Re: [PATCH v5 01/10] dt-bindings: soc: fsl: cpm_qe: Add TSA controller

From: Krzysztof Kozlowski
Date: Fri Feb 17 2023 - 04:15:01 EST

On 16/02/2023 14:42, Herve Codina wrote:
> Add support for the time slot assigner (TSA)
> available in some PowerQUICC SoC such as MPC885
> or MPC866.
>
> Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
> ---
> .../bindings/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml | 234 ++++++++++++++++++
> include/dt-bindings/soc/fsl,tsa.h | 13 +
> 2 files changed, 247 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml
> create mode 100644 include/dt-bindings/soc/fsl,tsa.h
>
> diff --git a/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml b/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml
> new file mode 100644
> index 000000000000..bcd03f89780e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml
> @@ -0,0 +1,234 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/soc/fsl/cpm_qe/fsl,cpm1-tsa.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: PowerQUICC CPM Time-slot assigner (TSA) controller
> +
> +maintainers:
> + - Herve Codina <herve.codina@xxxxxxxxxxx>
> +
> +description:
> + The TSA is the time-slot assigner that can be found on some PowerQUICC SoC.
> + Its purpose is to route some TDM time-slots to other internal serial
> + controllers.
> +
> +properties:
> + compatible:
> + items:
> + - enum:
> + - fsl,mpc885-tsa
> + - fsl,mpc866-tsa
> + - const: fsl,cpm1-tsa
> +
> + reg:
> + items:
> + - description: SI (Serial Interface) register base
> + - description: SI RAM base
> +
> + reg-names:
> + items:
> + - const: si_regs
> + - const: si_ram
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + '#fsl,serial-cells':
> + $ref: /schemas/types.yaml#/definitions/uint32
> + const: 1
> + description:
> + TSA consumers that use a phandle to TSA need to pass the serial identifier
> + with this phandle (defined in dt-bindings/soc/fsl,tsa.h).
> + For instance "fsl,tsa-serial = <&tsa FSL_CPM_TSA_SCC4>;".
> +
> +patternProperties:
> + '^tdm@[0-1]$':
> + description:
> + The TDM managed by this controller
> + type: object
> +
> + additionalProperties: false
> +
> + properties:
> + reg:
> + minimum: 0
> + maximum: 1
> + description:
> + The TDM number for this TDM, 0 for TDMa and 1 for TDMb
> +
> + fsl,common-rxtx-pins:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description:
> + The hardware can use four dedicated pins for Tx clock, Tx sync, Rx
> + clock and Rx sync or use only two pins, Tx/Rx clock and Tx/Rx sync.
> + Without the 'fsl,common-rxtx-pins' property, the four pins are used.
> + With the 'fsl,common-rxtx-pins' property, two pins are used.
> +
> + clocks:
> + minItems: 2
> + items:
> + - description: External clock connected to L1RSYNC pin
> + - description: External clock connected to L1RCLK pin
> + - description: External clock connected to L1TSYNC pin
> + - description: External clock connected to L1TCLK pin

Blank line

> + clock-names:
> + minItems: 2
> + items:
> + - const: l1rsync
> + - const: l1rclk
> + - const: l1tsync
> + - const: l1tclk
> +
> + fsl,diagnostic-mode:
> + $ref: /schemas/types.yaml#/definitions/string
> + enum: [disabled, echo, internal-loopback, control-loopback]
> + default: disabled
> + description: |
> + The diagnostic mode can be used to diagnose some communication issues.
> + It should not be set (or set to 'disabled') when diagnostic is not
> + needed.

I don't think this is property for DT. Are you going to ship devices to
customers with diagnostic mode? As you explained: no, so this can never
appear. You might need sysfs/debugfs knob.

You already got a comment for this. Your explanation "I plan" is not an
explanation why DT is suitable for such property. So let's make it more
obvious: drop it.

