Re: [PATCH v5 10/14] dt-bindings: firmware: Add fsl,scu yaml file

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 16/06/2022 18:42, Viorel Suman wrote:
> From: Abel Vesa <abel.vesa@nxp.com>
> 
> In order to replace the fsl,scu txt file from bindings/arm/freescale,
> we need to split it between the right subsystems. This patch adds the
> fsl,scu.yaml in the firmware bindings folder. This one is only for
> the main SCU node. The old txt file will be removed only after all
> the child nodes have been properly switch to yaml.
> 
> Signed-off-by: Abel Vesa <abel.vesa@nxp.com>
> Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
> ---
>  .../devicetree/bindings/firmware/fsl,scu.yaml | 170 ++++++++++++++++++
>  1 file changed, 170 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/firmware/fsl,scu.yaml
> 
> diff --git a/Documentation/devicetree/bindings/firmware/fsl,scu.yaml b/Documentation/devicetree/bindings/firmware/fsl,scu.yaml
> new file mode 100644
> index 000000000000..a28f729bfadb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/firmware/fsl,scu.yaml
> @@ -0,0 +1,170 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/firmware/fsl,scu.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NXP i.MX System Controller Firmware (SCFW)
> +
> +maintainers:
> +  - Dong Aisheng <aisheng.dong@nxp.com>
> +
> +description: System Controller Device Node
> +  The System Controller Firmware (SCFW) is a low-level system function
> +  which runs on a dedicated Cortex-M core to provide power, clock, and
> +  resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
> +  (QM, QP), and i.MX8QX (QXP, DX).
> +  The AP communicates with the SC using a multi-ported MU module found
> +  in the LSIO subsystem. The current definition of this MU module provides
> +  5 remote AP connections to the SC to support up to 5 execution environments
> +  (TZ, HV, standard Linux, etc.). The SC side of this MU module interfaces
> +  with the LSIO DSC IP bus. The SC firmware will communicate with this MU
> +  using the MSI bus.
> +
> +properties:
> +  $nodename:
> +    const: 'scu'

Why enforcing node name? Second point is that node names should be
generic, so I wonder what "SCU" exactly means and whether it is generic?

> +
> +  compatible:
> +    const: fsl,imx-scu
> +
> +  clock-controller:
> +    description: |
> +      $ref: /schemas/clock/fsl,scu-clk.yaml

That's not a valid syntax. ref is not part of description

> +      Clock controller node that provides the clocks controlled by the SCU
> +
> +  imx8qx-ocotp:
> +    description: |
> +      $ref: /schemas/nvmem/fsl,scu-ocotp.yaml
> +      OCOTP controller node provided by the SCU
> +
> +  keys:
> +    description: |
> +      $ref: /schemas/input/fsl,scu-key.yaml
> +      Keys provided by the SCU
> +
> +  mboxes:
> +    description: |
> +      $ref: /schemas/mailbox/fsl,mu.yaml
> +      List of phandle of 4 MU channels for tx, 4 MU channels for
> +      rx, and 1 optional MU channel for general interrupt.
> +      All MU channels must be in the same MU instance.
> +      Cross instances are not allowed. The MU instance can only
> +      be one of LSIO MU0~M4 for imx8qxp and imx8qm. Users need
> +      to make sure use the one which is not conflict with other
> +      execution environments. e.g. ATF.
> +    minItems: 1
> +    maxItems: 10
> +
> +  mbox-names:
> +    description:
> +      include "gip3" if want to support general MU interrupt.
> +    minItems: 1
> +    maxItems: 10
> +
> +  pinctrl:
> +    description: |
> +      $ref: /schemas/pinctrl/fsl,scu-pinctrl.yaml
> +      Pin controller provided by the SCU
> +
> +  power-controller:
> +    description: |
> +      $ref: /schemas/power/fsl,scu-pd.yaml
> +      Power domains controller node that provides the power domains
> +      controlled by the SCU
> +
> +  rtc:
> +    description: |
> +      $ref: /schemas/rtc/fsl,scu-rtc.yaml
> +      RTC controller provided by the SCU
> +
> +  thermal-sensor:
> +    description: |
> +      $ref: /schemas/thermal/fsl,scu-thermal.yaml
> +      Thermal sensor provided by the SCU
> +
> +  watchdog:
> +    description: |
> +      $ref: /schemas/watchdog/fsl,scu-wdt.yaml
> +      Watchdog controller provided by the SCU
> +
> +required:
> +  - compatible
> +  - mbox-names
> +  - mboxes
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/firmware/imx/rsrc.h>
> +    #include <dt-bindings/input/input.h>
> +    #include <dt-bindings/pinctrl/pads-imx8qxp.h>
> +
> +    firmware {
> +           scu {
> +                   compatible = "fsl,imx-scu";
> +                   mbox-names = "tx0", "tx1", "tx2", "tx3",
> +                                "rx0", "rx1", "rx2", "rx3",
> +                                "gip3";
> +                   mboxes = <&lsio_mu1 0 0
> +                            &lsio_mu1 0 1
> +                            &lsio_mu1 0 2
> +                            &lsio_mu1 0 3
> +                            &lsio_mu1 1 0
> +                            &lsio_mu1 1 1
> +                            &lsio_mu1 1 2
> +                            &lsio_mu1 1 3
> +                            &lsio_mu1 3 3>;
> +
> +                   clock-controller {
> +                            compatible = "fsl,imx8qxp-clk", "fsl,scu-clk";
> +                            #clock-cells = <2>;
> +                   };
> +
> +                   pinctrl {
> +                            compatible = "fsl,imx8qxp-iomuxc";
> +
> +                            pinctrl_lpuart0: lpuart0grp {
> +                                   fsl,pins = <
> +                                           IMX8QXP_UART0_RX_ADMA_UART0_RX   0x06000020
> +                                           IMX8QXP_UART0_TX_ADMA_UART0_TX   0x06000020
> +                                   >;
> +                            };
> +                   };
> +
> +                   imx8qx-ocotp {
> +                            compatible = "fsl,imx8qxp-scu-ocotp";
> +                            #address-cells = <1>;
> +                            #size-cells = <1>;
> +
> +                            fec_mac0: mac@2c4 {
> +                                   reg = <0x2c4 6>;
> +                            };
> +                   };
> +
> +                   power-controller {
> +                            compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd";
> +                            #power-domain-cells = <1>;
> +                   };
> +
> +                   rtc {
> +                            compatible = "fsl,imx8qxp-sc-rtc";
> +                   };
> +
> +                   keys {
> +                            compatible = "fsl,imx8qxp-sc-key", "fsl,imx-sc-key";
> +                            linux,keycodes = <KEY_POWER>;
> +                   };
> +
> +                   watchdog {
> +                            compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
> +                            timeout-sec = <60>;
> +                   };
> +
> +                   thermal-sensor {
> +                            compatible = "fsl,imx8qxp-sc-thermal", "fsl,imx-sc-thermal";
> +                            #thermal-sensor-cells = <1>;
> +                   };
> +            };
> +    };


Best regards,
Krzysztof