Merge pull request #1 from cmuellner/initial-specification

Initial specification

.gitignore

@@ -0,0 +1,5 @@
+*.pdf
+.asciidoctor
+images/diag-*
+revision.adoc-snippet*
+

Makefile

@@ -0,0 +1,31 @@
+SPEC=xthead
+HEADER_SOURCE := $(SPEC).adoc
+GITVER=$(shell git describe --tag --always --dirty)
+GITDATE=$(shell git show -s --format=%ci | cut -d ' ' -f 1)
+
+# e.g. "2022-07-29-d027732", or "2022-08-01-dbd4007-dirty"
+VERSION="$(GITDATE)-$(GITVER)"
+
+$(SPEC)-$(VERSION).pdf: *.adoc revision.adoc-snippet
+	@echo "Building asciidoc"
+	asciidoctor-pdf \
+		--attribute=mathematical-format=svg \
+		--attribute=pdf-fontsdir=resources/fonts \
+		--attribute=pdf-style=resources/themes/thead-pdf.yml \
+		--failure-level=ERROR \
+		--require=asciidoctor-diagram \
+		--require=asciidoctor-mathematical \
+		--out-file=$@ \
+		$(HEADER_SOURCE)
+
+.PHONY: revision.adoc-snippet
+revision.adoc-snippet:
+	echo ":revdate: ${GITDATE}" >> $@-tmp
+	echo ":revnumber: ${GITVER}" >> $@-tmp
+	diff $@ $@-tmp || mv $@-tmp $@
+
+all: $(SPEC)-$(VERSION).pdf
+
+clean:
+	rm -f $(SPEC)-*.pdf
+	rm -f revision.adoc-snippet*

README.md

@@ -1,2 +1,13 @@
-# thead-extension-spec
-T-head vendor extension Instruction Set spec
+# T-Head ISA extensions (Xthead*)
+
+This repository contains the T-Head RISC-V ISA extensions (Xthead*) specifications.
+
+## Build instructions
+
+The specification is written in AsciiDoc.
+The following instructions can be used to generate a PDF containing
+all specifications:
+
+```
+make
+```

docinfo.adoc

@@ -0,0 +1,35 @@
+== Document information
+
+=== Copyright and license information
+This specification is licensed under the Apache License, Version 2.0
+(Apache-2.0). The full license text is available at
+https://www.apache.org/licenses/LICENSE-2.0.
+
+Copyright 2022 T-Head Semiconductor Co., Ltd.
+
+Copyright 2022 VRULL GmbH
+
+=== Contributors
+
+The list below includes all contributors to this document in alphabetical order:
+
+[%hardbreaks]
+* Christoph Müllner <christoph.muellner@vrull.eu>
+* Cooper Qu <cooper.qu@linux.alibaba.com>
+* Lifang Xia <lifang_xia@linux.alibaba.com>
+* Philipp Tomsich <philipp.tomsich@vrull.eu>
+* Yunhai Shang < yunhai@linux.alibaba.com>
+* Zhiwei Liu <zhiwei_liu@linux.alibaba.com>
+
+=== Changelog
+
+* 2022-07-12: Initial draft with four CMO instructions
+* 2022-07-16: Adding complete XTheadCmo extension
+* 2022-07-20: Adding XTheadMemPair extension, adding HW requirements for XTheadCmo
+* 2022-07-26: Adding XTheadCmo U mode permission, Adding XTHeadSync, XTheadFMemIdx
+* 2022-07-27: Adding XTheadMemPair, XTheadMemIdx, XTheadMac, XThadCondMov, XTheadB[a,b,s]
+* 2022-07-29: Adding XTheadEE (mxstatus.theadisaee) and mxstatus.ucme (as part of XTheadCmo)
+* 2022-08-01: Remove XTheadEE and rework availability/permission documentation, adding lifecycle-states,
+              adding doc versioning and changelog
+* 2022-08-10: *.adoc: Fix several formatting issues
+* 2022-08-25: Adjusting contributors list

intro.adoc

@@ -0,0 +1,82 @@
+== Introduction
+
+The T-Head extension collection was created to augment
+the RISC-V ISA by adding additional functionality
+to enable faster and more energy-efficient solutions.
+
+The RISC-V ISA and its standardized extensions provide a rich set of
+instructions suitable for a wide range of applications, starting from
+specialized microcontrollers to HPC systems.
+The suitability for such a range of systems comes from the fact that
+the RISC-V ISA is modularized with a base instruction set and a range
+of extensions that target specific target applications and functionality.
+
+The RISC-V ISA and its authors strongly advertise the ability
+to create vendor extensions. Dedicated encoding spaces ensure,
+that there are not conflicts with standard extensions.
+
+This document specifies the T-Head extension collection,
+a collection of vendor extensions that are implemented
+in many T-Head processors.
+
+=== Overview
+
+The T-Head extension collection follows the principles of the RISC-V ISA.
+The collection consists of the following ISA extensions:
+
+* `XTheadCmo` provides instructions for cache management.
+* `XTheadSync` provides instructions for multi-processor synchronization.
+* `XTheadBa` provides instructions for address calculations.
+* `XTheadBb` provides instructions for basic bit-manipulation.
+* `XTheadBs` provides single-bit instructions.
+* `XTheadCondMov` provides instructions for conditional moves.
+* `XTheadMemIdx` provides GPR memory operations.
+* `XTheadMemPair` provides two-GP-register memory operations.
+* `XTheadFMemIdx` provides floating-point memory operations.
+* `XTheadMac` provides multiply-accumulate instructions.
+
+=== Dependencies to standard extensions
+
+The T-Head extension collection is designed to be compatible
+with RISC-V's base integer instruction sets RV32I and RV64I.
+
+Some instructions are only available if the system's
+`XLEN` is 64 (i.e. integer registers and supported user
+address space is 64 bits).
+To highlight the availability, each extension documents
+this for each instruction.
+
+Instruction that operate on floating-point registers can
+be used in combination with `F` (32-bit floating-point register)
+or `D` (64-bit floating-point registers).
+Some instruction are only available if the system implements
+the `D` extension. To highlight the availability, each
+floating-point extension document this for each instruction.
+
+=== Enablement of extensions and instructions
+
+All extensions and instructions are expected to be enabled at all times.
+The instructions can be used at any time when executing in the documented
+privilege levels, that permit the execution of the instruction.
+
+However, there might be SoC-specific mechanisms to ensure this behaviour.
+E.g. the T-Head C906 requires the CSR field `mxstatus.theadisaee` to
+be set to `1` to enable the ISA extensions.
+Another example is the CSR field `mxstatus.ucme` of the T-Head C906,
+that is required to be set to `1` in order to execute cache management
+instructions in `U` mode (if the instruction is documented that this
+is permitted).
+
+=== Lifecycle
+
+The lifecycle of the extensions included in this document is
+defined on a per-extension base.
+
+Possible states are:
+
+* `Draft`: No guarantees (everything may change).
+* `Stable`: No feature additions/removals/changes. Only clarifications.
+
+A `draft` specification is expected to become `stable` in the future
+(with exepcted changes until then). A `stable` extension remains in that
+state for ever.

resources/fonts/OFL-M.txt

@@ -0,0 +1,93 @@
+Copyright 2011 The Montserrat Project Authors (https://github.com/JulietaUla/Montserrat)
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.

resources/fonts/OFL-P.txt

@@ -0,0 +1,93 @@
+Copyright 2019 The Petrona Project Authors (https://github.com/RingoSeeber/Petrona)
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.