The hwcap string arrays used for generating the contents of
/proc/cpuinfo are currently arrays of non-const pointers.
There's no need for these pointers to be mutable, so this patch makes
them const so that they can be moved to .rodata.
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
At the moment we run through the arm64_features capability list for
each CPU and set the capability if one of the CPU supports it. This
could be problematic in a heterogeneous system with differing capabilities.
Delay the CPU feature checks until all the enabled CPUs are up(i.e,
smp_cpus_done(), so that we can make better decisions based on the
overall system capability. Once we decide and advertise the capabilities
the alternatives can be applied. From this state, we cannot roll back
a feature to disabled based on the values from a new hotplugged CPU,
due to the runtime patching and other reasons. So, for all new CPUs,
we need to make sure that they have the established system capabilities.
Failing which, we bring the CPU down, preventing it from turning online.
Once the capabilities are decided, any new CPU booting up goes through
verification to ensure that it has all the enabled capabilities and also
invokes the respective enable() method on the CPU.
The CPU errata checks are not delayed and is still executed per-CPU
to detect the respective capabilities. If we ever come across a non-errata
capability that needs to be checked on each-CPU, we could introduce them via
a new capability table(or introduce a flag), which can be processed per CPU.
The next patch will make the feature checks use the system wide
safe value of a feature register.
NOTE: The enable() methods associated with the capability is scheduled
on all the CPUs (which is the only use case at the moment). If we need
a different type of 'enable()' which only needs to be run once on any CPU,
we should be able to handle that when needed.
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
[catalin.marinas@arm.com: static variable and coding style fixes]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch consolidates the CPU Sanity check to the new infrastructure.
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch adds an infrastructure to keep track of the CPU feature
registers on the system. For each register, the infrastructure keeps
track of the system wide safe value of the feature bits. Also, tracks
the which fields of a register should be matched strictly across all
the CPUs on the system for the SANITY check infrastructure.
The feature bits are classified into following 3 types depending on
the implication of the possible values. This information is used to
decide the safe value for a feature.
LOWER_SAFE - The smaller value is safer
HIGHER_SAFE - The bigger value is safer
EXACT - We can't decide between the two, so a predefined safe_value is used.
This infrastructure will be later used to make better decisions for:
- Kernel features (e.g, KVM, Debug)
- SANITY Check
- CPU capability
- ELF HWCAP
- Exposing CPU Feature register to userspace.
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
[catalin.marinas@arm.com: whitespace fix]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch moves the /proc/cpuinfo handling code:
arch/arm64/kernel/{setup.c to cpuinfo.c}
No functional changes
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Move the mixed endian support detection code to cpufeature.c
from cpuinfo.c. This also moves the update_cpu_features()
used by mixed endian detection code, which will get more
functionality.
Also moves the ID register field shifts to asm/sysreg.h,
where all the useful definitions will end up in later patches.
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Tested-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
As we detect more architectural features at runtime, it makes
sense to reuse the existing framework whilst avoiding to call
a feature an erratum...
This patch extract the core capability parsing, moves it into
a new file (cpufeature.c), and let the CPU errata detection code
use it.
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This patch keeps track of the mixed endian EL0 support across
the system and provides helper functions to export it. The status
is a boolean indicating whether all the CPUs on the system supports
mixed endian at EL0.
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch adds support for cacheinfo on ARM64.
On ARMv8, the cache hierarchy can be identified through Cache Level ID
(CLIDR) register while the cache geometry is provided by Cache Size ID
(CCSIDR) register.
Since the architecture doesn't provide any way of detecting the cpus
sharing particular cache, device tree is used for the same purpose.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
We don't currently check a number of registers exposed to AArch32 guests
(MVFR{0,1,2}_EL1 and ID_DFR0_EL1), despite the fact these describe
AArch32 feature support exposed to userspace and KVM guests similarly to
AArch64 registers which we do check. We do not expect these registers to
vary across a set of CPUs.
This patch adds said registers to the cpuinfo framework and sanity
checks. No sanity check failures have been observed on a current ARMv8
big.LITTLE platform (Juno).
Cc: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
While we currently expect self-hosted debug support to be identical
across CPUs, we don't currently sanity check this.
This patch adds logging of the ID_AA64DFR{0,1}_EL1 values and associated
sanity checking code.
