perf(cm): drop ZCR_EL3 saving and some ISBs and replace them with root context

SVE and SME aren't enabled symmetrically for all worlds, but EL3 needs
to context switch them nonetheless. Previously,

perf(cm): drop ZCR_EL3 saving and some ISBs and replace them with root context

SVE and SME aren't enabled symmetrically for all worlds, but EL3 needs
to context switch them nonetheless. Previously, this had to happen by
writing the enable bits just before reading/writing the relevant
context. But since the introduction of root context, this need not be
the case. We can have these enables always be present for EL3 and save
on some work (and ISBs!) on every context switch.

We can also hoist ZCR_EL3 to a never changing register, as we set its
value to be identical for every world, which happens to be the one we
want for EL3 too.

Change-Id: I3d950e72049a298008205ba32f230d5a5c02f8b0
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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perf(amu): greatly simplify AMU context management

The current code is incredibly resilient to updates to the spec and
has worked quite well so far. However, recent implementations expose a
weakness

perf(amu): greatly simplify AMU context management

The current code is incredibly resilient to updates to the spec and
has worked quite well so far. However, recent implementations expose a
weakness in that this is rather slow. A large part of it is written in
assembly, making it opaque to the compiler for optimisations. The
future proofness requires reading registers that are effectively
`volatile`, making it even harder for the compiler, as well as adding
lots of implicit barriers, making it hard for the microarchitecutre to
optimise as well.

We can make a few assumptions, checked by a few well placed asserts, and
remove a lot of this burden. For a start, at the moment there are 4
group 0 counters with static assignments. Contexting them is a trivial
affair that doesn't need a loop. Similarly, there can only be up to 16
group 1 counters. Contexting them is a bit harder, but we can do with a
single branch with a falling through switch. If/when both of these
change, we have a pair of asserts and the feature detection mechanism to
guard us against pretending that we support something we don't.

We can drop contexting of the offset registers. They are fully
accessible by EL2 and as such are its responsibility to preserve on
powerdown.

Another small thing we can do, is pass the core_pos into the hook.
The caller already knows which core we're running on, we don't need to
call this non-trivial function again.

Finally, knowing this, we don't really need the auxiliary AMUs to be
described by the device tree. Linux doesn't care at the moment, and any
information we need for EL3 can be neatly placed in a simple array.

All of this, combined with lifting the actual saving out of assembly,
reduces the instructions to save the context from 180 to 40, including a
lot fewer branches. The code is also much shorter and easier to read.

Also propagate to aarch32 so that the two don't diverge too much.

Change-Id: Ib62e6e9ba5be7fb9fb8965c8eee148d5598a5361
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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Merge changes from topic "bk/errata_speed" into integration

* changes:
refactor(cpus): declare runtime errata correctly
perf(cpus): make reset errata do fewer branches
perf(cpus): inline the i

Merge changes from topic "bk/errata_speed" into integration

* changes:
refactor(cpus): declare runtime errata correctly
perf(cpus): make reset errata do fewer branches
perf(cpus): inline the init_cpu_data_ptr function
perf(cpus): inline the reset function
perf(cpus): inline the cpu_get_rev_var call
perf(cpus): inline cpu_rev_var checks
refactor(cpus): register DSU errata with the errata framework's wrappers
refactor(cpus): convert checker functions to standard helpers
refactor(cpus): convert the Cortex-A65 to use the errata framework
fix(cpus): declare reset errata correctly

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perf(cpus): inline the init_cpu_data_ptr function

Similar to the reset function inline, inline this too to not do a costly
branch with no extra cost.

Change-Id: I54cc399e570e9d0f373ae13c7224d32dbdf

perf(cpus): inline the init_cpu_data_ptr function

Similar to the reset function inline, inline this too to not do a costly
branch with no extra cost.

Change-Id: I54cc399e570e9d0f373ae13c7224d32dbdfae1e5
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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fix(rmm): add support for BRBCR_EL2 register for feat_brbe

Currently BRBE is being disabled for Realm world in EL3 by
switching the SBRBE bit in mdcr_el3 register to 0b00.
The patch removes the swit

fix(rmm): add support for BRBCR_EL2 register for feat_brbe

Currently BRBE is being disabled for Realm world in EL3 by
switching the SBRBE bit in mdcr_el3 register to 0b00.
The patch removes the switching of SBRBE bits, and adds
context switch of BRBCR_EL2 register.

Change-Id: I66ca13edefc37e40fa265fd438b0b66f7d09b4bb
Signed-off-by: Sona Mathew <sonarebecca.mathew@arm.com>

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Merge "fix(simd): fix base register in fpregs_context_*" into integration

refactor(cpufeat): add FGT2 and Debugv8p9 to realm state

Enable FEAT_FGT2 and FEAT_Debugv8p9 in Realm state as well.

