UEFI spec is adding ability for all runtime services to return EFI_UNSUPPORTED if not implemented. Use this return code instead of EFI_DEVICE_ERROR.
Resolves: #14 Signed-off-by: Grant Likely grant.likely@arm.com --- source/chapter2-uefi.rst | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/source/chapter2-uefi.rst b/source/chapter2-uefi.rst index 6f7d260..239fd8c 100644 --- a/source/chapter2-uefi.rst +++ b/source/chapter2-uefi.rst @@ -151,9 +151,9 @@ it may not be possible to access the RTC from runtime services. e.g., The RTC may be on a shared I2C bus which runtime services cannot access because it will conflict with the OS.
-Firmware still must provide the UEFI GetTime() and SetTime() runtime service -calls, but if an RTC isn't present, or cannot be accessed at runtime, then both -calls shall return EFI_DEVICE_ERROR. +If firmware does not support access to the RTC, then GetTime() and +SetTime() shall return EFI_UNSUPPORTED, +and the OS must use a device driver to control the RTC.
UEFI Reset and Shutdown -----------------------