EBBR platforms are unlikely to ever use the MP Start protocol used in some AArch64 server systems. It was only used to support platforms without EL3. No more EL2-only platforms are expected, and MP Start is being removed from the next release of SBBR. Devicetree platforms in the same scenario use the Linux spin table protocol instead.

MP Start was only included for completeness to align the SBBR and EBBR specifications. Therefore remove it entirely, leaving PSCI and spin table as the only acceptable implementations.

Also revert to PSCI v1.0 as that is the minimum level of functionality required. PSCI v1.1 adds new capabilities, but is not required for interoperability.

Suggested-by: Dong Wei dong.wei@arm.com Signed-off-by: Grant Likely grant.likely@arm.com --- source/ebbr.rst | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/source/ebbr.rst b/source/ebbr.rst index 40f03f1..4100b2f 100644 --- a/source/ebbr.rst +++ b/source/ebbr.rst @@ -329,10 +329,9 @@ Power State Coordination Interface specification[PSCI_]. Platforms without EL3 must implement one of:

- PSCI at EL2 (leaving only EL1 available to an operating system) -- MP Startup for Arm[MPSTART_] (ACPI Parking Protocol) on an ACPI platform -- Linux AArch64 spin tables[LINUXA64BOOT_] on a Devicetree platform +- Linux AArch64 spin tables[LINUXA64BOOT_] (Devicetree only)

-However, the MP Startup and Spintable protocols are strongly discouraged. +However, the spin table protocol is strongly discouraged. Future versions of this specification will only allow PSCI, and PSCI should be implemented in all new designs.

@@ -575,13 +574,9 @@ EFI_ISCSI_INITIATOR_NAME_PROTOCOL 16.2 https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/Documentation/arm64/booting.txt`_, Linux kernel

-.. [MPSTART] `MP Startup for Arm - https://acpica.org/sites/acpica/files/MP%20Startup%20for%20ARM%20platforms.doc`_, - 20 December 2012, `Microsoft http://microsoft.com`_ - -.. [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`_ +.. [PSCI] `Power State Coordination Interface Issue C (PSCI v1.0) + https://static.docs.arm.com/den0022/c/DEN0022C_Power_State_Coordination_Interface.pdf`_ + 30 January 2015, `Arm Limited http://arm.com`_

.. [SBBR] `Arm Server Base Boot Requirements specification Issue B (v1.0) https://static.docs.arm.com/den0044/b/DEN0044B_Server_Base_Boot_Requirements.pdf`_