In previous versions of the Arm architecture, the frequency of the
generic timers as reported in CNTFRQ_EL0 could be any IMPDEF value,
and for QEMU we picked 62.5MHz, giving a timer tick period of 16ns.
In Armv8.6, the architecture standardized this frequency to 1GHz.
Because there is no ID register feature field that indicates whether
a CPU is v8.6 or that it ought to have this counter frequency, we
implement this by changing our default CNTFRQ value for all CPUs,
with exceptions for backwards compatibility:
* CPU types which we already implement will retain the old
default value. None of these are v8.6 CPUs, so this is
architecturally OK.
* CPUs used in versioned machine types with a version of 9.0
or earlier will retain the old default value.
The upshot is that the only CPU type that changes is 'max'; but any
new type we add in future (whether v8.6 or not) will also get the new
1GHz default.
It remains the case that the machine model can override the default
value via the 'cntfrq' QOM property (regardless of the CPU type).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240426122913.3427983-5-peter.maydell@linaro.org
FEAT_ETS2 is a tighter set of guarantees about memory ordering
involving translation table walks than the old FEAT_ETS; FEAT_ETS has
been retired from the Arm ARM and the old ID_AA64MMFR1.ETS == 1
now gives no greater guarantees than ETS == 0.
FEAT_ETS2 requires:
* the virtual address of a load or store that appears in program
order after a DSB cannot be translated until after the DSB
completes (section B2.10.9)
* TLB maintenance operations that only affect translations without
execute permission are guaranteed complete after a DSB
(R_BLDZX)
* if a memory access RW2 is ordered-before memory access RW2,
then RW1 is also ordered-before any translation table walk
generated by RW2 that generates a Translation, Address size
or Access flag fault (R_NNFPF, I_CLGHP)
As with FEAT_ETS, QEMU is already compliant, because we do not
reorder translation table walk memory accesses relative to other
memory accesses, and we always guarantee to have finished TLB
maintenance as soon as the TLB op is done.
Update the documentation to list FEAT_ETS2 instead of the
no-longer-existent FEAT_ETS, and update the 'max' CPU ID registers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240418152004.2106516-4-peter.maydell@linaro.org
Move the code to a separate file so that we do not have to compile
it anymore if CONFIG_ARM_V7M is not set.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-id: 20240308141051.536599-2-thuth@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add the Cortex-R52 IMPDEF sysregs, by defining them here and
also by enabling the AUXCR feature which defines the ACTLR
and HACTLR registers. As is our usual practice, we make these
simple reads-as-zero stubs for now.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240206132931.38376-4-peter.maydell@linaro.org
The Cortex-R52 implements the Configuration Base Address Register
(CBAR), as a read-only register. Add ARM_FEATURE_CBAR_RO to this CPU
type, so that our implementation provides the register and the
associated qdev property.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240206132931.38376-3-peter.maydell@linaro.org
QEMU coding style recommends using structure typedefs.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
According to the technical reference manual, the Cortex-A9
has a Perfomance Unit Monitor (PMU):
https://developer.arm.com/documentation/100511/0401/performance-monitoring-unit/about-the-performance-monitoring-unit
The Cortex-A8 does also.
We already already define the PMU registers when emulating the
Cortex-A8 and Cortex-A9, because we put them in v7_cp_reginfo[]
rather than guarding them behind ARM_FEATURE_PMU. So the only thing
that setting the feature bit changes is that the registers actually
do something.
Enable ARM_FEATURE_PMU for Cortex-A8 and Cortex-A9, to avoid
this anomaly.
(The A8 and A9 PMU predates the standardisation of ID_DFR0.PerfMon,
so the field there is 0, but the PMU is still present.)
Signed-off-by: Nikita Ostrenkov <n.ostrenkov@gmail.com>
Message-id: 20231112165658.2335-1-n.ostrenkov@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: tweaked commit message; also enable PMU for A8]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
FEAT_HPMN0 is a small feature which defines that it is valid for
MDCR_EL2.HPMN to be set to 0, meaning "no PMU event counters provided
to an EL1 guest" (previously this setting was reserved). QEMU's
implementation almost gets HPMN == 0 right, but we need to fix
one check in pmevcntr_is_64_bit(). That is enough for us to
advertise the feature in the 'max' CPU.
(We don't need to make the behaviour conditional on feature
presence, because the FEAT_HPMN0 behaviour is within the range
of permitted UNPREDICTABLE behaviour for a non-FEAT_HPMN0
implementation.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230921185445.3339214-1-peter.maydell@linaro.org
This feature allows the operating system to set TCR_ELx.HWU*
to allow the implementation to use the PBHA bits from the
block and page descriptors for for IMPLEMENTATION DEFINED
purposes. Since QEMU has no need to use these bits, we may
simply ignore them.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230811214031.171020-11-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
move the module containing cpu models definitions
for 32bit TCG-only CPUs to tcg/ and rename it for clarity.
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20230426180013.14814-8-farosas@suse.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
