diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2020-02-10 12:01:46 +0000 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2020-02-13 14:30:51 +0000 |
| commit | dc7a88d0810ad272bdcd2e0869359af78fdd9114 (patch) | |
| tree | 9a4c94c9e41811cddbf7a6318e26e6787260e4f2 /target/arm | |
| parent | 759f0f87e34fe63a475d926ea6db88d11d2cd018 (diff) | |
target/arm: Implement ARMv8.1-VMID16 extension
The ARMv8.1-VMID16 extension extends the VMID from 8 bits to 16 bits:
* the ID_AA64MMFR1_EL1.VMIDBits field specifies whether the VMID is
8 or 16 bits
* the VMID field in VTTBR_EL2 is extended to 16 bits
* VTCR_EL2.VS lets the guest specify whether to use the full 16 bits,
or use the backwards-compatible 8 bits
For QEMU implementing this is trivial:
* we do not track VMIDs in TLB entries, so we never use the VMID field
* we treat any write to VTTBR_EL2, not just a change to the VMID field
bits, as a "possible VMID change" that causes us to throw away TLB
entries, so that code doesn't need changing
* we allow the guest to read/write the VTCR_EL2.VS bit already
So all that's missing is the ID register part: report that we support
VMID16 in our 'max' CPU.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200210120146.17631-1-peter.maydell@linaro.org
Diffstat (limited to 'target/arm')
| -rw-r--r-- | target/arm/cpu64.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 1359564c55..f0d98bc79d 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -674,6 +674,7 @@ static void aarch64_max_initfn(Object *obj) t = FIELD_DP64(t, ID_AA64MMFR1, LO, 1); t = FIELD_DP64(t, ID_AA64MMFR1, VH, 1); t = FIELD_DP64(t, ID_AA64MMFR1, PAN, 2); /* ATS1E1 */ + t = FIELD_DP64(t, ID_AA64MMFR1, VMIDBITS, 2); /* VMID16 */ cpu->isar.id_aa64mmfr1 = t; t = cpu->isar.id_aa64mmfr2; |