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authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-24 15:16:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-24 15:16:46 -0700
commite7bd3e248bc36451fdbf2a2e3a3c5a23cd0b1f6f (patch)
tree3d64fa8c37300561936ddbb0b17ab3a0cc71a365 /Documentation/devicetree/bindings/sifive/sifive-blocks-ip-versioning.txt
parent86c2f5d653058798703549e1be39a819fcac0d5d (diff)
parent852d095d16a6298834839f441593f59d58a31978 (diff)
Merge tag 'devicetree-fixes-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull Devicetree fixes from Rob Herring: - Update checkpatch.pl to use DT vendor-prefixes.yaml - Fix DT binding references to files converted to DT schema - Clean-up Arm CPU binding examples to match schema - Add Sifive block versioning scheme documentation - Pass binding directory base to validation tools for reference lookups * tag 'devicetree-fixes-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: checkpatch.pl: Update DT vendor prefix check dt: bindings: mtd: replace references to nand.txt with nand-controller.yaml dt-bindings: interrupt-controller: arm,gic: Fix schema errors in example dt-bindings: arm: Clean up CPU binding examples dt: fix refs that were renamed to json with the same file name dt-bindings: Pass binding directory to validation tools dt-bindings: sifive: describe sifive-blocks versioning
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+DT compatible string versioning for SiFive open-source IP blocks
+
+This document describes the version specification for DT "compatible"
+strings for open-source SiFive IP blocks. HDL for these IP blocks
+can be found in this public repository:
+
+https://github.com/sifive/sifive-blocks
+
+IP block-specific DT compatible strings are contained within the HDL,
+in the form "sifive,<ip-block-name><integer version number>".
+
+An example is "sifive,uart0" from:
+
+https://github.com/sifive/sifive-blocks/blob/v1.0/src/main/scala/devices/uart/UART.scala#L43
+
+Until these IP blocks (or IP integration) support version
+auto-discovery, the maintainers of these IP blocks intend to increment
+the suffixed number in the compatible string whenever the software
+interface to these IP blocks changes, or when the functionality of the
+underlying IP blocks changes in a way that software should be aware of.
+
+Driver developers can use compatible string "match" values such as
+"sifive,uart0" to indicate that their driver is compatible with the
+register interface and functionality associated with the relevant
+upstream sifive-blocks commits. It is expected that most drivers will
+match on these IP block-specific compatible strings.
+
+DT data authors, when writing data for a particular SoC, should
+continue to specify an SoC-specific compatible string value, such as
+"sifive,fu540-c000-uart". This way, if SoC-specific
+integration-specific bug fixes or workarounds are needed, the kernel
+or other system software can match on this string to apply them. The
+IP block-specific compatible string (such as "sifive,uart0") should
+then be specified as a subsequent value.
+
+An example of this style:
+
+ compatible = "sifive,fu540-c000-uart", "sifive,uart0";