Subject: [PATCH v5 0/3] drm/mediatek: Add support for OF graphs

Changes in v5:
- Fixed commit [2/3], changed allOf -> anyOf to get the
intended allowance in the binding

Changes in v4:
- Fixed a typo that caused pure OF graphs pipelines multiple
concurrent outputs to not get correctly parsed (port->id);
- Added OVL_ADAPTOR support for OF graph specified pipelines;
- Now tested with fully OF Graph specified pipelines on MT8195
Chromebooks and MT8395 boards;
- Rebased on next-20240516

Changes in v3:
- Rebased on next-20240502 because of renames in mediatek-drm

Changes in v2:
- Fixed wrong `required` block indentation in commit [2/3]


The display IPs in MediaTek SoCs are *VERY* flexible and those support
being interconnected with different instances of DDP IPs (for example,
merge0 or merge1) and/or with different DDP IPs (for example, rdma can
be connected with either color, dpi, dsi, merge, etc), forming a full
Display Data Path that ends with an actual display.

This series was born because of an issue that I've found while enabling
support for MT8195/MT8395 boards with DSI output as main display: the
current mtk_drm_route variations would not work as currently, the driver
hardcodes a display path for Chromebooks, which have a DisplayPort panel
with DSC support, instead of a DSI panel without DSC support.

There are other reasons for which I wrote this series, and I find that
hardcoding those paths - when a HW path is clearly board-specific - is
highly suboptimal. Also, let's not forget about keeping this driver from
becoming a huge list of paths for each combination of SoC->board->disp
and... this and that.

For more information, please look at the commit description for each of
the commits included in this series.

This series is essential to enable support for the MT8195/MT8395 EVK,
Kontron i1200, Radxa NIO-12L and, mainly, for non-Chromebook boards
and Chromebooks to co-exist without conflicts.

Besides, this is also a valid option for MT8188 Chromebooks which might
have different DSI-or-eDP displays depending on the model (as far as I
can see from the mtk_drm_route attempt for this SoC that is already
present in this driver).

This series was tested on MT8195 Cherry Tomato and on MT8395 Radxa
NIO-12L with both hardcoded paths, OF graph support and partially
hardcoded paths, and pure OF graph support including pipelines that
require OVL_ADAPTOR support.

AngeloGioacchino Del Regno (3):
dt-bindings: display: mediatek: Add OF graph support for board path
dt-bindings: arm: mediatek: mmsys: Add OF graph support for board path
drm/mediatek: Implement OF graphs support for display paths

.../bindings/arm/mediatek/mediatek,mmsys.yaml | 28 ++
.../display/mediatek/mediatek,aal.yaml | 40 +++
.../display/mediatek/mediatek,ccorr.yaml | 21 ++
.../display/mediatek/mediatek,color.yaml | 22 ++
.../display/mediatek/mediatek,dither.yaml | 22 ++
.../display/mediatek/mediatek,dpi.yaml | 25 +-
.../display/mediatek/mediatek,dsc.yaml | 24 ++
.../display/mediatek/mediatek,dsi.yaml | 27 +-
.../display/mediatek/mediatek,ethdr.yaml | 22 ++
.../display/mediatek/mediatek,gamma.yaml | 19 ++
.../display/mediatek/mediatek,merge.yaml | 23 ++
.../display/mediatek/mediatek,od.yaml | 22 ++
.../display/mediatek/mediatek,ovl-2l.yaml | 22 ++
.../display/mediatek/mediatek,ovl.yaml | 22 ++
.../display/mediatek/mediatek,postmask.yaml | 21 ++
.../display/mediatek/mediatek,rdma.yaml | 22 ++
.../display/mediatek/mediatek,ufoe.yaml | 21 ++
drivers/gpu/drm/mediatek/mtk_disp_drv.h | 1 +
.../gpu/drm/mediatek/mtk_disp_ovl_adaptor.c | 40 ++-
drivers/gpu/drm/mediatek/mtk_dpi.c | 16 +-
drivers/gpu/drm/mediatek/mtk_drm_drv.c | 282 ++++++++++++++++--
drivers/gpu/drm/mediatek/mtk_drm_drv.h | 2 +-
drivers/gpu/drm/mediatek/mtk_dsi.c | 10 +-
23 files changed, 713 insertions(+), 41 deletions(-)

--
2.45.1



Subject: [PATCH v5 1/3] dt-bindings: display: mediatek: Add OF graph support for board path

The display IPs in MediaTek SoCs support being interconnected with
different instances of DDP IPs (for example, merge0 or merge1) and/or
with different DDP IPs (for example, rdma can be connected with either
color, dpi, dsi, merge, etc), forming a full Display Data Path that
ends with an actual display.

The final display pipeline is effectively board specific, as it does
depend on the display that is attached to it, and eventually on the
sensors supported by the board (for example, Adaptive Ambient Light
would need an Ambient Light Sensor, otherwise it's pointless!), other
than the output type.

Add support for OF graphs to most of the MediaTek DDP (display) bindings
to add flexibility to build custom hardware paths, hence enabling board
specific configuration of the display pipeline and allowing to finally
migrate away from using hardcoded paths.

Reviewed-by: Rob Herring (Arm) <[email protected]>
Reviewed-by: Alexandre Mergnat <[email protected]>
Tested-by: Alexandre Mergnat <[email protected]>
Signed-off-by: AngeloGioacchino Del Regno <[email protected]>
---
.../display/mediatek/mediatek,aal.yaml | 40 +++++++++++++++++++
.../display/mediatek/mediatek,ccorr.yaml | 21 ++++++++++
.../display/mediatek/mediatek,color.yaml | 22 ++++++++++
.../display/mediatek/mediatek,dither.yaml | 22 ++++++++++
.../display/mediatek/mediatek,dpi.yaml | 25 +++++++++++-
.../display/mediatek/mediatek,dsc.yaml | 24 +++++++++++
.../display/mediatek/mediatek,dsi.yaml | 27 ++++++++++++-
.../display/mediatek/mediatek,ethdr.yaml | 22 ++++++++++
.../display/mediatek/mediatek,gamma.yaml | 19 +++++++++
.../display/mediatek/mediatek,merge.yaml | 23 +++++++++++
.../display/mediatek/mediatek,od.yaml | 22 ++++++++++
.../display/mediatek/mediatek,ovl-2l.yaml | 22 ++++++++++
.../display/mediatek/mediatek,ovl.yaml | 22 ++++++++++
.../display/mediatek/mediatek,postmask.yaml | 21 ++++++++++
.../display/mediatek/mediatek,rdma.yaml | 22 ++++++++++
.../display/mediatek/mediatek,ufoe.yaml | 21 ++++++++++
16 files changed, 372 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
index b4c28e96dd55..623cf7e37fe3 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,aal.yaml
@@ -61,6 +61,27 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: AAL input port
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ AAL output to the next component's input, for example could be one
+ of many gamma, overdrive or other blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
@@ -88,5 +109,24 @@ examples:
power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
clocks = <&mmsys CLK_MM_DISP_AAL>;
mediatek,gce-client-reg = <&gce SUBSYS_1401XXXX 0x5000 0x1000>;
+
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ port@0 {
+ reg = <0>;
+ aal0_in: endpoint {
+ remote-endpoint = <&ccorr0_out>;
+ };
+ };
+
+ port@1 {
+ reg = <1>;
+ aal0_out: endpoint {
+ remote-endpoint = <&gamma0_in>;
+ };
+ };
+ };
};
};
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
index 8c2a737237f2..71ea277a5d8e 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ccorr.yaml
@@ -54,6 +54,27 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: CCORR input port
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ CCORR output to the input of the next desired component in the
+ display pipeline, usually only one of the available AAL blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
index b886ca0d89ea..61d040a10c08 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,color.yaml
@@ -64,6 +64,28 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: COLOR input port
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ COLOR output to the input of the next desired component in the
+ display pipeline, for example one of the available CCORR or AAL
+ blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
index 1588b3f7cec7..3d4ab3f86294 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dither.yaml
@@ -55,6 +55,28 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: DITHER input, usually from a POSTMASK or GAMMA block.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ DITHER output to the input of the next desired component in the
+ display pipeline, for example one of the available DSC compressors,
+ DP_INTF, DSI, LVDS or others.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
index 803c00f26206..6607cb1c6e0a 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dpi.yaml
@@ -64,13 +64,34 @@ properties:
Output port node. This port should be connected to the input port of an
attached HDMI, LVDS or DisplayPort encoder chip.

