On Thu, 2015-05-21 at 14:34 -0700, Dan Williams wrote: > On Thu, May 21, 2015 at 1:59 PM, Linda Knippers <linda.knipp...@hp.com> wrote: > > On 05/21/2015 03:59 PM, Toshi Kani wrote: : > > > > I've lost track of the right answer but should we be discussing > > it in the context of this patch too? > > > > http://www.spinics.net/lists/linux-acpi/msg57825.html > > [PATCH 18/19] ACPICA: ACPI 6.0: Add support for NFIT table. > > > > Dan's version of the file has lots of other UUIDs too, beyond NFIT. > > Yeah, it's not clear whether those other GUIDs are actually GUIDs or > these byte-swapped "EFI GUID"s. At least for NFIT it seems that the > intent was EFI GUID ordering due to the note about needing to match > the "Disk Type GUID" format from the EFI spec. > > I circle back with the ACPICA folks.
Endianness only matters when you store GUID data into memory (or read it from memory). The data values themselves are independent from the endianness. GUIDs, EFI GUIDs, and their text strings all represent actual data values, and therefore no swapping is necessary. When storing EFI GUID or text string into memory/Buffer, EFI spec defines to store it in little-endian format. This is handled by EFI_GUID() macro for EFI GUID values, and ToUUID / acpi_str_to_uuid() for a string. Thanks, -Toshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