It's not clear to me whether we need to check PMUVer, TraceVer, and
DebugVer, as we don't currently rely on these fields at all.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
A missing newline in the WARN_TAINT_ONCE string results in ugly and
somewhat difficult to read output in the case of a sanity check failure,
as the next print does not appear on a new line:
Unsupported CPU feature variation.Modules linked in:
This patch adds the missing newline, fixing the output formatting.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
It seems that Cortex-A53 r0p4 added support for AIFSR and ADFSR, and
ID_MMFR0.AuxReg has been updated accordingly to report this fact. As
Cortex-A53 could be paired with CPUs which do not implement these
registers (e.g. all current revisions of Cortex-A57), this may trigger a
sanity check failure at boot.
The AuxReg value describes the availability of the ACTLR, AIFSR, and
ADFSR registers, which are only of use to 32-bit guest OSs, and have
IMPLEMENTATION DEFINED contents. Given the nature of these registers it
is likely that KVM will need to trap accesses regardless of whether the
CPUs are heterogeneous.
This patch masks out the ID_MMFR0.AuxReg value from the sanity checks,
preventing spurious warnings at boot time.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
After each CPU has been started, we iterate through a list of
CPU features or bugs to detect CPUs which need (or could benefit
from) kernel code patches.
For each feature/bug there is a function which checks if that
particular CPU is affected. We will later provide some more generic
functions for common things like testing for certain MIDR ranges.
We do this for every CPU to cover big.LITTLE systems properly as
well.
If a certain feature/bug has been detected, the capability bit will
be set, so that later the call to apply_alternatives() will trigger
the actual code patching.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
VIPT caches are non-aliasing if the index is derived from address bits that
are always equal between VA and PA. Classifying these as aliasing results in
unnecessary flushing which may hurt performance.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This adds helper functions and #defines to <asm/cachetype.h> to read the
line size and the number of sets from the level 1 instruction cache.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This removes an unfortunately placed semi-colon resulting in all instruction
caches being classified as AIVIVT.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Due to a missing newline in the I-cache policy detection log output,
it's possible to get some ratehr unfortunate output at boot time:
CPU1: Booted secondary processor
Detected VIPT I-cache on CPU1CPU2: Booted secondary processor
Detected VIPT I-cache on CPU2CPU3: Booted secondary processor
Detected VIPT I-cache on CPU3CPU4: Booted secondary processor
Detected PIPT I-cache on CPU4CPU5: Booted secondary processor
Detected PIPT I-cache on CPU5Brought up 6 CPUs
SMP: Total of 6 processors activated.
This patch adds the missing newline to the format string, cleaning up
the output.
Fixes: 59ccc0d41b ("arm64: cachetype: report weakest cache policy")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Unexpected variation in certain system register values across CPUs is an
indicator of potential problems with a system. The kernel expects CPUs
to be mostly identical in terms of supported features, even in systems
with heterogeneous CPUs, with uniform instruction set support being
critical for the correct operation of userspace.
To help detect issues early where hardware violates the expectations of
the kernel, this patch adds simple runtime sanity checks on important ID
registers in the bring up path of each CPU.
Where CPUs are fundamentally mismatched, set TAINT_CPU_OUT_OF_SPEC.
Given that the kernel assumes CPUs are identical feature wise, let's not
pretend that we expect such configurations to work. Supporting such
configurations would require massive rework, and hopefully they will
never exist.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In big.LITTLE systems, the I-cache policy may differ across CPUs, and
thus we must always meet the most stringent maintenance requirements of
any I-cache in the system when performing maintenance to ensure
correctness. Unfortunately this requirement is not met as we always look
at the current CPU's cache type register to determine the maintenance
requirements.
This patch causes the I-cache policy of all CPUs to be taken into
account for icache_is_aliasing and icache_is_aivivt. If any I-cache in
the system is aliasing or AIVIVT, the respective function will return
true. At boot each CPU may set flags to identify that at least one
I-cache in the system is aliasing and/or AIVIVT.
The now unused and potentially misleading icache_policy function is
removed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Several kernel subsystems need to know details about CPU system register
values, sometimes for CPUs other than that they are executing on. Rather
than hard-coding system register accesses and cross-calls for these
cases, this patch adds logic to record various system register values at
boot-time. This may be used for feature reporting, firmware bug
detection, etc.
Separate hooks are added for the boot and hotplug paths to enable
one-time intialisation and cold/warm boot value mismatch detection in
later patches.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Dave Martin