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: DPI input port
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: DPI output to an HDMI, LVDS or DisplayPort encoder input
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
- interrupts
- clocks
- clock-names
- - port
+
+oneOf:
+ - required:
+ - port
+ - required:
+ - ports

additionalProperties: false

@@ -79,7 +100,7 @@ examples:
#include <dt-bindings/interrupt-controller/arm-gic.h>
#include <dt-bindings/clock/mt8173-clk.h>

- dpi0: dpi@1401d000 {
+ dpi: dpi@1401d000 {
compatible = "mediatek,mt8173-dpi";
reg = <0x1401d000 0x1000>;
interrupts = <GIC_SPI 194 IRQ_TYPE_LEVEL_LOW>;
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsc.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsc.yaml
index 2cbdd9ee449d..846de6c17d93 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsc.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsc.yaml
@@ -49,6 +49,30 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ Display Stream Compression input, usually from one of the DITHER
+ or MERGE blocks.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ Display Stream Compression output to the input of the next desired
+ component in the display pipeline, for example to MERGE, DP_INTF,
+ DPI or DSI.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.yaml
index 8611319bed2e..2e9d3d23cbc1 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,dsi.yaml
@@ -76,6 +76,26 @@ properties:
Output port node. This port should be connected to the input
port of an attached DSI panel or DSI-to-eDP encoder chip.

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input ports can have multiple endpoints, each of those connects
+ to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: DSI input port, usually from DITHER, DSC or MERGE
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ DSI output to an attached DSI panel, or a DSI-to-X encoder chip
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
@@ -85,7 +105,12 @@ required:
- clock-names
- phys
- phy-names
- - port
+
+oneOf:
+ - required:
+ - port
+ - required:
+ - ports

unevaluatedProperties: false

diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ethdr.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ethdr.yaml
index 677882348ede..98db47894eeb 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ethdr.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ethdr.yaml
@@ -110,6 +110,28 @@ properties:
include/dt-bindings/gce/<chip>-gce.h, mapping to the register of display
function block.

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: ETHDR input, usually from one of the MERGE blocks.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ ETHDR output to the input of the next desired component in the
+ display pipeline, for example one of the available MERGE blocks,
+ or others.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,gamma.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,gamma.yaml
index b8b8e83ebc3f..17f299abda11 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,gamma.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,gamma.yaml
@@ -64,6 +64,25 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: GAMMA input, usually from one of the AAL blocks.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ GAMMA output to the input of the next desired component in the
+ display pipeline, for example one of the available DITHER or
+ POSTMASK blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,merge.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,merge.yaml
index dae839279950..0de9f64f3f84 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,merge.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,merge.yaml
@@ -77,6 +77,29 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ MERGE input port, usually from DITHER, DPI, DSC, DSI, MDP_RDMA,
+ ETHDR or even from a different MERGE block
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ MERGE output to a DSC, DPI, DP_INTF, DSI, ETHDR, Write DMA, or
+ a different MERGE block, or others.
+
+ required:
+ - port@0
+ - port@1
+
resets:
description: reset controller
See Documentation/devicetree/bindings/reset/reset.txt for details.
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,od.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,od.yaml
index 831c653caffd..71534febd49c 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,od.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,od.yaml
@@ -38,6 +38,28 @@ properties:
items:
- description: OD Clock

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: OD input port, usually from an AAL block
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ OD output to the input of the next desired component in the
+ display pipeline, for example one of the available RDMA or
+ other blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl-2l.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl-2l.yaml
index c7dd0ef02dcf..bacdfe7d08a6 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl-2l.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl-2l.yaml
@@ -57,6 +57,28 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: OVL input port from MMSYS, VDOSYS or other OVLs
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ OVL output to the input of the next desired component in the
+ display pipeline, for example one of the available COLOR, RDMA
+ or WDMA blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl.yaml
index c471a181d125..e93f0247bdcc 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ovl.yaml
@@ -74,6 +74,28 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: OVL input port from MMSYS or one of multiple VDOSYS
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ OVL output to the input of the next desired component in the
+ display pipeline, for example one of the available COLOR, RDMA
+ or WDMA blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,postmask.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,postmask.yaml
index 11fe32e50a59..fb6fe4742624 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,postmask.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,postmask.yaml
@@ -52,6 +52,27 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: POSTMASK input port, usually from GAMMA
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ POSTMASK output to the input of the next desired component in the
+ display pipeline, for example one of the available DITHER blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,rdma.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,rdma.yaml
index 39dbb5c8bcf8..edb8d3b67025 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,rdma.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,rdma.yaml
@@ -86,6 +86,28 @@ properties:
$ref: /schemas/types.yaml#/definitions/phandle-array
maxItems: 1

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: RDMA input port, usually from MMSYS, OD or OVL
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ RDMA output to the input of the next desired component in the
+ display pipeline, for example one of the available COLOR, DPI,
+ DSI, MERGE or UFOE blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
diff --git a/Documentation/devicetree/bindings/display/mediatek/mediatek,ufoe.yaml b/Documentation/devicetree/bindings/display/mediatek/mediatek,ufoe.yaml
index 39e3e2d4a0db..61a5e22effbf 100644
--- a/Documentation/devicetree/bindings/display/mediatek/mediatek,ufoe.yaml
+++ b/Documentation/devicetree/bindings/display/mediatek/mediatek,ufoe.yaml
@@ -43,6 +43,27 @@ properties:
items:
- description: UFOe Clock

+ ports:
+ $ref: /schemas/graph.yaml#/properties/ports
+ description:
+ Input and output ports can have multiple endpoints, each of those
+ connects to either the primary, secondary, etc, display pipeline.
+
+ properties:
+ port@0:
+ $ref: /schemas/graph.yaml#/properties/port
+ description: UFOE input, usually from one of the RDMA blocks.
+
+ port@1:
+ $ref: /schemas/graph.yaml#/properties/port
+ description:
+ UFOE output to the input of the next desired component in the
+ display pipeline, usually one of the available DSI blocks.
+
+ required:
+ - port@0
+ - port@1
+
required:
- compatible
- reg
--
2.45.1


Subject: [PATCH v5 3/3] drm/mediatek: Implement OF graphs support for display paths

It is impossible to add each and every possible DDP path combination
for each and every possible combination of SoC and board: right now,
this driver hardcodes configuration for 10 SoCs and this is going to
grow larger and larger, and with new hacks like the introduction of
mtk_drm_route which is anyway not enough for all final routes as the
DSI cannot be connected to MERGE if it's not a dual-DSI, or enabling
DSC preventively doesn't work if the display doesn't support it, or
others.

Since practically all display IPs in MediaTek SoCs support being
interconnected with different instances of other, or the same, IPs
or with different IPs and in different combinations, the final DDP
pipeline is effectively a board specific configuration.

Implement OF graphs support to the mediatek-drm drivers, allowing to
stop hardcoding the paths, and preventing this driver to get a huge
amount of arrays for each board and SoC combination, also paving the
way to share the same mtk_mmsys_driver_data between multiple SoCs,
making it more straightforward to add support for new chips.

