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authorLinus Torvalds <torvalds@linux-foundation.org>2024-03-14 15:35:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-03-14 15:35:42 -0700
commit6d75c6f40a03c97e1ecd683ae54e249abb9d922b (patch)
tree504f99c3a9854dbf64d1112c2fe09a9992c92b39 /Documentation/arch
parentfe46a7dd189e25604716c03576d05ac8a5209743 (diff)
parent1ef21fcd6a50f011680dbbd678c1bea8e3f67ab9 (diff)
downloadlinux-6d75c6f40a03c97e1ecd683ae54e249abb9d922b.tar.gz
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas: "The major features are support for LPA2 (52-bit VA/PA with 4K and 16K pages), the dpISA extension and Rust enabled on arm64. The changes are mostly contained within the usual arch/arm64/, drivers/perf, the arm64 Documentation and kselftests. The exception is the Rust support which touches some generic build files. Summary: - Reorganise the arm64 kernel VA space and add support for LPA2 (at stage 1, KVM stage 2 was merged earlier) - 52-bit VA/PA address range with 4KB and 16KB pages - Enable Rust on arm64 - Support for the 2023 dpISA extensions (data processing ISA), host only - arm64 perf updates: - StarFive's StarLink (integrates one or more CPU cores with a shared L3 memory system) PMU support - Enable HiSilicon Erratum 162700402 quirk for HIP09 - Several updates for the HiSilicon PCIe PMU driver - Arm CoreSight PMU support - Convert all drivers under drivers/perf/ to use .remove_new() - Miscellaneous: - Don't enable workarounds for "rare" errata by default - Clean up the DAIF flags handling for EL0 returns (in preparation for NMI support) - Kselftest update for ptrace() - Update some of the sysreg field definitions - Slight improvement in the code generation for inline asm I/O accessors to permit offset addressing - kretprobes: acquire regs via a BRK exception (previously done via a trampoline handler) - SVE/SME cleanups, comment updates - Allow CALL_OPS+CC_OPTIMIZE_FOR_SIZE with clang (previously disabled due to gcc silently ignoring -falign-functions=N)" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (134 commits) Revert "mm: add arch hook to validate mmap() prot flags" Revert "arm64: mm: add support for WXN memory translation attribute" Revert "ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512" ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512 kselftest/arm64: Add 2023 DPISA hwcap test coverage kselftest/arm64: Add basic FPMR test kselftest/arm64: Handle FPMR context in generic signal frame parser arm64/hwcap: Define hwcaps for 2023 DPISA features arm64/ptrace: Expose FPMR via ptrace arm64/signal: Add FPMR signal handling arm64/fpsimd: Support FEAT_FPMR arm64/fpsimd: Enable host kernel access to FPMR arm64/cpufeature: Hook new identification registers up to cpufeature docs: perf: Fix build warning of hisi-pcie-pmu.rst perf: starfive: Only allow COMPILE_TEST for 64-bit architectures MAINTAINERS: Add entry for StarFive StarLink PMU docs: perf: Add description for StarFive's StarLink PMU dt-bindings: perf: starfive: Add JH8100 StarLink PMU perf: starfive: Add StarLink PMU support docs: perf: Update usage for target filter of hisi-pcie-pmu ...
Diffstat (limited to 'Documentation/arch')
-rw-r--r--Documentation/arch/arm64/elf_hwcaps.rst49
-rw-r--r--Documentation/arch/arm64/silicon-errata.rst5
-rw-r--r--Documentation/arch/arm64/sme.rst11
-rw-r--r--Documentation/arch/arm64/sve.rst10
4 files changed, 59 insertions, 16 deletions
diff --git a/Documentation/arch/arm64/elf_hwcaps.rst b/Documentation/arch/arm64/elf_hwcaps.rst
index ced7b335e2e00..448c1664879bc 100644
--- a/Documentation/arch/arm64/elf_hwcaps.rst
+++ b/Documentation/arch/arm64/elf_hwcaps.rst
@@ -317,6 +317,55 @@ HWCAP2_LRCPC3
HWCAP2_LSE128
Functionality implied by ID_AA64ISAR0_EL1.Atomic == 0b0011.
+HWCAP2_FPMR
+ Functionality implied by ID_AA64PFR2_EL1.FMR == 0b0001.
+
+HWCAP2_LUT
+ Functionality implied by ID_AA64ISAR2_EL1.LUT == 0b0001.
+
+HWCAP2_FAMINMAX
+ Functionality implied by ID_AA64ISAR3_EL1.FAMINMAX == 0b0001.
+
+HWCAP2_F8CVT
+ Functionality implied by ID_AA64FPFR0_EL1.F8CVT == 0b1.
+
+HWCAP2_F8FMA
+ Functionality implied by ID_AA64FPFR0_EL1.F8FMA == 0b1.
+
+HWCAP2_F8DP4
+ Functionality implied by ID_AA64FPFR0_EL1.F8DP4 == 0b1.
+
+HWCAP2_F8DP2
+ Functionality implied by ID_AA64FPFR0_EL1.F8DP2 == 0b1.
+
+HWCAP2_F8E4M3
+ Functionality implied by ID_AA64FPFR0_EL1.F8E4M3 == 0b1.
+
+HWCAP2_F8E5M2
+ Functionality implied by ID_AA64FPFR0_EL1.F8E5M2 == 0b1.
+
+HWCAP2_SME_LUTV2
+ Functionality implied by ID_AA64SMFR0_EL1.LUTv2 == 0b1.
+
+HWCAP2_SME_F8F16
+ Functionality implied by ID_AA64SMFR0_EL1.F8F16 == 0b1.
+
+HWCAP2_SME_F8F32
+ Functionality implied by ID_AA64SMFR0_EL1.F8F32 == 0b1.
+
+HWCAP2_SME_SF8FMA
+ Functionality implied by ID_AA64SMFR0_EL1.SF8FMA == 0b1.
+
+HWCAP2_SME_SF8DP4
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP4 == 0b1.
+
+HWCAP2_SME_SF8DP2
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP2 == 0b1.
+
+HWCAP2_SME_SF8DP4
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP4 == 0b1.
+
+
4. Unused AT_HWCAP bits
-----------------------
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst
index 45a7f4932fe07..d33e27c5ce610 100644
--- a/Documentation/arch/arm64/silicon-errata.rst
+++ b/Documentation/arch/arm64/silicon-errata.rst
@@ -35,8 +35,9 @@ can be triggered by Linux).
For software workarounds that may adversely impact systems unaffected by
the erratum in question, a Kconfig entry is added under "Kernel
Features" -> "ARM errata workarounds via the alternatives framework".
-These are enabled by default and patched in at runtime when an affected
-CPU is detected. For less-intrusive workarounds, a Kconfig option is not
+With the exception of workarounds for errata deemed "rare" by Arm, these
+are enabled by default and patched in at runtime when an affected CPU is
+detected. For less-intrusive workarounds, a Kconfig option is not
available and the code is structured (preferably with a comment) in such
a way that the erratum will not be hit.
diff --git a/Documentation/arch/arm64/sme.rst b/Documentation/arch/arm64/sme.rst
index 3d0e53ecac4fe..be317d4574174 100644
--- a/Documentation/arch/arm64/sme.rst
+++ b/Documentation/arch/arm64/sme.rst
@@ -75,7 +75,7 @@ model features for SME is included in Appendix A.
2. Vector lengths
------------------
-SME defines a second vector length similar to the SVE vector length which is
+SME defines a second vector length similar to the SVE vector length which
controls the size of the streaming mode SVE vectors and the ZA matrix array.
The ZA matrix is square with each side having as many bytes as a streaming
mode SVE vector.
@@ -238,12 +238,12 @@ prctl(PR_SME_SET_VL, unsigned long arg)
bits of Z0..Z31 except for Z0 bits [127:0] .. Z31 bits [127:0] to become
unspecified, including both streaming and non-streaming SVE state.
Calling PR_SME_SET_VL with vl equal to the thread's current vector
- length, or calling PR_SME_SET_VL with the PR_SVE_SET_VL_ONEXEC flag,
+ length, or calling PR_SME_SET_VL with the PR_SME_SET_VL_ONEXEC flag,
does not constitute a change to the vector length for this purpose.
* Changing the vector length causes PSTATE.ZA and PSTATE.SM to be cleared.
Calling PR_SME_SET_VL with vl equal to the thread's current vector
- length, or calling PR_SME_SET_VL with the PR_SVE_SET_VL_ONEXEC flag,
+ length, or calling PR_SME_SET_VL with the PR_SME_SET_VL_ONEXEC flag,
does not constitute a change to the vector length for this purpose.
@@ -379,9 +379,8 @@ The regset data starts with struct user_za_header, containing:
/proc/sys/abi/sme_default_vector_length
Writing the text representation of an integer to this file sets the system
- default vector length to the specified value, unless the value is greater
- than the maximum vector length supported by the system in which case the
- default vector length is set to that maximum.
+ default vector length to the specified value rounded to a supported value
+ using the same rules as for setting vector length via PR_SME_SET_VL.
The result can be determined by reopening the file and reading its
contents.
diff --git a/Documentation/arch/arm64/sve.rst b/Documentation/arch/arm64/sve.rst
index 0d9a426e9f858..8d8837fc39ec7 100644
--- a/Documentation/arch/arm64/sve.rst
+++ b/Documentation/arch/arm64/sve.rst
@@ -117,11 +117,6 @@ the SVE instruction set architecture.
* The SVE registers are not used to pass arguments to or receive results from
any syscall.
-* In practice the affected registers/bits will be preserved or will be replaced
- with zeros on return from a syscall, but userspace should not make
- assumptions about this. The kernel behaviour may vary on a case-by-case
- basis.
-
* All other SVE state of a thread, including the currently configured vector
length, the state of the PR_SVE_VL_INHERIT flag, and the deferred vector
length (if any), is preserved across all syscalls, subject to the specific
@@ -428,9 +423,8 @@ The regset data starts with struct user_sve_header, containing:
/proc/sys/abi/sve_default_vector_length
Writing the text representation of an integer to this file sets the system
- default vector length to the specified value, unless the value is greater
- than the maximum vector length supported by the system in which case the
- default vector length is set to that maximum.
+ default vector length to the specified value rounded to a supported value
+ using the same rules as for setting vector length via PR_SVE_SET_VL.
The result can be determined by reopening the file and reading its
contents.