Convert the QEMU fw-cfg binding to DT schema format. As this binding is also used on Risc-V now, drop any architecture references and move to a common location. The fw-cfg interface has also gained some DMA support which is coherent, so add the missing 'dma-coherent'. Signed-off-by: Rob Herring <robh@xxxxxxxxxx> --- .../devicetree/bindings/arm/fw-cfg.txt | 38 ------------- .../bindings/firmware/qemu,fw-cfg-mmio.yaml | 54 +++++++++++++++++++ 2 files changed, 54 insertions(+), 38 deletions(-) delete mode 100644 Documentation/devicetree/bindings/arm/fw-cfg.txt create mode 100644 Documentation/devicetree/bindings/firmware/qemu,fw-cfg-mmio.yaml diff --git a/Documentation/devicetree/bindings/arm/fw-cfg.txt b/Documentation/devicetree/bindings/arm/fw-cfg.txt deleted file mode 100644 index fd54e1db2156..000000000000 --- a/Documentation/devicetree/bindings/arm/fw-cfg.txt +++ /dev/null @@ -1,38 +0,0 @@ -* QEMU Firmware Configuration bindings for ARM - -QEMU's arm-softmmu and aarch64-softmmu emulation / virtualization targets -provide the following Firmware Configuration interface on the "virt" machine -type: - -- A write-only, 16-bit wide selector (or control) register, -- a read-write, 64-bit wide data register. - -QEMU exposes the control and data register to ARM guests as memory mapped -registers; their location is communicated to the guest's UEFI firmware in the -DTB that QEMU places at the bottom of the guest's DRAM. - -The authoritative guest-side hardware interface documentation to the fw_cfg -device can be found in "docs/specs/fw_cfg.txt" in the QEMU source tree. - - -Required properties: - -- compatible: "qemu,fw-cfg-mmio". - -- reg: the MMIO region used by the device. - * Bytes 0x0 to 0x7 cover the data register. - * Bytes 0x8 to 0x9 cover the selector register. - * Further registers may be appended to the region in case of future interface - revisions / feature bits. - -Example: - -/ { - #size-cells = <0x2>; - #address-cells = <0x2>; - - fw-cfg@9020000 { - compatible = "qemu,fw-cfg-mmio"; - reg = <0x0 0x9020000 0x0 0xa>; - }; -}; diff --git a/Documentation/devicetree/bindings/firmware/qemu,fw-cfg-mmio.yaml b/Documentation/devicetree/bindings/firmware/qemu,fw-cfg-mmio.yaml new file mode 100644 index 000000000000..3aac9448e7f1 --- /dev/null +++ b/Documentation/devicetree/bindings/firmware/qemu,fw-cfg-mmio.yaml @@ -0,0 +1,54 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/firmware/qemu,fw-cfg-mmio.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: QEMU Firmware Configuration bindings + +maintainers: + - Laszlo Ersek <lersek@xxxxxxxxxx> + +description: | + Various QEMU emulation / virtualization targets provide the following + Firmware Configuration interface on the "virt" machine type: + + - A write-only, 16-bit wide selector (or control) register, + - a read-write, 64-bit wide data register. + + QEMU exposes the control and data register to guests as memory mapped + registers; their location is communicated to the guest's UEFI firmware in the + DTB that QEMU places at the bottom of the guest's DRAM. + + The authoritative guest-side hardware interface documentation to the fw_cfg + device can be found in "docs/specs/fw_cfg.txt" in the QEMU source tree. + + +properties: + compatible: + const: qemu,fw-cfg-mmio + + reg: + maxItems: 1 + description: | + * Bytes 0x0 to 0x7 cover the data register. + * Bytes 0x8 to 0x9 cover the selector register. + * Further registers may be appended to the region in case of future interface + revisions / feature bits. + + dma-coherent: true + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + + fw-cfg@9020000 { + compatible = "qemu,fw-cfg-mmio"; + reg = <0x9020000 0xa>; + }; +... -- 2.32.0