RE: [Patch v3 01/15] dt-bindings: media: s5p-mfc: Add new DT schema for MFC

From: Alim Akhtar
Date: Thu Oct 27 2022 - 06:40:27 EST


Hi Aakarsh
Thanks for the patch.

>-----Original Message-----
>From: aakarsh jain [mailto:aakarsh.jain@xxxxxxxxxxx]
>Sent: Tuesday, October 11, 2022 5:55 PM
>To: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-media@xxxxxxxxxxxxxxx; linux-
>kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx
>Cc: m.szyprowski@xxxxxxxxxxx; andrzej.hajda@xxxxxxxxx;
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>Subject: [Patch v3 01/15] dt-bindings: media: s5p-mfc: Add new DT schema for
>MFC
>
>From: Smitha T Murthy <smitha.t@xxxxxxxxxxx>
>
>Convert DT schema for s5p-mfc in yaml format
>
>Cc: linux-fsd@xxxxxxxxx
>Signed-off-by: Smitha T Murthy <smitha.t@xxxxxxxxxxx>
>Signed-off-by: Aakarsh Jain <aakarsh.jain@xxxxxxxxxxx>
>---
> .../devicetree/bindings/media/s5p-mfc.txt | 75 --------
> .../bindings/media/samsung,s5p-mfc.yaml | 163 ++++++++++++++++++
> 2 files changed, 163 insertions(+), 75 deletions(-) create mode 100644
>Documentation/devicetree/bindings/media/samsung,s5p-mfc.yaml
>
>diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt
>b/Documentation/devicetree/bindings/media/s5p-mfc.txt
>index aa54c8159d9f..8b137891791f 100644
>--- a/Documentation/devicetree/bindings/media/s5p-mfc.txt
>+++ b/Documentation/devicetree/bindings/media/s5p-mfc.txt
>@@ -1,76 +1 @@
>-* Samsung Multi Format Codec (MFC)
>
>-Multi Format Codec (MFC) is the IP present in Samsung SoCs which -supports
>high resolution decoding and encoding functionalities.
>-The MFC device driver is a v4l2 driver which can encode/decode -video
>raw/elementary streams and has support for all popular -video codecs.
>-
>-Required properties:
>- - compatible : value should be either one among the following
>- (a) "samsung,mfc-v5" for MFC v5 present in Exynos4 SoCs
>- (b) "samsung,mfc-v6" for MFC v6 present in Exynos5 SoCs
>- (c) "samsung,mfc-v7" for MFC v7 present in Exynos5420 SoC
>- (d) "samsung,mfc-v8" for MFC v8 present in Exynos5800 SoC
>- (e) "samsung,exynos5433-mfc" for MFC v8 present in Exynos5433 SoC
>- (f) "samsung,mfc-v10" for MFC v10 present in Exynos7880 SoC
>-
>- - reg : Physical base address of the IP registers and length of memory
>- mapped region.
>-
>- - interrupts : MFC interrupt number to the CPU.
>- - clocks : from common clock binding: handle to mfc clock.
>- - clock-names : from common clock binding: must contain "mfc",
>- corresponding to entry in the clocks property.
>-
>-Optional properties:
>- - power-domains : power-domain property defined with a phandle
>- to respective power domain.
>- - memory-region : from reserved memory binding: phandles to two
>reserved
>- memory regions, first is for "left" mfc memory bus interfaces,
>- second if for the "right" mfc memory bus, used when no SYSMMU
>- support is available; used only by MFC v5 present in Exynos4 SoCs
>-
>-Obsolete properties:
>- - samsung,mfc-r, samsung,mfc-l : support removed, please use memory-
>region
>- property instead
>-
>-
>-Example:
>-SoC specific DT entry:
>-
>-mfc: codec@13400000 {
>- compatible = "samsung,mfc-v5";
>- reg = <0x13400000 0x10000>;
>- interrupts = <0 94 0>;
>- power-domains = <&pd_mfc>;
>- clocks = <&clock 273>;
>- clock-names = "mfc";
>-};
>-
>-Reserved memory specific DT entry for given board (see reserved memory
>binding -for more information):
>-
>-reserved-memory {
>- #address-cells = <1>;
>- #size-cells = <1>;
>- ranges;
>-
>- mfc_left: region@51000000 {
>- compatible = "shared-dma-pool";
>- no-map;
>- reg = <0x51000000 0x800000>;
>- };
>-
>- mfc_right: region@43000000 {
>- compatible = "shared-dma-pool";
>- no-map;
>- reg = <0x43000000 0x800000>;
>- };
>-};
>-
>-Board specific DT entry:
>-
>-codec@13400000 {
>- memory-region = <&mfc_left>, <&mfc_right>;
>-};
>diff --git a/Documentation/devicetree/bindings/media/samsung,s5p-
>mfc.yaml b/Documentation/devicetree/bindings/media/samsung,s5p-
>mfc.yaml
>new file mode 100644
>index 000000000000..ad61b509846f
>--- /dev/null
>+++ b/Documentation/devicetree/bindings/media/samsung,s5p-mfc.yaml
>@@ -0,0 +1,163 @@
>+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause %YAML 1.2
>+---
>+$id: http://devicetree.org/schemas/media/samsung,s5p-mfc.yaml#
>+$schema: http://devicetree.org/meta-schemas/core.yaml#
>+
>+title: Samsung Exynos Multi Format Codec (MFC)
>+
>+maintainers:
>+ - Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>+ - Smitha T Murthy <smitha.t@xxxxxxxxxxx>
>+ - Aakarsh Jain <aakarsh.jain@xxxxxxxxxxx>
>+
>+description:
>+ Multi Format Codec (MFC) is the IP present in Samsung SoCs which
>+ supports high resolution decoding and encoding functionalities.
>+
>+properties:
>+ compatible:
>+ enum:
>+ - samsung,mfc-v5 # Exynos4
>+ - samsung,mfc-v6 # Exynos5
>+ - samsung,mfc-v7 # Exynos5420
>+ - samsung,mfc-v8 # Exynos5800
>+ - samsung,exynos5433-mfc # Exynos5433
>+ - samsung,mfc-v10 # Exynos7880
>+
>+ reg:
>+ maxItems: 1
>+
>+ clocks:
>+ minItems: 1
>+ maxItems: 3
>+
>+ clock-names:
>+ minItems: 1
>+ maxItems: 3
>+
>+ interrupts:
>+ maxItems: 1
>+
>+ iommus:
>+ maxItems: 2
>+
>+ iommu-names:
>+ maxItems: 2
>+
>+ power-domains:
>+ maxItems: 1
>+
>+ memory-region:
>+ maxItems: 1
>+
>+required:
>+ - compatible
>+ - reg
>+ - clocks
>+ - clock-names
>+ - interrupts
>+
>+allOf:
>+ - if:
>+ properties:
>+ compatible:
>+ contains:
>+ enum:
>+ - samsung,mfc-v6
>+ - samsung,mfc-v7
>+ - samsung,mfc-v8
>+ - tesla,fsd-mfc
You have not introduce "tesla,fsd-mfc" compatible yet, so this should be part of the patch which adds fsd-mfc compatible

