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authorLinus Torvalds <torvalds@linux-foundation.org>2023-07-07 20:07:19 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2023-07-07 20:07:19 +0300
commit4f6b6c2b2f86b7878a770736bf478d8a263ff0bc (patch)
treec83b3755c1a14ffb571ce7ce49c9f74cb243a22d /Documentation
parent22dcc7d77fa463914bc2a2fb4580e6d183ca415d (diff)
parente8605e8fdf42642048b7e59141deaf8e4cf06d71 (diff)
downloadlinux-4f6b6c2b2f86b7878a770736bf478d8a263ff0bc.tar.xz
Merge tag 'riscv-for-linus-6.5-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull more RISC-V updates from Palmer Dabbelt: - A bunch of fixes/cleanups from the first part of the merge window, mostly related to ACPI and vector as those were large - Some documentation improvements, mostly related to the new code - The "riscv,isa" DT key is deprecated - Support for link-time dead code elimination - Support for minor fault registration in userfaultd - A handful of cleanups around CMO alternatives * tag 'riscv-for-linus-6.5-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (23 commits) riscv: mm: mark noncoherent_supported as __ro_after_init riscv: mm: mark CBO relate initialization funcs as __init riscv: errata: thead: only set cbom size & noncoherent during boot riscv: Select HAVE_ARCH_USERFAULTFD_MINOR RISC-V: Document the ISA string parsing rules for ACPI risc-v: Fix order of IPI enablement vs RCU startup mm: riscv: fix an unsafe pte read in huge_pte_alloc() dt-bindings: riscv: deprecate riscv,isa RISC-V: drop error print from riscv_hartid_to_cpuid() riscv: Discard vector state on syscalls riscv: move memblock_allow_resize() after linear mapping is ready riscv: Enable ARCH_SUSPEND_POSSIBLE for s2idle riscv: vdso: include vdso/vsyscall.h for vdso_data selftests: Test RISC-V Vector's first-use handler riscv: vector: clear V-reg in the first-use trap riscv: vector: only enable interrupts in the first-use trap RISC-V: Fix up some vector state related build failures RISC-V: Document that V registers are clobbered on syscalls riscv: disable HAVE_LD_DEAD_CODE_DATA_ELIMINATION for LLD riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/riscv/cpus.yaml43
-rw-r--r--Documentation/devicetree/bindings/riscv/extensions.yaml250
-rw-r--r--Documentation/riscv/acpi.rst10
-rw-r--r--Documentation/riscv/index.rst1
-rw-r--r--Documentation/riscv/vector.rst8
5 files changed, 289 insertions, 23 deletions
diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
index 67bd239ead0b..38c0b5213736 100644
--- a/Documentation/devicetree/bindings/riscv/cpus.yaml
+++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
@@ -25,6 +25,7 @@ description: |
allOf:
- $ref: /schemas/cpu.yaml#
+ - $ref: extensions.yaml
properties:
compatible:
@@ -82,25 +83,6 @@ properties:
description:
The blocksize in bytes for the Zicboz cache operations.
- riscv,isa:
- description:
- Identifies the specific RISC-V instruction set architecture
- supported by the hart. These are documented in the RISC-V
- User-Level ISA document, available from
- https://riscv.org/specifications/
-
- Due to revisions of the ISA specification, some deviations
- have arisen over time.
- Notably, riscv,isa was defined prior to the creation of the
- Zicntr, Zicsr, Zifencei and Zihpm extensions and thus "i"
- implies "zicntr_zicsr_zifencei_zihpm".
-
- While the isa strings in ISA specification are case
- insensitive, letters in the riscv,isa string must be all
- lowercase.
- $ref: /schemas/types.yaml#/definitions/string
- pattern: ^rv(?:64|32)imaf?d?q?c?b?k?j?p?v?h?(?:[hsxz](?:[a-z])+)?(?:_[hsxz](?:[a-z])+)*$
-
# RISC-V has multiple properties for cache op block sizes as the sizes
# differ between individual CBO extensions
cache-op-block-size: false
@@ -139,8 +121,17 @@ properties:
DMIPS/MHz, relative to highest capacity-dmips-mhz
in the system.
