[00/11] Add support for the T-Head vendor extensions

Message

Christoph Müllner Sept. 6, 2022, 12:22 p.m. UTC

From: Christoph Müllner <[e-mail]>

This series introduces support for the T-Head vendor extensions,
which are implemented e.g. in the XuanTie C906 and XuanTie C910
processors:
* XTheadBa
* XTheadBb
* XTheadBs
* XTheadCmo
* XTheadCondMov
* XTheadFMemIdx
* XTheadMac
* XTheadMemIdx
* XTheadMemPair
* XTheadSync

The xthead* extensions are documented here:
https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.0.0/xthead-2022-09-05-2.0.0.pdf

The "th." instruction prefix prevents future conflicts with standard
extensions and has been documentented in a PR for the RISC-V toolchain
conventions:
  https://github.com/riscv-non-isa/riscv-toolchain-conventions/pull/19

The goal of this patchset is to provide access to these instruction
so that compilers/users can optimize SW accordingly.

Note, that the T-Head vendor extensions do not contain all
vendor-specific functionality of the T-Head SoCs (e.g. no vendor-specific
CSRs are included). Instead the extensions cover coherent functionality,
that is exposed to S and U mode.

To enable the extensions above, the following two methods are possible:
* add the extension to the arch string (e.g.
* QEMU_CPU="any,xtheadcmo=true,xtheadsync=true")
* implicitly select the extensions via CPU selection (e.g.
* QEMU_CPU="thead-c910")

This patchset attempts to minimize code changes in
generic/infrastructure code.
This patchset allows to boot the Xuantie Linux kernel.

Christoph Müllner (11):
  riscv: Add privilege level to DisasContext
  RISC-V: Adding T-Head CMO instructions
  RISC-V: Adding T-Head SYNC instructions
  RISC-V: Adding T-Head Bitmanip instructions
  RISC-V: Adding T-Head CondMov instructions
  RISC-V: Adding T-Head multiply-accumulate instructions
  RISC-V: Adding T-Head XMAE support
  RISC-V: Adding T-Head MemPair extension
  RISC-V: Adding T-Head MemIdx extension
  RISC-V: Adding T-Head FMemIdx extension
  RISC-V: Add initial support for T-Head C906 and C910 CPUs

 target/riscv/cpu.c                         |  43 +
 target/riscv/cpu.h                         |  14 +
 target/riscv/cpu_helper.c                  |   6 +-
 target/riscv/cpu_vendorid.h                |   6 +
 target/riscv/insn_trans/trans_xthead.c.inc | 874 +++++++++++++++++++++
 target/riscv/meson.build                   |  10 +
 target/riscv/translate.c                   |  42 +-
 target/riscv/xtheadba.decode               |  46 ++
 target/riscv/xtheadbb.decode               |  62 ++
 target/riscv/xtheadbs.decode               |  32 +
 target/riscv/xtheadcmo.decode              |  43 +
 target/riscv/xtheadcondmov.decode          |  33 +
 target/riscv/xtheadfmemidx.decode          |  34 +
 target/riscv/xtheadmac.decode              |  30 +
 target/riscv/xtheadmemidx.decode           |  73 ++
 target/riscv/xtheadmempair.decode          |  29 +
 target/riscv/xtheadsync.decode             |  25 +
 17 files changed, 1397 insertions(+), 5 deletions(-)
 create mode 100644 target/riscv/cpu_vendorid.h
 create mode 100644 target/riscv/insn_trans/trans_xthead.c.inc
 create mode 100644 target/riscv/xtheadba.decode
 create mode 100644 target/riscv/xtheadbb.decode
 create mode 100644 target/riscv/xtheadbs.decode
 create mode 100644 target/riscv/xtheadcmo.decode
 create mode 100644 target/riscv/xtheadcondmov.decode
 create mode 100644 target/riscv/xtheadfmemidx.decode
 create mode 100644 target/riscv/xtheadmac.decode
 create mode 100644 target/riscv/xtheadmemidx.decode
 create mode 100644 target/riscv/xtheadmempair.decode
 create mode 100644 target/riscv/xtheadsync.decode