At the Linaro Connect Face to Face meeting the requirements on runtime
services were discussed. It was agreed to propose a change to UEFI that
allows all EFI_RUNTIME_SERVICE functions to return EFI_UNSUPPORTED
during runtime services. Rework the text to reflect those decisions and
the UEFI ECR.
Signed-off-by: Grant Likely <grant.lik...@arm.com>
---
source/appendix-a-uefi-features.rst | 27 ---------------------
source/chapter2-uefi.rst | 47 +++++++++++++++++++++++++++----------
source/index.rst | 2 ++
3 files changed, 37 insertions(+), 39 deletions(-)
diff --git a/source/appendix-a-uefi-features.rst
b/source/appendix-a-uefi-features.rst
index 8777edd..bb74ca5 100644
--- a/source/appendix-a-uefi-features.rst
+++ b/source/appendix-a-uefi-features.rst
@@ -56,33 +56,6 @@ EFI_SET_MEM 7.5
EFI_CREATE_EVENT_EX 7.5
========================================== ======
-.. _appendix-uefi-required-runtime:
-
-Required Runtime Services
-*************************
-
-========================================== ======
-Service UEFI ยง
-========================================== ======
-EFI_GET_TIME 8.3
-EFI_SET_TIME 8.3
-EFI_GET_WAKEUP_TIME 8.3
-EFI_SET_WAKEUP_TIME 8.3
-EFI_SET_VIRTUAL_ADDRESS_MAP 8.4
-EFI_CONVERT_POINTER 8.4
-EFI_GET_VARIABLE 8.2
-EFI_GET_NEXT_VARIABLE_NAME 8.2
-EFI_SET_VARIABLE 8.2
-EFI_GET_NEXT_HIGH_MONO_COUNT 8.5
-EFI_RESET_SYSTEM 8.5
-EFI_UPDATE_CAPSULE 8.5
-EFI_QUERY_CAPSULE_CAPABILITIES 8.5
-EFI_QUERY_VARIABLE_INFO 8.5
-========================================== ======
-
-.. note:: EFI_GET_WAKEUP_TIME and EFI_SET_WAKEUP_TIME must be implemented, but
- might simply return EFI_UNSUPPORTED.
-
Required UEFI Protocols
***********************
diff --git a/source/chapter2-uefi.rst b/source/chapter2-uefi.rst
index a6b3ff7..cbf1529 100644
--- a/source/chapter2-uefi.rst
+++ b/source/chapter2-uefi.rst
@@ -110,20 +110,43 @@ requirements for Secure Boot.
UEFI Runtime Services
=====================
-UEFI Runtime Services exist after the call to ExitBootServices() and are
+UEFI runtime services exist after the call to ExitBootServices() and are
designed to provide a limited set of persistent services to the platform
Operating System or hypervisor.
-
-The Runtime Services that are listed in :ref:`appendix-uefi-required-runtime`
-must be provided.
-
-Runtime Exception Level
------------------------
-
-On AArch64, UEFI 2.7 enables runtime services to be supported at either
-EL1 or EL2, with appropriate virtual address mappings.
-When called, subsequent runtime service calls must be from the same Exception
-level.
+Functions contained in EFI_RUNTIME_SERVICES are expected to be available
+during both boot services and runtime services.
+However, it isn't always practical for all EFI_RUNTIME_SERVICES functions
+to be callable during runtime services due to hardware limitations.
+If any EFI_RUNTIME_SERVICES functions are only available during boot services
+then firmware shall provide the global `RuntimeServicesAvailable` variable to
+indicate which functions are available during runtime services.
+Functions that are not available during runtime services shall return
+EFI_UNSUPPORTED.
+
+Table :numref:_uefi_runtime_service_requirements details which
EFI_RUNTIME_SERVICES
+are required to be implemented during boot services and runtime services.
+
+.. _uefi_runtime_service_requirements:
+.. table:: EFI_RUNTIME_SERVICES Implementation Requirements
+
+ ============================== ============= ================
+ EFI_RUNTIME_SERVICES function Boot Services Runtime Services
+ ============================== ============= ================
+ EFI_GET_TIME Optional Optional
+ EFI_SET_TIME Optional Optional
+ EFI_GET_WAKEUP_TIME Optional Optional
+ EFI_SET_WAKEUP_TIME Optional Optional
+ EFI_SET_VIRTUAL_ADDRESS_MAP N/A Required
+ EFI_CONVERT_POINTER N/A Required
+ EFI_GET_VARIABLE Required Optional
+ EFI_GET_NEXT_VARIABLE_NAME Required Optional
+ EFI_SET_VARIABLE Required Optional
+ EFI_GET_NEXT_HIGH_MONO_COUNT N/A Optional
+ EFI_RESET_SYSTEM Required Optional
+ EFI_UPDATE_CAPSULE Optional Optional
+ EFI_QUERY_CAPSULE_CAPABILITIES Optional Optional
+ EFI_QUERY_VARIABLE_INFO Optional Optional
+ ============================== ============= ================
Runtime Device Mappings
-----------------------
diff --git a/source/index.rst b/source/index.rst
index db47ce6..3045387 100644
--- a/source/index.rst
+++ b/source/index.rst
@@ -37,6 +37,8 @@ Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
- Add large note on implementation of runtime
modification of non-volatile variables
TBD TBD - Add AArch32 details
+ - Refactor Runtime Services text after face
+ to fact meeting at Linaro Connect YVR18
================= ========= =============================================
.. toctree::
--
2.13.0
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