Reviewed-by: Alexandre Mergnat <[email protected]>
Tested-by: Alexandre Mergnat <[email protected]>
Signed-off-by: AngeloGioacchino Del Regno <[email protected]>
---
drivers/gpu/drm/mediatek/mtk_disp_drv.h | 1 +
.../gpu/drm/mediatek/mtk_disp_ovl_adaptor.c | 40 ++-
drivers/gpu/drm/mediatek/mtk_dpi.c | 16 +-
drivers/gpu/drm/mediatek/mtk_drm_drv.c | 282 ++++++++++++++++--
drivers/gpu/drm/mediatek/mtk_drm_drv.h | 2 +-
drivers/gpu/drm/mediatek/mtk_dsi.c | 10 +-
6 files changed, 313 insertions(+), 38 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
index 082ac18fe04a..94843974851f 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
+++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
@@ -108,6 +108,7 @@ size_t mtk_ovl_get_num_formats(struct device *dev);

void mtk_ovl_adaptor_add_comp(struct device *dev, struct mtk_mutex *mutex);
void mtk_ovl_adaptor_remove_comp(struct device *dev, struct mtk_mutex *mutex);
+bool mtk_ovl_adaptor_is_comp_present(struct device_node *node);
void mtk_ovl_adaptor_connect(struct device *dev, struct device *mmsys_dev,
unsigned int next);
void mtk_ovl_adaptor_disconnect(struct device *dev, struct device *mmsys_dev,
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
index 02dd7dcdfedb..400519d1ca1f 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
@@ -491,6 +491,38 @@ static int compare_of(struct device *dev, void *data)
return dev->of_node == data;
}

+static int ovl_adaptor_of_get_ddp_comp_type(struct device_node *node,
+ enum mtk_ovl_adaptor_comp_type *ctype)
+{
+ const struct of_device_id *of_id = of_match_node(mtk_ovl_adaptor_comp_dt_ids, node);
+
+ if (!of_id)
+ return -EINVAL;
+
+ *ctype = (enum mtk_ovl_adaptor_comp_type)((uintptr_t)of_id->data);
+
+ return 0;
+}
+
+bool mtk_ovl_adaptor_is_comp_present(struct device_node *node)
+{
+ enum mtk_ovl_adaptor_comp_type type;
+ int ret;
+
+ ret = ovl_adaptor_of_get_ddp_comp_type(node, &type);
+ if (ret)
+ return false;
+
+ if (type >= OVL_ADAPTOR_TYPE_NUM)
+ return false;
+
+ /*
+ * ETHDR and Padding are used exclusively in OVL Adaptor: if this
+ * component is not one of those, it's likely not an OVL Adaptor path.
+ */
+ return type == OVL_ADAPTOR_TYPE_ETHDR || type == OVL_ADAPTOR_TYPE_PADDING;
+}
+
static int ovl_adaptor_comp_init(struct device *dev, struct component_match **match)
{
struct mtk_disp_ovl_adaptor *priv = dev_get_drvdata(dev);
@@ -500,12 +532,11 @@ static int ovl_adaptor_comp_init(struct device *dev, struct component_match **ma
parent = dev->parent->parent->of_node->parent;

for_each_child_of_node(parent, node) {
- const struct of_device_id *of_id;
enum mtk_ovl_adaptor_comp_type type;
- int id;
+ int id, ret;

- of_id = of_match_node(mtk_ovl_adaptor_comp_dt_ids, node);
- if (!of_id)
+ ret = ovl_adaptor_of_get_ddp_comp_type(node, &type);
+ if (ret)
continue;

if (!of_device_is_available(node)) {
@@ -514,7 +545,6 @@ static int ovl_adaptor_comp_init(struct device *dev, struct component_match **ma
continue;
}

- type = (enum mtk_ovl_adaptor_comp_type)(uintptr_t)of_id->data;
id = ovl_adaptor_comp_get_id(dev, node, type);
if (id < 0) {
dev_warn(dev, "Skipping unknown component %pOF\n",
diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
index bfe8653005db..5c86aa0b75b2 100644
--- a/drivers/gpu/drm/mediatek/mtk_dpi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
@@ -705,6 +705,15 @@ static int mtk_dpi_bridge_attach(struct drm_bridge *bridge,
{
struct mtk_dpi *dpi = bridge_to_dpi(bridge);

+ dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 1, -1);
+ if (IS_ERR(dpi->next_bridge)) {
+ /* Old devicetree has only one endpoint */
+ dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 0, 0);
+ if (IS_ERR(dpi->next_bridge))
+ return dev_err_probe(dpi->dev, PTR_ERR(dpi->next_bridge),
+ "Failed to get bridge\n");
+ }
+
return drm_bridge_attach(bridge->encoder, dpi->next_bridge,
&dpi->bridge, flags);
}
@@ -1055,13 +1064,6 @@ static int mtk_dpi_probe(struct platform_device *pdev)
if (dpi->irq < 0)
return dpi->irq;

- dpi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
- if (IS_ERR(dpi->next_bridge))
- return dev_err_probe(dev, PTR_ERR(dpi->next_bridge),
- "Failed to get bridge\n");
-
- dev_info(dev, "Found bridge node: %pOF\n", dpi->next_bridge->of_node);
-
platform_set_drvdata(pdev, dpi);

dpi->bridge.funcs = &mtk_dpi_bridge_funcs;
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
index b5f605751b0a..ce8f3cc6e853 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
@@ -26,6 +26,7 @@

#include "mtk_crtc.h"
#include "mtk_ddp_comp.h"
+#include "mtk_disp_drv.h"
#include "mtk_drm_drv.h"
#include "mtk_gem.h"

@@ -798,12 +799,226 @@ static const struct of_device_id mtk_ddp_comp_dt_ids[] = {
{ }
};

