Bring the device tree binding document from Linux to u-boot
Port from linux patches: Link: https://lore.kernel.org/r/20230207065826.285013-2-william.zhang@broadcom.com Link: https://lore.kernel.org/r/20230207065826.285013-3-william.zhang@broadcom.com
Signed-off-by: William Zhang william.zhang@broadcom.com ---
.../spi/brcm,bcm63xx-hsspi.yaml | 134 ++++++++++++++++++ 1 file changed, 134 insertions(+) create mode 100644 doc/device-tree-bindings/spi/brcm,bcm63xx-hsspi.yaml
diff --git a/doc/device-tree-bindings/spi/brcm,bcm63xx-hsspi.yaml b/doc/device-tree-bindings/spi/brcm,bcm63xx-hsspi.yaml new file mode 100644 index 000000000000..6554978583f8 --- /dev/null +++ b/doc/device-tree-bindings/spi/brcm,bcm63xx-hsspi.yaml @@ -0,0 +1,134 @@ +# SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/spi/brcm,bcm63xx-hsspi.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Broadcom Broadband SoC High Speed SPI controller + +maintainers: + - William Zhang william.zhang@broadcom.com + - Kursad Oney kursad.oney@broadcom.com + - Jonas Gorski jonas.gorski@gmail.com + +description: | + Broadcom Broadband SoC supports High Speed SPI master controller since the + early MIPS based chips such as BCM6328 and BCM63268. This initial rev 1.0 + controller was carried over to recent ARM based chips, such as BCM63138, + BCM4908 and BCM6858. The old MIPS based chip should continue to use the + brcm,bcm6328-hsspi compatible string. The recent ARM based chip is required to + use the brcm,bcmbca-hsspi-v1.0 as part of its compatible string list as + defined below to match the specific chip along with ip revision info. + + This rev 1.0 controller has a limitation that can not keep the chip select line + active between the SPI transfers within the same SPI message. This can + terminate the transaction to some SPI devices prematurely. The issue can be + worked around by either the controller's prepend mode or using the dummy chip + select workaround. Driver automatically picks the suitable mode based on + transfer type so it is transparent to the user. + + The newer SoCs such as BCM6756, BCM4912 and BCM6855 include an updated SPI + controller rev 1.1 that add the capability to allow the driver to control chip + select explicitly. This solves the issue in the old controller. + +properties: + compatible: + oneOf: + - const: brcm,bcm6328-hsspi + - items: + - enum: + - brcm,bcm47622-hsspi + - brcm,bcm4908-hsspi + - brcm,bcm63138-hsspi + - brcm,bcm63146-hsspi + - brcm,bcm63148-hsspi + - brcm,bcm63158-hsspi + - brcm,bcm63178-hsspi + - brcm,bcm6846-hsspi + - brcm,bcm6856-hsspi + - brcm,bcm6858-hsspi + - brcm,bcm6878-hsspi + - const: brcm,bcmbca-hsspi-v1.0 + - items: + - enum: + - brcm,bcm4912-hsspi + - brcm,bcm6756-hsspi + - brcm,bcm6813-hsspi + - brcm,bcm6855-hsspi + - const: brcm,bcmbca-hsspi-v1.1 + + reg: + items: + - description: main registers + - description: miscellaneous control registers + minItems: 1 + + reg-names: + items: + - const: hsspi + - const: spim-ctrl + minItems: 1 + + clocks: + items: + - description: SPI master reference clock + - description: SPI master pll clock + + clock-names: + items: + - const: hsspi + - const: pll + + interrupts: + maxItems: 1 + +required: + - compatible + - reg + - clocks + - clock-names + - interrupts + +allOf: + - $ref: spi-controller.yaml# + - if: + properties: + compatible: + contains: + enum: + - brcm,bcm6328-hsspi + - brcm,bcmbca-hsspi-v1.0 + then: + properties: + reg: + maxItems: 1 + reg-names: + maxItems: 1 + else: + properties: + reg: + minItems: 2 + maxItems: 2 + reg-names: + minItems: 2 + maxItems: 2 + required: + - reg-names + +unevaluatedProperties: false + +examples: + - | + #include <dt-bindings/interrupt-controller/arm-gic.h> + spi@ff801000 { + compatible = "brcm,bcm6756-hsspi", "brcm,bcmbca-hsspi-v1.1"; + reg = <0xff801000 0x1000>, + <0xff802610 0x4>; + reg-names = "hsspi", "spim-ctrl"; + interrupts = <GIC_SPI 36 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&hsspi>, <&hsspi_pll>; + clock-names = "hsspi", "pll"; + num-cs = <8>; + #address-cells = <1>; + #size-cells = <0>; + };