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 <[email protected]>
---
.../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 <[email protected]>
+
+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
On 03/10/22 02:35, Rob Herring wrote:
> 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 <[email protected]>
> ---
> .../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 <[email protected]>
Ugh :) I guess this is based on my authorship of historical commit
53275a61bc7a ("devicetree: document ARM bindings for QEMU's Firmware
Config interface", 2015-01-13), and prehaps my R-b on commit
92aed5d6ba90 ("devicetree: update documentation for fw_cfg ARM
bindings", 2016-02-09).
However -- I totally can't maintain this file. (I mean I've probably not
done anything related to it in the past seven years, so I guess it's
time to admit that fact!)
Rob, would you please consider taking it over?
With my name+email replaced with yours:
Acked-by: Laszlo Ersek <[email protected]>
Thank you!
Laszlo
> +
> +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>;
> + };
> +...
>
On 10/03/2022 02:35, Rob Herring wrote:
> 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 <[email protected]>
> ---
> .../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
>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Best regards,
Krzysztof
On Thu, Mar 10, 2022 at 10:05:04AM +0100, Laszlo Ersek wrote:
> On 03/10/22 02:35, Rob Herring wrote:
> > 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 <[email protected]>
> > ---
> > .../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 <[email protected]>
>
> Ugh :) I guess this is based on my authorship of historical commit
> 53275a61bc7a ("devicetree: document ARM bindings for QEMU's Firmware
> Config interface", 2015-01-13), and prehaps my R-b on commit
> 92aed5d6ba90 ("devicetree: update documentation for fw_cfg ARM
> bindings", 2016-02-09).
>
> However -- I totally can't maintain this file. (I mean I've probably not
> done anything related to it in the past seven years, so I guess it's
> time to admit that fact!)
>
> Rob, would you please consider taking it over?
Yeah, no problem.
> With my name+email replaced with yours:
>
> Acked-by: Laszlo Ersek <[email protected]>
>
> Thank you!
> Laszlo