.../mediatek,smi-common.yaml | 2 + .../memory-controllers/mediatek,smi-larb.yaml | 19 +++ drivers/memory/mtk-smi.c | 151 ++++++++++++++++++ 3 files changed, 172 insertions(+)
Based on tag: next-20250916, 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 in v11: - Add error checking in the 'mtk_smi_genpd_callback' function and use 'switch-case' statement instead of 'if-else'. - Use 'larb->larb_gen->clamp_port[larb->larbid]' to determine whether smi larb requires clamp and reset operations or not in 'mtk_smi_larb_probe'. Remove the '_optional' suffix from the function name. - Replace 'devm_reset_control_get_optional_exclusive' with 'devm_reset_control_get_exclusive' in 'mtk_smi_larb_parse_reset', return the error code if it fails to get the reset controller. - Remove genpd callback when smi larb probe fails. Changes in v10: - Rename 'smi_comm_inport_id' to 'smi_comm_in_port_id'. - Return 0 when it fails to get 'larb_id' in 'mtk_smi_larb_parse_clamp_optional'. - Link to v10: https://lore.kernel.org/lkml/20250806085946.11383-1-friday.yang@mediatek.com/ Changes in v9: - Add 'dev_pm_genpd_remove_notifier' in 'mtk_smi_larb_remove'. - Remove unused macros. - Rename 'sub_comm_syscon' to 'smi_comm_syscon'. - Rename 'sub_comm_inport_id' to 'smi_comm_inport_id'. - Add more detailed descriptions in change log. - Fix incorrect tags. - Link to v9: https://lore.kernel.org/lkml/20250804125215.23076-1-friday.yang@mediatek.com/ Changes in v8: - Fix incorrect tags. - Link to v8: https://lore.kernel.org/lkml/20250521063347.31578-1-friday.yang@mediatek.com/ Changes in v7: - 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 v7 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. - Link to v7: https://lore.kernel.org/lkml/20250430094545.23932-1-friday.yang@mediatek.com/ Changes in v6: - Fix coding style. - Add another patch to replace 'pm_runtime_enable' with 'devm_pm_runtime_enable'. - Link to v6: https://lore.kernel.org/lkml/20250408033206.12176-1-friday.yang@mediatek.com/ Changes in v5: - Use 'devm_pm_runtime_enable' instead of 'pm_runtime_enable'. - Remove 'pm_runtime_disable' in 'mtk_smi_common_remove' and 'mtk_smi_larb_remove'. - Link to v5: https://lore.kernel.org/lkml/20250311122327.20685-1-friday.yang@mediatek.com/ Changes in v4: - Use 'devm_reset_control_get_optional_exclusive' instead of 'devm_reset_control_get'. - Link to v4: https://lore.kernel.org/lkml/20250221074846.14105-1-friday.yang@mediatek.com/ Changes in v3: - Remove redundant descriptions for 'resets' and 'reset-names'. - Modify the requirements for 'resets' and 'reset-names'. - Rename 'mtk_smi_larb_parse_clamp' to 'mtk_smi_larb_parse_clamp_optional'. - Rename 'mtk_smi_larb_parse_reset' to 'mtk_smi_larb_parse_reset_optional'. - Merge 'mtk_smi_larb_clamp_protect_enable' and 'mtk_smi_larb_clamp_protect_disble' into one function. - Modify the definition for mtk_smi_larb_clamp_port_mt8188, use 'larbid' as the index of the array. - Use 'syscon_regmap_lookup_by_phandle' instead of 'device_node_to_regmap'. - Do Not parse 'resets', just check the return value of 'devm_reset_control_get'. - Add 'has_gals' flag for 'mtk_smi_sub_common_mt8188'. - Link to v3: https://lore.kernel.org/lkml/20250121064934.13482-1-friday.yang@mediatek.com/ Changes in v2: - According to previous discussions in v1, divided these four patches into two topic separately. - Modify the description for 'resets' in binding. - Add const value 'larb' for 'reset-names' in binding. - Modify requirement for 'resets' and 'reset-names' in binding. - Delete 'mediatek,smi-sub-comm' in binding. - Delete 'mediatek,smi-sub-comm-in-portid' in binding. - Modify the example in binding. - Add 'mtk_smi_larb_clamp_port_mt8188' definition in SMI driver. - Change the way to parse the 'resets' in driver. - Change label from 'err_pm_disable' to 'err_link_remove'. - Link to v2: https://lore.kernel.org/lkml/20241120063701.8194-1-friday.yang@mediatek.com/ Friday Yang (2): dt-bindings: memory: mediatek: Add SMI reset and clamp for MT8188 memory: mtk-smi: mt8188: Add SMI reset and clamp .../mediatek,smi-common.yaml | 2 + .../memory-controllers/mediatek,smi-larb.yaml | 19 +++ drivers/memory/mtk-smi.c | 151 ++++++++++++++++++ 3 files changed, 172 insertions(+) -- 2.46.0
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