dt-bindings: Consolidate SRAM bindings from all vendors

SRAM bindings for various SoCs, using the mmio-sram genalloc
API, are spread over different places - per SoC vendor. Since all of
these are quite similar (they depend on mmio-sram) move them to a common
place.

Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Kukjin Kim <kgene@kernel.org>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Rob Herring <robh@kernel.org>

5 files changed, 223 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sram/rockchip-pmu-sram.txt b/Documentation/devicetree/bindings/sram/rockchip-pmu-sram.txt
new file mode 100644
index 000000000000..6b42fda306ff
--- /dev/null
+++ b/Documentation/devicetree/bindings/sram/rockchip-pmu-sram.txt
@@ -0,0 +1,16 @@
+Rockchip SRAM for pmu:
+------------------------------
+
+The sram of pmu is used to store the function of resume from maskrom(the 1st
+level loader). This is a common use of the "pmu-sram" because it keeps power
+even in low power states in the system.
+
+Required node properties:
+- compatible : should be "rockchip,rk3288-pmu-sram"
+- reg : physical base address and the size of the registers window
+
+Example:
+	sram@ff720000 {
+		compatible = "rockchip,rk3288-pmu-sram", "mmio-sram";
+		reg = <0xff720000 0x1000>;
+	};
diff --git a/Documentation/devicetree/bindings/sram/rockchip-smp-sram.txt b/Documentation/devicetree/bindings/sram/rockchip-smp-sram.txt
new file mode 100644
index 000000000000..800701ecffca
--- /dev/null
+++ b/Documentation/devicetree/bindings/sram/rockchip-smp-sram.txt
@@ -0,0 +1,30 @@
+Rockchip SRAM for smp bringup:
+------------------------------
+
+Rockchip's smp-capable SoCs use the first part of the sram for the bringup
+of the cores. Once the core gets powered up it executes the code that is
+residing at the very beginning of the sram.
+
+Therefore a reserved section sub-node has to be added to the mmio-sram
+declaration.
+
+Required sub-node properties:
+- compatible : should be "rockchip,rk3066-smp-sram"
+
+The rest of the properties should follow the generic mmio-sram discription
+found in Documentation/devicetree/bindings/sram/sram.txt
+
+Example:
+
+	sram: sram@10080000 {
+		compatible = "mmio-sram";
+		reg = <0x10080000 0x10000>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		smp-sram@10080000 {
+			compatible = "rockchip,rk3066-smp-sram";
+			reg = <0x10080000 0x50>;
+		};
+	};
diff --git a/Documentation/devicetree/bindings/sram/samsung-sram.txt b/Documentation/devicetree/bindings/sram/samsung-sram.txt
new file mode 100644
index 000000000000..6bc474b2b885
--- /dev/null
+++ b/Documentation/devicetree/bindings/sram/samsung-sram.txt
@@ -0,0 +1,38 @@
+Samsung Exynos SYSRAM for SMP bringup:
+------------------------------------
+
+Samsung SMP-capable Exynos SoCs use part of the SYSRAM for the bringup
+of the secondary cores. Once the core gets powered up it executes the
+code that is residing at some specific location of the SYSRAM.
+
+Therefore reserved section sub-nodes have to be added to the mmio-sram
+declaration. These nodes are of two types depending upon secure or
+non-secure execution environment.
+
+Required sub-node properties:
+- compatible : depending upon boot mode, should be
+		"samsung,exynos4210-sysram" : for Secure SYSRAM
+		"samsung,exynos4210-sysram-ns" : for Non-secure SYSRAM
+
+The rest of the properties should follow the generic mmio-sram discription
+found in Documentation/devicetree/bindings/sram/sram.txt
+
+Example:
+
+	sysram@02020000 {
+		compatible = "mmio-sram";
+		reg = <0x02020000 0x54000>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0x02020000 0x54000>;
+
+		smp-sysram@0 {
+			compatible = "samsung,exynos4210-sysram";
+			reg = <0x0 0x1000>;
+		};
+
+		smp-sysram@53000 {
+			compatible = "samsung,exynos4210-sysram-ns";
+			reg = <0x53000 0x1000>;
+		};
+	};
diff --git a/Documentation/devicetree/bindings/sram/sram.txt b/Documentation/devicetree/bindings/sram/sram.txt
new file mode 100644
index 000000000000..42ee9438b771
--- /dev/null
+++ b/Documentation/devicetree/bindings/sram/sram.txt
