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>

1 files changed, 38 insertions, 0 deletions

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>;
+		};
+	};