Errata application is painful for performance. For a start, it's done
when the core has just come out of reset, which means branch predictors
and caches will be empty so a branch to a workaround function must be
fetched from memory and that round trip is very slow. Then it also runs
with the I-cache off, which means that the loop to iterate over the
workarounds must also be fetched from memory on each iteration.
We can remove both branches. First, we can simply apply every erratum
directly instead of defining a workaround function and jumping to it.
Currently, no errata that need to be applied at both reset and runtime,
with the same workaround function, exist. If the need arose in future,
this should be achievable with a reset + runtime wrapper combo.
Then, we can construct a function that applies each erratum linearly
instead of looping over the list. If this function is part of the reset
function, then the only "far" branches at reset will be for the checker
functions. Importantly, this mitigates the slowdown even when an erratum
is disabled.
The result is ~50% speedup on N1SDP and ~20% on AArch64 Juno on wakeup
from PSCI calls that end in powerdown. This is roughly back to the
baseline of v2.9, before the errata framework regressed on performance
(or a little better). It is important to note that there are other
slowdowns since then that remain unknown.
Change-Id: Ie4d5288a331b11fd648e5c4a0b652b74160b07b9
Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Errata printing is done directly via generic_errata_report.
This commit removes the unused \_cpu\()_errata_report
functions for all cores, and removes errata_func from cpu_ops.
Change-Id: I04fefbde5f0ff63b1f1cd17c864557a14070d68c
Signed-off-by: Ryan Everett <ryan.everett@arm.com>
This involves replacing:
* the reset_func with the standard cpu_reset_func_{start,end} to apply
errata automatically
* the <cpu>_errata_report with the errata_report_shim to report errata
automatically
...and for each erratum:
* the prologue with the workaround_<type>_start to do the checks and
framework registration automatically
* the epilogue with the workaround_<type>_end
* the checker function with the check_erratum_<type> to make it more
descriptive
It is important to note that the errata workaround and checking
sequences remain unchanged and preserve their git blame. Testing was
conducted by:
* Manual comparison of disassembly of converted functions with non-
converted functions.
aarch64-none-elf-objdump -D <TF-A with
conversion>/build/../release/bl31/bl31.elf
vs
aarch64-none-elf-objdump -D <TF-A with
clean repo>/build/fvp/release/bl31/bl31.elf
* Build for release with all errata flags enabled and ensure the
changes were identical.
CROSS_COMPILE=aarch64-none-elf- make PLAT=fvp \
DEBUG=0 HW_ASSISTED_COHERENCY=0 \
BL33=<tf-a-tests>/build/fvp/debug/tftf.bin \
all fip ERRATA_A35_855472=1
* Build for debug with all errata enabled and step through ArmDS
at reset to ensure all functions are entered.
Change-Id: Ib001e9fc269e60369ccfda0245a3e6247f0d6aaa
Signed-off-by: Sona Mathew <SonaRebecca.Mathew@arm.com>
Under specific conditions, the processor might issue an eviction and an
L2 cache clean operation to the interconnect in the wrong order. Set
the CPUACTLR.ENDCCASCI bit to 1 to avoid this.
Change-Id: Ide7393adeae04581fa70eb9173b742049fc3e050
Signed-off-by: Louis Mayencourt <louis.mayencourt@arm.com>
Enforce full include path for includes. Deprecate old paths.
The following folders inside include/lib have been left unchanged:
- include/lib/cpus/${ARCH}
- include/lib/el3_runtime/${ARCH}
The reason for this change is that having a global namespace for
includes isn't a good idea. It defeats one of the advantages of having
folders and it introduces problems that are sometimes subtle (because
you may not know the header you are actually including if there are two
of them).
For example, this patch had to be created because two headers were
called the same way: e0ea0928d5 ("Fix gpio includes of mt8173 platform
to avoid collision."). More recently, this patch has had similar
problems: 46f9b2c3a2 ("drivers: add tzc380 support").
This problem was introduced in commit 4ecca33988 ("Move include and
source files to logical locations"). At that time, there weren't too
many headers so it wasn't a real issue. However, time has shown that
this creates problems.
Platforms that want to preserve the way they include headers may add the
removed paths to PLAT_INCLUDES, but this is discouraged.
Change-Id: I39dc53ed98f9e297a5966e723d1936d6ccf2fc8f
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Previously the errata reporting was optional for CPU operation
files and this was achieved by making use of weak reference to
resolve to 0 if the symbol is not defined. This is error prone
when adding new CPU operation files and weak references are
problematic when fixing up dynamic relocations. Hence this patch
removes the weak reference and makes it mandatory for the CPU
operation files to define the errata reporting function.
Change-Id: I8af192e19b85b7cd8c7579e52f8f05a4294e5396
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.
NOTE: Files that have been imported by FreeBSD have not been modified.
[0]: https://spdx.org/
Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
Various CPU drivers in ARM Trusted Firmware register functions to handle
power-down operations. At present, separate functions are registered to
power down individual cores and clusters.
This scheme operates on the basis of core and cluster, and doesn't cater
for extending the hierarchy for power-down operations. For example,
future CPUs might support multiple threads which might need powering
down individually.
This patch therefore reworks the CPU operations framework to allow for
registering power down handlers on specific level basis. Henceforth:
- Generic code invokes CPU power down operations by the level
required.
- CPU drivers explicitly mention CPU_NO_RESET_FUNC when the CPU has no
reset function.
- CPU drivers register power down handlers as a list: a mandatory
handler for level 0, and optional handlers for higher levels.
All existing CPU drivers are adapted to the new CPU operations framework
without needing any functional changes within.
Also update firmware design guide.
Change-Id: I1826842d37a9e60a9e85fdcee7b4b8f6bc1ad043
Signed-off-by: Jeenu Viswambharan <jeenu.viswambharan@arm.com>
In the Cortex-A35/A53/A57 CPUs library code, some of the CPU specific
reset operations are skipped if they have already been applied in a
previous invocation of the reset handler. This precaution is not
required, as all these operations can be reapplied safely.
This patch removes the unneeded test-before-set instructions in
the reset handler for these CPUs.
Change-Id: Ib175952c814dc51f1b5125f76ed6c06a22b95167
This patch adds support for ARM Cortex-A35 processor in the CPU
specific framework, as described in the Cortex-A35 TRM (r0p0).
Change-Id: Ief930a0bdf6cd82f6cb1c3b106f591a71c883464
