[RFC v1] dt-bindings: add IP versioning document for Microchip FPGAs

[Conor Dooley <conor@kernel.org>]

From: Conor Dooley <conor.dooley@microchip.com>

This is a pretty rough document I conjured up in 5 minutes, to document
my expectations for compatible strings for both our FPGA IP blocks and
reference designs that we ship, a la the one that exists for SiFive IPs.
There's been some internal conversations lately about this naming etc,
so good to have something written down.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
cc: cyril.jean@microchip.com
CC: valentina.fernandezalanis@microchip.com
CC: nitin.deshpande@microchip.com
CC: Rob Herring <robh@kernel.org>
CC: Krzysztof Kozlowski <krzk+dt@kernel.org>
CC: Conor Dooley <conor+dt@kernel.org>
CC: devicetree@vger.kernel.org
CC: linux-kernel@vger.kernel.org
---
 .../bindings/microchip/ip-versioning.txt      | 34 +++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/microchip/ip-versioning.txt

diff --git a/Documentation/devicetree/bindings/microchip/ip-versioning.txt b/Documentation/devicetree/bindings/microchip/ip-versioning.txt
new file mode 100644
index 000000000000..4a4e0e74c4e6
--- /dev/null
+++ b/Documentation/devicetree/bindings/microchip/ip-versioning.txt
@@ -0,0 +1,34 @@
+Devicetree compatible string versioning for Microchip FPGA IP blocks and reference designs
+
+This document describes the versioning guidelines for compatible strings
+used on Microchip FPGA IP blocks and reference designs.
+
+IP block-specific compatible strings are in the form:
+"microchip,<ip-block-name>-rtl-v<major version number>"
+or optionally:
+"microchip,<ip-block-name>-rtl-v<major version number>.<minor version number>"
+
+<ip-block-name> should be the name of the IP in Libero's IP catalog.
+In most cases a major version should be sufficient, as breaking changes are
+intended to be accompanied by a version update, but if not, the optional minor
+version should be used,
+
+An example is:
+  compatible = "microchip,corei2c-rtl-v7";
+
+If the IP is integrated as a "hard" peripheral in an SoC, the expectation is
+that there will be a fallback to the IP block it was derived from, if
+appropriate, such as:
+  compatible = "microchip,mpfs-i2c", "microchip,corei2c-rtl-v7";
+
+The versioning scheme for reference designs that Microchip provides for its
+development kits is similar:
+"microchip,<soc>-<board>-reference-rtl-v<yymm>".
+
+This should be followed by a fallback compatible belonging to the board itself:
+"microchip,<soc>-<board>"
+and then one for the soc:
+"microchip,<soc>"
+
+For example:
+  compatible = "microchip,mpfs-icicle-reference-rtl-v2210", "microchip,mpfs-icicle-kit", "microchip,mpfs";
-- 
2.45.2