Add the binding to use the ACPI wakeup mailbox mechanism to bringup APs. Signed-off-by: Yunhong Jiang <yunhong.jiang@xxxxxxxxxxxxxxx> --- .../devicetree/bindings/x86/wakeup.yaml | 41 +++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 Documentation/devicetree/bindings/x86/wakeup.yaml diff --git a/Documentation/devicetree/bindings/x86/wakeup.yaml b/Documentation/devicetree/bindings/x86/wakeup.yaml new file mode 100644 index 000000000000..8af40dcdb592 --- /dev/null +++ b/Documentation/devicetree/bindings/x86/wakeup.yaml @@ -0,0 +1,41 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 + +$id: http://devicetree.org/schemas/x86/wakeup.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: x86 acpi wakeup mailbox + +description: | + +This document describes the "acpi-wakeup-mailbox" method for enabling secondary +CPUs. + +The ACPI spec defines a mechanism to let the bootstrap processor wake up +application processors with a mailbox. The "acpi-wakeup-mailbox" enable-method +follows the "Multiprocessor Wakeup Mailbox Structure" defined in the ACPI +spec[1]. + +Since the ACPI mailbox structure is shared by all the CPUs, this enable method +applies to all CPUs and should be defined in the "cpus" node and should not be +defined on each "cpu" node. + +select: false + +properties: + wakeup-mailbox-addr: + $ref: /schemas/types.yaml#/definitions/uint64 + description: | + The physical address of the wakeup mailbox data structure. The address must + meet the ACPI spec requirement, like be 4K bytes aligned and it should be in + the reserved memory. + + wakeup-mailbox-version: + $ref: /schemas/types.yaml#/definitions/uint64 + description: | + The MailBoxVersion defined in the ACPI spec that this binding follows. + +required: + - wakeup-mailbox-addr + +[1] https://uefi.org/htmlspecs/ACPI_Spec_6_4_html/05_ACPI_Software_Programming_Model/ACPI_Software_Programming_Model.html#multiprocessor-wakeup-structure -- 2.25.1