+anyOf:
+ - required:
+ - riscv,isa
+ - required:
+ - riscv,isa-base
+
+dependencies:
+ riscv,isa-base: [ "riscv,isa-extensions" ]
+ riscv,isa-extensions: [ "riscv,isa-base" ]
+
required:
- - riscv,isa
- interrupt-controller
unevaluatedProperties: false
@@ -160,7 +151,9 @@ examples:
i-cache-sets = <128>;
i-cache-size = <16384>;
reg = <0>;
- riscv,isa = "rv64imac";
+ riscv,isa-base = "rv64i";
+ riscv,isa-extensions = "i", "m", "a", "c";
+
cpu_intc0: interrupt-controller {
#interrupt-cells = <1>;
compatible = "riscv,cpu-intc";
@@ -183,8 +176,10 @@ examples:
i-tlb-size = <32>;
mmu-type = "riscv,sv39";
reg = <1>;
- riscv,isa = "rv64imafdc";
tlb-split;
+ riscv,isa-base = "rv64i";
+ riscv,isa-extensions = "i", "m", "a", "f", "d", "c";
+
cpu_intc1: interrupt-controller {
#interrupt-cells = <1>;
compatible = "riscv,cpu-intc";
@@ -202,8 +197,10 @@ examples:
device_type = "cpu";
reg = <0>;
compatible = "riscv";
- riscv,isa = "rv64imafdc";
mmu-type = "riscv,sv48";
+ riscv,isa-base = "rv64i";
+ riscv,isa-extensions = "i", "m", "a", "f", "d", "c";
+
interrupt-controller {
#interrupt-cells = <1>;
interrupt-controller;
diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
new file mode 100644
index 000000000000..cc1f546fdbdc
--- /dev/null
+++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
@@ -0,0 +1,250 @@
+# SPDX-License-Identifier: (GPL-2.0 OR MIT)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/riscv/extensions.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: RISC-V ISA extensions
+
+maintainers:
+ - Paul Walmsley <paul.walmsley@sifive.com>
+ - Palmer Dabbelt <palmer@sifive.com>
+ - Conor Dooley <conor@kernel.org>
+
+description: |
+ RISC-V has a large number of extensions, some of which are "standard"
+ extensions, meaning they are ratified by RISC-V International, and others
+ are "vendor" extensions.
+ This document defines properties that indicate whether a hart supports a
+ given extension.
+
+ Once a standard extension has been ratified, no changes in behaviour can be
+ made without the creation of a new extension.
+ The properties for standard extensions therefore map to their originally
+ ratified states, with the exception of the I, Zicntr & Zihpm extensions.
+ See the "i" property for more information.
+
+select:
+ properties:
+ compatible:
+ contains:
+ const: riscv
+
+properties:
+ riscv,isa:
+ description:
+ Identifies the specific RISC-V instruction set architecture
+ supported by the hart. These are documented in the RISC-V
+ User-Level ISA document, available from
+ https://riscv.org/specifications/
+
+ Due to revisions of the ISA specification, some deviations
+ have arisen over time.
+ Notably, riscv,isa was defined prior to the creation of the
+ Zicntr, Zicsr, Zifencei and Zihpm extensions and thus "i"
+ implies "zicntr_zicsr_zifencei_zihpm".
+
+ While the isa strings in ISA specification are case
+ insensitive, letters in the riscv,isa string must be all
+ lowercase.
+ $ref: /schemas/types.yaml#/definitions/string
+ pattern: ^rv(?:64|32)imaf?d?q?c?b?k?j?p?v?h?(?:[hsxz](?:[a-z])+)?(?:_[hsxz](?:[a-z])+)*$
+ deprecated: true
+
+ riscv,isa-base:
+ description:
+ The base ISA implemented by this hart, as described by the 20191213
+ version of the unprivileged ISA specification.
