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| H A D | cpu.c | diff eb851c1151252158ab5b5917c5d386e1d69de3a2 Wed Apr 27 04:01:17 CDT 2022 Damien Hedde <damien.hedde@greensocs.com> target/arm: Disable cryptographic instructions when neon is disabled
As of now, cryptographic instructions ISAR fields are never cleared so
we can end up with a cpu with cryptographic instructions but no
floating-point/neon instructions which is not a possible configuration
according to Arm specifications.
In QEMU, we have 3 kinds of cpus regarding cryptographic instructions:
+ no support
+ cortex-a57/a72: cryptographic extension is optional,
floating-point/neon is not.
+ cortex-a53: crytographic extension is optional as well as
floating-point/neon. But cryptographic requires
floating-point/neon support.
Therefore we can safely clear the ISAR fields when neon is disabled.
Note that other Arm cpus seem to follow this. For example cortex-a55 is
like cortex-a53 and cortex-a76/cortex-a710 are like cortex-a57/a72.
Signed-off-by: Damien Hedde <damien.hedde@greensocs.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220427090117.6954-1-damien.hedde@greensocs.com
[PMM: fixed commit message typos]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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