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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perf(mpmm): greatly simplify MPMM enablement

MPMM is a core-specific microarchitectural feature. It has been present
in every Arm core since the Cortex-A510 and has been implemented in
exactly the s

perf(mpmm): greatly simplify MPMM enablement

MPMM is a core-specific microarchitectural feature. It has been present
in every Arm core since the Cortex-A510 and has been implemented in
exactly the same way. Despite that, it is enabled more like an
architectural feature with a top level enable flag. This utilised the
identical implementation.

This duality has left MPMM in an awkward place, where its enablement
should be generic, like an architectural feature, but since it is not,
it should also be core-specific if it ever changes. One choice to do
this has been through the device tree.

This has worked just fine so far, however, recent implementations expose
a weakness in that this is rather slow - the device tree has to be read,
there's a long call stack of functions with many branches, and system
registers are read. In the hot path of PSCI CPU powerdown, this has a
significant and measurable impact. Besides it being a rather large
amount of code that is difficult to understand.

Since MPMM is a microarchitectural feature, its correct placement is in
the reset function. The essence of the current enablement is to write
CPUPPMCR_EL3.MPMM_EN if CPUPPMCR_EL3.MPMMPINCTL == 0. Replacing the C
enablement with an assembly macro in each CPU's reset function achieves
the same effect with just a single close branch and a grand total of 6
instructions (versus the old 2 branches and 32 instructions).

Having done this, the device tree entry becomes redundant. Should a core
that doesn't support MPMM arise, this can cleanly be handled in the
reset function. As such, the whole ENABLE_MPMM_FCONF and platform hooks
mechanisms become obsolete and are removed.

Change-Id: I1d0475b21a1625bb3519f513ba109284f973ffdf
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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perf(cpus): inline the reset function

Similar to the cpu_rev_var and cpu_ger_rev_var functions, inline the
call_reset_handler handler. This way we skip the costly branch at no
extra cost as this is

perf(cpus): inline the reset function

Similar to the cpu_rev_var and cpu_ger_rev_var functions, inline the
call_reset_handler handler. This way we skip the costly branch at no
extra cost as this is the only place where this is called.

While we're at it, drop the options for CPU_NO_RESET_FUNC. The only cpus
that need that are virtual cpus which can spare the tiny bit of
performance lost. The rest are real cores which can save on the check
for zero.

Now is a good time to put the assert for a missing cpu in the
get_cpu_ops_ptr function so that it's a bit better encapsulated.

Change-Id: Ia7c3dcd13b75e5d7c8bafad4698994ea65f42406
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 changes I765a7fa0,Ic33f0b6d,I8d1a88c7,I381f96be,I698fa849, ... into integration

* changes:
fix(cpus): clear CPUPWRCTLR_EL1.CORE_PWRDN_EN_BIT on reset
chore(docs): drop the "wfi" from `pwr_

Merge changes I765a7fa0,Ic33f0b6d,I8d1a88c7,I381f96be,I698fa849, ... into integration

* changes:
fix(cpus): clear CPUPWRCTLR_EL1.CORE_PWRDN_EN_BIT on reset
chore(docs): drop the "wfi" from `pwr_domain_pwr_down_wfi`
chore(psci): drop skip_wfi variable
feat(arm): convert arm platforms to expect a wakeup
fix(cpus): avoid SME related loss of context on powerdown
feat(psci): allow cores to wake up from powerdown
refactor: panic after calling psci_power_down_wfi()
refactor(cpus): undo errata mitigations
feat(cpus): add sysreg_bit_toggle

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fix: add support for 128-bit sysregs to EL3 crash handler

The following changes have been made:
* Add new sysreg definitions and ASM macro is_feat_sysreg128_present_asm
* Add registers TTBR0_EL2 and

fix: add support for 128-bit sysregs to EL3 crash handler

The following changes have been made:
* Add new sysreg definitions and ASM macro is_feat_sysreg128_present_asm
* Add registers TTBR0_EL2 and VTTBR_EL2 to EL3 crash handler output
* Use MRRS instead of MRS for registers TTBR0_EL1, TTBR0_EL2, TTBR1_EL1,
VTTBR_EL2 and PAR_EL1

Change-Id: I0e20b2c35251f3afba2df794c1f8bc0c46c197ff
Signed-off-by: Igor Podgainõi <igor.podgainoi@arm.com>

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fix(cpus): avoid SME related loss of context on powerdown

Travis' and Gelas' TRMs tell us to disable SME (set PSTATE.{ZA, SM} to
0) when we're attempting to power down. What they don't tell us is th

fix(cpus): avoid SME related loss of context on powerdown

Travis' and Gelas' TRMs tell us to disable SME (set PSTATE.{ZA, SM} to
0) when we're attempting to power down. What they don't tell us is that
if this isn't done, the powerdown request will be rejected. On the
CPU_OFF path that's not a problem - we can force SVCR to 0 and be
certain the core will power off.

