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arm64/acpi: Give the real PA limit to ACPI
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Authored by scottph on Aug 20 2020, 6:56 AM.

Details

Summary

Read PA bits from ID_AA64MMFR0_EL1.PARange.

MFC after: 1 week
Sponsored by: Ampere Computing, Inc.

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Repository
rS FreeBSD src repository
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Automatic diff as part of commit; lint not applicable.
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Event Timeline

You should use get_kernel_reg to read the ID registers when we need a common version over all CPUs. It's not going to affect it here, but when use later in the boot it can as on a big.LITTLE system these ID registers can sometimes be different across the different core types.

sys/arm64/acpica/acpi_machdep.c
252 ↗(On Diff #76021)

This should be ID_AA64MMFR0_PARange_VAL(mmfr0) Maybe with >> ID_AA64MMFR0_PARange_SHIFT, although the shift is 0 so it might be easier to add a comment to make this knowledge explicit.

scottph marked an inline comment as done.
This revision is now accepted and ready to land.Aug 21 2020, 9:55 AM
markj added inline comments.
sys/arm64/acpica/acpi_machdep.c
271 ↗(On Diff #76051)

You might print the value itself in this message.

This revision was automatically updated to reflect the committed changes.