[PATCH v8 0/2] Add SMI reset and clamp for MediaTek MT8188 SoC
From: Friday Yang <hidden>
Date: 2025-05-21 06:34:02
Also in:
linux-devicetree, linux-mediatek, lkml
Based on tag: next-20250521, linux-next/master On the MediaTek MT8188 SoC platform, we encountered power-off failures and SMI bus hang issues during camera stress tests. The issue arises because bus glitches are sometimes produced when MTCMOS powers on or off. While this is fairly normal, the software must handle these glitches to avoid mistaking them for transaction signals. What's more, this issue emerged only after the initial upstreaming of SMI driver. The software solutions can be summarized as follows: 1. Use CLAMP to disable the SMI sub-common port after turning off the LARB CG and before turning off the LARB MTCMOS. 2. Use CLAMP to disable/enable the SMI sub-common port. 3. Implement an AXI reset for SMI LARBs. Changes v8: - We replaced 'pm_runtime_enable' with 'devm_pm_runtime_enable' in the v6 patch. This changed the order of cleanup, and reviewers expressed concerns that it could introduce unexpected issues. So I discard this change and continue using 'pm_runtime_enable'. We need to conduct further investigation to determine if there are any issues related to the cleanup order. This might be resolved in the future, but for now, we just maintain the current status. v7: https://lore.kernel.org/lkml/20250430094545.23932-2-friday.yang@mediatek.com/ (local) https://lore.kernel.org/lkml/20250430094545.23932-3-friday.yang@mediatek.com/ (local) friday.yang (2): dt-bindings: memory: mediatek: Add SMI reset and clamp for MT8188 memory: mtk-smi: mt8188: Add SMI reset and clamp for MT8188 .../mediatek,smi-common.yaml | 2 + .../memory-controllers/mediatek,smi-larb.yaml | 19 +++ drivers/memory/mtk-smi.c | 133 ++++++++++++++++++ 3 files changed, 154 insertions(+) -- 2.46.0