@@ -0,0 +1,67 @@
+Generic on-chip SRAM
+
+Simple IO memory regions to be managed by the genalloc API.
+
+Required properties:
+
+- compatible : mmio-sram
+
+- reg : SRAM iomem address range
+
+Reserving sram areas:
+---------------------
+
+Each child of the sram node specifies a region of reserved memory. Each
+child node should use a 'reg' property to specify a specific range of
+reserved memory.
+
+Following the generic-names recommended practice, node names should
+reflect the purpose of the node. Unit address (@<address>) should be
+appended to the name.
+
+Required properties in the sram node:
+
+- #address-cells, #size-cells : should use the same values as the root node
+- ranges : standard definition, should translate from local addresses
+           within the sram to bus addresses
+
+Required properties in the area nodes:
+
+- reg : iomem address range, relative to the SRAM range
+
+Optional properties in the area nodes:
+
+- compatible : standard definition, should contain a vendor specific string
+               in the form <vendor>,[<device>-]<usage>
+- pool : indicates that the particular reserved SRAM area is addressable
+         and in use by another device or devices
+- export : indicates that the reserved SRAM area may be accessed outside
+           of the kernel, e.g. by bootloader or userspace
+- label : the name for the reserved partition, if omitted, the label
+          is taken from the node name excluding the unit address.
+
+Example:
+
+sram: sram@5c000000 {
+	compatible = "mmio-sram";
+	reg = <0x5c000000 0x40000>; /* 256 KiB SRAM at address 0x5c000000 */
+
+	#adress-cells = <1>;
+	#size-cells = <1>;
+	ranges = <0 0x5c000000 0x40000>;
+
+	smp-sram@100 {
+		compatible = "socvendor,smp-sram";
+		reg = <0x100 0x50>;
+	};
+
+	device-sram@1000 {
+		reg = <0x1000 0x1000>;
+		pool;
+	};
+
+	exported@20000 {
+		reg = <0x20000 0x20000>;
+		export;
+	};
+};
diff --git a/Documentation/devicetree/bindings/sram/sunxi-sram.txt b/Documentation/devicetree/bindings/sram/sunxi-sram.txt
new file mode 100644
index 000000000000..8d5665468fe7
--- /dev/null
+++ b/Documentation/devicetree/bindings/sram/sunxi-sram.txt
@@ -0,0 +1,72 @@
+Allwinnner SoC SRAM controllers
+-----------------------------------------------------
+
+The SRAM controller found on most Allwinner devices is represented by
+a regular node for the SRAM controller itself, with sub-nodes
+reprensenting the SRAM handled by the SRAM controller.
+
+Controller Node
+---------------
+
+Required properties:
+- compatible : "allwinner,sun4i-a10-sram-controller"
+- reg : sram controller register offset + length
+
+SRAM nodes
+----------
+
+Each SRAM is described using the mmio-sram bindings documented in
+Documentation/devicetree/bindings/sram/sram.txt
+
+Each SRAM will have SRAM sections that are going to be handled by the
+SRAM controller as subnodes. These sections are represented following
+once again the representation described in the mmio-sram binding.
+
+The valid sections compatible are:
+    - allwinner,sun4i-a10-sram-a3-a4
+    - allwinner,sun4i-a10-sram-d
+
+Devices using SRAM sections
+---------------------------
+
+Some devices need to request to the SRAM controller to map an SRAM for
+their exclusive use.
+
+The relationship between such a device and an SRAM section is
+expressed through the allwinner,sram property, that will take a
+phandle and an argument.
+
+This valid values for this argument are:
+  - 0: CPU
+  - 1: Device
+
+Example
+-------
+sram-controller@01c00000 {
+	compatible = "allwinner,sun4i-a10-sram-controller";
+	reg = <0x01c00000 0x30>;
+	#address-cells = <1>;
+	#size-cells = <1>;
+	ranges;
+
+	sram_a: sram@00000000 {
+		compatible = "mmio-sram";
+		reg = <0x00000000 0xc000>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0x00000000 0xc000>;
+
+		emac_sram: sram-section@8000 {
+			compatible = "allwinner,sun4i-a10-sram-a3-a4";
+			reg = <0x8000 0x4000>;
+			status = "disabled";
+		};
+	};
+};
+
+emac: ethernet@01c0b000 {
+	compatible = "allwinner,sun4i-a10-emac";
+	...
+
+	allwinner,sram = <&emac_sram 1>;
+};