> + Diagnostic mode:
> + - disabled:
> + Diagnostic disabled (ie. normal operation)
> + - echo:
> + Automatic echo. Rx data is resent on Tx.
> + - internal-loopback:
> + The TDM transmitter is connected to the receiver. Data appears
> + on Tx pin.
> + - control-loopback:
> + The TDM transmitter is connected to the receiver. The Tx pin is
> + disconnected.
> +
> + fsl,rx-frame-sync-delay-bits:
> + enum: [0, 1, 2, 3]

maxItems: 1

> + default: 0
> + description: |
> + Receive frame sync delay in number of bits.
> + Indicates the delay between the Rx sync and the first bit of the Rx
> + frame. 0 for no bit delay. 1, 2 or 3 for 1, 2 or 3 bits delay.
> +
> + fsl,tx-frame-sync-delay-bits:
> + enum: [0, 1, 2, 3]

maxItems: 1

> + default: 0
> + description: |
> + Transmit frame sync delay in number of bits.
> + Indicates the delay between the Tx sync and the first bit of the Tx
> + frame. 0 for no bit delay. 1, 2 or 3 for 1, 2 or 3 bits delay.
> +
> + fsl,clock-falling-edge:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description:
> + Data is sent on falling edge of the clock (and received on the rising
> + edge). If 'clock-falling-edge' is not present, data is sent on the
> + rising edge (and received on the falling edge).
> +
> + fsl,fsync-rising-edge:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description:
> + Frame sync pulses are sampled with the rising edge of the channel
> + clock. If 'fsync-rising-edge' is not present, pulses are sampled with
> + the falling edge.
> +
> + fsl,double-speed-clock:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description:
> + The channel clock is twice the data rate.
> +
> + patternProperties:
> + '^fsl,[rt]x-ts-routes$':
> + $ref: /schemas/types.yaml#/definitions/uint32-matrix
> + description: |
> + A list of tuple that indicates the Tx or Rx time-slots routes.
> + items:
> + items:
> + - description:
> + The number of time-slots
> + minimum: 1
> + maximum: 64
> + - description: |
> + The source (Tx) or destination (Rx) serial interface
> + (dt-bindings/soc/fsl,tsa.h defines these values)
> + - 0: No destination
> + - 1: SCC2
> + - 2: SCC3
> + - 3: SCC4
> + - 4: SMC1
> + - 5: SMC2
> + enum: [0, 1, 2, 3, 4, 5]
> + minItems: 1
> + maxItems: 64
> +
> + allOf:
> + # If fsl,common-rxtx-pins is present, only 2 clocks are needed.
> + # Else, the 4 clocks must be present.
> + - if:
> + required:
> + - fsl,common-rxtx-pins
> + then:
> + properties:
> + clocks:
> + maxItems: 2
> + clock-names:
> + maxItems: 2
> + else:
> + properties:
> + clocks:
> + minItems: 4
> + clock-names:
> + minItems: 4
> +
> + required:
> + - reg
> + - clocks
> + - clock-names
> +
> +required:
> + - compatible
> + - reg
> + - reg-names
> + - '#address-cells'
> + - '#size-cells'
> + - '#fsl,serial-cells'
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/soc/fsl,tsa.h>
> +
> + tsa@ae0 {
> + compatible = "fsl,mpc885-tsa", "fsl,cpm1-tsa";
> + reg = <0xae0 0x10>,
> + <0xc00 0x200>;
> + reg-names = "si_regs", "si_ram";
> +
> + #address-cells = <1>;
> + #size-cells = <0>;
> + #fsl,serial-cells = <1>;
> +
> + tdm@0 {
> + /* TDMa */
> + reg = <0>;
> +
> + clocks = <&clk_l1rsynca>, <&clk_l1rclka>;
> + clock-names = "l1rsync", "l1rclk";
> +
> + fsl,common-rxtx-pins;
> + fsl,fsync-rising-edge;
> +
> + fsl,tx-ts-routes = < 2 0 >, /* TS 0..1 */

No spaces after < and before >

> + < 24 FSL_CPM_TSA_SCC4 >, /* TS 2..25 */
> + < 1 0 >, /* TS 26 */
> + < 5 FSL_CPM_TSA_SCC3 >; /* TS 27..31 */
> +
> + fsl,rx-ts-routes = < 2 0 >, /* TS 0..1 */
> + < 24 FSL_CPM_TSA_SCC4 >, /* 2..25 */
> + < 1 0 >, /* TS 26 */
> + < 5 FSL_CPM_TSA_SCC3 >; /* TS 27..31 */
> + };
> + };
> diff --git a/include/dt-bindings/soc/fsl,tsa.h b/include/dt-bindings/soc/fsl,tsa.h
> new file mode 100644
> index 000000000000..2cc44e867dbe
> --- /dev/null
> +++ b/include/dt-bindings/soc/fsl,tsa.h

Use same name as binding file.

> @@ -0,0 +1,13 @@
> +/* SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause */
> +
> +#ifndef __DT_BINDINGS_SOC_FSL_TSA_H
> +#define __DT_BINDINGS_SOC_FSL_TSA_H

Best regards,
Krzysztof