feat(cpufeat): enable USE_SPINLOCK_CAS to FEAT_STATE_CHECKED

The FEAT_LSE enablement predates the FEAT_STATE framework and has never
been converted. Since the introduction of USE_SPINLOCK_CAS we've

feat(cpufeat): enable USE_SPINLOCK_CAS to FEAT_STATE_CHECKED

The FEAT_LSE enablement predates the FEAT_STATE framework and has never
been converted. Since the introduction of USE_SPINLOCK_CAS we've gained
lots of quality of life features that allow for better feature
enablement. This patch converts USE_SPINLOCK_CAS to tri-state and adds
it to FEATURE_DETECTION to align with all other features.

Instead of introducing the assembly checking for tri-state, this patch
translates all locking routines to C inline assembly and uses the
standard C helpers. The main benefit is that this gives greater
visibility to the compiler about what the functions are doing and lets
it optimise better. Namely, it is able to allocate registers itself and
inline the functions when LTO is enabled.

An unsuccessful attempt was made to use the instructions directly and
have even flow control in C. This, however, made code very complicated
and less efficient in the tight loops of the spinlock.

The last use of ARM_ARCH_AT_LEAST goes away with this change and so this
macro is removed. It has now been fully superseded by the FEAT_STATE
framework.

This change exposes a limitation - RME_GPT_BITLOCK_BLOCK requires
USE_SPINLOCK_CAS. This patch does not address this in any way but makes
the relationship explicit.

Change-Id: I580081549aceded2dca3e0f4564ee7510a7e56ae
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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feat(per-cpu): integrate per-cpu framework into BL31/BL32

Integrate per-cpu support into BL31/BL32 by extending the following
areas:

Zero-initialization: Treats per-cpu sections like .bss and clear

feat(per-cpu): integrate per-cpu framework into BL31/BL32

Integrate per-cpu support into BL31/BL32 by extending the following
areas:

Zero-initialization: Treats per-cpu sections like .bss and clears them
during early C runtime initialization. For platforms that enable
NUMA_AWARE_PER_CPU, invokes a platform hook to zero-initialize
node-specific per-cpu regions.

Cache maintenance: Extends the BL31 exit path to clean dcache lines
covering the per-cpu region, ensuring data written by the primary core
is visible to secondary cores.

tpidr_el3 setup: Initializes tpidr_el3 with the base address of the
current CPU’s per-cpu section. This allows per-cpu framework to
resolve local cpu accesses efficiently.

The percpu_data object is currently stored in tpidr_el3. Since the
per-cpu framework will use tpidr_el3 for this-cpu access, percpu_data
must be migrated to avoid conflict. This commit moves percpu_data to
the per-cpu framework.

Signed-off-by: Sammit Joshi <sammit.joshi@arm.com>
Signed-off-by: Rohit Mathew <rohit.mathew@arm.com>
Change-Id: Iff0c2e1f8c0ebd25c4bb0b09bfe15dd4fbe20561

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feat(dsu): enable PMU registers access at EL1

- Disable trapping of write accesses to DSU cluster PMU registers
at EL3 and EL2.
- Clear the SPME bit in CLUSTERPMMDCR_EL3 to prohibit PMU event
co

feat(dsu): enable PMU registers access at EL1

- Disable trapping of write accesses to DSU cluster PMU registers
at EL3 and EL2.
- Clear the SPME bit in CLUSTERPMMDCR_EL3 to prohibit PMU event
counting in the secure state.

Change-Id: If3eb6e997330ae86f45760e0e862c003861f3d66
Signed-off-by: Amr Mohamed <amr.mohamed@arm.com>

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refactor(cpufeat): prepare FEAT_PAuth for FEATURE_DETECTION

Convert the old style is_armv8_3_pauth_present() to the new style
is_feat_pauth_{present, supported}() helpers and hook FEATURE_DETECTION

refactor(cpufeat): prepare FEAT_PAuth for FEATURE_DETECTION

Convert the old style is_armv8_3_pauth_present() to the new style
is_feat_pauth_{present, supported}() helpers and hook FEATURE_DETECTION
into it. This is in preparation for converting FEAT_PAuth to FEAT_STATE.

Change-Id: Iec8c3477fafb2cdae67d39ae4da2cca76a67511a
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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feat(cpufeat): enable FEAT_BTI to FEAT_STATE_CHECKED

Introduce the is_feat_bti_{supported, present}() helpers and replace
checks for ENABLE_BTI with it. Also factor out the setting of
SCTLR_EL3.BT o

feat(cpufeat): enable FEAT_BTI to FEAT_STATE_CHECKED

Introduce the is_feat_bti_{supported, present}() helpers and replace
checks for ENABLE_BTI with it. Also factor out the setting of
SCTLR_EL3.BT out of the PAuth enablement and place it in the respective
entrypoints where we initialise SCTLR_EL3. This makes PAuth
self-contained and SCTLR_EL3 initialisation centralised.

Change-Id: I0c0657ff1e78a9652cd2cf1603478283dc01f17b
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>

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fix(cpufeat): include FEAT_MOPS declaration in aarch32 header

This patch adds the missing is_feat_mops_supported() declaration
in aarch32 header.

Signed-off-by: Arvind Ram Prakash <arvind.ramprakas

fix(cpufeat): include FEAT_MOPS declaration in aarch32 header

This patch adds the missing is_feat_mops_supported() declaration
in aarch32 header.

Signed-off-by: Arvind Ram Prakash <arvind.ramprakash@arm.com>
Change-Id: I875f65defe23912351f9ef18555a5b0a0e53717d

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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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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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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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refactor(cpufeat): feat detect helpers inlining

Force inlining feat detect helpers such that context save/restore
operations are flattened with sequences of ID regs read and conditional
instructions

refactor(cpufeat): feat detect helpers inlining

Force inlining feat detect helpers such that context save/restore
operations are flattened with sequences of ID regs read and conditional
instructions for system registers read/write. This is opposed to current
situation where with -Os optimization level, feat detect helpers get
called through non-inlined sequences of branch-link+ret.

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I2633442fb0e69e4a4ed13467e65846fb66d214f6

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