Re: [PATCH 1/4] dt-bindings: reset: Add PDC reset binding for SDM845 SoCs

From: Philipp Zabel
Date: Tue Jul 31 2018 - 04:42:33 EST


Hi Sibi,

On Fri, 2018-07-27 at 20:58 +0530, Sibi Sankar wrote:
> Add SDM845 PDC (Power Domain Controller) reset controller binding
>
> Signed-off-by: Sibi Sankar <sibis@xxxxxxxxxxxxxx>
> ---
> .../bindings/reset/qcom,pdc-reset.txt | 52 +++++++++++++++++++
> include/dt-bindings/reset/qcom,sdm845-pdc.h | 20 +++++++
> 2 files changed, 72 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/reset/qcom,pdc-reset.txt
> create mode 100644 include/dt-bindings/reset/qcom,sdm845-pdc.h
>
> diff --git a/Documentation/devicetree/bindings/reset/qcom,pdc-reset.txt b/Documentation/devicetree/bindings/reset/qcom,pdc-reset.txt
> new file mode 100644
> index 000000000000..85e159962e08
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/qcom,pdc-reset.txt
> @@ -0,0 +1,52 @@
> +PDC Reset Controller
> +======================================
> +
> +This binding describes a reset-controller found on PDC-Global(Power Domain
> +Controller) block for Qualcomm Technologies Inc SDM845 SoCs.
> +
> +Required properties:
> +- compatible:
> + Usage: required
> + Value type: <string>
> + Definition: must be:
> + "qcom,sdm845-pdc-global"
> +
> +- reg:
> + Usage: required
> + Value type: <prop-encoded-array>
> + Definition: must specify the base address and size of the register
> + space.
> +
> +- #reset-cells:
> + Usage: required
> + Value type: <uint>
> + Definition: must be 1; cell entry represents the reset index.
> +
> +Example:
> +
> +pdc_reset: reset-controller@b2e0000 {

Is this really just a reset controller?

The name makes it sound like a driver binding to this should also
provide pm_genpd and the binding should probably call this a power-
controller: Documentation/devicetree/bindings/power/power_domain.txt.

> + compatible = "qcom,sdm845-pdc-global";
> + reg = <0xb2e0000 0x20000>;

This looks like this is the register space of the complete PDC, not just
the reset register?

> + #reset-cells = <1>;
> +};
> +
> +PDC reset clients
> +======================================
> +
> +Device nodes that need access to reset lines should
> +specify them as a reset phandle in their corresponding node as
> +specified in reset.txt.
> +
> +For list of all valid reset indicies see
> +<dt-bindings/reset/qcom,sdm845-pdc.h>
> +
> +Example:
> +
> +modem-pil@4080000 {
> + ...
> +
> + resets = <&pdc_reset PDC_MODEM_SYNC_RESET>;
> + reset-names = "pdc_restart";
> +
> + ...
> +};
> diff --git a/include/dt-bindings/reset/qcom,sdm845-pdc.h b/include/dt-bindings/reset/qcom,sdm845-pdc.h
> new file mode 100644
> index 000000000000..53c37f9c319a
> --- /dev/null
> +++ b/include/dt-bindings/reset/qcom,sdm845-pdc.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2018 The Linux Foundation. All rights reserved.
> + */
> +
> +#ifndef _DT_BINDINGS_RESET_PDC_SDM_845_H
> +#define _DT_BINDINGS_RESET_PDC_SDM_845_H
> +
> +#define PDC_APPS_SYNC_RESET 0
> +#define PDC_SP_SYNC_RESET 1
> +#define PDC_AUDIO_SYNC_RESET 2
> +#define PDC_SENSORS_SYNC_RESET 3
> +#define PDC_AOP_SYNC_RESET 4
> +#define PDC_DEBUG_SYNC_RESET 5
> +#define PDC_GPU_SYNC_RESET 6
> +#define PDC_DISPLAY_SYNC_RESET 7
> +#define PDC_COMPUTE_SYNC_RESET 8
> +#define PDC_MODEM_SYNC_RESET 9
> +
> +#endif

regards
Philipp