xref: /linux/Documentation/devicetree/bindings/riscv/extensions.yaml (revision 6803bd7956ca8fc43069c2e42016f17f3c2fbf30)
1# SPDX-License-Identifier: (GPL-2.0 OR MIT)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/riscv/extensions.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: RISC-V ISA extensions
8
9maintainers:
10  - Paul Walmsley <paul.walmsley@sifive.com>
11  - Palmer Dabbelt <palmer@sifive.com>
12  - Conor Dooley <conor@kernel.org>
13
14description: |
15  RISC-V has a large number of extensions, some of which are "standard"
16  extensions, meaning they are ratified by RISC-V International, and others
17  are "vendor" extensions.
18  This document defines properties that indicate whether a hart supports a
19  given extension.
20
21  Once a standard extension has been ratified, no changes in behaviour can be
22  made without the creation of a new extension.
23  The properties for standard extensions therefore map to their originally
24  ratified states, with the exception of the I, Zicntr & Zihpm extensions.
25  See the "i" property for more information.
26
27select:
28  properties:
29    compatible:
30      contains:
31        const: riscv
32
33properties:
34  riscv,isa:
35    description:
36      Identifies the specific RISC-V instruction set architecture
37      supported by the hart.  These are documented in the RISC-V
38      User-Level ISA document, available from
39      https://riscv.org/specifications/
40
41      Due to revisions of the ISA specification, some deviations
42      have arisen over time.
43      Notably, riscv,isa was defined prior to the creation of the
44      Zicntr, Zicsr, Zifencei and Zihpm extensions and thus "i"
45      implies "zicntr_zicsr_zifencei_zihpm".
46
47      While the isa strings in ISA specification are case
48      insensitive, letters in the riscv,isa string must be all
49      lowercase.
50    $ref: /schemas/types.yaml#/definitions/string
51    pattern: ^rv(?:64|32)imaf?d?q?c?b?k?j?p?v?h?(?:[hsxz](?:[a-z])+)?(?:_[hsxz](?:[a-z])+)*$
52    deprecated: true
53
54  riscv,isa-base:
55    description:
56      The base ISA implemented by this hart, as described by the 20191213
57      version of the unprivileged ISA specification.
58    enum:
59      - rv32i
60      - rv64i
61
62  riscv,isa-extensions:
63    $ref: /schemas/types.yaml#/definitions/string-array
64    minItems: 1
65    description: Extensions supported by the hart.
66    items:
67      anyOf:
68        # single letter extensions, in canonical order
69        - const: i
70          description: |
71            The base integer instruction set, as ratified in the 20191213
72            version of the unprivileged ISA specification.
73
74            This does not include Chapter 10, "Counters", which was moved into
75            the Zicntr and Zihpm extensions after the ratification of the
76            20191213 version of the unprivileged specification.
77
78        - const: m
79          description:
80            The standard M extension for integer multiplication and division, as
81            ratified in the 20191213 version of the unprivileged ISA
82            specification.
83
84        - const: a
85          description:
86            The standard A extension for atomic instructions, as ratified in the
87            20191213 version of the unprivileged ISA specification.
88
89        - const: f
90          description:
91            The standard F extension for single-precision floating point, as
92            ratified in the 20191213 version of the unprivileged ISA
93            specification.
94
95        - const: d
96          description:
97            The standard D extension for double-precision floating-point, as
98            ratified in the 20191213 version of the unprivileged ISA
99            specification.
100
101        - const: q
102          description:
103            The standard Q extension for quad-precision floating-point, as
104            ratified in the 20191213 version of the unprivileged ISA
105            specification.
106
107        - const: c
108          description:
109            The standard C extension for compressed instructions, as ratified in
110            the 20191213 version of the unprivileged ISA specification.
111
112        - const: v
113          description:
114            The standard V extension for vector operations, as ratified
115            in-and-around commit 7a6c8ae ("Fix text that describes vfmv.v.f
116            encoding") of the riscv-v-spec.
117
118        - const: h
119          description:
120            The standard H extension for hypervisors as ratified in the 20191213
121            version of the privileged ISA specification.
122
123        # multi-letter extensions, sorted alphanumerically
124        - const: smaia
125          description: |
126            The standard Smaia supervisor-level extension for the advanced
127            interrupt architecture for machine-mode-visible csr and behavioural
128            changes to interrupts as frozen at commit ccbddab ("Merge pull
129            request #42 from riscv/jhauser-2023-RC4") of riscv-aia.
