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[v2,0/6] target/arm: Implement FEAT_XS

Message ID 20241211144440.2700268-1-peter.maydell@linaro.org
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Series target/arm: Implement FEAT_XS | expand

Message

Peter Maydell Dec. 11, 2024, 2:44 p.m. UTC 
Based-on: 20241210160452.2427965-1-peter.maydell@linaro.org
("target/arm: Pull TLBI insns out to their own source file")

The FEAT_XS feature was introduced in ARMv8.7: it adds a new memory
attribute XS which indicates that a memory access could take longer
than usual to complete, and also adds instruction variants for TLBI
maintenance and DSB.

For QEMU, we don't have any concept of "really slow memory regions",
so we don't need to implement the XS attribute to do anything
special. So we only need to implement the new TLBI, DSB, etc as doing
the same as the non-XS versions.

This is a respin of Manos' v1 patchseries. In particular:
 * patch 1 adds support for the fine-grained-trap handling for
   the new TLBI NXS insns
 * patches 2 and 3 implement the actual TLB insns in a different
   way to v1: we add a new ARM_CP_ADD_TLBI_NXS cpreg type flag
   which we can mark the existing TLBI insns with; the core
   cpregs machinery will then autogenerate the TLBI NXS cpreg
   when FEAT_XS is present. The aim is to avoid having a lot
   of mostly-duplicate cpreg structs and arrays.
 * patches 4, 5, 6 have only minor changes from v1 to address
   issues raised in code review

thanks
-- PMM

Manos Pitsidianakis (3):
  target/arm: Add decodetree entry for DSB nXS variant
  target/arm: Enable FEAT_XS for the max cpu
  tests/tcg/aarch64: add system test for FEAT_XS

Peter Maydell (3):
  target/arm: Implement fine-grained-trap handling for FEAT_XS
  target/arm: Add ARM_CP_ADD_TLBI_NXS type flag for NXS insns
  target/arm: Add ARM_CP_ADD_TLBI_NXS type flag to TLBI insns

 docs/system/arm/emulation.rst      |   1 +
 target/arm/cpregs.h                |  80 +++++++-----
 target/arm/cpu-features.h          |   5 +
 target/arm/tcg/a64.decode          |   3 +
 target/arm/helper.c                |  30 ++++-
 target/arm/tcg/cpu64.c             |   1 +
 target/arm/tcg/op_helper.c         |  11 +-
 target/arm/tcg/tlb-insns.c         | 202 ++++++++++++++++++-----------
 target/arm/tcg/translate-a64.c     |   9 ++
 tests/tcg/aarch64/system/feat-xs.c |  27 ++++
 10 files changed, 259 insertions(+), 110 deletions(-)
 create mode 100644 tests/tcg/aarch64/system/feat-xs.c