The TRNG block in Exynos850 is pretty much the same as in Exynos5250,
but there are two clocks that has to be controlled to make it work:
1. Functional (operating) clock: called ACLK in Exynos850, the same as
"secss" clock in Exynos5250
2. Interface (bus) clock: called PCLK in Exynos850. It has to be
enabled in order to access TRNG registers
Document Exynos850 compatible and the related clock changes, and provide
a corresponding example for Exynos850 TRNG node with ACLK and PCLK
clocks.
Signed-off-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
---
.../bindings/rng/samsung,exynos-trng.yaml | 49 +++++++++++++++++--
1 file changed, 45 insertions(+), 4 deletions(-)
diff --git a/Documentation/devicetree/bindings/rng/samsung,exynos-trng.yaml b/Documentation/devicetree/bindings/rng/samsung,exynos-trng.yaml
index 99c382d25c11..e57310fa89c7 100644
--- a/Documentation/devicetree/bindings/rng/samsung,exynos-trng.yaml
+++ b/Documentation/devicetree/bindings/rng/samsung,exynos-trng.yaml
@@ -12,14 +12,17 @@ maintainers:
properties:
compatible:
- const: samsung,exynos5250-trng
+ enum:
+ - samsung,exynos5250-trng
+ - samsung,exynos850-trng
clocks:
- maxItems: 1
+ minItems: 1
+ maxItems: 2
clock-names:
- items:
- - const: secss
+ minItems: 1
+ maxItems: 2
reg:
maxItems: 1
@@ -30,6 +33,35 @@ required:
- clock-names
- reg
+allOf:
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: samsung,exynos850-trng
+
+ then:
+ properties:
+ clocks:
+ items:
+ - description: SSS (Security Sub System) operating clock
+ - description: SSS (Security Sub System) bus clock
+
+ clock-names:
+ items:
+ - const: secss
+ - const: pclk
+
+ else:
+ properties:
+ clocks:
+ items:
+ - description: SSS (Security Sub System) operating clock
+
+ clock-names:
+ items:
+ - const: secss
+
additionalProperties: false
examples:
@@ -42,3 +74,12 @@ examples:
clocks = <&clock CLK_SSS>;
clock-names = "secss";
};
+ - |
+ #include <dt-bindings/clock/exynos850.h>
+
+ rng@12081400 {
+ compatible = "samsung,exynos850-trng";
+ reg = <0x12081400 0x100>;
+ clocks = <&cmu_core CLK_GOUT_SSS_ACLK>, <&cmu_core CLK_GOUT_SSS_PCLK>;
+ clock-names = "secss", "pclk";
+ };
--
2.39.2
