Add TI syscon reset controller binding. This will hook to the reset framework and use syscon/regmap to set reset bits. This allows reset control of individual SoC subsytems and devices with memory-mapped reset registers in a common register memory space.
Signed-off-by: Andrew F. Davis <[email protected]> [[email protected]: revise the binding format] Signed-off-by: Suman Anna <[email protected]> --- .../devicetree/bindings/reset/ti-syscon-reset.txt | 87 ++++++++++++++++++++++ include/dt-bindings/reset/ti-syscon.h | 30 ++++++++ 2 files changed, 117 insertions(+) create mode 100644 Documentation/devicetree/bindings/reset/ti-syscon-reset.txt create mode 100644 include/dt-bindings/reset/ti-syscon.h diff --git a/Documentation/devicetree/bindings/reset/ti-syscon-reset.txt b/Documentation/devicetree/bindings/reset/ti-syscon-reset.txt new file mode 100644 index 0000000..5a0b86c --- /dev/null +++ b/Documentation/devicetree/bindings/reset/ti-syscon-reset.txt @@ -0,0 +1,87 @@ +TI SysCon Reset Controller +======================= + +Almost all SoCs have hardware modules that require reset control in addition +to clock and power control for their functionality. The reset control is +typically provided by means of memory-mapped I/O registers. These registers are +sometimes a part of a larger register space region implementing various +functionalities. This register range is best represented as a syscon node to +allow multiple entities to access their relevant registers in the common +register space. + +A SysCon Reset Controller node defines a device that uses a syscon node +and provides reset management functionality for various hardware modules +present on the SoC. + +SysCon Reset Controller Node +============================ +Each of the reset provider/controller nodes should be a child of a syscon +node and have the following properties. + +Required properties: +-------------------- + - compatible : Should be, + "ti,k2e-pscrst" + "ti,k2l-pscrst" + "ti,k2hk-pscrst" + "syscon-reset" + - #reset-cells : Should be 1. Please see the reset consumer node below + for usage details + - ti,reset-bits : Contains the reset control register information + Should contain 5 cells for each reset exposed to + consumers, defined as: + Cell #1 : register offset of the reset control + register from the syscon register base + Cell #2 : bit shift value for the reset in the + respective reset control register + Cell #3 : register offset of the reset status + register from the syscon register base + Cell #4 : bit shift value for the reset in the + respective reset status register + Cell #5 : Flags used to control reset behavior, + availible flags defined in the DT include + file <dt-bindings/reset/ti-syscon.h> + +SysCon Reset Consumer Nodes +=========================== +Each of the reset consumer nodes should have the following properties, +in addition to their own properties. + +Required properties: +-------------------- + - resets : A phandle to the reset controller node and a phandle to a + reset specifier node as defined above. + +Please also refer to Documentation/devicetree/bindings/reset/reset.txt for +common reset controller usage by consumers. + +Example: +-------- +The following example demonstrates a syscon node, the reset controller node +using the syscon node, and a consumer (a DSP device) on the TI Keystone 2 +Edison SoC. + +/ { + soc { + psc: power-sleep-controller@02350000 { + compatible = "syscon", "simple-mfd"; + reg = <0x02350000 0x1000>; + + pscrst: psc-reset { + compatible = "ti,k2e-pscrst", "syscon-reset"; + #reset-cells = <1>; + + ti,reset-bits = < + 0xa3c 8 0x83c 8 RESET_ASSERT_CLEAR /* 0: pcrst-dsp0 */ + 0xa40 5 0 0 RESET_TRIGGER_SET /* 1: pcrst-example */ + >; + }; + }; + + dsp0: dsp0 { + ... + resets = <&pscrst 0>; + ... + }; + }; +}; diff --git a/include/dt-bindings/reset/ti-syscon.h b/include/dt-bindings/reset/ti-syscon.h new file mode 100644 index 0000000..fedcfb7 --- /dev/null +++ b/include/dt-bindings/reset/ti-syscon.h @@ -0,0 +1,30 @@ +/* + * TI Syscon Reset definitions + * + * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#ifndef __DT_BINDINGS_RESET_TI_SYSCON_H__ +#define __DT_BINDINGS_RESET_TI_SYSCON_H__ + +/* The reset is asserted by setting (vs clearing) the described bit */ +#define RESET_SET (1 << 0) +/* This reset does not have a readable status bit */ +#define RESET_TRIGGER (1 << 1) + +#define RESET_ASSERT_CLEAR 0 +#define RESET_ASSERT_SET RESET_SET +#define RESET_TRIGGER_CLEAR RESET_TRIGGER +#define RESET_TRIGGER_SET (RESET_TRIGGER | RESET_SET) + +#endif -- 2.9.0