+static int mtk_drm_of_get_ddp_comp_type(struct device_node *node, enum mtk_ddp_comp_type *ctype)
+{
+ const struct of_device_id *of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
+
+ if (!of_id)
+ return -EINVAL;
+
+ *ctype = (enum mtk_ddp_comp_type)((uintptr_t)of_id->data);
+
+ return 0;
+}
+
+static int mtk_drm_of_get_ddp_ep_cid(struct device_node *node,
+ int output_port, enum mtk_crtc_path crtc_path,
+ struct device_node **next, unsigned int *cid)
+{
+ struct device_node *ep_dev_node, *ep_out;
+ enum mtk_ddp_comp_type comp_type;
+ int ret;
+
+ ep_out = of_graph_get_endpoint_by_regs(node, output_port, crtc_path);
+ if (!ep_out)
+ return -ENOENT;
+
+ ep_dev_node = of_graph_get_remote_port_parent(ep_out);
+ if (!ep_dev_node)
+ return -EINVAL;
+
+ /*
+ * Pass the next node pointer regardless of failures in the later code
+ * so that if this function is called in a loop it will walk through all
+ * of the subsequent endpoints anyway.
+ */
+ *next = ep_dev_node;
+
+ if (!of_device_is_available(ep_dev_node))
+ return -ENODEV;
+
+ ret = mtk_drm_of_get_ddp_comp_type(ep_dev_node, &comp_type);
+ if (ret) {
+ if (mtk_ovl_adaptor_is_comp_present(ep_dev_node)) {
+ *cid = (unsigned int)DDP_COMPONENT_DRM_OVL_ADAPTOR;
+ return 0;
+ }
+ return ret;
+ }
+
+ ret = mtk_ddp_comp_get_id(ep_dev_node, comp_type);
+ if (ret < 0)
+ return ret;
+
+ /* All ok! Pass the Component ID to the caller. */
+ *cid = (unsigned int)ret;
+
+ return 0;
+}
+
+/**
+ * mtk_drm_of_ddp_path_build_one - Build a Display HW Pipeline for a CRTC Path
+ * @dev: The mediatek-drm device
+ * @cpath: CRTC Path relative to a VDO or MMSYS
+ * @out_path: Pointer to an array that will contain the new pipeline
+ * @out_path_len: Number of entries in the pipeline array
+ *
+ * MediaTek SoCs can use different DDP hardware pipelines (or paths) depending
+ * on the board-specific desired display configuration; this function walks
+ * through all of the output endpoints starting from a VDO or MMSYS hardware
+ * instance and builds the right pipeline as specified in device trees.
+ *
+ * Return:
+ * * %0 - Display HW Pipeline successfully built and validated
+ * * %-ENOENT - Display pipeline was not specified in device tree
+ * * %-EINVAL - Display pipeline built but validation failed
+ * * %-ENOMEM - Failure to allocate pipeline array to pass to the caller
+ */
+static int mtk_drm_of_ddp_path_build_one(struct device *dev, enum mtk_crtc_path cpath,
+ const unsigned int **out_path,
+ unsigned int *out_path_len)
+{
+ struct device_node *next, *prev, *vdo = dev->parent->of_node;
+ unsigned int temp_path[DDP_COMPONENT_DRM_ID_MAX] = { 0 };
+ unsigned int *final_ddp_path;
+ unsigned short int idx = 0;
+ bool ovl_adaptor_comp_added = false;
+ int ret;
+
+ /* Get the first entry for the temp_path array */
+ ret = mtk_drm_of_get_ddp_ep_cid(vdo, 0, cpath, &next, &temp_path[idx]);
+ if (ret) {
+ if (next && temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
+ dev_err(dev, "Adding OVL Adaptor for %pOF\n", next);
+ ovl_adaptor_comp_added = true;
+ } else {
+ if (next)
+ dev_err(dev, "Invalid component %pOF\n", next);
+ else
+ dev_err(dev, "Cannot find first endpoint for path %d\n", cpath);
+
+ return ret;
+ }
+ }
+ idx++;
+
+ /*
+ * Walk through port outputs until we reach the last valid mediatek-drm component.
+ * To be valid, this must end with an "invalid" component that is a display node.
+ */
+ do {
+ prev = next;
+ ret = mtk_drm_of_get_ddp_ep_cid(next, 1, cpath, &next, &temp_path[idx]);
+ of_node_put(prev);
+ if (ret) {
+ of_node_put(next);
+ break;
+ }
+
+ /*
+ * If this is an OVL adaptor exclusive component and one of those
+ * was already added, don't add another instance of the generic
+ * DDP_COMPONENT_OVL_ADAPTOR, as this is used only to decide whether
+ * to probe that component master driver of which only one instance
+ * is needed and possible.
+ */
+ if (temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
+ if (!ovl_adaptor_comp_added)
+ ovl_adaptor_comp_added = true;
+ else
+ idx--;
+ }
+ } while (++idx < DDP_COMPONENT_DRM_ID_MAX);
+
+ /* If the last entry is not a final display output, the configuration is wrong */
+ switch (temp_path[idx - 1]) {
+ case DDP_COMPONENT_DP_INTF0:
+ case DDP_COMPONENT_DP_INTF1:
+ case DDP_COMPONENT_DPI0:
+ case DDP_COMPONENT_DPI1:
+ case DDP_COMPONENT_DSI0:
+ case DDP_COMPONENT_DSI1:
+ case DDP_COMPONENT_DSI2:
+ case DDP_COMPONENT_DSI3:
+ break;
+ default:
+ dev_err(dev, "Invalid display hw pipeline. Last component: %d (ret=%d)\n",
+ temp_path[idx - 1], ret);
+ return -EINVAL;
+ }
+
+ final_ddp_path = devm_kmemdup(dev, temp_path, idx * sizeof(temp_path[0]), GFP_KERNEL);
+ if (!final_ddp_path)
+ return -ENOMEM;
+
+ dev_dbg(dev, "Display HW Pipeline built with %d components.\n", idx);
+
+ /* Pipeline built! */
+ *out_path = final_ddp_path;
+ *out_path_len = idx;
+
+ return 0;
+}
+
+static int mtk_drm_of_ddp_path_build(struct device *dev, struct device_node *node,
+ struct mtk_mmsys_driver_data *data)
+{
+ struct device_node *ep_node;
+ struct of_endpoint of_ep;
+ bool output_present[MAX_CRTC] = { false };
+ int ret;
+
+ for_each_endpoint_of_node(node, ep_node) {
+ ret = of_graph_parse_endpoint(ep_node, &of_ep);
+ of_node_put(ep_node);
+ if (ret) {
+ dev_err_probe(dev, ret, "Cannot parse endpoint\n");
+ break;
+ }
+
+ if (of_ep.id >= MAX_CRTC) {
+ ret = dev_err_probe(dev, -EINVAL,
+ "Invalid endpoint%u number\n", of_ep.port);
+ break;
+ }
+
+ output_present[of_ep.id] = true;
+ }
+
+ if (ret)
+ return ret;
+
+ if (output_present[CRTC_MAIN]) {
+ ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_MAIN,
+ &data->main_path, &data->main_len);
+ if (ret)
+ return ret;
+ }
+
+ if (output_present[CRTC_EXT]) {
+ ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_EXT,
+ &data->ext_path, &data->ext_len);
+ if (ret)
+ return ret;
+ }
+
+ if (output_present[CRTC_THIRD]) {
+ ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_THIRD,
+ &data->third_path, &data->third_len);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
static int mtk_drm_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *phandle = dev->parent->of_node;
const struct of_device_id *of_id;
struct mtk_drm_private *private;
+ struct mtk_mmsys_driver_data *mtk_drm_data;
struct device_node *node;
struct component_match *match = NULL;
struct platform_device *ovl_adaptor;
@@ -824,7 +1039,31 @@ static int mtk_drm_probe(struct platform_device *pdev)
if (!of_id)
return -ENODEV;

- private->data = of_id->data;
+ mtk_drm_data = (struct mtk_mmsys_driver_data *)of_id->data;
+ if (!mtk_drm_data)
+ return -EINVAL;
+
+ private->data = kmemdup(mtk_drm_data, sizeof(*mtk_drm_data), GFP_KERNEL);
+ if (!private->data)
+ return -ENOMEM;
+
+ /* Try to build the display pipeline from devicetree graphs */
+ if (of_graph_is_present(phandle)) {
+ dev_dbg(dev, "Building display pipeline for MMSYS %u\n",
+ mtk_drm_data->mmsys_id);
+ private->data = devm_kmemdup(dev, mtk_drm_data,
+ sizeof(*mtk_drm_data), GFP_KERNEL);
+ if (!private->data)
+ return -ENOMEM;
+
+ ret = mtk_drm_of_ddp_path_build(dev, phandle, private->data);
+ if (ret)
+ return ret;
+ } else {
+ /* No devicetree graphs support: go with hardcoded paths if present */
+ dev_dbg(dev, "Using hardcoded paths for MMSYS %u\n", mtk_drm_data->mmsys_id);
+ private->data = mtk_drm_data;
+ };

private->all_drm_private = devm_kmalloc_array(dev, private->data->mmsys_dev_num,
sizeof(*private->all_drm_private),
@@ -846,12 +1085,11 @@ static int mtk_drm_probe(struct platform_device *pdev)

/* Iterate over sibling DISP function blocks */
for_each_child_of_node(phandle->parent, node) {
- const struct of_device_id *of_id;
enum mtk_ddp_comp_type comp_type;
int comp_id;

- of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
- if (!of_id)
+ ret = mtk_drm_of_get_ddp_comp_type(node, &comp_type);
+ if (ret)
continue;

if (!of_device_is_available(node)) {
@@ -860,8 +1098,6 @@ static int mtk_drm_probe(struct platform_device *pdev)
continue;
}

- comp_type = (enum mtk_ddp_comp_type)(uintptr_t)of_id->data;
-
if (comp_type == MTK_DISP_MUTEX) {
int id;

