04.10.2021 11:37, Krzysztof Kozlowski пишет:

On 03/10/2021 03:32, Dmitry Osipenko wrote:

quoted

Some Tegra20 boards don't have RAM code stored in NVMEM, which is used for
the memory chip identification and the identity information should be read
out from LPDDR2 chip in this case. Document new sub-node containing generic
LPDDR2 properties that will be used for the memory chip identification if
RAM code isn't available. The identification is done by reading out memory
configuration values from generic LPDDR2 mode registers of SDRAM chip and
comparing them with the values of device-tree sub-node's.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 .../memory-controllers/nvidia,tegra20-emc.yaml  | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.yaml b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.yaml
index cac6842dc8f1..65f7c3898ac4 100644
--- a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.yaml
+++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra20-emc.yaml

@@ -164,13 +164,14 @@ patternProperties:
       "#size-cells":
         const: 0
 
+      lpddr2-configuration:

Nodes should be named generic, so just lpddr2?

Yes

quoted

+        $ref: "jedec,lpddr2.yaml#"
+        type: object
+
     patternProperties:
       "^emc-table@[0-9]+$":
         $ref: "#/$defs/emc-table"
 
-    required:
-      - nvidia,ram-code

Isn't lpddr2-configuration required in such case? If not, probably you
want either this or that (oneOf like in reserved-memory.yaml).

Thanks, oneOf will work.