[PATCH v4] dt-bindings: iommu: Convert Samsung Exynos IOMMU H/W, System MMU to dt-schema

[Marek Szyprowski <m.szyprowski@samsung.com>]

From: Maciej Falkowski <m.falkowski@samsung.com>

Convert Samsung Exynos IOMMU H/W, System Memory Management Unit
to newer dt-schema format.

Signed-off-by: Maciej Falkowski <m.falkowski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
v4:
- Rename commit message to match common style
- Remove '"pclk", "aclk"' option from clock-names property.
  Some of bindings are incompatible with that and they will be fixed with
  another patch.
- Remove unneeded description of clock-names property.
- Remove type description from power-domains property as it is
  already a common property.
- Rename node names to match generic names,
  specifically: sysmmu -> iommu, gsc -> scaler

- Add include directive in examples to include
  clock macros. This increases readability of the example
  as clock macros do not have to be substituted with numerical values
  which makes examples more self-explanatory and natural.

Best regards,
Maciej Falkowski
---
 .../bindings/iommu/samsung,sysmmu.txt         |  67 -----------
 .../bindings/iommu/samsung,sysmmu.yaml        | 108 ++++++++++++++++++
 2 files changed, 108 insertions(+), 67 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt
 create mode 100644 Documentation/devicetree/bindings/iommu/samsung,sysmmu.yaml

