Re: [PATCH v4 08/15] dt-bindings: dma: ti: Add document for K3 UDMA

From: Rob Herring
Date: Mon Nov 04 2019 - 21:19:04 EST

On Fri, Nov 01, 2019 at 10:41:28AM +0200, Peter Ujfalusi wrote:
> New binding document for
> Texas Instruments K3 NAVSS Unified DMA â Peripheral Root Complex (UDMA-P).
>
> UDMA-P is introduced as part of the K3 architecture and can be found in
> AM654 and j721e.
>
> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> ---
> Rob,
>
> can you give me some hint on how to fix these two warnings from dt_binding_check:
>
> DTC Documentation/devicetree/bindings/dma/ti/k3-udma.example.dt.yaml
> Documentation/devicetree/bindings/dma/ti/k3-udma.example.dts:23.13-72: Warning (ranges_format): /example-0/interconnect@30800000:ranges: "ranges" property has invalid length (24 bytes) (parent #address-cells == 1, child #address-cells == 2, #size-cells == 2)
> CHECK Documentation/devicetree/bindings/dma/ti/k3-udma.example.dt.yaml

The default #address-cells is 1 for examples. So you need to
either override it or change ranges parent address size.
>
> Documentation/devicetree/bindings/dma/ti/k3-udma.example.dt.yaml: interconnect@30800000: $nodename:0: 'interconnect@30800000' does not match '^(bus|soc|axi|ahb|apb)(@[0-9a-f]+)?$'

Use 'bus' for the node name of 'simple-bus'.

>
> Thanks,
> Peter
>
> .../devicetree/bindings/dma/ti/k3-udma.yaml | 190 ++++++++++++++++++
> 1 file changed, 190 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/dma/ti/k3-udma.yaml
>
> diff --git a/Documentation/devicetree/bindings/dma/ti/k3-udma.yaml b/Documentation/devicetree/bindings/dma/ti/k3-udma.yaml
> new file mode 100644
> index 000000000000..e00fe3b2364e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/dma/ti/k3-udma.yaml
> @@ -0,0 +1,190 @@
> +# SPDX-License-Identifier: GPL-2.0

Dual license new bindings:

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/dma/ti/k3-udma.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Texas Instruments K3 NAVSS Unified DMA Device Tree Bindings
> +
> +maintainers:
> + - Peter Ujfalusi <peter.ujfalusi@xxxxxx>
> +
> +description: |
> + The UDMA-P is intended to perform similar (but significantly upgraded)
> + functions as the packet-oriented DMA used on previous SoC devices. The UDMA-P
> + module supports the transmission and reception of various packet types.
> + The UDMA-P is architected to facilitate the segmentation and reassembly of
> + SoC DMA data structure compliant packets to/from smaller data blocks that are
> + natively compatible with the specific requirements of each connected
> + peripheral.
> + Multiple Tx and Rx channels are provided within the DMA which allow multiple
> + segmentation or reassembly operations to be ongoing. The DMA controller
> + maintains state information for each of the channels which allows packet
> + segmentation and reassembly operations to be time division multiplexed between
> + channels in order to share the underlying DMA hardware. An external DMA
> + scheduler is used to control the ordering and rate at which this multiplexing
> + occurs for Transmit operations. The ordering and rate of Receive operations
> + is indirectly controlled by the order in which blocks are pushed into the DMA
> + on the Rx PSI-L interface.
> +
> + The UDMA-P also supports acting as both a UTC and UDMA-C for its internal
> + channels. Channels in the UDMA-P can be configured to be either Packet-Based
> + or Third-Party channels on a channel by channel basis.
> +
> + All transfers within NAVSS is done between PSI-L source and destination
> + threads.
> + The peripherals serviced by UDMA can be PSI-L native (sa2ul, cpsw, etc) or
> + legacy, non PSI-L native peripherals. In the later case a special, small PDMA
> + is tasked to act as a bridge between the PSI-L fabric and the legacy
> + peripheral.
> +
> + PDMAs can be configured via UDMAP peer registers to match with the
> + configuration of the legacy peripheral.
> +
> +allOf:
> + - $ref: "../dma-controller.yaml#"
> +
> +properties:
> + "#dma-cells":
> + const: 1
> + description: |
> + The cell is the PSI-L thread ID of the remote (to UDMAP) end.
> + Valid ranges for thread ID depends on the data movement direction:
> + for source thread IDs (rx): 0 - 0x7fff
> + for destination thread IDs (tx): 0x8000 - 0xffff
> +
> + PLease refer to the device documentation for the PSI-L thread map and also
> + the PSI-L peripheral chapter for the correct thread ID.
> +
> + compatible:
> + oneOf:
> + - const: ti,am654-navss-main-udmap
> + - const: ti,am654-navss-mcu-udmap
> + - const: ti,j721e-navss-main-udmap
> + - const: ti,j721e-navss-mcu-udmap

enum works better than oneOf+const. Better error messages.