+ enum:
+ - rv32i
+ - rv64i
+
+ riscv,isa-extensions:
+ $ref: /schemas/types.yaml#/definitions/string-array
+ minItems: 1
+ description: Extensions supported by the hart.
+ items:
+ anyOf:
+ # single letter extensions, in canonical order
+ - const: i
+ description: |
+ The base integer instruction set, as ratified in the 20191213
+ version of the unprivileged ISA specification.
+
+ This does not include Chapter 10, "Counters", which was moved into
+ the Zicntr and Zihpm extensions after the ratification of the
+ 20191213 version of the unprivileged specification.
+
+ - const: m
+ description:
+ The standard M extension for integer multiplication and division, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: a
+ description:
+ The standard A extension for atomic instructions, as ratified in the
+ 20191213 version of the unprivileged ISA specification.
+
+ - const: f
+ description:
+ The standard F extension for single-precision floating point, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: d
+ description:
+ The standard D extension for double-precision floating-point, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: q
+ description:
+ The standard Q extension for quad-precision floating-point, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: c
+ description:
+ The standard C extension for compressed instructions, as ratified in
+ the 20191213 version of the unprivileged ISA specification.
+
+ - const: v
+ description:
+ The standard V extension for vector operations, as ratified
+ in-and-around commit 7a6c8ae ("Fix text that describes vfmv.v.f
+ encoding") of the riscv-v-spec.
+
+ - const: h
+ description:
+ The standard H extension for hypervisors as ratified in the 20191213
+ version of the privileged ISA specification.
+
+ # multi-letter extensions, sorted alphanumerically
+ - const: smaia
+ description: |
+ The standard Smaia supervisor-level extension for the advanced
+ interrupt architecture for machine-mode-visible csr and behavioural
+ changes to interrupts as frozen at commit ccbddab ("Merge pull
+ request #42 from riscv/jhauser-2023-RC4") of riscv-aia.
+
+ - const: ssaia
+ description: |
+ The standard Ssaia supervisor-level extension for the advanced
+ interrupt architecture for supervisor-mode-visible csr and
+ behavioural changes to interrupts as frozen at commit ccbddab
+ ("Merge pull request #42 from riscv/jhauser-2023-RC4") of riscv-aia.
+
+ - const: sscofpmf
+ description: |
+ The standard Sscofpmf supervisor-level extension for count overflow
+ and mode-based filtering as ratified at commit 01d1df0 ("Add ability
+ to manually trigger workflow. (#2)") of riscv-count-overflow.
+
+ - const: sstc
+ description: |
+ The standard Sstc supervisor-level extension for time compare as
+ ratified at commit 3f9ed34 ("Add ability to manually trigger
+ workflow. (#2)") of riscv-time-compare.
+
+ - const: svinval
+ description:
+ The standard Svinval supervisor-level extension for fine-grained
+ address-translation cache invalidation as ratified in the 20191213
+ version of the privileged ISA specification.
+
+ - const: svnapot
+ description:
+ The standard Svnapot supervisor-level extensions for napot
+ translation contiguity as ratified in the 20191213 version of the
+ privileged ISA specification.
+
+ - const: svpbmt
+ description:
+ The standard Svpbmt supervisor-level extensions for page-based
+ memory types as ratified in the 20191213 version of the privileged
+ ISA specification.
+
+ - const: zba
+ description: |
+ The standard Zba bit-manipulation extension for address generation
+ acceleration instructions as ratified at commit 6d33919 ("Merge pull
+ request #158 from hirooih/clmul-fix-loop-end-condition") of
+ riscv-bitmanip.
