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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-Spam-Info: AW1haW4tMjYwOTA4MDE4OSBTYWx0ZWRfX+MSJmQNa/fcR NFmhdJRu1/TBCL4RVF3qEnsk31nQbmg4LXCcVEhRVGFSWK8ag6az9rSCsOshW7RRPYUwd7e8JZi yLJ2K2AhG64Il7EMfAiizJaqjGdo6SU= X-Proofpoint-ORIG-GUID: g6uiEen6q6WfI2PL2EtHVLlHR3n9-u52 X-Authority-Analysis: v=2.4 cv=TammcxQh c=1 sm=1 tr=0 ts=6aa04568 cx=c_pps a=0uOsjrqzRL749jD1oC5vDA==:117 a=66SLN7faITJN3pPvMqR9OA==:17 a=IkcTkHD0fZMA:10 a=VdqzKS8jKosA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=DJpcGTmdVt4CTyJn9g5Z:22 a=jJ3HrK66ljBcDBb3hHsA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=mQ_c8vxmzFEMiUWkPHU9:22 X-Proofpoint-GUID: g6uiEen6q6WfI2PL2EtHVLlHR3n9-u52 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTA4MDE4OSBTYWx0ZWRfXxB0M8O6QhJq2 ly04/7sL+RP9A20SCy4ZB8vm+o/jyrTF8Il3cBDr/zDxiCysXQb+gG31Yx0e30vfgpVBqvvSOVo 5JjpbPaKDk8iThiEba6N172eXqIfssArvhaUJ7a2TmBxG0+eUMREo1iN/LhkJc6gnivfIK8T3wN AvEc7FvCHnwIs0tL2MN5/E6tszYsJowT+LqzK9us/ZItPfv1lqeK5NqXaurleZfp8W+Zs/IIVlE 7jgiGtlGIjlpBweGetQxepe+52Fpf0x7MV5brRzPQkZkQ5bGzVos8poWdybp6bNfgulZwuA31xc m5+VCdo7mmu8Mr2P/ddGDl2sC2MNgQHbZla0FPv0Ovr5FzUGgIkm/1RgctM56s4kdnql3hrz7Uo wEVl/LOgvncsMZO2o0ouAy7uXB8Ey/xNFhGTVf5I/mgZysrR+Kf0wr1/9p9Od6OBSsVzF/QsTXo BKZ8GOSbXDdaiPSYHbA== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-09-08_03,2026-09-08_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 priorityscore=1501 lowpriorityscore=0 phishscore=0 adultscore=0 spamscore=0 suspectscore=0 bulkscore=0 malwarescore=0 impostorscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2609080189 >>>>> >>>>> properties: >>>>> compatible: >>>>> @@ -20,9 +28,42 @@ properties: >>>>> minItems: 1 >>>>> maxItems: 2 >>>> >>>> As I said last time, different hardware, different programming >>>> interface, different features, so a different compatible. >>> >>> >>> The APM DAI block is the same packet format. The driver uses a single >>> of_device_id entry with no match data; there is no code path dispatched >>> by the compatible string. >>> >>> The iommu vs VMID distinction is a property of the memory topology, >>> not the DAI hardware, and is already described by the mutually exclusive >>> iommus / qcom,vmids properties. The DSP identity (ADSP vs mDSP) is >>> carried by the GPR node's qcom,domain property and read at the send >>> layer — the DAI node itself does not need to know which DSP it talks to. >> >> I am still trying to grasp it. You have a device "APM" and it accesses >> PCM buffers or other memory in some way needing IOMMU for that. >> >> Now you add something which you call EXACTLY the same device, no >> difference at all, same "APM", but this time this device operates >> completely different, because it does not use IOMMU, but talks with >> firmware via SCM. >> >> Well, I really do not see how is this still exactly the same or even >> compatible device. >> >> The way device accesses its data is part of the programming model and >> different programming models have different compatibles. > > > Additionally, as explained to me in off-list channel, the qcom,vmids is > not a hardware property at all (because hardware is the same), thus does > not look suitable for DT. > I understand the concern. The qcom,vmids property describes which Virtual machines the SoC firmware has configured to own the memory space on a given board. similar to how iommus describes which SMMU the device is wired to. There is existing precedent for this in the tree: - fastrpc (Documentation/devicetree/bindings/misc/qcom,fastrpc.yaml) uses qcom,vmids to describe remote processor VMIDs. The driver reads them from DT and calls qcom_scm_assign_mem(). The compatible stays generic (qcom,fastrpc). - rmtfs-mem (Documentation/devicetree/bindings/reserved-memory/qcom,rmtfs-mem.yaml) uses qcom,vmid the same way with a single generic compatible (qcom,rmtfs-mem). We are following the same pattern here. Happy to discuss further if you see a difference between these cases and ours. Thanks & Regards Ajay Kumar Nandam > Best regards, > Krzysztof