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To: Qianhui Xu Cc: linux-phy@lists.infradead.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org References: <179472053649.14538.1565870277822789081@mail.ustc.edu.cn> From: Bryan O'Donoghue Content-Language: en-GB Autocrypt: addr=bod@kernel.org; keydata= xsFNBGRJNSgBEADD7Vm2ZFa+v+JGJ2QYTJqQAkqis/uOHkhdFNXqpBarVBd47QU/DMNU5Rxg jedMQEmHoeDbJ6UOpjbrUQ63c5sgG1JbroHJJctwsEI75OOlekMuebEbjIJBLfgENGwPBMHv piv5TgCWr0VgYaXfp2eh2LINFywzqj823HiDPibQAXDrjzvF1ogksi/6cQZs8d4if8YQkLOr YISFouG+eR0nN1I7mUfIddXOWu6lJeTyqbWVurv58k2ekIXKaOC9ixLHFbcfYV0hOgRaTwQC B8CYF9nfqZla19iItfsN9QxN+ZdQjcRoYipp6HPCMfJlKH7GfaFcW93LKc4DKJ2lVL+pg/OQ lythZbjRPY492NG9kZ65aYstCs90uhMUEVVPuGUw7wBEku+6IEwZfrbMVKeWzLlPyM4Hv9hM 8ktxSmxWsPTPqpBC8eyeAQLalMELAyVcZlkaCtEcbj7w4l/JkYz+4l37obG8ZD+B34udBUUz MsAJ8foDFrBh2MOFA3hxD6G90D23mmWsri7pnKA2tZs92aQX7Ee+FbCyg6g5ln62Sq83ZDbf 53DdBs55EVpBadeInWmXhzCHPQx06H+CwTEjShTYIaMmBfrewvYUDKvFTC5iKQhAEUgt6i94 JsbG7NoeqcxkUMcBOEUQ3uCQG1D70ugspgXc0wd3Rimiq6535wARAQABzSFCcnlhbiBPJ0Rv bm9naHVlIDxib2RAa2VybmVsLm9yZz7CwZEEEwEIADsWIQTmk/sqq6Nt4Rerb7QicTuzoY3I OgUCZ+R+mwIbAwULCQgHAgIiAgYVCgkICwIEFgIDAQIeBwIXgAAKCRAicTuzoY3IOimUD/94 BwVEJX31JRe2sxbB/e1w2p8x1bxvTw5AeIzpV3ox7coJg1bSU2mnGuj1V4o0Yxf/3zmcJzCN VfVjwRF8Ii3GnC7uUXk2t+87piQfKTyJAYQABhZUKgoVJbjJq/S+C3XCKIyBA+EiezoUsgsA jTzwU+FzV7zVWIXFPJNtBERLwboE9w9U3KjAExOa1kSY8eLrsg6kOwlOHWy5UsQqYOjrS96M mzm2xuc1+RCjrndAyYhCnrOKvJ67HsPnBeJCjw7ImGD/U1GchwYbX8o3DO3JNHm3qfC86ZqX 2sCouENg4OzgPTtLKUrueM6xsu6KMM7gj17vxsiR3KQEoJnnMB8D1xtBofN3mFZE0wD9M24m 8yGunZbtntMCUHzIrlJgAPwKWKuGOYtA8UgMTFkccnUJtQrg9KotKtEF/FuftG9zLG9XEkt4 5ZdNgbSoLWgelu3T47mbOJ8LHhiLaCWP7yrovtVAvLUQ1BsiA42u8ECrFCFvQj9nrejE/ICv kP+uqcKtdDvP9HrIGycF1WZyfZLp0RvopKW92FLvI4I1QFWJ+wenk6+LGyJ5bzlrWzevjxmf nHcXE6sJBHrE7eijlbbImDAi3uLYN8Nd9Dm11IDAy4GAIQxSiQn0yblDhPiyGtchy80EVkCm g9k17Wol+2E2mC4DKgVdCkyUtTRSLgsJCs7BTQRkSTUoARAAuTnmWHBS6izRcEE93ajpzI7h dgQO4U3IRvOEsvIKR5NGcNEs0ngGebwsZ/lVULjN4vYU0LleqVhPBidNXUoZCN3A0F0Z2Ov8 NZdef+2EhQPBVWxFO7JBzhe8Z3ALj+wFtlg8akJjBzU56azW/iJzAobqHVrudzKoO2b1/CMg VbiAQ+RXjgfN5kY/HqYDU7mw+hXuUV9PbtX1L8xqQQac95oM9rHzKHHpiVwxTeJnGQsa+THi Kze+YET3rCoGHMvOQEJhdrucTv5FpAakKdkOFNel9FFckLRKEuWgCzhpFsjQ7xbirQgFUxG9 vlk1+q4hMRGNyEqoD6svYEeqbiUSd0oPUJeioiC3rNMRCNHLVrfZ2J6SCPkxfda08uzSdDQU 1/YPjOh8ZtQDMu7WctZ3XO288Z1gyBR49V7fbFs2w4sQxG+h/enlxqP7fdw1mjUlZjU5huCJ ielS0oEaIpmUpkugli7x4WhwLnhK2EbSoz7nLBC0y+ALUOdMlz/Y1l9xRt+bkDhpmf4O4IcI MxgZ0QMLq8rHDkGaEbsgZZHQPS58T0XE3IP30Q9SNxsruCMXtd2hYtBssf/wohc6JVsTtMg2 VYTPDPIFNZFSXupEJB7jlqpDWJ8ooJfJRLBatbjT5+mVQaMYB7Hs/t+zWYWaJKHyc8O6WLEC NUV5Tdt5EkkAEQEAAcLBdgQYAQoAIBYhBOaT+yqro23hF6tvtCJxO7Ohjcg6BQJkSTUoAhsM AAoJECJxO7Ohjcg6LuIQALnXt36OUuK43wqw6UYt0cnN6EbUqJHApAF5eNFn0jCCB2XELjSz JKJwuNAweowBdabiBniJ+501WIW+ewEsz1uby5fUQjZuCEsIkuaIluyfUFPb73qrQyAGuusd 7teA4WT+/jUku9g7lX5sVoRCrKQPkd16f6Bzfztyqyjcn43/X5yQI+wlboQ6HuKe/3I3yiOx OgmCHzOawpC9PvhEcKj79RLM3Zz5Ts5AuHpRX70Jz8Be76LwVFLp5Msx3S24ZTU1lBo2uiJ3 xSkay2lTpyVWRPx9vgcwzxGguOPJQJwsQeLb7wpoJMPpD3ERoaRii7Q7hvmxklpZjhKYWB3d t6nQ497Ek9loCrp3MIjRCSDN5xEGffiHks9yTeGMUQwO4tX8RE04uOJPkUY7uCFzFqN6/qey X3oFfPgkULMdiHofPAL1OskZSTzGPSfTYRE46NCJw8yoZBQ/oOyWeqaUQbK0wmW/g81wm8p7 LKSGEglMpiX07M1AotgvylN5C8fjbouoK+/RAMsXkk8jba6rPfuuXPaDjCyyKn6zSVHETnHW 3AJbgVY50T8STpnxayBQvWbCvu+6NOEjXCbyaOJig+5l0zlGN9XHjdANXC5HnwmyaGRL9YDq Jh2nVXVJDincOdQRdKcJjYLqaOAoWrYWSDi1iZGspHBTDrnOvfMQzzHY In-Reply-To: <179472053649.14538.1565870277822789081@mail.ustc.edu.cn> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 