Re: [PATCH v2 10/19] dt-bindings: dma: ti: Add document for K3 BCDMA
From: Rob Herring <robh@kernel.org>
Date: 2020-12-07 19:43:18
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dmaengine, linux-arm-kernel, lkml
On Tue, Nov 17, 2020 at 12:56:47PM +0200, Peter Ujfalusi wrote:
quoted hunk ↗ jump to hunk
New binding document for Texas Instruments K3 Block Copy DMA (BCDMA). BCDMA is introduced as part of AM64. Signed-off-by: Peter Ujfalusi <redacted> --- .../devicetree/bindings/dma/ti/k3-bcdma.yaml | 175 ++++++++++++++++++ 1 file changed, 175 insertions(+) create mode 100644 Documentation/devicetree/bindings/dma/ti/k3-bcdma.yamldiff --git a/Documentation/devicetree/bindings/dma/ti/k3-bcdma.yaml b/Documentation/devicetree/bindings/dma/ti/k3-bcdma.yaml new file mode 100644 index 000000000000..c6d76641ebec --- /dev/null +++ b/Documentation/devicetree/bindings/dma/ti/k3-bcdma.yaml@@ -0,0 +1,175 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/dma/ti/k3-bcdma.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Texas Instruments K3 DMSS BCDMA Device Tree Bindings + +maintainers: + - Peter Ujfalusi <peter.ujfalusi@ti.com> + +description: | + The Block Copy DMA (BCDMA) is intended to perform similar functions as the TR + mode channels of K3 UDMA-P. + BCDMA includes block copy channels and Split channels. + + Block copy channels mainly used for memory to memory transfers, but with + optional triggers a block copy channel can service peripherals by accessing + directly to memory mapped registers or area. + + Split channels can be used to service PSI-L based peripherals. + The peripherals can be PSI-L native or legacy, non PSI-L native peripherals + with PDMAs. PDMA is tasked to act as a bridge between the PSI-L fabric and the + legacy peripheral. + + PDMAs can be configured via BCDMA split channel's peer registers to match with + the configuration of the legacy peripheral. + +allOf: + - $ref: /schemas/dma/dma-controller.yaml# + +properties: + "#dma-cells": + const: 3 + description: | + cell 1: type of the BCDMA channel to be used to service the peripheral: + 0 - split channel + 1 - block copy channel using global trigger 1 + 2 - block copy channel using global trigger 2 + 3 - block copy channel using local trigger + + cell 2: parameter for the channel: + if cell 1 is 0 (split channel): + PSI-L thread ID of the remote (to BCDMA) 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. + if cell 1 is 1 or 2 (block copy channel using global trigger): + Unused, ignored + + The trigger must be configured for the channel externally to BCDMA, + channels using global triggers should not be requested directly, but + via DMA event router. + if cell 1 is 3 (block copy channel using local trigger): + bchan number of the locally triggered channel + + cell 3: ASEL value for the channel + + compatible: + enum: + - ti,am64-dmss-bcdma
Typically, we put 'compatible' first.
+ "#address-cells": + const: 2 + + "#size-cells": + const: 2
These apply to child nodes, but you don't have any.
+
+ reg:
+ maxItems: 5
+
+ reg-names:
+ items:
+ - const: gcfg
+ - const: bchanrt
+ - const: rchanrt
+ - const: tchanrt
+ - const: ringrt
+
+ msi-parent: true
+
+ ti,asel:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: ASEL value for non slave channels
+
+ ti,sci-rm-range-bchan:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: |
+ Array of BCDMA block-copy channel resource subtypes for resource
+ allocation for this host
+ minItems: 1
+ # Should be enough
+ maxItems: 255
+ items:
+ maximum: 0x3f
+
+ ti,sci-rm-range-tchan:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: |
+ Array of BCDMA split tx channel resource subtypes for resource allocation
+ for this host
+ minItems: 1
+ # Should be enough
+ maxItems: 255
+ items:
+ maximum: 0x3f
+
+ ti,sci-rm-range-rchan:
+ $ref: /schemas/types.yaml#/definitions/uint32-array
+ description: |
+ Array of BCDMA split rx channel resource subtypes for resource allocation
+ for this host
+ minItems: 1
+ # Should be enough
+ maxItems: 255
+ items:
+ maximum: 0x3f
+
+required:
+ - compatible
+ - "#address-cells"
+ - "#size-cells"
+ - "#dma-cells"
+ - reg
+ - reg-names
+ - msi-parent
+ - ti,sci
+ - ti,sci-dev-id
+ - ti,sci-rm-range-bchan
+ - ti,sci-rm-range-tchan
+ - ti,sci-rm-range-rchan
+
+unevaluatedProperties: false
+
+examples:
+ - |+
+ cbass_main {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ main_dmss {
+ compatible = "simple-mfd";
+ #address-cells = <2>;
+ #size-cells = <2>;
+ dma-ranges;
+ ranges;
+
+ ti,sci-dev-id = <25>;
+
+ main_bcdma: dma-controller@485c0100 {
+ compatible = "ti,am64-dmss-bcdma";
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ reg = <0x0 0x485c0100 0x0 0x100>,
+ <0x0 0x4c000000 0x0 0x20000>,
+ <0x0 0x4a820000 0x0 0x20000>,
+ <0x0 0x4aa40000 0x0 0x20000>,
+ <0x0 0x4bc00000 0x0 0x100000>;
+ reg-names = "gcfg", "bchanrt", "rchanrt", "tchanrt", "ringrt";
+ msi-parent = <&inta_main_dmss>;
+ #dma-cells = <3>;
+
+ ti,sci = <&dmsc>;
+ ti,sci-dev-id = <26>;
+
+ ti,sci-rm-range-bchan = <0x20>; /* BLOCK_COPY_CHAN */
+ ti,sci-rm-range-rchan = <0x21>; /* SPLIT_TR_RX_CHAN */
+ ti,sci-rm-range-tchan = <0x22>; /* SPLIT_TR_TX_CHAN */
+ };
+ };
+ };
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki