On Wed, 2021-09-01 at 18:16 +0800, Chen-Yu Tsai wrote:

On Wed, Sep 1, 2021 at 5:04 PM moudy ho [off-list ref]
wrote:

quoted

On Mon, 2021-08-30 at 10:05 -0500, Rob Herring wrote:

quoted

On Mon, Aug 30, 2021 at 2:58 AM moudy ho [off-list ref]
wrote:

quoted

On Tue, 2021-08-24 at 13:02 -0500, Rob Herring wrote:

quoted

On Tue, Aug 24, 2021 at 06:00:25PM +0800, Moudy Ho wrote:

quoted

This patch adds DT binding document for Media Data Path 3
(MDP3)
a unit in multimedia system used for scaling and color
format
convert.

Signed-off-by: Moudy Ho <redacted>
---
 .../bindings/media/mediatek,mdp3-ccorr.yaml   |  57 +++++
 .../bindings/media/mediatek,mdp3-rdma.yaml    | 207
++++++++++++++++++
 .../bindings/media/mediatek,mdp3-rsz.yaml     |  65 ++++++
 .../bindings/media/mediatek,mdp3-wdma.yaml    |  71 ++++++
 .../bindings/media/mediatek,mdp3-wrot.yaml    |  71 ++++++
 5 files changed, 471 insertions(+)
 create mode 100644
Documentation/devicetree/bindings/media/mediatek,mdp3-
ccorr.yaml
 create mode 100644
Documentation/devicetree/bindings/media/mediatek,mdp3-
rdma.yaml
 create mode 100644
Documentation/devicetree/bindings/media/mediatek,mdp3-
rsz.yaml
 create mode 100644
Documentation/devicetree/bindings/media/mediatek,mdp3-
wdma.yaml
 create mode 100644
Documentation/devicetree/bindings/media/mediatek,mdp3-
wrot.yaml

diff --git
a/Documentation/devicetree/bindings/media/mediatek,mdp3-
ccorr.yaml
b/Documentation/devicetree/bindings/media/mediatek,mdp3-
ccorr.yaml
new file mode 100644
index 000000000000..59fd68b46022

--- /dev/null
+++

b/Documentation/devicetree/bindings/media/mediatek,mdp3-
ccorr.yaml

@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id:

https://urldefense.com/v3/__http://devicetree.org/schemas/media/mediatek,mdp3-ccorr.yaml*__;Iw!!CTRNKA9wMg0ARbw!1C0ChLqzi7Zq8D2d4_S4IqCEei4GXdgy3_VCQg8MdsJP7n8TlxbGyajipusfH8hi$

quoted

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quoted

+$schema:

https://urldefense.com/v3/__http://devicetree.org/meta-schemas/core.yaml*__;Iw!!CTRNKA9wMg0ARbw!1C0ChLqzi7Zq8D2d4_S4IqCEei4GXdgy3_VCQg8MdsJP7n8TlxbGyajipi-OInix$

quoted

quoted

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+
+title: Mediatek Media Data Path 3 CCORR Device Tree
Bindings
+
+maintainers:
+  - Daoyuan Huang [off-list ref]
+  - Moudy Ho [off-list ref]
+
+description: |
+  One of Media Data Path 3 (MDP3) components used to do
color
correction with 3X3 matrix.
+
+properties:
+  compatible:
+    items:
+      - enum:
+        - mediatek,mt8183-mdp3-ccorr
+
+  mediatek,mdp3-id:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    maxItems: 1
+    description: |
+      HW index to distinguish same functionality modules.

If we wanted h/w indexes in DT, we'd have a standard
property.
Why
do
you need this?

I'm sorry not quite sure what HW indexes means (something like
aliases?)

It means whatever you said in your description.

And no, I'm not suggesting you use aliases.

Sorry for the inaccuracy described here, the comment i mentioned
before
should be "standard property" instead of "HW index".

quoted

quoted

It was originally used to mark multiple identical modules in
the
MDP
data path algorithm, so that appropriate paths can be
dynamically
dispatched.

If they are identical, then why do you need to distinguish them
in
DT?
If there's some difference you need to know about such as
connections
to other blocks, then describe that. Another common example is
needing
to know what bits/registers to access in a syscon phandle. For
that,
make the register offset or bits be args to the phandle property.

Rob

Integrating the previous discussion, maybe I can revise the
description
to the following:
    description: |
      There may be multiple blocks with the same function but
different
      addresses in MDP3. In order to distinguish the connection
with
      other blocks, a unique ID is needed to dynamically use one or
      more identical blocks to implement multiple pipelines.

With display pipelines it is common to describe the pipeline with an
OF
graph. With the pipeline drawn out, you also get ways to derive
identifiers
for otherwise identical blocks, such as from port IDs.

See Documentation/devicetree/bindings/display/allwinner,sun4i-a10-
display-engine.yaml
and arch/arm/boot/dts/sun9i-a80.dtsi for such an example.


ChenYu

From the MDP routing table defined in mt8183-mmsys.h
([v7,2/5] soc: mediatek: mmsys: Add support for MDP),
It can be seen that each component has its own independent
one-to-many mapping table, and its next-level receiver may
have its own multiple inputs and is difficult to briefly
describe these relationships.
 
In addition, due to hardware limitations, RSZ0 (for example)
cannot be completely regarded as RSZ1 in mmsys, and must be
regarded as an independent entity, an example mentioned
in line #67 from mtk-mdp3-cmdq.c
([v7,5/5] media: platform: mtk-mdp3: Add Mediatek MDP3 driver).

Moudy
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