[PATCH v5 1/2] dt-bindings: Documentation for qcom, llcc

From: Rishabh Bhatnagar
Date: Mon Apr 23 2018 - 19:11:25 EST


Documentation for last level cache controller device tree bindings,
client bindings usage examples.

Signed-off-by: Channagoud Kadabi <ckadabi@xxxxxxxxxxxxxx>
Signed-off-by: Rishabh Bhatnagar <rishabhb@xxxxxxxxxxxxxx>
---
.../devicetree/bindings/arm/msm/qcom,llcc.txt | 60 ++++++++++++++++++++++
1 file changed, 60 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,llcc.txt

diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,llcc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,llcc.txt
new file mode 100644
index 0000000..c30d433
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/msm/qcom,llcc.txt
@@ -0,0 +1,60 @@
+== Introduction==
+
+LLCC (Last Level Cache Controller) provides last level of cache memory in SOC,
+that can be shared by multiple clients. Clients here are different cores in the
+SOC, the idea is to minimize the local caches at the clients and migrate to
+common pool of memory. Cache memory is divided into partitions called slices
+which are assigned to clients. Clients can query the slice details, activate
+and deactivate them.
+
+Properties:
+- compatible:
+ Usage: required
+ Value type: <string>
+ Definition: must be "qcom,sdm845-llcc"
+
+- reg:
+ Usage: required
+ Value Type: <prop-encoded-array>
+ Definition: Start address and the range of the LLCC registers.
+
+- #cache-cells:
+ Usage: required
+ Value Type: <u32>
+ Definition: Number of cache cells, must be 1
+
+- max-slices:
+ usage: required
+ Value Type: <u32>
+ Definition: Number of cache slices supported by hardware
+
+Example:
+
+ llcc: qcom,llcc@1100000 {
+ compatible = "qcom,sdm845-llcc";
+ reg = <0x1100000 0x250000>;
+ #cache-cells = <1>;
+ max-slices = <32>;
+ };
+
+== Client ==
+
+Properties:
+- cache-slice-names:
+Usage: required
+ Value type: <stringlist>
+ Definition: A set of names that identify the usecase names of a
+ client that uses cache slice. These strings are
+ used to look up the cache slice entries by name.
+
+- cache-slices:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: The tuple has phandle to llcc device as the first
+ argument and the second argument is the usecase
+ id of the client.
+For Example:
+ venus {
+ cache-slice-names = "vidsc0", "vidsc1";
+ cache-slices = <&llcc VIDSC0_ID>, <&llcc VIDSC1_ID>;
+ };
--
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