On 08.03.2021 22:37, Rafał Miłecki wrote:
On 08.03.2021 19:43, Rob Herring wrote:
On Tue, Mar 02, 2021 at 08:44:04AM +0100, Rafał Miłecki wrote:
From: Rafał Miłecki <rafal@xxxxxxxxxx>
NVRAM structure contains device data and can be accessed using MMIO.
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
.../bindings/firmware/brcm,nvram.yaml | 41 +++++++++++++++++++
1 file changed, 41 insertions(+)
create mode 100644 Documentation/devicetree/bindings/firmware/brcm,nvram.yaml
diff --git a/Documentation/devicetree/bindings/firmware/brcm,nvram.yaml b/Documentation/devicetree/bindings/firmware/brcm,nvram.yaml
new file mode 100644
index 000000000000..12af8e2e7c9c
--- /dev/null
+++ b/Documentation/devicetree/bindings/firmware/brcm,nvram.yaml
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/firmware/brcm,nvram.yaml#";
+$schema: "http://devicetree.org/meta-schemas/core.yaml#";
+
+title: Broadcom's NVRAM
+
+maintainers:
+ - Rafał Miłecki <rafal@xxxxxxxxxx>
+
+description: |
+ NVRAM is a structure containing device specific environment variables.
+ It is used for storing device configuration, booting parameters and
+ calibration data.
The structure of the data is fully discoverable just from a genericish
'brcm,nvram'?
Yes, NVRAM structure is a header (with magic and length) and a list of
key-value pairs separated by \0. If you map memory at given address you
should verify magic and start reading key-value pairs.
Content example: foo=bar\0baz=qux\0quux(...)
There is no predefined order of pairs, set of keys or anything similar I
could think of. I can't think of anything more worth describing in DT.
Ah, I've just realized, I'm replying to the "firmware" binding patch.
Florian suggested to look at NVMEM subsystem instead. Please kindly check
[PATCH V2 1/2] dt-bindings: nvmem: add Broadcom's NVRAM
