1 # SPDX-License-Identifier: (GPL-2.0 OR MIT)
4 $id: http://devicetree.org/schemas/riscv/extensions.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: RISC-V ISA extensions
10 - Paul Walmsley <paul.walmsley@sifive.com>
11 - Palmer Dabbelt <palmer@sifive.com>
12 - Conor Dooley <conor@kernel.org>
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
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.
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/
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".
47 While the isa strings in ISA specification are case
48 insensitive, letters in the riscv,isa string must be all
50 $ref: /schemas/types.yaml#/definitions/string
51 pattern: ^rv(?:64|32)imaf?d?q?c?b?k?j?p?v?h?(?:[hsxz](?:[a-z])+)?(?:_[hsxz](?:[a-z])+)*$
56 The base ISA implemented by this hart, as described by the 20191213
57 version of the unprivileged ISA specification.
63 $ref: /schemas/types.yaml#/definitions/string-array
65 description: Extensions supported by the hart.
68 # single letter extensions, in canonical order
71 The base integer instruction set, as ratified in the 20191213
72 version of the unprivileged ISA specification.
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.
80 The standard M extension for integer multiplication and division, as
81 ratified in the 20191213 version of the unprivileged ISA
86 The standard A extension for atomic instructions, as ratified in the
87 20191213 version of the unprivileged ISA specification.
91 The standard F extension for single-precision floating point, as
92 ratified in the 20191213 version of the unprivileged ISA
97 The standard D extension for double-precision floating-point, as
98 ratified in the 20191213 version of the unprivileged ISA
103 The standard Q extension for quad-precision floating-point, as
104 ratified in the 20191213 version of the unprivileged ISA
109 The standard C extension for compressed instructions, as ratified in
110 the 20191213 version of the unprivileged ISA specification.
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.
120 The standard H extension for hypervisors as ratified in the 20191213
121 version of the privileged ISA specification.
123 # multi-letter extensions, sorted alphanumerically
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.
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.
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.
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.
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.
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.
164 The standard Svnapot supervisor-level extensions for napot
165 translation contiguity as ratified in the 20191213 version of the
166 privileged ISA specification.
170 The standard Svpbmt supervisor-level extensions for page-based
171 memory types as ratified in the 20191213 version of the privileged
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
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.
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.
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.
201 The standard Zicbom extension for base cache management operations as
202 ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
206 The standard Zicbop extension for cache-block prefetch instructions
207 as ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of
212 The standard Zicboz extension for cache-block zeroing as ratified
213 in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
217 The standard Zicntr extension for base counters and timers, as
218 ratified in the 20191213 version of the unprivileged ISA
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.
229 The standard Zicsr extension for control and status register
230 instructions, as ratified in the 20191213 version of the
231 unprivileged ISA specification.
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.
240 The standard Zifencei extension for instruction-fetch fence, as
241 ratified in the 20191213 version of the unprivileged ISA
246 The standard Zihintpause extension for pause hints, as ratified in
247 commit d8ab5c7 ("Zihintpause is ratified") of the riscv-isa-manual.
251 The standard Zihpm extension for hardware performance counters, as
252 ratified in the 20191213 version of the unprivileged ISA
257 The standard Ztso extension for total store ordering, as ratified
258 in commit 2e5236 ("Ztso is now ratified.") of the
261 additionalProperties: true