message-State: AOJu0Yy7I55sQOhvyoPCpr3oKWt+ukB/q3+gN/OVRp/+u20R3nXWUxc7 46aruDhc7qDodXgUmrIvNiDgVRUDBnsNA9DelNcIggz7Oob53qRTx5g8yJC3yef6j4H24jtejg9 lzO2gOC3mdpiuhWUE5tBBgIa1sjaYyBAErDcjk4eXGntmV5Kngvi8LxfaCVoJ2bvAuQ8= X-Gm-Gg: AfdE7ckCZfgmNNPHZ32dB/xKnS1mopYCzINpaynCvnMv4Nlx3a96RMRZZvW9Vb2z8z7 dBND4sg7Rbz/+z2M0JvnvY5h7n3xwWTWRtq+IR7oOicR3XJTrCD22Wl27aGMrX3SSRHuFVc+w52 ih1Jayv4YwJvLqkPxouSUp4vrk+ntleXiM/0jcTJnBnYnulYE49/8iOcHc1IfIOMzW9HcWP5pa+ F1xeSlfghcU+egerIlJ8aXzYewCPnNtQlK9REx1XyL/NNJ7MIjMXC+uvSfP7pAbKzRcyZutK71U PMHlPfpsrzjvVj/IGMqPF7XZZy7Wg4ealw8U/O6d/Rr2Xb4H+P64OwSc3R7Bmj6OoOyTowetKW5 WNGxx2QFR0tj35BrIPOYY/qT3bQLB X-Received: by 2002:a05:6808:c3cb:b0:495:fa67:7496 with SMTP id 5614622812f47-4a4cf26bb93mr7248849b6e.14.1784556722667; Mon, 20 Jul 2026 07:12:02 -0700 (PDT) X-Received: by 2002:a05:6808:c3cb:b0:495:fa67:7496 with SMTP id 5614622812f47-4a4cf26bb93mr7248832b6e.14.1784556722182; Mon, 20 Jul 2026 07:12:02 -0700 (PDT) Received: from [10.218.33.224] ([202.46.22.19]) by smtp.gmail.com with ESMTPSA id 5614622812f47-4a4d3d36340sm7497247b6e.16.2026.07.20.07.11.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 20 Jul 2026 07:12:01 -0700 (PDT) Message-ID: <9f31bf3d-3c7d-45ba-bc25-e6349f689b70@oss.qualcomm.com> Date: Mon, 20 Jul 2026 19:41:35 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/6] dt-bindings: iommu: arm,smmu: Document interconnects property To: Bjorn Andersson Cc: Dmitry Baryshkov , Will Deacon , Robin Murphy , Joerg Roedel , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Konrad Dybcio , Rob Clark , linux-arm-kernel@lists.infradead.org, iommu@lists.linux.dev, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Krzysztof Kozlowski References: <20260706-smmu_interconnect_addition-v3-0-afdca0125a65@oss.qualcomm.com> <20260706-smmu_interconnect_addition-v3-1-afdca0125a65@oss.qualcomm.com> <4e266d45-ee88-42f8-91da-6253927686ae@oss.qualcomm.com> Content-Language: en-US From: Bibek Kumar Patro In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Proofpoint-Spam-Info: AW1haW4tMjYwNzIwMDE1OCBTYWx0ZWRfX1DV1IU/NGe35 +kTC6mybXhBVEczshZu95b22w7yVmSobY6pH8k+uFmJMrr+Gs5FW4B1Ere2BD/4LxybGniGi7ml YYY83WgrogvkO4eFWns6rT7y3Ta9N1Q= X-Proofpoint-GUID: hvg3a1bj31tOqmK9x2P2oTvHfiTDVIou X-Proofpoint-ORIG-GUID: hvg3a1bj31tOqmK9x2P2oTvHfiTDVIou X-Authority-Analysis: v=2.4 cv=c+6bhx9l c=1 sm=1 tr=0 ts=6a5e2cb3 cx=c_pps a=yymyAM/LQ7lj/HqAiIiKTw==:117 a=fChuTYTh2wq5r3m49p7fHw==:17 a=IkcTkHD0fZMA:10 a=RAioF0-LDSMA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=eoimf2acIAo5FJnRuUoq:22 a=EUspDBNiAAAA:8 a=fPhLyPd3YuFPpQYp6doA:9 a=QEXdDO2ut3YA:10 a=efpaJB4zofY2dbm2aIRb:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzIwMDE1OCBTYWx0ZWRfX/BJ2/kxbbCJ+ h4ylQ1c22shGmE+2iH20gxNxX7ZF4wyiW8pTx7loeQLm+VHbFwOSeKpZsgsMrTPcyPinTlLJt3+ jzIdTT2SQg5CF+HTDg7Yiik0OHgPObFFqcxPDGgNY0teYVdHKNjxtN7uO1O0fjn9SO1woEnwBPN UZHDMC1dgzxN/xNWcJFMmvvNMyOD6vrEa+CCsW/uO1mGuyP0svueT37Mdi/mwr3WrzXtOImi1O4 7m3lUZ9SzC9NOdyjISK4tGzTMpgv/zXSmn0rGqI7yJ7GKssn1gqdqx9KpnyCFSLjEmevxo079Ff 5wsrA9YrxAebW92bREALcRJh+FZpuAh09X0CV/WyjTYueKvo/ksNMjWtzhAUlv2OR4YtMBf+/mZ GvBXZXjPckvfJjGDifEHTNLosKoAJujIZ/duzh+68IfwKVT9duKp43iLMIP9rntoYezpxhah7l8 vd+i3BC7GPYDGGi9idQ== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-20_03,2026-07-20_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 adultscore=0 suspectscore=0 bulkscore=0 priorityscore=1501 malwarescore=0 impostorscore=0 phishscore=0 clxscore=1015 lowpriorityscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607200158 