@@ -890,22 +1126,24 @@ static int mtk_drm_probe(struct platform_device *pdev)
* blocks have separate component platform drivers and initialize their own
* DDP component structure. The others are initialized here.
*/
- if (comp_type == MTK_DISP_AAL ||
- comp_type == MTK_DISP_CCORR ||
- comp_type == MTK_DISP_COLOR ||
- comp_type == MTK_DISP_GAMMA ||
- comp_type == MTK_DISP_MERGE ||
- comp_type == MTK_DISP_OVL ||
- comp_type == MTK_DISP_OVL_2L ||
- comp_type == MTK_DISP_OVL_ADAPTOR ||
- comp_type == MTK_DISP_RDMA ||
- comp_type == MTK_DP_INTF ||
- comp_type == MTK_DPI ||
- comp_type == MTK_DSI) {
- dev_info(dev, "Adding component match for %pOF\n",
- node);
- drm_of_component_match_add(dev, &match, component_compare_of,
- node);
+ switch (comp_type) {
+ default:
+ break;
+ case MTK_DISP_AAL:
+ case MTK_DISP_CCORR:
+ case MTK_DISP_COLOR:
+ case MTK_DISP_GAMMA:
+ case MTK_DISP_MERGE:
+ case MTK_DISP_OVL:
+ case MTK_DISP_OVL_2L:
+ case MTK_DISP_OVL_ADAPTOR:
+ case MTK_DISP_RDMA:
+ case MTK_DP_INTF:
+ case MTK_DPI:
+ case MTK_DSI:
+ dev_info(dev, "Adding component match for %pOF\n", node);
+ drm_of_component_match_add(dev, &match, component_compare_of, node);
+ break;
}

ret = mtk_ddp_comp_init(node, &private->ddp_comp[comp_id], comp_id);
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
index 78d698ede1bf..7e54d86e25a3 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
@@ -59,7 +59,7 @@ struct mtk_drm_private {
struct device *mmsys_dev;
struct device_node *comp_node[DDP_COMPONENT_DRM_ID_MAX];
struct mtk_ddp_comp ddp_comp[DDP_COMPONENT_DRM_ID_MAX];
- const struct mtk_mmsys_driver_data *data;
+ struct mtk_mmsys_driver_data *data;
struct drm_atomic_state *suspend_state;
unsigned int mbox_index;
struct mtk_drm_private **all_drm_private;
diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index c255559cc56e..e036d9394c23 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -904,9 +904,13 @@ static int mtk_dsi_host_attach(struct mipi_dsi_host *host,
dsi->lanes = device->lanes;
dsi->format = device->format;
dsi->mode_flags = device->mode_flags;
- dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
- if (IS_ERR(dsi->next_bridge))
- return PTR_ERR(dsi->next_bridge);
+ dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
+ if (IS_ERR(dsi->next_bridge)) {
+ /* Old devicetree has only one endpoint */
+ dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
+ if (IS_ERR(dsi->next_bridge))
+ return PTR_ERR(dsi->next_bridge);
+ }

drm_bridge_add(&dsi->bridge);

--
2.45.1


2024-05-22 11:49:15

by Sui Jingfeng

[permalink] [raw]
Subject: Re: [v5,3/3] drm/mediatek: Implement OF graphs support for display paths

Hi,

Looks good to me in overall!