>+ then:
>+ properties:
>+ clocks:
>+ maxItems: 1
>+ clock-names:
>+ items:
>+ - const: mfc
>+
>+ - if:
>+ properties:
>+ compatible:
>+ contains:
>+ enum:
>+ - samsung,mfc-v5
>+ then:
>+ properties:
>+ clocks:
>+ minItems: 2
>+ maxItems: 2
>+ clock-names:
>+ items:
>+ - const: mfc
>+ - const: sclk_mfc
>+
>+ - if:
>+ properties:
>+ compatible:
>+ contains:
>+ enum:
>+ - samsung,exynos5433-mfc
>+ then:
>+ properties:
>+ clocks:
>+ minItems: 3
>+ maxItems: 3
>+ clock-names:
>+ items:
>+ - const: pclk
>+ - const: aclk
>+ - const: aclk_xiu
>+
>+ - if:
>+ properties:
>+ compatible:
>+ contains:
>+ enum:
>+ - samsung,mfc-v5
>+ - samsung,mfc-v6
>+ - samsung,mfc-v7
>+ - samsung,mfc-v8
>+ - samsung,exynos5433-mfc
>+
>+ then:
>+ properties:
>+ iommus:
>+ minItems: 2
>+ maxItems: 2
>+ iommu-names:
>+ items:
>+ - const: left
>+ - const: right
>+
>+ - if:
>+ properties:
>+ compatible:
>+ contains:
>+ enum:
>+ - tesla,fsd-mfc

Same comments as above.

My suggestion, first just convert the current s5p-mfc.txt to yaml format and then add fsd-mfc support.
That way it will be easy for reviewer to understand the changes.

While reviewing and code walk through, I also noticed that exynos3250.dtsi and exynos5420.dtsi
are using same compatible as "samsung,mfc-v7" but there "clocks" property is different. That doesn't look correct.
This will cause issues when you convert s5p-mfc.txt to schema format.
I don’t know why that was done that way, but surely this need to be _fixed_ first as h/w itself are different.

So my suggestion is to fix exynos3250.dtsi and exynos5420.dtsi compatible and mfc driver for it first (as a separate patch series).
You can use the same approach what was done for mfc-v8 and mfc-v8-5433.


>+ then:
>+ properties:
>+ memory-region:
>+ maxItems: 1
>+
>+additionalProperties: false
>+
>+examples:
>+ - |
>+ #include <dt-bindings/clock/exynos4.h>
>+ #include <dt-bindings/clock/exynos-audss-clk.h>
>+ #include <dt-bindings/interrupt-controller/arm-gic.h>
>+ #include <dt-bindings/interrupt-controller/irq.h>
>+
>+ codec@13400000 {
>+ compatible = "samsung,mfc-v5";
>+ reg = <0x13400000 0x10000>;
>+ interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>;
>+ power-domains = <&pd_mfc>;
>+ clocks = <&clock CLK_MFC>, <&clock CLK_SCLK_MFC>;
>+ clock-names = "mfc", "sclk_mfc";
>+ iommus = <&sysmmu_mfc_l>, <&sysmmu_mfc_r>;
>+ iommu-names = "left", "right";
>+
>+ };
>--
>2.17.1