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

Alim Akhtar alim.akhtar at samsung.com
Thu Oct 27 03:39:55 PDT 2022


Hi Aakarsh
Thanks for the patch.

>-----Original Message-----
>From: aakarsh jain [mailto:aakarsh.jain at samsung.com]
>Sent: Tuesday, October 11, 2022 5:55 PM
>To: linux-arm-kernel at lists.infradead.org; linux-media at vger.kernel.org; linux-
>kernel at vger.kernel.org; devicetree at vger.kernel.org
>Cc: m.szyprowski at samsung.com; andrzej.hajda at intel.com;
>mchehab at kernel.org; hverkuil-cisco at xs4all.nl;
>ezequiel at vanguardiasur.com.ar; jernej.skrabec at gmail.com;
>benjamin.gaignard at collabora.com; stanimir.varbanov at linaro.org;
>dillon.minfei at gmail.com; david.plowman at raspberrypi.com;
>mark.rutland at arm.com; robh+dt at kernel.org; krzk+dt at kernel.org;
>andi at etezian.org; alim.akhtar at samsung.com; aswani.reddy at samsung.com;
>pankaj.dubey at samsung.com; linux-fsd at tesla.com; smitha.t at samsung.com;
>aakarsh.jain at samsung.com
>Subject: [Patch v3 01/15] dt-bindings: media: s5p-mfc: Add new DT schema for
>MFC
>
>From: Smitha T Murthy <smitha.t at samsung.com>
>
>Convert DT schema for s5p-mfc in yaml format
>
>Cc: linux-fsd at tesla.com
>Signed-off-by: Smitha T Murthy <smitha.t at samsung.com>
>Signed-off-by: Aakarsh Jain <aakarsh.jain at samsung.com>
>---
> .../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 at 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 at 51000000 {
>-		compatible = "shared-dma-pool";
>-		no-map;
>-		reg = <0x51000000 0x800000>;
>-	};
>-
>-	mfc_right: region at 43000000 {
>-		compatible = "shared-dma-pool";
>-		no-map;
>-		reg = <0x43000000 0x800000>;
>-	};
>-};
>-
>-Board specific DT entry:
>-
>-codec at 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 at samsung.com>
>+  - Smitha T Murthy <smitha.t at samsung.com>
>+  - Aakarsh Jain <aakarsh.jain at samsung.com>
>+
>+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 at 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






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