[PATCH v2 10/19] dt-bindings: dma: ti: Add document for K3 BCDMA

Peter Ujfalusi
2020-11-17T10:57:31Z

New binding document for
Texas Instruments K3 Block Copy DMA (BCDMA).

BCDMA is introduced as part of AM64.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
.../devicetree/bindings/dma/ti/k3-bcdma.yaml | 175 ++++++++++++++++++
1 file changed, 175 insertions(+)
create mode 100644 Documentation/devicetree/bindings/dma/ti/k3-bcdma.yaml

diff --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
+
+ "#address-cells":
+ const: 2
+
+ "#size-cells":
+ const: 2
+
+ 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 */
+ };
+ };
+ };