In pmccntr_op_finish() and pmevcntr_op_finish() we calculate the next
point at which we will get an overflow and need to fire the PMU
interrupt or set the overflow flag. We do this by calculating the
number of nanoseconds to the overflow event and then adding it to
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL). However, we don't check
whether that signed addition overflows, which can happen if the next
PMU interrupt would happen massively far in the future (250 years or
more).
Since QEMU assumes that "when the QEMU_CLOCK_VIRTUAL rolls over" is
"never", the sensible behaviour in this situation is simply to not
try to set the timer if it would be beyond that point. Detect the
overflow, and skip setting the timer in that case.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822132358.3524971-7-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The logic in pmu_counter_enabled() for handling the 'prohibit event
counting' bits MDCR_EL2.HPMD and MDCR_EL3.SPME is written in a way
that assumes that EL2 is never Secure. This used to be true, but the
architecture now permits Secure EL2, and QEMU can emulate this.
Refactor the prohibit logic so that we effectively OR together
the various prohibit bits when they apply, rather than trying to
construct an if-else ladder where any particular state of the CPU
ends up in exactly one branch of the ladder.
This fixes the Secure EL2 case and also is a better structure for
adding the PMUv8.5 bits MDCR_EL2.HCCD and MDCR_EL3.SCCD.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822132358.3524971-6-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The architecture requires that if PMCR.LC is set (for a 64-bit cycle
counter) then PMCR.D (which enables the clock divider so the counter
ticks every 64 cycles rather than every cycle) should be ignored. We
were always honouring PMCR.D; fix the bug so we correctly ignore it
in this situation.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822132358.3524971-5-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The PMU cycle and event counter infrastructure design requires that
operations on the PMU register fields are wrapped in pmu_op_start()
and pmu_op_finish() calls (or their more specific pmmcntr and
pmevcntr equivalents). This includes any changes to registers which
affect whether the counter should be enabled or disabled, but we
forgot to do this.
The effect of this bug is that in sequences like:
* disable the cycle counter (PMCCNTR) using the PMCNTEN register
* write a value such as 0xfffff000 to the PMCCNTR
* restart the counter by writing to PMCNTEN
the value written to the cycle counter is corrupted, and it starts
counting from the wrong place. (Essentially, we fail to record that
the QEMU_CLOCK_VIRTUAL timestamp when the counter should be considered
to have started counting is the point when PMCNTEN is written to enable
the counter.)
Add the necessary bracketing calls, so that updates to the various
registers which affect whether the PMU is counting are handled
correctly.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220822132358.3524971-4-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In Armv8.6, a new AArch32 ID register ID_DFR1 is defined; implement
it. We don't have any CPUs with features that they need to advertise
here yet, but plumbing in the ID register gives it the right name
when debugging and will help in future when we do add a CPU that
has non-zero ID_DFR1 fields.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220819110052.2942289-5-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
In the AArch32 ID register scheme, coprocessor registers with
encoding cp15, 0, c0, c{0-7}, {0-7} are all in the space covered by
what in v6 and v7 was called the "CPUID scheme", and are supposed to
RAZ if they're not allocated to a specific ID register. For our
pre-v8 CPUs we get this right, because the regdefs in
id_pre_v8_midr_cp_reginfo[] cover these RAZ requirements. However
for v8 we failed to put in the necessary patterns to cover this, so
we end up UNDEFing on everything we didn't have an ID register for.
This is a problem because in Armv8 some encodings in 0, c0, c3, {0-7}
are now being used for new ID registers, and guests might thus start
trying to read them. (We already have one of these: ID_PFR2.)
For v8 CPUs, we already have regdefs for 0, c0, c{0-2}, {0-7} (that
is, the space is completely allocated with no reserved spaces). Add
entries to v8_idregs[] covering 0, c0, c3, {0-7}:
* c3, {0-2} is the reserved AArch32 space corresponding to the
AArch64 MVFR[012]_EL1
* c3, {3,5,6,7} are reserved RAZ for both AArch32 and AArch64
(in fact some of these are given defined meanings in Armv8.6,
but we don't implement them yet)
* c3, 4 is ID_PFR2 (already defined)
We then programmatically add RAZ patterns for AArch32 for
0, c0, c{4..15}, {0-7}:
* c4-c7 are unused, and not shared with AArch64 (these
are the encodings corresponding to where the AArch64
specific ID registers live in the system register space)
* c8-c15 weren't required to RAZ in v6/v7, but v8 extends
the AArch32 reserved-should-RAZ space to cover these;
the equivalent area of the AArch64 sysreg space is not
defined as must-RAZ
Note that the architecture allows some registers in this space
to return an UNKNOWN value; we always return 0.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220819110052.2942289-2-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When the user queries CPU models via QMP there is a 'deprecated' flag
present, however, this is not done for the CLI '-cpu help' command.
