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+# 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.yaml
+ 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>;
+ };
+