At the moment we only support FEAT_BRBE to be either unconditionally
compiled in, or to be not supported at all.
Add support for runtime detection (ENABLE_BRBE_FOR_NS=2), by splitting
is_feat_brbe_present() into an ID register reading function and a second
function to report the support status. That function considers both
build time settings and runtime information (if needed), and is used
before we access BRBE related registers.
The FVP platform decided to compile in support unconditionally (=1),
even though FEAT_BRBE is an ARMv9 feature, so is not available with the
FVP model's default command line.
Change that to the now supported dynamic option (=2), so the right
decision can be made by the code at runtime.
Change-Id: I5f2e2c9648300f65f0fa9a5f8e2f34e73529d053
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
At the moment we only support FEAT_TRBE to be either unconditionally
compiled in, or to be not supported at all.
Add support for runtime detection (ENABLE_TRBE_FOR_NS=2), by splitting
is_feat_trbe_present() into an ID register reading function and a second
function to report the support status. That function considers both
build time settings and runtime information (if needed), and is used
before we access TRBE related registers.
The FVP platform decided to compile in support unconditionally (=1),
even though FEAT_TRBE is an ARMv9 feature, so is not available with the
FVP model's default command line.
Change that to the now supported dynamic option (=2), so the right
decision can be made by the code at runtime.
Change-Id: Iee7f88ea930119049543a8a4a105389997e7692c
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
So far the check_feature() function compares the subfield of a CPU ID
register against 0, to learn if a feature is enabled or not.
This is problematic for checks that require a certain revision of a
feature, so we should check against a minimum version number instead.
On top of that we might need to add code to support newer versions of a
feature, so we should be alerted if new hardware introduces a higher
number.
Extend the check_feature() function to take two extra arguments: the
minimum version, and the greatest currently known number.
Then make sure that the CPU ID field is in this range.
Change-Id: I425b68535a2ba9eafd31854e74d142183b521cd5
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Use the generic check function in feat_detect.c, and split the feature
check into two functions, as done for FEAT_FGT before.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: I0a4f973427c10d5d15c414ff5e12b18b7e645fae
For the FGT context save/restore operation, we need to look at the AMUv1
feature, so migrate this one over to the new scheme.
This uses the generic check function in feat_detect.c, and splits the
feature check into two functions, as was done before for FEAT_FGT.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: I95ad797f15001b2c9d1800c9d4af33fba79e136f
Split the feature check for FEAT_FGT into two parts:
- A boolean function that just evaluates whether the feature is usable.
This takes build time flags into account, and only evaluates the CPU
feature ID registers when the flexible FEAT_STATE_CHECK method is
used.
- A "raw" function that returns the unfiltered CPU feature ID register.
Change the callers where needed, to give them the version they actually
want.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: I9a041132d280451f5d9f653a62904f603b2a916d
To implement proper runtime checking of features, and to be able to
extend feat_detect.c to catch other cases, rework the FEAT_FGT check to
directly call a generic function instead of providing a trivial specific
one. The #ifdef is moved into the function, and rewritten as a proper C
if statement.
We need to force the compiler to inline that function, otherwise the
optimisation won't work, once we exceed a certain number of callers.
This starts with FEAT_FGT, but all the other features will be moved over
eventually, in separate patches.
For all features checked this way, we delay the panic() until after
every feature has been checked, to list them all during one run.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: Ic576922ff2c4f8d3c1b87b5843b3626729fe4514
The FEATURE_DETECTION functionality had some definitions in a header
file, although they were only used internally in the .c file.
Move them over there, since there are of no interest to other users.
Also use the opportuntiy to rename the less telling FEAT_STATE_[12]
names, and let the "0" case join the game. We use DISABLED, ALWAYS, and
CHECK now, so that the casual reader has some idea what those numbers
are supposed to mean.
feature_panic() becomes "static inline", since disabling all features
makes it unused, so the compiler complains otherwise.
Finally add a new category "cpufeat" to cover CPU feature related
changes.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Change-Id: If0c8ba91ad22440260ccff383c33bdd055eefbdc
FEAT_RNG_TRAP introduces support for EL3 trapping of reads of the
RNDR and RNDRRS registers, which is enabled by setting the
SCR_EL3.TRNDR bit. This patch adds a new build flag
ENABLE_FEAT_RNG_TRAP that enables the feature.
This feature is supported only in AArch64 state from Armv8.5 onwards.
Signed-off-by: Juan Pablo Conde <juanpablo.conde@arm.com>
Change-Id: Ia9f17aef3444d3822bf03809036a1f668c9f2d89
This change adds "FEAT_TRBE" to be part of feature detection mechanism.
Previously feature enablement flags were of boolean type, containing
either 0 or 1. With the introduction of feature detection procedure
we now support three states for feature enablement build flags(0 to 2).
Accordingly, "ENABLE_TRBE_FOR_NS" flag is now modified from boolean
to numeric type to align with the feature detection.
Change-Id: I53d3bc8dc2f6eac63feef22dfd627f3a48480afc
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
This change adds "FEAT_BRBE" to be part of feature detection mechanism.
Previously feature enablement flags were of boolean type, possessing
either 0 or 1. With the introduction of feature detection procedure
we now support three states for feature enablement build flags(0 to 2).
Accordingly, "ENABLE_BRBE_FOR_NS" flag is now modified from boolean
to numeric type to align with the feature detection.
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Change-Id: I1eb52863b4afb10b808e2f0b6584a8a210d0f38c
The current implementation uses plat_arm API under generic code.
"plat_arm" API is a convention used with Arm common platform layer
and is reserved for that purpose. In addition, the function has a
weak definition which is not encouraged in TF-A.
Henceforth, removing the weak API with a configurable macro "TWED_DELAY"
of numeric data type in generic code and simplifying the implementation.
By default "TWED_DELAY" is defined to zero, and the delay value need to
be explicitly set by the platforms during buildtime.
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Change-Id: I25cd6f628e863dc40415ced3a82d0662fdf2d75a
This patch adds architectural features detection procedure to ensure
features enabled are present in the given hardware implementation.
It verifies whether the architecture build flags passed during
compilation match the respective features by reading their ID
registers. It reads through all the enabled feature specific ID
registers at once and panics in case of mismatch(feature enabled
but not implemented in PE).
Feature flags are used at sections (context_management,
save and restore routines of registers) during context switch.
If the enabled feature flag is not supported by the PE, it causes an
exception while saving or restoring the registers guarded by them.
With this mechanism, the build flags are validated at an early
phase prior to their usage, thereby preventing any undefined action
under their control.
This implementation is based on tristate approach for each feature and
currently FEAT_STATE=0 and FEAT_STATE=1 are covered as part of this
patch. FEAT_STATE=2 is planned for phase-2 implementation and will be
taken care separately.
The patch has been explicitly tested, by adding a new test_config
with build config enabling majority of the features and detected
all of them under FVP launched with parameters enabling v8.7 features.
Note: This is an experimental procedure and the mechanism itself is
guarded by a macro "FEATURE_DETECTION", which is currently being
disabled by default.
The "FEATURE_DETECTION" macro is documented and the platforms are
encouraged to make use of this diagnostic tool by enabling this
"FEATURE_DETECTION" flag explicitly and get used to its behaviour
during booting before the procedure gets mandated.
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
Change-Id: Ia23d95430fe82d417a938b672bfb5edc401b0f43