> +
> + reg:
> + maxItems: 3
> +
> + reg-names:
> + items:
> + - const: gcfg
> + - const: rchanrt
> + - const: tchanrt
> +
> + msi-parent: true
> +
> + ti,sci:
> + description: |

Doesn't need to be a literal block (can drop the '|').

> + phandle to TI-SCI compatible System controller node
> + maxItems: 1

Drop this, not an array.

> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/phandle
> +
> + ti,sci-dev-id:
> + description: |
> + TI-SCI device id of UDMAP
> + maxItems: 1

Drop this.

> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32
> +
> + ti,ringacc:
> + description: |
> + phandle to the ring accelerator node
> + maxItems: 1

Drop this.

> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/phandle
> +
> + ti,sci-rm-range-tchan:
> + description: |
> + Array of UDMA tchan resource subtypes for resource allocation for this
> + host
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32-array
> + items:
> + minItems: 1
> + # Should be enough
> + maxItems: 255

These should not be under 'items'. Drop 'items'.

Any constraints on the values of the array elements?

> +
> + ti,sci-rm-range-rchan:
> + description: |
> + Array of UDMA rchan resource subtypes for resource allocation for this
> + host
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32-array
> + items:
> + minItems: 1
> + # Should be enough
> + maxItems: 255

Same here.

> +
> + ti,sci-rm-range-rflow:
> + description: |
> + Array of UDMA rflow resource subtypes for resource allocation for this
> + host
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32-array
> + items:
> + minItems: 1
> + # Should be enough
> + maxItems: 255

And here.

> +
> +required:
> + - compatible
> + - "#dma-cells"
> + - reg
> + - reg-names
> + - msi-parent
> + - ti,sci
> + - ti,sci-dev-id
> + - ti,ringacc
> + - ti,sci-rm-range-tchan
> + - ti,sci-rm-range-rchan
> + - ti,sci-rm-range-rflow
> +
> +examples:
> + - |+
> + cbass_main_navss: interconnect@30800000 {
> + compatible = "simple-bus";
> + #address-cells = <2>;
> + #size-cells = <2>;
> + dma-coherent;
> + dma-ranges;
> + ranges = <0x00 0x30800000 0x00 0x30800000 0x00 0x0bc00000>;
> +
> + ti,sci-dev-id = <118>;
> +
> + main_udmap: dma-controller@31150000 {
> + compatible = "ti,am654-navss-main-udmap";
> + reg = <0x0 0x31150000 0x0 0x100>,
> + <0x0 0x34000000 0x0 0x100000>,
> + <0x0 0x35000000 0x0 0x100000>;
> + reg-names = "gcfg", "rchanrt", "tchanrt";
> + #dma-cells = <1>;
> +
> + ti,ringacc = <&ringacc>;
> +
> + msi-parent = <&inta_main_udmass>;
> +
> + ti,sci = <&dmsc>;
> + ti,sci-dev-id = <188>;
> +
> + ti,sci-rm-range-tchan = <0x1>, /* TX_HCHAN */
> + <0x2>; /* TX_CHAN */
> + ti,sci-rm-range-rchan = <0x4>, /* RX_HCHAN */
> + <0x5>; /* RX_CHAN */
> + ti,sci-rm-range-rflow = <0x6>; /* GP RFLOW */
> + };
> + };
> +
> + mcasp0: mcasp@02B00000 {
> + dmas = <&main_udmap 0xc400>, <&main_udmap 0x4400>;
> + dma-names = "tx", "rx";
> + };
> +
> + crypto: crypto@4E00000 {
> + compatible = "ti,sa2ul-crypto";
> +
> + dmas = <&main_udmap 0xc000>, <&main_udmap 0x4000>, <&main_udmap 0x4001>;
> + dma-names = "tx", "rx1", "rx2";
> + };
> +
> --
> Peter
>
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
> Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>