On 23/05/2018 19:12, Rob Herring wrote:
On Fri, May 18, 2018 at 8:06 AM, Grant Likely grant.likely@arm.com 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 grant.likely@arm.com
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
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.