target/arm: Define raw write for PMU CLR registers

Raw writes to PMCNTENCLR and PMCNTENCLR_EL0 incorrectly used their
default write function, which clears written bits instead of writes the
raw value.

PMINTENCLR and PMINTENCLR_EL1 are similar registers, but they instead
had ARM_CP_NO_RAW. Commit 7a0e58fa6487 ("target-arm: Split NO_MIGRATE
into ALIAS and NO_RAW") sugguests ARM_CP_ALIAS should be used instead of
ARM_CP_NO_RAW in such a case:

> We currently mark ARM coprocessor/system register definitions with
> the flag ARM_CP_NO_MIGRATE for two different reasons:
> 1) register is an alias on to state that's also visible via
>    some other register, and that other register is the one
>    responsible for migrating the state
> 2) register is not actually state at all (for instance the TLB
>    or cache maintenance operation "registers") and it makes no
>    sense to attempt to migrate it or otherwise access the raw state
>
> This works fine for identifying which registers should be ignored
> when performing migration, but we also use the same functions for
> synchronizing system register state between QEMU and the kernel
> when using KVM. In this case we don't want to try to sync state
> into registers in category 2, but we do want to sync into registers
> in category 1, because the kernel might have picked a different
> one of the aliases as its choice for which one to expose for
> migration.

These registers fall in category 1 (ARM_CP_ALIAS), not category 2
(ARM_CP_NO_RAW).

ARM_CP_NO_RAW also has another undesired side effect that hides
registers from GDB.

Properly set raw write functions and drop the ARM_CP_NO_RAW flag from
PMINTENCLR and PMINTENCLR_EL1; this fixes GDB/KVM state synchronization
of PMCNTENCLR and PMCNTENCLR_EL0, and exposes all these four registers
to GDB.

It is not necessary to add ARM_CP_ALIAS to these registers because the
flag is already set.

Signed-off-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Message-id: 20250531-clr-v3-1-377f9bf1746d@rsg.ci.i.u-tokyo.ac.jp
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

0 files changed, 0 insertions, 0 deletions