Re: [PATCH v2 01/12] dt-bindings: mfd: stm32-fmc2: add STM32 FMC2 controller documentation

[Rob Herring]

On Wed, Apr 15, 2020 at 05:57:25PM +0200, Christophe Kerello wrote:
> This patch adds the documentation of the device tree bindings for the STM32
> FMC2 controller.
> 
> Signed-off-by: Christophe Kerello <christophe.kerello@xxxxxx>
> ---
>  .../devicetree/bindings/mfd/st,stm32-fmc2.yaml     | 370 +++++++++++++++++++++
>  1 file changed, 370 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mfd/st,stm32-fmc2.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mfd/st,stm32-fmc2.yaml b/Documentation/devicetree/bindings/mfd/st,stm32-fmc2.yaml
> new file mode 100644
> index 0000000..0ce1340
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/st,stm32-fmc2.yaml
> @@ -0,0 +1,370 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/st,stm32-fmc2.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STMicroelectronics Flexible Memory Controller 2 (FMC2) Bindings
> +
> +description: |
> +  The FMC2 functional block makes the interface with: synchronous and
> +  asynchronous static devices (such as PSNOR, PSRAM or other memory-mapped
> +  peripherals) and NAND flash memories.
> +  Its main purposes are:
> +    - to translate AXI transactions into the appropriate external device
> +      protocol
> +    - to meet the access time requirements of the external devices
> +  All external devices share the addresses, data and control signals with the
> +  controller. Each external device is accessed by means of a unique Chip
> +  Select. The FMC2 performs only one access at a time to an external device.
> +
> +maintainers:
> +  - Christophe Kerello <christophe.kerello@xxxxxx>
> +
> +properties:
> +  compatible:
> +    const: st,stm32mp1-fmc2
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  resets:
> +    maxItems: 1
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 1
> +
> +  ranges: true
> +
> +patternProperties:
> +  "^ebi(@.*)?":
> +    type: object
> +
> +    properties:
> +      compatible:
> +        const: st,stm32mp1-fmc2-ebi
> +
> +      "#address-cells":
> +        const: 2
> +
> +      "#size-cells":
> +        const: 1
> +
> +      ranges: true
> +
> +    patternProperties:
> +      "^[a-zA-Z]*-ebi@[a-f0-9,]*$":

These nodes should be named based on the device connected and we can be 
a bit more precise on the unit-address:

"@[0-9a-f],[0-9a-f]+$"

Adjust for how many chip selects there are. 15 seems unlikely.

> +        type: object
> +
> +        properties:
> +          reg:
> +            maxItems: 1
> +
> +          st,fmc2_ebi_cs_transaction_type:

s/_/-/

And for the rest of the vendor properties...

> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +              - minimum: 0
> +                maximum: 11
> +            description: |
> +                         Select one of the transactions type supported
> +                           0: Asynchronous mode 1 SRAM/FRAM
> +                           1: Asynchronous mode 1 PSRAM.
> +                           2: Asynchronous mode A SRAM/FRAM.
> +                           3: Asynchronous mode A PSRAM.
> +                           4: Asynchronous mode 2 NOR.
> +                           5: Asynchronous mode B NOR.
> +                           6: Asynchronous mode C NOR.
> +                           7: Asynchronous mode D NOR.
> +                           8: Synchronous read synchronous write PSRAM.
> +                           9: Synchronous read asynchronous write PSRAM.
> +                           10: Synchronous read synchronous write NOR.
> +                           11: Synchronous read asynchronous write NOR.
> +
> +          st,fmc2_ebi_cs_cclk_enable:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: Continuous clock enable (first bank must be configured
> +                         in synchronous mode). The FMC_CLK is generated continuously
> +                         during asynchronous and synchronous access. By default, the
> +                         FMC_CLK is only generated during synchronous access.
> +
> +          st,fmc2_ebi_cs_mux_enable:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: Address/Data multiplexed on databus (valid only with
> +                         NOR and PSRAM transactions type). By default, Address/Data are
> +                         not multiplexed.
> +
> +          st,fmc2_ebi_cs_buswidth:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +              - enum: [ 8, 16 ]
> +              - default: 16
> +            description: Data bus width
> +
> +          st,fmc2_ebi_cs_waitpol_high:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: Wait signal polarity (NWAIT signal active high).
> +                         By default, NWAIT is active low.
> +
> +          st,fmc2_ebi_cs_waitcfg_enable:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: The NWAIT signal indicates wheither the data from the
> +                         device are valid or if a wait state must be inserted when
> +                         accessing the device in synchronous mode. By default, the NWAIT
> +                         signal is active one data cycle before wait state.
> +
> +          st,fmc2_ebi_cs_wait_enable:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: The NWAIT signal is enabled (its level is taken into
> +                         account after the programmed latency period to insert wait states
> +                         if asserted). By default, the NWAIT signal is disabled.
> +
> +          st,fmc2_ebi_cs_asyncwait_enable:
> +            $ref: /schemas/types.yaml#/definitions/flag
> +            description: The NWAIT signal is taken into account during
> +                         asynchronous transactions. By default, the NWAIT signal is not
> +                         taken into account during asynchronous transactions.
> +
> +          st,fmc2_ebi_cs_cpsize:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +              - enum: [ 0, 128, 256, 512, 1024 ]
> +              - default: 0
> +            description: CRAM page size. The controller splits the burst access
> +                         when the memory page is reached. By default, no burst split when
> +                         crossing page boundary.
> +
> +          st,fmc2_ebi_cs_byte_lane_setup:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property configures the byte lane setup timing
> +                         defined in ns from NBLx low to Chip Select NEx low.

If units are nsec, then use the standard unit suffixes. Then you don't 
need to define the type either.

> +
> +          st,fmc2_ebi_cs_address_setup:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the address
> +                         setup phase in ns used for asynchronous read/write transactions.
> +
> +          st,fmc2_ebi_cs_address_hold:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the address
> +                         hold phase in ns used for asynchronous multiplexed
> +                         read/write transactions.
> +
> +          st,fmc2_ebi_cs_data_setup:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the data
> +                         setup phase in ns used for asynchronous read/write transactions.
> +
> +          st,fmc2_ebi_cs_bus_turnaround:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the delay between the end of
> +                         current read/write transaction and the next transaction.
> +
> +          st,fmc2_ebi_cs_data_hold:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the data
> +                         hold phase in ns used for asynchronous read/write transactions.
> +
> +          st,fmc2_ebi_cs_clk_period:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the FMC_CLK output signal period in ns.
> +
> +          st,fmc2_ebi_cs_data_latency:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the data latency before reading or writing
> +                         the first data. This timing is expressed in FMC_CLK periods.
> +
> +          st,fmc2_ebi_cs_write_address_setup:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the address
> +                         setup phase in ns used for asynchronous write transactions.
> +
> +          st,fmc2_ebi_cs_write_address_hold:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the address hold phase in
> +                         ns used for asynchronous multiplexed write transactions.
> +
> +          st,fmc2_ebi_cs_write_data_setup:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the data setup phase in
> +                         ns used for asynchronous write transactions.
> +
> +          st,fmc2_ebi_cs_write_bus_turnaround:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the delay between the end of current
> +                         write transaction and the next transaction.
> +
> +          st,fmc2_ebi_cs_write_data_hold:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the duration of the data hold phase
> +                         in ns used for asynchronous write transactions.
> +
> +          st,fmc2_ebi_cs_max_low_pulse:
> +            allOf:
> +              - $ref: /schemas/types.yaml#/definitions/uint32
> +            description: This property defines the maximum chip select low pulse duration
> +                         in ns for synchronous transactions. When this timing reaches 0,
> +                         the controller splits the current access, toggles NE to allow
> +                         device refresh and restarts a new access.
> +
> +        required:
> +          - reg
> +          - st,fmc2_ebi_cs_transaction_type
> +
> +    additionalProperties: false
> +
> +    required:
> +      - compatible
> +      - "#address-cells"
> +      - "#size-cells"
> +      - ranges
> +
> +  nand-controller:
> +    allOf:
> +      - $ref: "../mtd/nand-controller.yaml#"
> +
> +    type: object
> +
> +    properties:
> +      compatible:
> +        const: st,stm32mp1-fmc2-nand
> +
> +      reg:
> +        items:
> +          - description: Chip select 0 data
> +          - description: Chip select 0 command
> +          - description: Chip select 0 address space
> +          - description: Chip select 1 data
> +          - description: Chip select 1 command
> +          - description: Chip select 1 address space
> +
> +      interrupts:
> +        maxItems: 1
> +
> +      dmas:
> +        items:
> +          - description: tx DMA channel
> +          - description: rx DMA channel
> +          - description: ecc DMA channel
> +
> +      dma-names:
> +        items:
> +          - const: tx
> +          - const: rx
> +          - const: ecc
> +
> +      "#address-cells":
> +        const: 1
> +
> +      "#size-cells":
> +        const: 0
> +
> +    patternProperties:
> +      "^nand@[a-f0-9]$":
> +        type: object
> +
> +        properties:
> +          nand-ecc-step-size:
> +            const: 512
> +
> +          nand-ecc-strength:
> +            enum: [1, 4 ,8 ]
> +
> +    additionalProperties: false
> +
> +    required:
> +      - "#address-cells"
> +      - "#size-cells"
> +      - compatible
> +      - reg
> +      - interrupts
> +
> +  additionalProperties: false

