The AMU counter AMEVCNTR01 (constant counter) should increment at the same
rate as the system counter. On affected Cortex-A510 cores, AMEVCNTR01
increments incorrectly giving a significantly higher output value. This
results in inaccurate task scheduler utilization tracking and incorrect
feedback on CPU frequency.

Work around this problem by returning 0 when reading the affected counter
in key locations that results in disabling all users of this counter from
using it either for frequency invariance or as FFH reference counter. This
effect is the same to firmware disabling affected counters.

Details on how the two features are affected by this erratum:

 - AMU counters will not be used for frequency invariance for affected
   CPUs and CPUs in the same cpufreq policy. AMUs can still be used for
   frequency invariance for unaffected CPUs in the system. Although
   unlikely, if no alternative method can be found to support frequency
   invariance for affected CPUs (cpufreq based or solution based on
   platform counters) frequency invariance will be disabled. Please check
   the chapter on frequency invariance at
   Documentation/scheduler/sched-capacity.rst for details of its effect.

 - Given that FFH can be used to fetch either the core or constant counter
   values, restrictions are lifted regarding any of these counters
   returning a valid (!0) value. Therefore FFH is considered supported
   if there is a least one CPU that support AMUs, independent of any
   counters being disabled or affected by this erratum. Clarifying
   comments are now added to the cpc_ffh_supported(), cpu_read_constcnt()
   and cpu_read_corecnt() functions.

The above is achieved through adding a new erratum: ARM64_ERRATUM_2457168.

Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220819103050.24211-1-ionela.voinescu@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

* for-next/cpufeature:
  arm64/hwcap: Support FEAT_EBF16
  arm64/cpufeature: Store elf_hwcaps as a bitmap rather than unsigned long
  arm64/hwcap: Document allocation of upper bits of AT_HWCAP
  arm64: trap implementation defined functionality in userspace

* for-next/sysregs: (28 commits)
  arm64/sysreg: Convert ID_AA64ZFR0_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64SMFR0_EL1 to automatic generation
  arm64/sysreg: Convert LORID_EL1 to automatic generation
  arm64/sysreg: Convert LORC_EL1 to automatic generation
  arm64/sysreg: Convert LORN_EL1 to automatic generation
  arm64/sysreg: Convert LOREA_EL1 to automatic generation
  arm64/sysreg: Convert LORSA_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64ISAR2_EL1 to automatic generation
  arm64/sysreg: Convert ID_AA64ISAR1_EL1 to automatic generation
  arm64/sysreg: Convert GMID to automatic generation
  arm64/sysreg: Convert DCZID_EL0 to automatic generation
  arm64/sysreg: Convert CTR_EL0 to automatic generation
  arm64/sysreg: Add _EL1 into ID_AA64ISAR2_EL1 definition names
  arm64/sysreg: Add _EL1 into ID_AA64ISAR1_EL1 definition names
  arm64/sysreg: Remove defines for RPRES enumeration
  arm64/sysreg: Standardise naming for ID_AA64ZFR0_EL1 fields
  arm64/sysreg: Standardise naming for ID_AA64SMFR0_EL1 enums
  arm64/sysreg: Standardise naming for WFxT defines
  arm64/sysreg: Make BHB clear feature defines match the architecture
  arm64/sysreg: Align pointer auth enumeration defines with architecture
  ...

Cortex-A57 and Cortex-A72 have an erratum where an interrupt that
occurs between a pair of AES instructions in aarch32 mode may corrupt
the ELR. The task will subsequently produce the wrong AES result.

The AES instructions are part of the cryptographic extensions, which are
optional. User-space software will detect the support for these
instructions from the hwcaps. If the platform doesn't support these
instructions a software implementation should be used.

Remove the hwcap bits on affected parts to indicate user-space should
not use the AES instructions.

Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220714161523.279570-3-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

Convert ID_AA64ZFR0_EL1 to automatic register generation as per DDI0487H.a,
no functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-29-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Convert ID_AA64SMFR0_EL1 to automatic register generation as per DDI0487H.a,
no functional change.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-28-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Convert LORID_EL1 to automatic register generation as per DDI0487H.a, no
functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-27-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Convert LORC_EL1 to automatic register generation as per DDI0487H.a, no
functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-26-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Convert LORN_EL1 to automatic register generation as per DDI0487H.a, no
functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-25-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Convert LOREA_EL1 to automatic register generation as per DDI0487H.a, no
functional changes.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220704170302.2609529-24-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>