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
  ...

Author: torvalds

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;

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 <[email protected]>
+  - Palmer Dabbelt <[email protected]>
+  - Conor Dooley <[email protected]>
+
+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
+...

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>`_

Documentation/riscv/index.rst

@@ -5,6 +5,7 @@ RISC-V architecture
 .. toctree::
     :maxdepth: 1
 
+    acpi
     boot-image-header
     vm-layout
     hwprobe

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