On 7/8/2026 8:48 PM, Bjorn Andersson wrote: > On Wed, Jul 08, 2026 at 08:22:00PM +0530, Bibek Kumar Patro wrote: >> >> >> On 7/7/2026 10:12 PM, Dmitry Baryshkov wrote: >>> On Tue, Jul 07, 2026 at 06:06:59PM +0530, Bibek Kumar Patro wrote: >>>> >>>> >>>> On 7/6/2026 11:09 PM, Dmitry Baryshkov wrote: >>>>> On Mon, Jul 06, 2026 at 10:26:34PM +0530, Bibek Kumar Patro wrote: >>>>>> Some SoC implementations require a bandwidth vote on an interconnect >>>>>> path before the SMMU register space is accessible. Add the optional >>>>> >>>>> Why is it limited only to those SoCs? Is it also applicable to other >>>>> Qualcomm SoCs? >>>>> >>>> >>>> I was hoping to keep this series focused on the core infrastructure >>>> changes: the bindings, base ICC bandwidth-voting support, and DT >>>> interconnect properties for the platforms currently supported on >>>> Qualcomm Linux and have been validated so far. >>>> >>>> The additional targets have not been tested yet, so I'd prefer >>>> to add their support in a separate follow-up series once validation >>>> is complete, rather than growing this series further. WDYT? >>> >>> Then it should be a part of the commit message. All SoCs since SDM12345 >>> need to vote on the interconnect (and then, in the cover letter mention >>> that you convert only a few of the SoCs). We possibly can help with >>> testing on other platforms. >>> >> >> Ack, sounds reasonable. >> I'll add the first platform onwards which interconnect voting is required in >> commit description. > > But to what degree is this related to a specific set of platforms? If we > look ahead, aren't we expecting the list to grow to include all > platforms in the end - resulting in a lot of noise and churn. > We have seen this issue consistently on SM8750 and later platforms, along with at least one customer-reported instance on SM8550. As a result, downstream Android implementations already vote for the required interconnect bandwidth explicitly on these platforms. On Qualcomm Linux targets, we have observed similar issues on Kodiak, with a few occurrences on Talos as well. My understanding is that the interconnects property remains optional, but in practice it is needed for Adreno SMMU operation on these platforms. > Can you give an example of a platform where there is no interconnect > path to vote for here or where it would be harmful to do so? > I do not anticipate any functional issues or side effects from explicitly voting for the interconnect on Qualcomm platforms where the path exists. >> And update the cover letter to clarify that this series adds >> support for the Qualcomm Linux-supported targets available today, and >> the list will be expanded in follow-up series as additional platforms >> are enabled. >> > > The binding should not reflect what has been implemented and verified in > Linux, it defines the contract between DeviceTree and the OS. > Since the property is optional, would it be necessary to add in AllOf the list of compatible for which the property hasn't been added yet, or for the compatibles where it is added? Thanks & regards, Bibek > Regards, > Bjorn > >> Thanks & regards, >> Bibek >> >>>>>> 'interconnects' property to the binding to allow platform DT nodes >>>>>> to describe this path. >>>>>> >>>>>> Reviewed-by: Krzysztof Kozlowski >>>>>> Signed-off-by: Bibek Kumar Patro >>>>>> --- >>>>>> .../devicetree/bindings/iommu/arm,smmu.yaml | 27 ++++++++++++++++++++++ >>>>>> 1 file changed, 27 insertions(+) >>>>>> >>> >>