On 5/21/24 15:57, AngeloGioacchino Del Regno wrote:
> It is impossible to add each and every possible DDP path combination
> for each and every possible combination of SoC and board: right now,
> this driver hardcodes configuration for 10 SoCs and this is going to
> grow larger and larger, and with new hacks like the introduction of
> mtk_drm_route which is anyway not enough for all final routes as the
> DSI cannot be connected to MERGE if it's not a dual-DSI, or enabling
> DSC preventively doesn't work if the display doesn't support it, or
> others.
>
> Since practically all display IPs in MediaTek SoCs support being
> interconnected with different instances of other, or the same, IPs
> or with different IPs and in different combinations, the final DDP
> pipeline is effectively a board specific configuration.
>
> Implement OF graphs support to the mediatek-drm drivers, allowing to
> stop hardcoding the paths, and preventing this driver to get a huge
> amount of arrays for each board and SoC combination, also paving the
> way to share the same mtk_mmsys_driver_data between multiple SoCs,
> making it more straightforward to add support for new chips.
>
> Reviewed-by: Alexandre Mergnat <[email protected]>
> Tested-by: Alexandre Mergnat <[email protected]>
> Signed-off-by: AngeloGioacchino Del Regno <[email protected]>
> ---
> drivers/gpu/drm/mediatek/mtk_disp_drv.h | 1 +
> .../gpu/drm/mediatek/mtk_disp_ovl_adaptor.c | 40 ++-
> drivers/gpu/drm/mediatek/mtk_dpi.c | 16 +-
> drivers/gpu/drm/mediatek/mtk_drm_drv.c | 282 ++++++++++++++++--
> drivers/gpu/drm/mediatek/mtk_drm_drv.h | 2 +-
> drivers/gpu/drm/mediatek/mtk_dsi.c | 10 +-
> 6 files changed, 313 insertions(+), 38 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> index 082ac18fe04a..94843974851f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> @@ -108,6 +108,7 @@ size_t mtk_ovl_get_num_formats(struct device *dev);
>
> void mtk_ovl_adaptor_add_comp(struct device *dev, struct mtk_mutex *mutex);
> void mtk_ovl_adaptor_remove_comp(struct device *dev, struct mtk_mutex *mutex);
> +bool mtk_ovl_adaptor_is_comp_present(struct device_node *node);
> void mtk_ovl_adaptor_connect(struct device *dev, struct device *mmsys_dev,
> unsigned int next);
> void mtk_ovl_adaptor_disconnect(struct device *dev, struct device *mmsys_dev,
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> index 02dd7dcdfedb..400519d1ca1f 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> @@ -491,6 +491,38 @@ static int compare_of(struct device *dev, void *data)
> return dev->of_node == data;
> }
>
> +static int ovl_adaptor_of_get_ddp_comp_type(struct device_node *node,
> + enum mtk_ovl_adaptor_comp_type *ctype)
> +{
> + const struct of_device_id *of_id = of_match_node(mtk_ovl_adaptor_comp_dt_ids, node);
> +
> + if (!of_id)
> + return -EINVAL;
> +
> + *ctype = (enum mtk_ovl_adaptor_comp_type)((uintptr_t)of_id->data);
> +
> + return 0;
> +}
> +
> +bool mtk_ovl_adaptor_is_comp_present(struct device_node *node)
> +{
> + enum mtk_ovl_adaptor_comp_type type;
> + int ret;
> +
> + ret = ovl_adaptor_of_get_ddp_comp_type(node, &type);
> + if (ret)
> + return false;
> +
> + if (type >= OVL_ADAPTOR_TYPE_NUM)
> + return false;
> +
> + /*
> + * ETHDR and Padding are used exclusively in OVL Adaptor: if this
> + * component is not one of those, it's likely not an OVL Adaptor path.
> + */
> + return type == OVL_ADAPTOR_TYPE_ETHDR || type == OVL_ADAPTOR_TYPE_PADDING;
> +}
> +
> static int ovl_adaptor_comp_init(struct device *dev, struct component_match **match)
> {
> struct mtk_disp_ovl_adaptor *priv = dev_get_drvdata(dev);
> @@ -500,12 +532,11 @@ static int ovl_adaptor_comp_init(struct device *dev, struct component_match **ma
> parent = dev->parent->parent->of_node->parent;
>
> for_each_child_of_node(parent, node) {
> - const struct of_device_id *of_id;
> enum mtk_ovl_adaptor_comp_type type;
> - int id;
> + int id, ret;
>
> - of_id = of_match_node(mtk_ovl_adaptor_comp_dt_ids, node);
> - if (!of_id)
> + ret = ovl_adaptor_of_get_ddp_comp_type(node, &type);
> + if (ret)
> continue;
>
> if (!of_device_is_available(node)) {
> @@ -514,7 +545,6 @@ static int ovl_adaptor_comp_init(struct device *dev, struct component_match **ma
> continue;
> }
>
> - type = (enum mtk_ovl_adaptor_comp_type)(uintptr_t)of_id->data;
> id = ovl_adaptor_comp_get_id(dev, node, type);
> if (id < 0) {
> dev_warn(dev, "Skipping unknown component %pOF\n",
> diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c
> index bfe8653005db..5c86aa0b75b2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> @@ -705,6 +705,15 @@ static int mtk_dpi_bridge_attach(struct drm_bridge *bridge,
> {
> struct mtk_dpi *dpi = bridge_to_dpi(bridge);
>
> + dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 1, -1);
> + if (IS_ERR(dpi->next_bridge)) {
> + /* Old devicetree has only one endpoint */
> + dpi->next_bridge = devm_drm_of_get_bridge(dpi->dev, dpi->dev->of_node, 0, 0);
> + if (IS_ERR(dpi->next_bridge))
> + return dev_err_probe(dpi->dev, PTR_ERR(dpi->next_bridge),
> + "Failed to get bridge\n");
> + }
> +
> return drm_bridge_attach(bridge->encoder, dpi->next_bridge,
> &dpi->bridge, flags);
> }
> @@ -1055,13 +1064,6 @@ static int mtk_dpi_probe(struct platform_device *pdev)
> if (dpi->irq < 0)
> return dpi->irq;
>
> - dpi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
> - if (IS_ERR(dpi->next_bridge))
> - return dev_err_probe(dev, PTR_ERR(dpi->next_bridge),
> - "Failed to get bridge\n");
> -
> - dev_info(dev, "Found bridge node: %pOF\n", dpi->next_bridge->of_node);
> -
> platform_set_drvdata(pdev, dpi);
>
> dpi->bridge.funcs = &mtk_dpi_bridge_funcs;
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> index b5f605751b0a..ce8f3cc6e853 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c
> @@ -26,6 +26,7 @@
>
> #include "mtk_crtc.h"
> #include "mtk_ddp_comp.h"
> +#include "mtk_disp_drv.h"
> #include "mtk_drm_drv.h"
> #include "mtk_gem.h"
>
> @@ -798,12 +799,226 @@ static const struct of_device_id mtk_ddp_comp_dt_ids[] = {
> { }
> };
>
> +static int mtk_drm_of_get_ddp_comp_type(struct device_node *node, enum mtk_ddp_comp_type *ctype)
> +{
> + const struct of_device_id *of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
> +
> + if (!of_id)
> + return -EINVAL;
> +
> + *ctype = (enum mtk_ddp_comp_type)((uintptr_t)of_id->data);
> +
> + return 0;
> +}
> +
> +static int mtk_drm_of_get_ddp_ep_cid(struct device_node *node,
> + int output_port, enum mtk_crtc_path crtc_path,
> + struct device_node **next, unsigned int *cid)
> +{
> + struct device_node *ep_dev_node, *ep_out;
> + enum mtk_ddp_comp_type comp_type;
> + int ret;
> +
> + ep_out = of_graph_get_endpoint_by_regs(node, output_port, crtc_path);
> + if (!ep_out)
> + return -ENOENT;
> +
> + ep_dev_node = of_graph_get_remote_port_parent(ep_out);
> + if (!ep_dev_node)
> + return -EINVAL;
> +
> + /*
> + * Pass the next node pointer regardless of failures in the later code
> + * so that if this function is called in a loop it will walk through all
> + * of the subsequent endpoints anyway.
> + */
> + *next = ep_dev_node;
> +
> + if (!of_device_is_available(ep_dev_node))
> + return -ENODEV;
> +
> + ret = mtk_drm_of_get_ddp_comp_type(ep_dev_node, &comp_type);
> + if (ret) {
> + if (mtk_ovl_adaptor_is_comp_present(ep_dev_node)) {
> + *cid = (unsigned int)DDP_COMPONENT_DRM_OVL_ADAPTOR;
> + return 0;
> + }
> + return ret;
> + }
> +
> + ret = mtk_ddp_comp_get_id(ep_dev_node, comp_type);
> + if (ret < 0)
> + return ret;
> +
> + /* All ok! Pass the Component ID to the caller. */
> + *cid = (unsigned int)ret;
> +
> + return 0;
> +}
> +
> +/**
> + * mtk_drm_of_ddp_path_build_one - Build a Display HW Pipeline for a CRTC Path
> + * @dev: The mediatek-drm device
> + * @cpath: CRTC Path relative to a VDO or MMSYS
> + * @out_path: Pointer to an array that will contain the new pipeline
> + * @out_path_len: Number of entries in the pipeline array
> + *
> + * MediaTek SoCs can use different DDP hardware pipelines (or paths) depending
> + * on the board-specific desired display configuration; this function walks
> + * through all of the output endpoints starting from a VDO or MMSYS hardware
> + * instance and builds the right pipeline as specified in device trees.
> + *
> + * Return:
> + * * %0 - Display HW Pipeline successfully built and validated
> + * * %-ENOENT - Display pipeline was not specified in device tree
> + * * %-EINVAL - Display pipeline built but validation failed
> + * * %-ENOMEM - Failure to allocate pipeline array to pass to the caller
> + */