Change-Id: Ib9cdde3af328ffdd8718b1ba404265757f2e542b
Signed-off-by: Sona Mathew

refactor(cpufeat): add FGT2 and Debugv8p9 to realm state

Enable FEAT_FGT2 and FEAT_Debugv8p9 in Realm state as well.

Change-Id: Ib9cdde3af328ffdd8718b1ba404265757f2e542b
Signed-off-by: Sona Mathew <sonarebecca.mathew@arm.com>

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fix(cpus): workaround for accessing ICH_VMCR_EL2

When ICH_VMCR_EL2.VBPR1 is written in Secure state (SCR_EL3.NS==0)
and then subsequently read in Non-secure state (SCR_EL3.NS==1), a
wrong value migh

fix(cpus): workaround for accessing ICH_VMCR_EL2

When ICH_VMCR_EL2.VBPR1 is written in Secure state (SCR_EL3.NS==0)
and then subsequently read in Non-secure state (SCR_EL3.NS==1), a
wrong value might be returned. The same issue exists in the opposite way.

Adding workaround in EL3 software that performs context save/restore
on a change of Security state to use a value of SCR_EL3.NS when
accessing ICH_VMCR_EL2 that reflects the Security state that owns the
data being saved or restored. For example, EL3 software should set
SCR_EL3.NS to 1 when saving or restoring the value ICH_VMCR_EL2 for
Non-secure(or Realm) state. EL3 software should clear
SCR_EL3.NS to 0 when saving or restoring the value ICH_VMCR_EL2 for
Secure state.

SDEN documentation:
https://developer.arm.com/documentation/SDEN-1775101/latest/

Change-Id: I9f0403601c6346276e925f02eab55908b009d957
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>

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fix(simd): fix base register in fpregs_context_*

The fpregs_state_* macros require the base register
to point to the start of the simd_regs_t structure.
The fpregs_context_* functions were passing t

fix(simd): fix base register in fpregs_context_*

The fpregs_state_* macros require the base register
to point to the start of the simd_regs_t structure.
The fpregs_context_* functions were passing the
address incorrectly shifted by 512 bytes.

Signed-off-by: Andrei Homescu <ahomescu@google.com>
Change-Id: I757a26f8910c2ab648116e001e06baa3deb2eec4

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Merge "feat(pmuv3): setup per world MDCR_EL3" into integration

feat(pmuv3): setup per world MDCR_EL3

MDCR_EL3 register will context switch across all worlds. Thus the pmuv3
init has to be part of context management initialization.

Change-Id: I10ef7a3071c0fc5c1

feat(pmuv3): setup per world MDCR_EL3

MDCR_EL3 register will context switch across all worlds. Thus the pmuv3
init has to be part of context management initialization.

Change-Id: I10ef7a3071c0fc5c11a93d3c9c2a95ec8c6493bf
Signed-off-by: Mateusz Sulimowicz <matsul@google.com>

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feat(mops): enable FEAT_MOPS in EL3 when INIT_UNUSED_NS_EL2=1

FEAT_MOPS, mandatory from Arm v8.8, is typically managed in EL2.
However, in configurations where NS_EL2 is not enabled,
EL3 must set th

feat(mops): enable FEAT_MOPS in EL3 when INIT_UNUSED_NS_EL2=1

FEAT_MOPS, mandatory from Arm v8.8, is typically managed in EL2.
However, in configurations where NS_EL2 is not enabled,
EL3 must set the HCRX_EL2.MSCEn bit to 1 to enable the feature.

This patch ensures FEAT_MOPS is enabled by setting HCRX_EL2.MSCEn to 1.

Change-Id: Ic4960e0cc14a44279156b79ded50de475b3b21c5
Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>

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refactor(cm): clean up per-world context

In preparation for SMCCC_ARCH_FEATURE_AVAILABILITY, it is useful for
context to be directly related to the underlying system. Currently,
certain bits like SC

refactor(cm): clean up per-world context

In preparation for SMCCC_ARCH_FEATURE_AVAILABILITY, it is useful for
context to be directly related to the underlying system. Currently,
certain bits like SCR_EL3.APK are always set with the understanding that
they will only take effect if the feature is present.

However, that is problematic for SMCCC_ARCH_FEATURE_AVAILABILITY (an
SMCCC call to report which features firmware enables), as simply reading
the enable bit may contradict the ID register, like the APK bit above
for a system with no Pauth present.

