xref: /freebsd/sys/contrib/device-tree/Bindings/arm/mstar/mstar,l3bridge.yaml (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
1c66ec88fSEmmanuel Vadot# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2c66ec88fSEmmanuel Vadot# Copyright 2020 thingy.jp.
3c66ec88fSEmmanuel Vadot%YAML 1.2
4c66ec88fSEmmanuel Vadot---
5*aa1a8ff2SEmmanuel Vadot$id: http://devicetree.org/schemas/arm/mstar/mstar,l3bridge.yaml#
6*aa1a8ff2SEmmanuel Vadot$schema: http://devicetree.org/meta-schemas/core.yaml#
7c66ec88fSEmmanuel Vadot
8c66ec88fSEmmanuel Vadottitle: MStar/SigmaStar Armv7 SoC l3bridge
9c66ec88fSEmmanuel Vadot
10c66ec88fSEmmanuel Vadotmaintainers:
11c66ec88fSEmmanuel Vadot  - Daniel Palmer <daniel@thingy.jp>
12c66ec88fSEmmanuel Vadot
13c66ec88fSEmmanuel Vadotdescription: |
14c66ec88fSEmmanuel Vadot  MStar/SigmaStar's Armv7 SoCs have a pipeline in the interface
15c66ec88fSEmmanuel Vadot  between the CPU and memory. This means that before DMA capable
16c66ec88fSEmmanuel Vadot  devices are allowed to run the pipeline must be flushed to ensure
17c66ec88fSEmmanuel Vadot  everything is in memory.
18c66ec88fSEmmanuel Vadot
19c66ec88fSEmmanuel Vadot  The l3bridge region contains registers that allow such a flush
20c66ec88fSEmmanuel Vadot  to be triggered.
21c66ec88fSEmmanuel Vadot
22c66ec88fSEmmanuel Vadot  This node is used by the platform code to find where the registers
23c66ec88fSEmmanuel Vadot  are and install a barrier that triggers the required pipeline flush.
24c66ec88fSEmmanuel Vadot
25c66ec88fSEmmanuel Vadotproperties:
26c66ec88fSEmmanuel Vadot  compatible:
27c66ec88fSEmmanuel Vadot    items:
28c66ec88fSEmmanuel Vadot      - const: mstar,l3bridge
29c66ec88fSEmmanuel Vadot
30c66ec88fSEmmanuel Vadot  reg:
31c66ec88fSEmmanuel Vadot    maxItems: 1
32c66ec88fSEmmanuel Vadot
33c66ec88fSEmmanuel Vadotrequired:
34c66ec88fSEmmanuel Vadot  - compatible
35c66ec88fSEmmanuel Vadot  - reg
36c66ec88fSEmmanuel Vadot
37c66ec88fSEmmanuel VadotadditionalProperties: false
38c66ec88fSEmmanuel Vadot
39c66ec88fSEmmanuel Vadotexamples:
40c66ec88fSEmmanuel Vadot  - |
41c66ec88fSEmmanuel Vadot    l3bridge: l3bridge@1f204400 {
42c66ec88fSEmmanuel Vadot        compatible = "mstar,l3bridge";
43c66ec88fSEmmanuel Vadot        reg = <0x1f204400 0x200>;
44c66ec88fSEmmanuel Vadot    };
45