> +static int mtk_drm_of_ddp_path_build_one(struct device *dev, enum mtk_crtc_path cpath,
> + const unsigned int **out_path,
> + unsigned int *out_path_len)
> +{
> + struct device_node *next, *prev, *vdo = dev->parent->of_node;
> + unsigned int temp_path[DDP_COMPONENT_DRM_ID_MAX] = { 0 };
> + unsigned int *final_ddp_path;
> + unsigned short int idx = 0;
> + bool ovl_adaptor_comp_added = false;
> + int ret;
> +
> + /* Get the first entry for the temp_path array */
> + ret = mtk_drm_of_get_ddp_ep_cid(vdo, 0, cpath, &next, &temp_path[idx]);
> + if (ret) {
> + if (next && temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
> + dev_err(dev, "Adding OVL Adaptor for %pOF\n", next);
> + ovl_adaptor_comp_added = true;
> + } else {
> + if (next)
> + dev_err(dev, "Invalid component %pOF\n", next);
> + else
> + dev_err(dev, "Cannot find first endpoint for path %d\n", cpath);
> +
> + return ret;
> + }
> + }
> + idx++;
> +
> + /*
> + * Walk through port outputs until we reach the last valid mediatek-drm component.
> + * To be valid, this must end with an "invalid" component that is a display node.
> + */
> + do {
> + prev = next;
> + ret = mtk_drm_of_get_ddp_ep_cid(next, 1, cpath, &next, &temp_path[idx]);
> + of_node_put(prev);
> + if (ret) {
> + of_node_put(next);
> + break;
> + }
> +
> + /*
> + * If this is an OVL adaptor exclusive component and one of those
> + * was already added, don't add another instance of the generic
> + * DDP_COMPONENT_OVL_ADAPTOR, as this is used only to decide whether
> + * to probe that component master driver of which only one instance
> + * is needed and possible.
> + */
> + if (temp_path[idx] == DDP_COMPONENT_DRM_OVL_ADAPTOR) {
> + if (!ovl_adaptor_comp_added)
> + ovl_adaptor_comp_added = true;
> + else
> + idx--;
> + }
> + } while (++idx < DDP_COMPONENT_DRM_ID_MAX);
> +
> + /* If the last entry is not a final display output, the configuration is wrong */
> + switch (temp_path[idx - 1]) {
> + case DDP_COMPONENT_DP_INTF0:
> + case DDP_COMPONENT_DP_INTF1:
> + case DDP_COMPONENT_DPI0:
> + case DDP_COMPONENT_DPI1:
> + case DDP_COMPONENT_DSI0:
> + case DDP_COMPONENT_DSI1:
> + case DDP_COMPONENT_DSI2:
> + case DDP_COMPONENT_DSI3:
> + break;
> + default:
> + dev_err(dev, "Invalid display hw pipeline. Last component: %d (ret=%d)\n",
> + temp_path[idx - 1], ret);
> + return -EINVAL;
> + }
> +
> + final_ddp_path = devm_kmemdup(dev, temp_path, idx * sizeof(temp_path[0]), GFP_KERNEL);
> + if (!final_ddp_path)
> + return -ENOMEM;
> +
> + dev_dbg(dev, "Display HW Pipeline built with %d components.\n", idx);
> +
> + /* Pipeline built! */
> + *out_path = final_ddp_path;
> + *out_path_len = idx;
> +
> + return 0;
> +}
> +
> +static int mtk_drm_of_ddp_path_build(struct device *dev, struct device_node *node,
> + struct mtk_mmsys_driver_data *data)
> +{
> + struct device_node *ep_node;
> + struct of_endpoint of_ep;
> + bool output_present[MAX_CRTC] = { false };
> + int ret;
> +
> + for_each_endpoint_of_node(node, ep_node) {
> + ret = of_graph_parse_endpoint(ep_node, &of_ep);
> + of_node_put(ep_node);
> + if (ret) {
> + dev_err_probe(dev, ret, "Cannot parse endpoint\n");
> + break;
> + }
> +
> + if (of_ep.id >= MAX_CRTC) {
> + ret = dev_err_probe(dev, -EINVAL,
> + "Invalid endpoint%u number\n", of_ep.port);
> + break;
> + }
> +
> + output_present[of_ep.id] = true;
> + }
> +
> + if (ret)
> + return ret;
> +
> + if (output_present[CRTC_MAIN]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_MAIN,
> + &data->main_path, &data->main_len);
> + if (ret)
> + return ret;
> + }
> +
> + if (output_present[CRTC_EXT]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_EXT,
> + &data->ext_path, &data->ext_len);
> + if (ret)
> + return ret;
> + }
> +
> + if (output_present[CRTC_THIRD]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_THIRD,
> + &data->third_path, &data->third_len);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int mtk_drm_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> struct device_node *phandle = dev->parent->of_node;
> const struct of_device_id *of_id;
> struct mtk_drm_private *private;
> + struct mtk_mmsys_driver_data *mtk_drm_data;
> struct device_node *node;
> struct component_match *match = NULL;
> struct platform_device *ovl_adaptor;
> @@ -824,7 +1039,31 @@ static int mtk_drm_probe(struct platform_device *pdev)
> if (!of_id)
> return -ENODEV;
>
> - private->data = of_id->data;
> + mtk_drm_data = (struct mtk_mmsys_driver_data *)of_id->data;
> + if (!mtk_drm_data)
> + return -EINVAL;
> +
> + private->data = kmemdup(mtk_drm_data, sizeof(*mtk_drm_data), GFP_KERNEL);
> + if (!private->data)
> + return -ENOMEM;
> +
> + /* Try to build the display pipeline from devicetree graphs */
> + if (of_graph_is_present(phandle)) {
> + dev_dbg(dev, "Building display pipeline for MMSYS %u\n",
> + mtk_drm_data->mmsys_id);
> + private->data = devm_kmemdup(dev, mtk_drm_data,
> + sizeof(*mtk_drm_data), GFP_KERNEL);
> + if (!private->data)
> + return -ENOMEM;
> +
> + ret = mtk_drm_of_ddp_path_build(dev, phandle, private->data);
> + if (ret)
> + return ret;
> + } else {
> + /* No devicetree graphs support: go with hardcoded paths if present */
> + dev_dbg(dev, "Using hardcoded paths for MMSYS %u\n", mtk_drm_data->mmsys_id);
> + private->data = mtk_drm_data;
> + };
>
> private->all_drm_private = devm_kmalloc_array(dev, private->data->mmsys_dev_num,
> sizeof(*private->all_drm_private),
> @@ -846,12 +1085,11 @@ static int mtk_drm_probe(struct platform_device *pdev)
>
> /* Iterate over sibling DISP function blocks */
> for_each_child_of_node(phandle->parent, node) {
> - const struct of_device_id *of_id;
> enum mtk_ddp_comp_type comp_type;
> int comp_id;
>
> - of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
> - if (!of_id)
> + ret = mtk_drm_of_get_ddp_comp_type(node, &comp_type);
> + if (ret)
> continue;
>
> if (!of_device_is_available(node)) {
> @@ -860,8 +1098,6 @@ static int mtk_drm_probe(struct platform_device *pdev)
> continue;
> }
>
> - comp_type = (enum mtk_ddp_comp_type)(uintptr_t)of_id->data;
> -
> if (comp_type == MTK_DISP_MUTEX) {
> int id;
>
> @@ -890,22 +1126,24 @@ static int mtk_drm_probe(struct platform_device *pdev)
> * blocks have separate component platform drivers and initialize their own
> * DDP component structure. The others are initialized here.
> */
> - if (comp_type == MTK_DISP_AAL ||
> - comp_type == MTK_DISP_CCORR ||
> - comp_type == MTK_DISP_COLOR ||
> - comp_type == MTK_DISP_GAMMA ||
> - comp_type == MTK_DISP_MERGE ||
> - comp_type == MTK_DISP_OVL ||
> - comp_type == MTK_DISP_OVL_2L ||
> - comp_type == MTK_DISP_OVL_ADAPTOR ||
> - comp_type == MTK_DISP_RDMA ||
> - comp_type == MTK_DP_INTF ||
> - comp_type == MTK_DPI ||
> - comp_type == MTK_DSI) {
> - dev_info(dev, "Adding component match for %pOF\n",
> - node);
> - drm_of_component_match_add(dev, &match, component_compare_of,
> - node);
> + switch (comp_type) {
> + default:
> + break;
> + case MTK_DISP_AAL:
> + case MTK_DISP_CCORR:
> + case MTK_DISP_COLOR:
> + case MTK_DISP_GAMMA:
> + case MTK_DISP_MERGE:
> + case MTK_DISP_OVL:
> + case MTK_DISP_OVL_2L:
> + case MTK_DISP_OVL_ADAPTOR:
> + case MTK_DISP_RDMA:
> + case MTK_DP_INTF:
> + case MTK_DPI:
> + case MTK_DSI:
> + dev_info(dev, "Adding component match for %pOF\n", node);
> + drm_of_component_match_add(dev, &match, component_compare_of, node);
> + break;
> }
>
> ret = mtk_ddp_comp_init(node, &private->ddp_comp[comp_id], comp_id);
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.h b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> index 78d698ede1bf..7e54d86e25a3 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.h
> @@ -59,7 +59,7 @@ struct mtk_drm_private {
> struct device *mmsys_dev;
> struct device_node *comp_node[DDP_COMPONENT_DRM_ID_MAX];
> struct mtk_ddp_comp ddp_comp[DDP_COMPONENT_DRM_ID_MAX];
> - const struct mtk_mmsys_driver_data *data;
> + struct mtk_mmsys_driver_data *data;
> struct drm_atomic_state *suspend_state;
> unsigned int mbox_index;
> struct mtk_drm_private **all_drm_private;
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index c255559cc56e..e036d9394c23 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -904,9 +904,13 @@ static int mtk_dsi_host_attach(struct mipi_dsi_host *host,
> dsi->lanes = device->lanes;
> dsi->format = device->format;
> dsi->mode_flags = device->mode_flags;
> - dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
> - if (IS_ERR(dsi->next_bridge))
> - return PTR_ERR(dsi->next_bridge);
> + dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
> + if (IS_ERR(dsi->next_bridge)) {
> + /* Old devicetree has only one endpoint */