This patch is to clean up these cases. Add a check for PAuth's presence
so that the APK bit remains unset if not present. Also move SPE and TRBE
enablement to only the NS context. They already only enable the features
for NS only and disable them for Secure and Realm worlds. This change
only makes these worlds' context read 0 for easy bitmasking.

There's only a single snag on SPE and TRBE. Currently, their fields have
the same values and any world asymmetry is handled by hardware. Since we
don't want to do that, the buffers' ownership will change if we just set
the fields to 0 for non-NS worlds. Doing that, however, exposes Secure
state to a potential denial of service attack - a malicious NS can
enable profiling and call an SMC. Then, the owning security state will
change and since no SPE/TRBE registers are contexted, Secure state will
start generating records. Always have NS world own the buffers to
prevent this.

Finally, get rid of manage_extensions_common() as it's just a level of
indirection to enable a single feature.

Change-Id: I487bd4c70ac3e2105583917a0e5499e0ee248ed9
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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Merge changes from topic "bk/smccc_feature" into integration

* changes:
fix(trbe): add a tsb before context switching
fix(spe): add a psb before updating context and remove context saving

fix(cm): fix context management SYSREG128 write macros

This patch fixes a bug which was introduced in commit
3065513 related to improper saving of EL1 context in the
context management library code

fix(cm): fix context management SYSREG128 write macros

This patch fixes a bug which was introduced in commit
3065513 related to improper saving of EL1 context in the
context management library code when using 128-bit
system registers.

Bug explanation:
The function el1_sysregs_context_save still used the normal
macros that read all the system registers related to the EL1
context, which then involved casting them to uint64_t and
eventually writing them to a memory structure. This means that
the context management library was saving EL1-related SYSREG128
registers with the upper 64 bits zeroed out.

Alternative macros had previously been introduced for the EL2
context in the aforementioned commit, but not for EL1.

Some refactoring has also been done as part of this patch:
- Re-added "common" back to write_el2_ctx_common_sysreg128
- Added dummy SYSREG128 macros for cases when some features
are disabled
- Removed some newlines

Change-Id: I15aa2190794ac099a493e5f430220b1c81e1b558
Signed-off-by: Igor Podgainõi <igor.podgainoi@arm.com>

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fix(trbe): add a tsb before context switching

Just like for SPE, we need to synchronize TRBE samples before we change
the context to ensure everything goes where it was intended to. If that
is not d

fix(trbe): add a tsb before context switching

Just like for SPE, we need to synchronize TRBE samples before we change
the context to ensure everything goes where it was intended to. If that
is not done, the in-flight entries might use any piece of now incorrect
context as there are no implicit ordering requirements.

Prior to root context, the buffer drain hooks would have done that. But
now that must happen much earlier. So add a tsb to prepare_el3_entry as
well.

Annoyingly, the barrier can be reordered relative to other instructions
by default (rule RCKVWP). So add an isb after the psb/tsb to assure that
they are ordered, at least as far as context is concerned.

Then, drop the buffer draining hooks. Everything they need to do is
already done by now. There's a notable difference in that there are no
dsb-s now. Since EL3 does not access the buffers or the feature
specific context, we don't need to wait for them to finish.

Finally, drop a stray isb in the context saving macro. It is now
absorbed into root context, but was missed.

Change-Id: I30797a40ac7f91d0bb71ad271a1597e85092ccd5
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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fix(spe): add a psb before updating context and remove context saving

In the chapter about FEAT_SPE (D16.4 specifically) it is stated that
"Sampling is always disabled at EL3". That means that disab

fix(spe): add a psb before updating context and remove context saving

In the chapter about FEAT_SPE (D16.4 specifically) it is stated that
"Sampling is always disabled at EL3". That means that disabling sampling
(writing PMBLIMITR_EL1.E to 0) is redundant and can be removed. The only
reason we save/restore SPE context is because of that disable, so those
can be removed too.

There's the issue of draining the profiling buffer though. No new
samples will have been generated since entering EL3. However, old
samples might still be in-flight. Unless synchronised by a psb csync,
those might be affected by our extensive context mutation. Adding a psb
in prepare_el3_entry should cater for that. Note that prior to the
introduction of root context this was not a problem as context remained
unchanged and the hooks took care of the rest.

Then, the only time we care about the buffer actually making it to
memory is when we exit coherency. On HW_ASSISTED_COHERENCY systems we
don't have to do anything, it should be handled for us. Systems without
it need a dsb to wait for them to complete. There should be one already
in each cpu's powerdown hook which should work.

While on the topic of barriers, the esb barrier is no longer used.
Remove it.

