Be specific that an EBBR platform must provide either ACPI or Devicetree data in the EFI configuration table, but not both. Platforms are allowed to support both ACPI & DT booting as a configuration option, but only one interface can be presented to the OS at a time.
Also add references to the ACPI and Devicetree specifications. Fixes #5 Signed-off-by: Grant Likely <[email protected]> --- source/ebbr.rst | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/source/ebbr.rst b/source/ebbr.rst index 7adcd0a..858bd01 100644 --- a/source/ebbr.rst +++ b/source/ebbr.rst @@ -198,9 +198,16 @@ Configuration Tables -------------------- A UEFI system that complies with this specification may provide the additional -tables via the EFI Configuration Table. -For example, ACPI table or Device Tree table may be needed to support -configuration and power management. +tables via the EFI Configuration Table. At a minimum, the system must provide +system data that conforms with either: + +- the Advanced Configuration and Power Interface specification[ACPI_], or +- the Devicetree Specification[DTSPEC_]. + +While a platform may provide either ACPI or Devicetree, it must not +provide both at the same time. Platforms that want to offer +both ACPI and Devicetree solutions must implement a boot time mechanism +to select one or the other before an OS Loader is executed. UEFI Secure Boot (Optional) --------------------------- @@ -524,6 +531,9 @@ EFI_ISCSI_INITIATOR_NAME_PROTOCOL 16.2 .. [ACPI] `Advanced Configuration and Power Interface specification v6.2A <http://www.uefi.org/sites/default/files/resources/ACPI%206_2_A_Sept29.pdf>`_, September 2017, `UEFI Forum <http://www.uefi.org>`_ +.. [DTSPEC] `Devicetree specification v0.2 + <https://github.com/devicetree-org/devicetree-specification/releases/tag/v0.2>`_, + `Devicetree.org <https://devicetree.org>`_ .. [PSCI] `Power State Coordination Interface Issue D (PSCI v1.1) <http://infocenter.arm.com/help//topic/com.arm.doc.den0022d/Power_State_Coordination_Interface_PDD_v1_1_DEN0022D.pdf>`_, 21 April 2017, `Arm Limited <http://arm.com>`_ -- 2.13.0 _______________________________________________ boot-architecture mailing list [email protected] https://lists.linaro.org/mailman/listinfo/boot-architecture