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Change the representation of the TCR_EL* registers in the CPU state
struct from struct TCR to uint64_t. This allows us to drop the
custom vmsa_ttbcr_raw_write() function, moving the "enforce RES0"
checks to their more usual location in the writefn
vmsa_ttbcr_write(). We also don't need the resetfn any more.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220714132303.1287193-7-peter.maydell@linaro.org
We have a bug in our handling of accesses to the AArch32 VTCR
register on big-endian hosts: we were not adjusting the part of the
uint64_t field within TCR that the generated code would access. That
can be done with offsetoflow32(), by using an ARM_CP_STATE_BOTH cpreg
struct, or by defining a full set of read/write/reset functions --
the various other TCR cpreg structs used one or another of those
strategies, but for VTCR we did not, so on a big-endian host VTCR
accesses would touch the wrong half of the register.
Use offsetoflow32() in the VTCR register struct. This works even
though the field in the CPU struct is currently a struct TCR, because
the first field in that struct is the uint64_t raw_tcr.
None of the other TCR registers have this bug -- either they are
AArch64 only, or else they define resetfn, writefn, etc, and
expect to be passed the full struct pointer.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220714132303.1287193-5-peter.maydell@linaro.org
The regime_tcr() function returns a pointer to a struct TCR
corresponding to the TCR controlling a translation regime. The
struct TCR has the raw value of the register, plus two fields mask
and base_mask which are used as a small optimization in the case of
32-bit short-descriptor lookups. Almost all callers of regime_tcr()
only want the raw register value. Define and use a new
regime_tcr_value() function which returns only the raw 64-bit
register value.
This is a preliminary to removing the 32-bit short descriptor
optimization -- it only saves a handful of bit operations, which is
tiny compared to the overhead of doing a page table walk at all, and
the TCR struct is awkward and makes fixing
https://gitlab.com/qemu-project/qemu/-/issues/1103 unnecessarily
difficult.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220714132303.1287193-2-peter.maydell@linaro.org
This new behaviour is in the ARM pseudocode function
AArch64.CheckFPAdvSIMDEnabled, which applies to AArch32
via AArch32.CheckAdvSIMDOrFPEnabled when the EL to which
the trap would be delivered is in AArch64 mode.
Given that ARMv9 drops support for AArch32 outside EL0, the trap EL
detection ought to be trivially true, but the pseudocode still contains
a number of conditions, and QEMU has not yet committed to dropping A32
support for EL[12] when v9 features are present.
Since the computation of SME_TRAP_NONSTREAMING is necessarily different
for the two modes, we might as well preserve bits within TBFLAG_ANY and
allocate separate bits within TBFLAG_A32 and TBFLAG_A64 instead.
Note that DDI0616A.a has typos for bits [22:21] of LD1RO in the table
of instructions illegal in streaming mode.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220708151540.18136-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The target/arm/helper.c file is very long and is a grabbag of all
kinds of functionality. We have already a debug_helper.c which has
code for implementing architectural debug. Move the code which
defines the debug-related system registers out to this file also.
This affects the define_debug_regs() function and the various
functions and arrays which are used only by it.
The functions raw_write() and arm_mdcr_el2_eff() and
define_debug_regs() now need to be global rather than local to
helper.c; everything else is pure code movement.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220630194116.3438513-3-peter.maydell@linaro.org
Perform the cleanup in the FIXME comment in common_semi_gdb_syscall.
Do not modify guest registers until the syscall is complete,
which in the gdbstub case is asynchronous.
In the synchronous non-gdbstub case, use common_semi_set_ret
to set the result. Merge set_swi_errno into common_semi_cb.
Rely on the latter for combined return value / errno setting.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
When Streaming SVE mode is enabled, the size is taken from
SMCR_ELx instead of ZCR_ELx. The format is shared, but the
set of vector lengths is not. Further, Streaming SVE does
not require any particular length to be supported.
Adjust sve_vqm1_for_el to pass the current value of PSTATE.SM
to the new function.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220620175235.60881-19-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This will be used for both Normal and Streaming SVE, and the value
does not necessarily come from ZCR_ELx. While we're at it, emphasize
the units in which the value is returned.
Patch produced by
git grep -l sve_zcr_len_for_el | \
xargs -n1 sed -i 's/sve_zcr_len_for_el/sve_vqm1_for_el/g'
and then adding a function comment.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220607203306.657998-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The bitmap need only hold 15 bits; bitmap is over-complicated.
We can simplify operations quite a bit with plain logical ops.
The introduction of SVE_VQ_POW2_MAP eliminates the need for
looping in order to search for powers of two. Simply perform
the logical ops and use count leading or trailing zeros as
required to find the result.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220607203306.657998-12-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This check is buried within arm_hcr_el2_eff(), but since we
have to have the explicit check for CPTR_EL2.TZ, we might as
well just check it once at the beginning of the block.
Once this is done, we can test HCR_EL2.{E2H,TGE} directly,
rather than going through arm_hcr_el2_eff().
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220607203306.657998-9-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>