diff --git a/Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt b/Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt
deleted file mode 100644
index 525ec82615a6..000000000000
--- a/Documentation/devicetree/bindings/iommu/samsung,sysmmu.txt
+++ /dev/null
@@ -1,67 +0,0 @@
-Samsung Exynos IOMMU H/W, System MMU (System Memory Management Unit)
-
-Samsung's Exynos architecture contains System MMUs that enables scattered
-physical memory chunks visible as a contiguous region to DMA-capable peripheral
-devices like MFC, FIMC, FIMD, GScaler, FIMC-IS and so forth.
-
-System MMU is an IOMMU and supports identical translation table format to
-ARMv7 translation tables with minimum set of page properties including access
-permissions, shareability and security protection. In addition, System MMU has
-another capabilities like L2 TLB or block-fetch buffers to minimize translation
-latency.
-
-System MMUs are in many to one relation with peripheral devices, i.e. single
-peripheral device might have multiple System MMUs (usually one for each bus
-master), but one System MMU can handle transactions from only one peripheral
-device. The relation between a System MMU and the peripheral device needs to be
-defined in device node of the peripheral device.
-
-MFC in all Exynos SoCs and FIMD, M2M Scalers and G2D in Exynos5420 has 2 System
-MMUs.
-* MFC has one System MMU on its left and right bus.
-* FIMD in Exynos5420 has one System MMU for window 0 and 4, the other system MMU
-  for window 1, 2 and 3.
-* M2M Scalers and G2D in Exynos5420 has one System MMU on the read channel and
-  the other System MMU on the write channel.
-
-For information on assigning System MMU controller to its peripheral devices,
-see generic IOMMU bindings.
-
-Required properties:
-- compatible: Should be "samsung,exynos-sysmmu"
-- reg: A tuple of base address and size of System MMU registers.
-- #iommu-cells: Should be <0>.
-- interrupts: An interrupt specifier for interrupt signal of System MMU,
-	      according to the format defined by a particular interrupt
-	      controller.
-- clock-names: Should be "sysmmu" or a pair of "aclk" and "pclk" to gate
-	       SYSMMU core clocks.
-	       Optional "master" if the clock to the System MMU is gated by
-	       another gate clock other core  (usually main gate clock
-	       of peripheral device this SYSMMU belongs to).
-- clocks: Phandles for respective clocks described by clock-names.
-- power-domains: Required if the System MMU is needed to gate its power.
-	  Please refer to the following document:
-	  Documentation/devicetree/bindings/power/pd-samsung.txt
-
-Examples:
-	gsc_0: gsc@13e00000 {
-		compatible = "samsung,exynos5-gsc";
-		reg = <0x13e00000 0x1000>;
-		interrupts = <0 85 0>;
-		power-domains = <&pd_gsc>;
-		clocks = <&clock CLK_GSCL0>;
-		clock-names = "gscl";
-		iommus = <&sysmmu_gsc0>;
-	};
-
-	sysmmu_gsc0: sysmmu@13e80000 {
-		compatible = "samsung,exynos-sysmmu";
-		reg = <0x13E80000 0x1000>;
-		interrupt-parent = <&combiner>;
-		interrupts = <2 0>;
-		clock-names = "sysmmu", "master";
-		clocks = <&clock CLK_SMMU_GSCL0>, <&clock CLK_GSCL0>;
-		power-domains = <&pd_gsc>;
-		#iommu-cells = <0>;
-	};
diff --git a/Documentation/devicetree/bindings/iommu/samsung,sysmmu.yaml b/Documentation/devicetree/bindings/iommu/samsung,sysmmu.yaml
new file mode 100644
index 000000000000..ecde98da5b72
--- /dev/null
+++ b/Documentation/devicetree/bindings/iommu/samsung,sysmmu.yaml
@@ -0,0 +1,108 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iommu/samsung,sysmmu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung Exynos IOMMU H/W, System MMU (System Memory Management Unit)
+
+maintainers:
+  - Marek Szyprowski <m.szyprowski@samsung.com>
+
+description: |+
+  Samsung's Exynos architecture contains System MMUs that enables scattered
+  physical memory chunks visible as a contiguous region to DMA-capable peripheral
+  devices like MFC, FIMC, FIMD, GScaler, FIMC-IS and so forth.
+
+  System MMU is an IOMMU and supports identical translation table format to
+  ARMv7 translation tables with minimum set of page properties including access
+  permissions, shareability and security protection. In addition, System MMU has
+  another capabilities like L2 TLB or block-fetch buffers to minimize translation
+  latency.
+
+  System MMUs are in many to one relation with peripheral devices, i.e. single
+  peripheral device might have multiple System MMUs (usually one for each bus
+  master), but one System MMU can handle transactions from only one peripheral
+  device. The relation between a System MMU and the peripheral device needs to be
+  defined in device node of the peripheral device.
+
+  MFC in all Exynos SoCs and FIMD, M2M Scalers and G2D in Exynos5420 has 2 System
+  MMUs.
+  * MFC has one System MMU on its left and right bus.
+  * FIMD in Exynos5420 has one System MMU for window 0 and 4, the other system MMU
+    for window 1, 2 and 3.
+  * M2M Scalers and G2D in Exynos5420 has one System MMU on the read channel and
+    the other System MMU on the write channel.
+
+  For information on assigning System MMU controller to its peripheral devices,
+  see generic IOMMU bindings.
+
+properties:
+  compatible:
+    const: samsung,exynos-sysmmu
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    minItems: 1
+    maxItems: 2
+
+  clock-names:
+    oneOf:
+      - items:
+        - const: sysmmu
+      - items:
+        - const: sysmmu
+        - const: master
+      - items:
+        - const: aclk
+        - const: pclk
+
+  "#iommu-cells":
+    const: 0
+
+  power-domains:
+    description: |
+      Required if the System MMU is needed to gate its power.
+      Please refer to the following document:
+      Documentation/devicetree/bindings/power/pd-samsung.txt
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - "#iommu-cells"
+
+examples:
+  - |
+    #include <dt-bindings/clock/exynos5250.h>
+
+    gsc_0: scaler@13e00000 {
+      compatible = "samsung,exynos5-gsc";
+      reg = <0x13e00000 0x1000>;
+      interrupts = <0 85 0>;
+      power-domains = <&pd_gsc>;
+      clocks = <&clock CLK_GSCL0>;
+      clock-names = "gscl";
+      iommus = <&sysmmu_gsc0>;
+    };
+
+    sysmmu_gsc0: iommu@13e80000 {
+      compatible = "samsung,exynos-sysmmu";
+      reg = <0x13E80000 0x1000>;
+      interrupt-parent = <&combiner>;
+      interrupts = <2 0>;
+      clock-names = "sysmmu", "master";
+      clocks = <&clock CLK_SMMU_GSCL0>,
+               <&clock CLK_GSCL0>;
+      power-domains = <&pd_gsc>;
+      #iommu-cells = <0>;
+    };
+
-- 
2.17.1