dt-bindings: firmware: coreboot: document board variant
From: Heiko Stuebner <heiko@...> Date: Fri, 3 Aug 2018 14:39:45 +0200
Commit-Message
Since at least 2014 coreboot exports board specific variant ids for board-revision, used ram-modules and component variants on the same board into the loaded devicetree. These are set on all devicetree-based Chromebooks since then, so at least we can make the effort to document these long-used properties. A case where these are used is for example to determine the touchscreen type that is only identifyable via the sku-id when updating its firmware on the Scarlet tablet from the Gru ChromeOS family. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
Documentation/devicetree/bindings/firmware/coreboot.txt | 6 ++++++ 1 file changed, 6 insertions(+)
Statistics
- 6 lines added
- 0 lines removed
Changes
----------- Documentation/devicetree/bindings/firmware/coreboot.txt ------------
index 4c955703cea8..cfc7623e2577 100644
@@ -21,6 +21,12 @@ Required properties:
0xc0389481 that resides in the topmost 8 bytes of the area.
See coreboot's src/include/imd.h for details.
+Board variant properties determined via strapping measures (like gpios):
+ - board-id: board-specific id indicating the board-revision
+ - ram-code: board-specific id identifying the used ram-module
+ - sku-id: board-specific id indicating a variant (using different
+ display panels for example)
+
Example:
firmware {
ranges;