On 23/05/2018 19:12, Rob Herring wrote:
On Fri, May 18, 2018 at 8:06 AM, Grant Likely <[email protected]> wrote:
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>`_,
Do we really want the exact version that we have to update? Also, it
is not like 0.2 version of the spec is in anyway a complete
representation of DT requirements. You can link to
.../releases/latest/ BTW. OTOH, the version doesn't change that often.
Yes, I think we do. A release of a spec like this is built on specific
versions (or higher) of the specs it references. I put in v0.2 just
because that is what we have right now. If we can get a new DT spec out
before EBBR is released, then this should be updated.
g.
_______________________________________________
boot-architecture mailing list
[email protected]
https://lists.linaro.org/mailman/listinfo/boot-architecture
