There is a single register provided by the SoC system controller, which can be used to tune the L2-cache RAM up. It only provides a way to change the L2-RAM access latencies. So aside from "be,bt1-l2-ctl" compatible string the device node can be optionally equipped with the properties of Tag/Data/WS latencies. Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx> Cc: Paul Burton <paulburton@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: Olof Johansson <olof@xxxxxxxxx> Cc: Boris Brezillon <bbrezillon@xxxxxxxxxx> Cc: Paul Cercueil <paul@xxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Cc: linux-mips@xxxxxxxxxxxxxxx Cc: soc@xxxxxxxxxx --- Changelog v2: - Move driver to the memory subsystem. - Use dual GPL/BSD license. - Use single lined copyright header. - Move "allOf" restrictions to the root level of the properties. - Discard syscon compatible string and reg property. - The DT node is supposed to be a child of the Baikal-T1 system controller node. --- .../memory-controllers/baikal,bt1-l2-ctl.yaml | 59 +++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 Documentation/devicetree/bindings/memory-controllers/baikal,bt1-l2-ctl.yaml diff --git a/Documentation/devicetree/bindings/memory-controllers/baikal,bt1-l2-ctl.yaml b/Documentation/devicetree/bindings/memory-controllers/baikal,bt1-l2-ctl.yaml new file mode 100644 index 000000000000..263f0cdab4e6 --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/baikal,bt1-l2-ctl.yaml @@ -0,0 +1,59 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +# Copyright (C) 2020 BAIKAL ELECTRONICS, JSC +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/memory-controllers/baikal,bt1-l2-ctl.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Baikal-T1 L2-cache Control Block + +maintainers: + - Serge Semin <fancer.lancer@xxxxxxxxx> + +description: | + By means of the System Controller Baikal-T1 SoC exposes a few settings to + tune the MIPS P5600 CM2 L2 cache performance up. In particular it's possible + to change the Tag, Data and Way-select RAM access latencies. Baikal-T1 + L2-cache controller block is responsible for the tuning. Its DT node is + supposed to be a child of the system controller. + +properties: + compatible: + const: baikal,bt1-l2-ctl + + baikal,l2-ws-latency: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Cycles of latency for Way-select RAM accesses + default: 0 + minimum: 0 + maximum: 3 + + baikal,l2-tag-latency: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Cycles of latency for Tag RAM accesses + default: 0 + minimum: 0 + maximum: 3 + + baikal,l2-data-latency: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Cycles of latency for Data RAM accesses + default: 1 + minimum: 0 + maximum: 3 + +additionalProperties: false + +required: + - compatible + +examples: + - | + l2_ctl { + compatible = "baikal,bt1-l2-ctl"; + + baikal,l2-ws-latency = <0>; + baikal,l2-tag-latency = <0>; + baikal,l2-data-latency = <1>; + }; +... -- 2.25.1