130
131        - const: smstateen
132          description: |
133            The standard Smstateen extension for controlling access to CSRs
134            added by other RISC-V extensions in H/S/VS/U/VU modes and as
135            ratified at commit a28bfae (Ratified (#7)) of riscv-state-enable.
136
137        - const: ssaia
138          description: |
139            The standard Ssaia supervisor-level extension for the advanced
140            interrupt architecture for supervisor-mode-visible csr and
141            behavioural changes to interrupts as frozen at commit ccbddab
142            ("Merge pull request #42 from riscv/jhauser-2023-RC4") of riscv-aia.
143
144        - const: sscofpmf
145          description: |
146            The standard Sscofpmf supervisor-level extension for count overflow
147            and mode-based filtering as ratified at commit 01d1df0 ("Add ability
148            to manually trigger workflow. (#2)") of riscv-count-overflow.
149
150        - const: sstc
151          description: |
152            The standard Sstc supervisor-level extension for time compare as
153            ratified at commit 3f9ed34 ("Add ability to manually trigger
154            workflow. (#2)") of riscv-time-compare.
155
156        - const: svinval
157          description:
158            The standard Svinval supervisor-level extension for fine-grained
159            address-translation cache invalidation as ratified in the 20191213
160            version of the privileged ISA specification.
161
162        - const: svnapot
163          description:
164            The standard Svnapot supervisor-level extensions for napot
165            translation contiguity as ratified in the 20191213 version of the
166            privileged ISA specification.
167
168        - const: svpbmt
169          description:
170            The standard Svpbmt supervisor-level extensions for page-based
171            memory types as ratified in the 20191213 version of the privileged
172            ISA specification.
173
174        - const: zba
175          description: |
176            The standard Zba bit-manipulation extension for address generation
177            acceleration instructions as ratified at commit 6d33919 ("Merge pull
178            request #158 from hirooih/clmul-fix-loop-end-condition") of
179            riscv-bitmanip.
180
181        - const: zbb
182          description: |
183            The standard Zbb bit-manipulation extension for basic bit-manipulation
184            as ratified at commit 6d33919 ("Merge pull request #158 from
185            hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
186
187        - const: zbc
188          description: |
189            The standard Zbc bit-manipulation extension for carry-less
190            multiplication as ratified at commit 6d33919 ("Merge pull request
191            #158 from hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
192
193        - const: zbs
194          description: |
195            The standard Zbs bit-manipulation extension for single-bit
196            instructions as ratified at commit 6d33919 ("Merge pull request #158
197            from hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
198
199        - const: zicbom
200          description:
201            The standard Zicbom extension for base cache management operations as
202            ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
203
204        - const: zicbop
205          description:
206            The standard Zicbop extension for cache-block prefetch instructions
207            as ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of
208            riscv-CMOs.
209
210        - const: zicboz
211          description:
212            The standard Zicboz extension for cache-block zeroing as ratified
213            in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
214
215        - const: zicntr
216          description:
217            The standard Zicntr extension for base counters and timers, as
218            ratified in the 20191213 version of the unprivileged ISA
219            specification.
220
221        - const: zicond
222          description:
223            The standard Zicond extension for conditional arithmetic and
224            conditional-select/move operations as ratified in commit 95cf1f9
225            ("Add changes requested by Ved during signoff") of riscv-zicond.
226
227        - const: zicsr
228          description: |
229            The standard Zicsr extension for control and status register
230            instructions, as ratified in the 20191213 version of the
231            unprivileged ISA specification.
232
233            This does not include Chapter 10, "Counters", which documents
234            special case read-only CSRs, that were moved into the Zicntr and
235            Zihpm extensions after the ratification of the 20191213 version of
236            the unprivileged specification.
237
238        - const: zifencei
239          description:
240            The standard Zifencei extension for instruction-fetch fence, as
241            ratified in the 20191213 version of the unprivileged ISA
242            specification.
243
244        - const: zihintpause
245          description:
246            The standard Zihintpause extension for pause hints, as ratified in
247            commit d8ab5c7 ("Zihintpause is ratified") of the riscv-isa-manual.
248
249        - const: zihpm
250          description:
251            The standard Zihpm extension for hardware performance counters, as
252            ratified in the 20191213 version of the unprivileged ISA
253            specification.
254
255        - const: ztso
256          description:
257            The standard Ztso extension for total store ordering, as ratified
258            in commit 2e5236 ("Ztso is now ratified.") of the
259            riscv-isa-manual.
260
261additionalProperties: true
262...
263