On the suspend to powerdown path, however, we cannot do this. The TRM
also tells us that the sequence could also be aborted on eg. GIC
interrupts. If this were to happen when we have overwritten SVCR to 0,
upon a return to the caller they would experience a loss of context. We
know that at least Linux may call into PSCI with SVCR != 0. One option
is to save the entire SME context which would be quite expensive just to
work around. Another option is to downgrade the request to a normal
suspend when SME was left on. This option is better as this is expected
to happen rarely enough to ignore the wasted power and we don't want to
burden the generic (correct) path with needless context management.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Change-Id: I698fa8490ebf51461f6aa8bba84f9827c5c46ad4

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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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refactor(cm): change owning security state when a feature is disabled

SPE and TRBE don't have an outright EL3 disable, there are only
constraints on what's allowed. Since we only enable them for NS

refactor(cm): change owning security state when a feature is disabled

SPE and TRBE don't have an outright EL3 disable, there are only
constraints on what's allowed. Since we only enable them for NS at the
moment, we want NS to own the buffers even when the feature should be
"disabled" for a world. This means that when we're running in NS
everything is as normal but when running in S/RL then tracing is
prohibited (since the buffers are owned by NS). This allows us to fiddle
with context a bit more without having to context switch registers.

Change-Id: Ie1dc7c00e4cf9bcc746f02ae43633acca32d3758
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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feat(aarch64): add DBGPRCR_EL1 register accessors

This is a small change adding accessor functions for the Debug Power
Control register (DBGPRCR_EL1) to the common architectural helpers.

Change-Id:

feat(aarch64): add DBGPRCR_EL1 register accessors

This is a small change adding accessor functions for the Debug Power
Control register (DBGPRCR_EL1) to the common architectural helpers.

Change-Id: I72261fbf0395d900347b46af320093ed946aa73d
Signed-off-by: Chris Kay <chris.kay@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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Merge "build(bl31): support separated memory for RW DATA" into integration

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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build(bl31): support separated memory for RW DATA

Update linker file and init codes to allow using separated
memory region for RW DATA. Init codes will copy the RW DATA
from the image to the linked

build(bl31): support separated memory for RW DATA

Update linker file and init codes to allow using separated
memory region for RW DATA. Init codes will copy the RW DATA
from the image to the linked address.

On some NXP platforms, after the BL31 image has been verified,
the bl31 image space will be locked/protected as RO only, so
need to move the RW DATA and NOBITS out of the bl31 image.

Signed-off-by: Ye Li <ye.li@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Change-Id: I361d9a715890961bf30790a3325f8085a40c0c39

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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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feat(context-mgmt): introduce EL3/root context

* This patch adds root context procedure to restore/configure
the registers, which are of importance during EL3 execution.

* EL3/Root context is a s

feat(context-mgmt): introduce EL3/root context

* This patch adds root context procedure to restore/configure
the registers, which are of importance during EL3 execution.

* EL3/Root context is a simple restore operation that overwrites
the following bits: (MDCR_EL3.SDD, SCR_EL3.{EA, SIF}, PMCR_EL0.DP
PSTATE.DIT) while the execution is in EL3.

* It ensures EL3 world maintains its own settings distinct
from other worlds (NS/Realm/SWd). With this in place, the EL3
system register settings is no longer influenced by settings of
incoming worlds. This allows the EL3/Root world to access features
for its own execution at EL3 (eg: Pauth).

* It should be invoked at cold and warm boot entry paths and also
at all the possible exception handlers routing to EL3 at runtime.
Cold and warm boot paths are handled by including setup_el3_context
function in "el3_entrypoint_common" macro, which gets invoked in
both the entry paths.

* At runtime, el3_context is setup at the stage, while we get prepared
to enter into EL3 via "prepare_el3_entry" routine.

Change-Id: I5c090978c54a53bc1c119d1bc5fa77cd8813cdc2
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>

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feat(sctlr2): add support for FEAT_SCTLR2

Arm v8.9 introduces FEAT_SCTLR2, adding SCTLR2_ELx registers.
Support this, context switching the registers and disabling
traps so lower ELs can access the

feat(sctlr2): add support for FEAT_SCTLR2

Arm v8.9 introduces FEAT_SCTLR2, adding SCTLR2_ELx registers.
Support this, context switching the registers and disabling
traps so lower ELs can access the new registers.

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: I0c4cba86917b6b065a7e8dd6af7daf64ee18dcda
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>

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