15/11/2026 05:28, Qianhui Xu wrote: > Hi Bryan, > > SM8750 (Lenovo TB322FC, mainline bring-up) carries a CSIPHY whose vendor driver > describes its lane table as csiphy_2ph_v2_4_0_reg. Upstream's lane_regs_x1e80100[] > in phy-qcom-mipi-csi2-3ph-dphy.c is the 2.1.2 generation, so the two differ. > Before sending anything I'd like your preference on the shape. OK I's not clear to me if what is meant is stuff that Hangxiang is working on There's a v25 on list for sm8750 https://patchwork.linuxtv.org/user/todo/linux-media/?series=33877 New work/additional-work/bug-fixes on top of that branch or absorption of downstream work ? > What I measured (vendor camera_dlkm module, unstripped; 103-entry table, 1648 B): > > - address set identical, 103/103; (addr, data, param_type) differs in 13 entries > - 0x0000/0x0400/0x0800/0x0c00 : 0x8e -> 0x8c (DEFAULT, 4) > - 0x0008/0x0408/0x0808/0x0c08/0x0e08 : 0x10 -> 0x19 (SETTLE_CNT_LOWER_BYTE, 5) > - 0x0060/0x0460/0x0860/0x0c60 : 0xbd -> 0xfd (SKEW_CAL, 4) > > Those three values also track the vendor's own generation numbering across every > 2ph table in that module: v2.1.x = (8e,10,bd), v2.2.x = (8e,19,bd), > v2.3.0/2.4.0/2.4.1 = (8c,19,fd). So they look like generation markers rather than > per-SoC tuning. OK but I still don't really get the context - against 7.4-rc3 or against that with Hangxiang's changes or something else ? I think I already indicated the stuff on-list is good to go so if you have more fixes/changes/enhancements please ensure to base off of those. > One thing worth stating up front, because it bounds what the patch can claim: > in phy_qcom_mipi_csi2_gen2_config_lanes() the SETTLE entries are overwritten with the > value computed from the link frequency, and SKEW entries are skipped (still > "TODO: support application of skew from dt flag"). Only the four 0x0000 writes > (0x8c) actually change behaviour today. > > Questions: > > 1) Shape: a new lane_regs_sm8750[] plus a mipi_csi2_dphy_3nm_sm8750 soc cfg > (compatible "qcom,sm8750-csi2-phy" with "qcom,kaanapali-csi2-phy" as fallback), > or would you rather see the difference expressed per generation > (e.g. lane_regs_2_4_0[] shared by any future SoC on that generation)? I think I pointed you at Hangxiang's series before, if not please check it out now. > > 2) Evidence level: with only one SM8750 unit I can measure a 30 fps capture > regression, nothing more. Is "matches the vendor table for that generation" > an acceptable justification for the 0x0000 value change, or do you want the > SETTLE/SKEW entries dropped from the table until the driver actually applies > them (so the patch carries no dead data)? > 3) Binding: standalone "qcom,sm8750-csi2-phy" const vs. an items entry with the > kaanapali fallback. I see a kaanapali series in flight touching the same oneOf, > so I'd rather follow whatever shape that series lands with. > > I have a two-patch draft ready (binding + driver) that applies on 7.4-rc3 and passes > checkpatch --strict, W=1 and dt_binding_check; I'll hold it until you answer. Please align your work with the on-list stuff. > Disclosure: this mail was written with AI assistance; the author reviewed and > verified every statement, and all measurements and decisions are the author's. I'm finding the LLM output pretty difficult to understand to be honest. But if I've understood you here I think you've missed Hangxiang/Qualcomm's work for 8750 so please pick up on that and see if there are still gaps for you. --- bod