Change-Id: I9736fc7d109702c63e7d403dc9e2a4272828afb2
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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feat(fpmr): disable FPMR trap

This patch enables support of FEAT_FPMR by enabling access
to FPMR register. It achieves it by setting the EnFPM bit of
SCR_EL3. This feature is currently enabled for N

feat(fpmr): disable FPMR trap

This patch enables support of FEAT_FPMR by enabling access
to FPMR register. It achieves it by setting the EnFPM bit of
SCR_EL3. This feature is currently enabled for NS world only.

Reference:
https://developer.arm.com/documentation/109697/2024_09/
Feature-descriptions/The-Armv9-5-architecture-extension?lang=en

Change-Id: I580c409b9b22f8ead0737502280fb9093a3d5dd2
Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>

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feat(cpufeat): add ENABLE_FEAT_LS64_ACCDATA

Armv8.6 introduced the FEAT_LS64 extension, which provides a 64 *byte*
store instruction. A related instruction is ST64BV0, which will replace
the lowest

feat(cpufeat): add ENABLE_FEAT_LS64_ACCDATA

Armv8.6 introduced the FEAT_LS64 extension, which provides a 64 *byte*
store instruction. A related instruction is ST64BV0, which will replace
the lowest 32 bits of the data with a value taken from the ACCDATA_EL1
system register (so that EL0 cannot alter them).
Using that ST64BV0 instruction and accessing the ACCDATA_EL1 system
register is guarded by two SCR_EL3 bits, which we should set to avoid a
trap into EL3, when lower ELs use one of those.

Add the required bits and pieces to make this feature usable:
- Add the ENABLE_FEAT_LS64_ACCDATA build option (defaulting to 0).
- Add the CPUID and SCR_EL3 bit definitions associated with FEAT_LS64.
- Add a feature check to check for the existing four variants of the
LS64 feature and detect future extensions.
- Add code to save and restore the ACCDATA_EL1 register on
secure/non-secure context switches.
- Enable the feature with runtime detection for FVP and Arm FPGA.

Please note that the *basic* FEAT_LS64 feature does not feature any trap
bits, it's only the addition of the ACCDATA_EL1 system register that
adds these traps and the SCR_EL3 bits.

Change-Id: Ie3e2ca2d9c4fbbd45c0cc6089accbb825579138a
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

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Merge "feat(feat_sctlr2): enable FEAT_SCTLR2 for Realm world" into integration

feat(feat_sctlr2): enable FEAT_SCTLR2 for Realm world

Change-Id: I62e769ae796bbeb41741c2c421a5f129d875f5fb
Signed-off-by: Javier Almansa Sobrino <javier.almansasobrino@arm.com>

feat(d128): add support for FEAT_D128

This patch disables trapping to EL3 when the FEAT_D128
specific registers are accessed by setting the SCR_EL3.D128En bit.

If FEAT_D128 is implemented, then FEA

feat(d128): add support for FEAT_D128

This patch disables trapping to EL3 when the FEAT_D128
specific registers are accessed by setting the SCR_EL3.D128En bit.

If FEAT_D128 is implemented, then FEAT_SYSREG128 is implemented.
With FEAT_SYSREG128 certain system registers are treated as 128-bit,
so we should be context saving and restoring 128-bits instead of 64-bit
when FEAT_D128 is enabled.

FEAT_SYSREG128 adds support for MRRS and MSRR instruction which
helps us to read write to 128-bit system register.
Refer to Arm Architecture Manual for further details.

Change the FVP platform to default to handling this as a dynamic option
so the right decision can be made by the code at runtime.

Change-Id: I1a53db5eac29e56c8fbdcd4961ede3abfcb2411a
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>

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Merge "fix(brbe): allow RME builds with BRBE" into integration

Merge "feat(context-mgmt): introduce EL3/root context" into integration

fix(brbe): allow RME builds with BRBE

It used to be the case that a FEAT_RME build could not be built with
FEAT_BRBE support. BRBE doesn't have a 3-world aware disable and
MDCR_EL3 was not context s

fix(brbe): allow RME builds with BRBE

It used to be the case that a FEAT_RME build could not be built with
FEAT_BRBE support. BRBE doesn't have a 3-world aware disable and
MDCR_EL3 was not context switched to allow for disabling in Realm world.

As of commit 123002f9171384d976d95935b7f566740d69cc68 MDCR_EL3 is
context switched. Since the flag for BRBE support is
ENABLE_BRBE_FOR_NS, move brbe_enable() to only happen for NS world. The
other worlds will see BRBE disabled and branch recording prohibited.
This allows for a build with both RME and BRBE.

Note that EL2 BRBE registers are not context switched. Further work is
needed if non-NS support is required.

Change-Id: I82f0f08399dcd080902477dc9636bc4541685f89
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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