+
+ - const: zbb
+ description: |
+ The standard Zbb bit-manipulation extension for basic bit-manipulation
+ as ratified at commit 6d33919 ("Merge pull request #158 from
+ hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
+
+ - const: zbc
+ description: |
+ The standard Zbc bit-manipulation extension for carry-less
+ multiplication as ratified at commit 6d33919 ("Merge pull request
+ #158 from hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
+
+ - const: zbs
+ description: |
+ The standard Zbs bit-manipulation extension for single-bit
+ instructions as ratified at commit 6d33919 ("Merge pull request #158
+ from hirooih/clmul-fix-loop-end-condition") of riscv-bitmanip.
+
+ - const: zicbom
+ description:
+ The standard Zicbom extension for base cache management operations as
+ ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
+
+ - const: zicbop
+ description:
+ The standard Zicbop extension for cache-block prefetch instructions
+ as ratified in commit 3dd606f ("Create cmobase-v1.0.pdf") of
+ riscv-CMOs.
+
+ - const: zicboz
+ description:
+ The standard Zicboz extension for cache-block zeroing as ratified
+ in commit 3dd606f ("Create cmobase-v1.0.pdf") of riscv-CMOs.
+
+ - const: zicntr
+ description:
+ The standard Zicntr extension for base counters and timers, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: zicsr
+ description: |
+ The standard Zicsr extension for control and status register
+ instructions, as ratified in the 20191213 version of the
+ unprivileged ISA specification.
+
+ This does not include Chapter 10, "Counters", which documents
+ special case read-only CSRs, that were moved into the Zicntr and
+ Zihpm extensions after the ratification of the 20191213 version of
+ the unprivileged specification.
+
+ - const: zifencei
+ description:
+ The standard Zifencei extension for instruction-fetch fence, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: zihintpause
+ description:
+ The standard Zihintpause extension for pause hints, as ratified in
+ commit d8ab5c7 ("Zihintpause is ratified") of the riscv-isa-manual.
+
+ - const: zihpm
+ description:
+ The standard Zihpm extension for hardware performance counters, as
+ ratified in the 20191213 version of the unprivileged ISA
+ specification.
+
+ - const: ztso
+ description:
+ The standard Ztso extension for total store ordering, as ratified
+ in commit 2e5236 ("Ztso is now ratified.") of the
+ riscv-isa-manual.
+
+additionalProperties: true
+...
diff --git a/Documentation/riscv/acpi.rst b/Documentation/riscv/acpi.rst
new file mode 100644
index 000000000000..9870a282815b
--- /dev/null
+++ b/Documentation/riscv/acpi.rst
@@ -0,0 +1,10 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============
+ACPI on RISC-V
+==============
+
+The ISA string parsing rules for ACPI are defined by `Version ASCIIDOC
+Conversion, 12/2022 of the RISC-V specifications, as defined by tag
+"riscv-isa-release-1239329-2023-05-23" (commit 1239329
+) <https://github.com/riscv/riscv-isa-manual/releases/tag/riscv-isa-release-1239329-2023-05-23>`_
diff --git a/Documentation/riscv/index.rst b/Documentation/riscv/index.rst
index 95cf9c1e1da1..81cf6e616476 100644
--- a/Documentation/riscv/index.rst
+++ b/Documentation/riscv/index.rst
@@ -5,6 +5,7 @@ RISC-V architecture
.. toctree::
:maxdepth: 1
+ acpi
boot-image-header
vm-layout
hwprobe
diff --git a/Documentation/riscv/vector.rst b/Documentation/riscv/vector.rst
index 48f189d79e41..165b7ed0ac4f 100644
--- a/Documentation/riscv/vector.rst
+++ b/Documentation/riscv/vector.rst
@@ -130,3 +130,11 @@ processes in form of sysctl knob:
Modifying the system default enablement status does not affect the enablement
status of any existing process of thread that do not make an execve() call.
+
+3. Vector Register State Across System Calls
+---------------------------------------------
+
+As indicated by version 1.0 of the V extension [1], vector registers are
+clobbered by system calls.
+
+1: https://github.com/riscv/riscv-v-spec/blob/master/calling-convention.adoc