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>
Implements mitigation for CVE-2024-5660 that affects Cortex-X1
revisions r0p0, r1p0, r1p1, r1p2.
The workaround is to disable the hardware page aggregation at
EL3 by setting CPUECTLR_EL1[46] = 1'b1.
Public Documentation:
https://developer.arm.com/Arm%20Security%20Center/Arm%20CPU%20Vulnerability%20CVE-2024-5660
Change-Id: I3124db3980f2786412369a010ca6abbbbaa3b601
Signed-off-by: Sona Mathew <sonarebecca.mathew@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>
Testing:
- Manual comparison of disassembly with and without conversion.
- Using the test script in gerrit - 19136
- Building with errata and stepping through from ArmDS and running tftf.
Change-Id: Ie3909ef51c28a24728752a08ddf96a48d87d3cd7
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>
In assembly code, BIT macro is used with a preceding hash #. Let's
update Cortex X1 code to follow the same convention. Excluding hash
doesn't cause compilation to fail or emit incorrect code.
Signed-off-by: Okash Khawaja <okash@google.com>
Change-Id: If304cdf90542d2edcab3e2d66cd7e905ff7fd047
This patch adds workarounds for following cortex-x1 errata:
- 1821534 (CatB)
- 1688305 (CatB)
- 1827429 (CatB)
SDEN can be found here:
https://developer.arm.com/documentation/SDEN1401782/latest
Signed-off-by: Okash Khawaja <okash@google.com>
Change-Id: I10ebe8d5c56a6d273820bb2c682f21bf98daa7a5
This patch adds basic CPU library code to support Cortex-X1 CPU in TF-A.
Follow-up patches will add selected errata workarounds for this CPU.
Signed-off-by: Okash Khawaja <okash@google.com>
Change-Id: I4a3d50a98bf55a555bfaefeed5c7b88a35e3bc21