Wrong indentation. You are defining a DT property called 
'additionalProperties'. You need 2 of these at 0 and 4 spaces 
indentation. I have a check for this error in dt-schema pending.

> +
> +required:
> +  - "#address-cells"
> +  - "#size-cells"
> +  - compatible
> +  - reg
> +  - clocks
> +  - ranges
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
> +    #include <dt-bindings/clock/stm32mp1-clks.h>
> +    #include <dt-bindings/reset/stm32mp1-resets.h>
> +    fmc@58002000 {
> +      #address-cells = <1>;
> +      #size-cells = <1>;
> +      compatible = "st,stm32mp1-fmc2";
> +      reg = <0x58002000 0x1000>;
> +      clocks = <&rcc FMC_K>;
> +      resets = <&rcc FMC_R>;
> +      ranges;
> +
> +      ebi@0 {
> +        #address-cells = <2>;
> +        #size-cells = <1>;
> +        compatible = "st,stm32mp1-fmc2-ebi";
> +        ranges = <0 0 0x60000000 0x4000000>,
> +                 <1 0 0x64000000 0x4000000>,
> +                 <2 0 0x68000000 0x4000000>,
> +                 <3 0 0x6c000000 0x4000000>;
> +
> +        psram-ebi@0,0 {
> +          compatible = "mtd-ram";
> +          reg = <0 0x00000000 0x100000>;
> +          bank-width = <2>;
> +
> +          st,fmc2_ebi_cs_transaction_type = <1>;
> +          st,fmc2_ebi_cs_address_setup = <60>;
> +          st,fmc2_ebi_cs_data_setup = <30>;
> +          st,fmc2_ebi_cs_bus_turnaround = <5>;
> +        };
> +      };
> +
> +      nand-controller@1 {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        compatible = "st,stm32mp1-fmc2-nand";
> +        reg = <0x80000000 0x1000>,
> +              <0x88010000 0x1000>,
> +              <0x88020000 0x1000>,
> +              <0x81000000 0x1000>,
> +              <0x89010000 0x1000>,
> +              <0x89020000 0x1000>;
> +        interrupts = <GIC_SPI 48 IRQ_TYPE_LEVEL_HIGH>;
> +        dmas = <&mdma1 20 0x2 0x12000a02 0x0 0x0>,
> +               <&mdma1 20 0x2 0x12000a08 0x0 0x0>,
> +               <&mdma1 21 0x2 0x12000a0a 0x0 0x0>;
> +        dma-names = "tx", "rx", "ecc";
> +
> +        nand@0 {
> +          reg = <0>;
> +          nand-on-flash-bbt;
> +          #address-cells = <1>;
> +          #size-cells = <1>;
> +        };
> +      };
> +    };
> +
> +...
> -- 
> 1.9.1
>