devm_drm_of_get_bridge() can return '-EPROBE_DEFER', do you take this
into consideration? if the not bridge is not ready, then we probably
shouldn't find the bridge from another port, right?

I means that even with a good DT, devm_drm_of_get_bridge() still will
fails because of the next bridges is not ready. This may happen if the
kernel module of the next bridge is not loaded yet or other dependencies
not meet yet.

> + dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
> + if (IS_ERR(dsi->next_bridge))
> + return PTR_ERR(dsi->next_bridge);
> + }
>
> drm_bridge_add(&dsi->bridge);
>

--
Best regards
Sui

2024-05-22 11:52:07

by Sui Jingfeng

[permalink] [raw]
Subject: Re: [v5,3/3] drm/mediatek: Implement OF graphs support for display paths

Hi,


On 5/22/24 19:48, Sui Jingfeng wrote:
> if the not bridge is not ready


'not' -> 'next'

2024-05-22 12:14:41

by Sui Jingfeng

[permalink] [raw]
Subject: Re: [v5,3/3] drm/mediatek: Implement OF graphs support for display paths

Hi,


On 5/21/24 15:57, AngeloGioacchino Del Regno wrote:
> +static int mtk_drm_of_get_ddp_comp_type(struct device_node *node, enum mtk_ddp_comp_type *ctype)
> +{
> + const struct of_device_id *of_id = of_match_node(mtk_ddp_comp_dt_ids, node);
> +
> + if (!of_id)
> + return -EINVAL;
> +
> + *ctype = (enum mtk_ddp_comp_type)((uintptr_t)of_id->data);
> +
> + return 0;
> +}
> +
> +static int mtk_drm_of_get_ddp_ep_cid(struct device_node *node,
> + int output_port, enum mtk_crtc_path crtc_path,
> + struct device_node **next, unsigned int *cid)
> +{
> + struct device_node *ep_dev_node, *ep_out;
> + enum mtk_ddp_comp_type comp_type;
> + int ret;
> +
> + ep_out = of_graph_get_endpoint_by_regs(node, output_port, crtc_path);
> + if (!ep_out)
> + return -ENOENT;
> +
> + ep_dev_node = of_graph_get_remote_port_parent(ep_out);

below here, 'ep_out' will not be used anymore.

of_node_put(ep_out);

Maybe we should call it under a error handling tag?
But this is trivial problem.

> + if (!ep_dev_node)
> + return -EINVAL;
> +
> + /*
> + * Pass the next node pointer regardless of failures in the later code
> + * so that if this function is called in a loop it will walk through all
> + * of the subsequent endpoints anyway.
> + */
> + *next = ep_dev_node;
> +
> + if (!of_device_is_available(ep_dev_node))
> + return -ENODEV;
> +
> + ret = mtk_drm_of_get_ddp_comp_type(ep_dev_node, &comp_type);
> + if (ret) {
> + if (mtk_ovl_adaptor_is_comp_present(ep_dev_node)) {
> + *cid = (unsigned int)DDP_COMPONENT_DRM_OVL_ADAPTOR;
> + return 0;
> + }
> + return ret;
> + }
> +
> + ret = mtk_ddp_comp_get_id(ep_dev_node, comp_type);
> + if (ret < 0)
> + return ret;
> +
> + /* All ok! Pass the Component ID to the caller. */
> + *cid = (unsigned int)ret;
> +
> + return 0;
> +}
> +

--
Best regards
Sui Jingfeng


2024-05-22 12:33:54

by Sui Jingfeng

[permalink] [raw]
Subject: Re: [v5,3/3] drm/mediatek: Implement OF graphs support for display paths

Hi,


On 5/21/24 15:57, AngeloGioacchino Del Regno wrote:
> +static int mtk_drm_of_ddp_path_build(struct device *dev, struct device_node *node,
> + struct mtk_mmsys_driver_data *data)
> +{
> + struct device_node *ep_node;
> + struct of_endpoint of_ep;
> + bool output_present[MAX_CRTC] = { false };
> + int ret;
> +
> + for_each_endpoint_of_node(node, ep_node) {
> + ret = of_graph_parse_endpoint(ep_node, &of_ep);
> + of_node_put(ep_node);

There is going to *double* decline the reference counter, as the
__of_get_next_child() will decrease the reference counter for us
on the next iteration.


> + if (ret) {
> + dev_err_probe(dev, ret, "Cannot parse endpoint\n");
> + break;
> + }

Move the 'of_node_put(ep_node)' into brace '{}' here, if we really cares
about the reference count.

> +
> + if (of_ep.id >= MAX_CRTC) {

ditto ?

> + ret = dev_err_probe(dev, -EINVAL,
> + "Invalid endpoint%u number\n", of_ep.port);
> + break;
> + }
> +
> + output_present[of_ep.id] = true;
> + }
> +
> + if (ret)
> + return ret;
> +
> + if (output_present[CRTC_MAIN]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_MAIN,
> + &data->main_path, &data->main_len);
> + if (ret)
> + return ret;
> + }
> +
> + if (output_present[CRTC_EXT]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_EXT,
> + &data->ext_path, &data->ext_len);
> + if (ret)
> + return ret;
> + }
> +
> + if (output_present[CRTC_THIRD]) {
> + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_THIRD,
> + &data->third_path, &data->third_len);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +

--
Best regards
Sui Jingfeng


2024-05-23 10:41:23

by Chen-Yu Tsai

[permalink] [raw]
Subject: Re: [v5,3/3] drm/mediatek: Implement OF graphs support for display paths

On Wed, May 22, 2024 at 8:32 PM Sui Jingfeng <[email protected]> wrote:
>
> Hi,
>
>
> On 5/21/24 15:57, AngeloGioacchino Del Regno wrote:
> > +static int mtk_drm_of_ddp_path_build(struct device *dev, struct device_node *node,
> > + struct mtk_mmsys_driver_data *data)
> > +{
> > + struct device_node *ep_node;
> > + struct of_endpoint of_ep;
> > + bool output_present[MAX_CRTC] = { false };
> > + int ret;
> > +
> > + for_each_endpoint_of_node(node, ep_node) {
> > + ret = of_graph_parse_endpoint(ep_node, &of_ep);
> > + of_node_put(ep_node);
>
> There is going to *double* decline the reference counter, as the
> __of_get_next_child() will decrease the reference counter for us
> on the next iteration.
>
>
> > + if (ret) {
> > + dev_err_probe(dev, ret, "Cannot parse endpoint\n");
> > + break;
> > + }
>
> Move the 'of_node_put(ep_node)' into brace '{}' here, if we really cares
> about the reference count.
>
> > +
> > + if (of_ep.id >= MAX_CRTC) {
>
> ditto ?

Maybe we should just add a scoped version of for_each_endpoint_of_node().

See https://lore.kernel.org/all/[email protected]/

ChenYu

> > + ret = dev_err_probe(dev, -EINVAL,
> > + "Invalid endpoint%u number\n", of_ep.port);
> > + break;
> > + }
> > +
> > + output_present[of_ep.id] = true;
> > + }
> > +
> > + if (ret)
> > + return ret;
> > +
> > + if (output_present[CRTC_MAIN]) {
> > + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_MAIN,
> > + &data->main_path, &data->main_len);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + if (output_present[CRTC_EXT]) {
> > + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_EXT,
> > + &data->ext_path, &data->ext_len);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + if (output_present[CRTC_THIRD]) {
> > + ret = mtk_drm_of_ddp_path_build_one(dev, CRTC_THIRD,
> > + &data->third_path, &data->third_len);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
>
> --
> Best regards
> Sui Jingfeng
>