diff mbox series

[v5,1/2] dt-bindings: memory: mediatek: Add SMI reset and clamp for MT8188

Message ID 20250311122327.20685-2-friday.yang@mediatek.com (mailing list archive)
State New
Headers show
Series Add SMI reset and clamp for MediaTek MT8188 SoC | expand

Commit Message

Friday Yang March 11, 2025, 12:23 p.m. UTC
From: "Friday Yang" <friday.yang@mediatek.com>

On the MediaTek platform, some SMI LARBs are directly connected to
the SMI Common, while others are connected to the SMI Sub-Common,
which in turn is connected to the SMI Common. The hardware block
diagram can be described as follows.

             SMI-Common(Smart Multimedia Interface Common)
                 |
         +----------------+------------------+
         |                |                  |
         |                |                  |
         |                |                  |
         |                |                  |
         |                |                  |
       larb0       SMI-Sub-Common0     SMI-Sub-Common1
                   |      |     |      |             |
                  larb1  larb2 larb3  larb7       larb9

For previous discussion on the direction of the code modifications,
please refer to:
https://lore.kernel.org/all/CAFGrd9qZhObQXvm2_abqaX83xMLqxjQETB2=wXpobDWU1CnvkA@mail.gmail.com/
https://lore.kernel.org/all/CAPDyKFpokXV2gJDgowbixTvOH_5VL3B5H8eyhP+KJ5Fasm2rFg@mail.gmail.com/

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 this
binding. Without these patches, the SMI becomes unstable during camera
stress tests.

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.

This patch primarily add two changes:
1. Add compatible for SMI sub-common on MT8188 SoC.
2. Add 'resets' and 'reset-names' properties for SMI LARBs to
   support SMI reset operations.

Signed-off-by: Friday Yang <friday.yang@mediatek.com>
---
 .../mediatek,smi-common.yaml                  |  2 ++
 .../memory-controllers/mediatek,smi-larb.yaml | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+)

--
2.46.0

Comments

Rob Herring (Arm) March 11, 2025, 8:07 p.m. UTC | #1
On Tue, 11 Mar 2025 20:23:21 +0800, Friday Yang wrote:
> From: "Friday Yang" <friday.yang@mediatek.com>
> 
> On the MediaTek platform, some SMI LARBs are directly connected to
> the SMI Common, while others are connected to the SMI Sub-Common,
> which in turn is connected to the SMI Common. The hardware block
> diagram can be described as follows.
> 
>              SMI-Common(Smart Multimedia Interface Common)
>                  |
>          +----------------+------------------+
>          |                |                  |
>          |                |                  |
>          |                |                  |
>          |                |                  |
>          |                |                  |
>        larb0       SMI-Sub-Common0     SMI-Sub-Common1
>                    |      |     |      |             |
>                   larb1  larb2 larb3  larb7       larb9
> 
> For previous discussion on the direction of the code modifications,
> please refer to:
> https://lore.kernel.org/all/CAFGrd9qZhObQXvm2_abqaX83xMLqxjQETB2=wXpobDWU1CnvkA@mail.gmail.com/
> https://lore.kernel.org/all/CAPDyKFpokXV2gJDgowbixTvOH_5VL3B5H8eyhP+KJ5Fasm2rFg@mail.gmail.com/
> 
> 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 this
> binding. Without these patches, the SMI becomes unstable during camera
> stress tests.
> 
> 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.
> 
> This patch primarily add two changes:
> 1. Add compatible for SMI sub-common on MT8188 SoC.
> 2. Add 'resets' and 'reset-names' properties for SMI LARBs to
>    support SMI reset operations.
> 
> Signed-off-by: Friday Yang <friday.yang@mediatek.com>
> ---
>  .../mediatek,smi-common.yaml                  |  2 ++
>  .../memory-controllers/mediatek,smi-larb.yaml | 19 +++++++++++++++++++
>  2 files changed, 21 insertions(+)
> 

Acked-by: Rob Herring (Arm) <robh@kernel.org>
AngeloGioacchino Del Regno March 12, 2025, 10:35 a.m. UTC | #2
Il 11/03/25 13:23, Friday Yang ha scritto:
> From: "Friday Yang" <friday.yang@mediatek.com>
> 
> On the MediaTek platform, some SMI LARBs are directly connected to
> the SMI Common, while others are connected to the SMI Sub-Common,
> which in turn is connected to the SMI Common. The hardware block
> diagram can be described as follows.
> 
>               SMI-Common(Smart Multimedia Interface Common)
>                   |
>           +----------------+------------------+
>           |                |                  |
>           |                |                  |
>           |                |                  |
>           |                |                  |
>           |                |                  |
>         larb0       SMI-Sub-Common0     SMI-Sub-Common1
>                     |      |     |      |             |
>                    larb1  larb2 larb3  larb7       larb9
> 
> For previous discussion on the direction of the code modifications,
> please refer to:
> https://lore.kernel.org/all/CAFGrd9qZhObQXvm2_abqaX83xMLqxjQETB2=wXpobDWU1CnvkA@mail.gmail.com/
> https://lore.kernel.org/all/CAPDyKFpokXV2gJDgowbixTvOH_5VL3B5H8eyhP+KJ5Fasm2rFg@mail.gmail.com/
> 
> 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 this
> binding. Without these patches, the SMI becomes unstable during camera
> stress tests.
> 
> 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.
> 
> This patch primarily add two changes:
> 1. Add compatible for SMI sub-common on MT8188 SoC.
> 2. Add 'resets' and 'reset-names' properties for SMI LARBs to
>     support SMI reset operations.
> 
> Signed-off-by: Friday Yang <friday.yang@mediatek.com>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-common.yaml b/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-common.yaml
index 2f36ac23604c..4392d349878c 100644
--- a/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-common.yaml
+++ b/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-common.yaml
@@ -39,6 +39,7 @@  properties:
           - mediatek,mt8186-smi-common
           - mediatek,mt8188-smi-common-vdo
           - mediatek,mt8188-smi-common-vpp
+          - mediatek,mt8188-smi-sub-common
           - mediatek,mt8192-smi-common
           - mediatek,mt8195-smi-common-vdo
           - mediatek,mt8195-smi-common-vpp
@@ -107,6 +108,7 @@  allOf:
         compatible:
           contains:
             enum:
+              - mediatek,mt8188-smi-sub-common
               - mediatek,mt8195-smi-sub-common
     then:
       required:
diff --git a/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-larb.yaml b/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-larb.yaml
index 2381660b324c..f4f0ed0f1fd9 100644
--- a/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-larb.yaml
+++ b/Documentation/devicetree/bindings/memory-controllers/mediatek,smi-larb.yaml
@@ -69,6 +69,12 @@  properties:
     description: the hardware id of this larb. It's only required when this
       hardware id is not consecutive from its M4U point of view.

+  resets:
+    maxItems: 1
+
+  reset-names:
+    const: larb
+
 required:
   - compatible
   - reg
@@ -125,6 +131,19 @@  allOf:
       required:
         - mediatek,larb-id

+  - if:  # only for image, camera and ipe subsys
+      properties:
+        compatible:
+          const: mediatek,mt8188-smi-larb
+        mediatek,larb-id:
+          enum:
+            [ 9, 10, 11, 12, 13, 16, 17, 18, 19, 20 ]
+
+    then:
+      required:
+        - resets
+        - reset-names
+
 additionalProperties: false

 examples: