diff options
Diffstat (limited to 'Documentation/arch/arm64')
| -rw-r--r-- | Documentation/arch/arm64/cpu-feature-registers.rst | 13 | ||||
| -rw-r--r-- | Documentation/arch/arm64/silicon-errata.rst | 2 | ||||
| -rw-r--r-- | Documentation/arch/arm64/sme.rst | 8 |
3 files changed, 13 insertions, 10 deletions
diff --git a/Documentation/arch/arm64/cpu-feature-registers.rst b/Documentation/arch/arm64/cpu-feature-registers.rst index 253e9743de2f..add66afc7b03 100644 --- a/Documentation/arch/arm64/cpu-feature-registers.rst +++ b/Documentation/arch/arm64/cpu-feature-registers.rst @@ -72,14 +72,15 @@ there are some issues with their usage. process could be migrated to another CPU by the time it uses the register value, unless the CPU affinity is set. Hence, there is no guarantee that the value reflects the processor that it is - currently executing on. The REVIDR is not exposed due to this - constraint, as REVIDR makes sense only in conjunction with the - MIDR. Alternately, MIDR_EL1 and REVIDR_EL1 are exposed via sysfs - at:: + currently executing on. REVIDR and AIDR are not exposed due to this + constraint, as these registers only make sense in conjunction with + the MIDR. Alternately, MIDR_EL1, REVIDR_EL1, and AIDR_EL1 are exposed + via sysfs at:: /sys/devices/system/cpu/cpu$ID/regs/identification/ - \- midr - \- revidr + \- midr_el1 + \- revidr_el1 + \- aidr_el1 3. Implementation -------------------- diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst index f968c13b46a7..b18ef4064bc0 100644 --- a/Documentation/arch/arm64/silicon-errata.rst +++ b/Documentation/arch/arm64/silicon-errata.rst @@ -57,6 +57,8 @@ stable kernels. +----------------+-----------------+-----------------+-----------------------------+ | Ampere | AmpereOne AC04 | AC04_CPU_10 | AMPERE_ERRATUM_AC03_CPU_38 | +----------------+-----------------+-----------------+-----------------------------+ +| Ampere | AmpereOne AC04 | AC04_CPU_23 | AMPERE_ERRATUM_AC04_CPU_23 | ++----------------+-----------------+-----------------+-----------------------------+ +----------------+-----------------+-----------------+-----------------------------+ | ARM | Cortex-A510 | #2457168 | ARM64_ERRATUM_2457168 | +----------------+-----------------+-----------------+-----------------------------+ diff --git a/Documentation/arch/arm64/sme.rst b/Documentation/arch/arm64/sme.rst index b2fa01f85cb5..4cb38330e704 100644 --- a/Documentation/arch/arm64/sme.rst +++ b/Documentation/arch/arm64/sme.rst @@ -69,8 +69,8 @@ model features for SME is included in Appendix A. vectors from 0 to VL/8-1 stored in the same endianness invariant format as is used for SVE vectors. -* On thread creation TPIDR2_EL0 is preserved unless CLONE_SETTLS is specified, - in which case it is set to 0. +* On thread creation PSTATE.ZA and TPIDR2_EL0 are preserved unless CLONE_VM + is specified, in which case PSTATE.ZA is set to 0 and TPIDR2_EL0 is set to 0. 2. Vector lengths ------------------ @@ -115,7 +115,7 @@ be zeroed. 5. Signal handling ------------------- -* Signal handlers are invoked with streaming mode and ZA disabled. +* Signal handlers are invoked with PSTATE.SM=0, PSTATE.ZA=0, and TPIDR2_EL0=0. * A new signal frame record TPIDR2_MAGIC is added formatted as a struct tpidr2_context to allow access to TPIDR2_EL0 from signal handlers. @@ -241,7 +241,7 @@ prctl(PR_SME_SET_VL, unsigned long arg) 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. + * Changing the vector length causes PSTATE.ZA 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_SME_SET_VL_ONEXEC flag, does not constitute a change to the vector length for this purpose. |