dt-bindings: ddr: Add optional manufacturer and revision ID to LPDDR3

On some platforms, DDR parts are multi-sourced and the exact part number
used is not know to either kernel or firmware at build time. Firmware
can read identifying information from DDR mode registers at boot time
but needs a way to communicate this information to kernel and/or
userspace. This patch adds optional properties for this information to
the existing "jedec,lpddr3" device tree binding to be used for that
purpose.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Link: https://lore.kernel.org/r/20210324010405.1917577-1-jwerner@chromium.org
Signed-off-by: Rob Herring <robh@kernel.org>

diff --git a/Documentation/devicetree/bindings/ddr/lpddr3.txt b/Documentation/devicetree/bindings/ddr/lpddr3.txt
index a0eda35a86eef91fa57e300240301ff817a92653..b221e653d3845efcc13db8f72b3091ca730ff9e2 100644 (file)
--- a/Documentation/devicetree/bindings/ddr/lpddr3.txt
+++ b/Documentation/devicetree/bindings/ddr/lpddr3.txt
@@ -12,6 +12,9 @@ Required properties:
 
 Optional properties:
 
+- manufacturer-id : <u32>     Manufacturer ID value read from Mode Register 5
+- revision-id     : <u32 u32> Revision IDs read from Mode Registers 6 and 7
+
 The following optional properties represent the minimum value of some AC
 timing parameters of the DDR device in terms of number of clock cycles.
 These values shall be obtained from the device data-sheet.
@@ -49,6 +52,8 @@ samsung_K3QF2F20DB: lpddr3 {
        compatible      = "samsung,K3QF2F20DB", "jedec,lpddr3";
        density         = <16384>;
        io-width        = <32>;
+       manufacturer-id = <1>;
+       revision-id     = <123 234>;
        #address-cells  = <1>;
        #size-cells     = <0>;