Re: [PATCH 0/5] target/riscv: support Debug 0.13 and 1.0

[Chao Liu <chao.liu@processmission.com>]

Hi Daniel,

On Thu, Aug 20, 2026 at 08:01:39AM +0800, Daniel Henrique Barboza wrote:
> Ping
> 
> 
> This is the series I talked about in our call last night/earlier today.
> 
> The v9 of the riscv-server-ref work was rebased on top of it, along with Chao's
> sdext patches.  As soon as we get this queued I think I'll re-send Chao's
> work next.
Thanks for continuing to drive the sdext work. I don’t have much time to dedicate
to it at the moment, but I’ll do my best to help with the review.

Cheers,
Chao
> 
> 
> Cheers,
> Daniel
> 
> On 8/5/2026 3:25 PM, Daniel Henrique Barboza wrote:
> > Hi,
> > 
> > This short series adds support for Debug 0.13 and Debug 1.0.  The
> > motivation is simple: we need Debug 1.0 to complete tue upstreaming of
> > sdext, which is already fully reviewed and acked for awhile [1], and
> > then proceed with the upstreaming of the RISC-V Server Ref board
> > (currently on v8: [2]).
> > 
> > The work is based in section 1.2.1.2 "Incompatible Changes from 0.13 to
> > 1.0" of the ratified 1.0 spec [3].  It ended being simpler than
> > anticipated because we don't implement most of the registers/bits that
> > are backwards incompatible.  I added doc changes to explain the
> > rationale used.
> > 
> > After this series:
> > 
> > - 'ext_sdtrig' refers to Debug 1.0.  The legacy 'debug' flag refers to
> >    Debug 0.13;
> > - setting both flags enables Debug 1.0, i.e. 'ext_sdtrig' takes
> >    precedence.
> > 
> > My hope is that this split will make it easier to to move away from
> > Debug 0.13 in the future once there's no more demand for it.
> > 
> > Patches based on master.
> > 
> > [1] https://lore.kernel.org/qemu-devel/cover.1775959096.git.chao.liu.zevorn@gmail.com/
> > [2] https://lore.kernel.org/qemu-devel/20260610214133.1882563-1-daniel.barboza@oss.qualcomm.com/
> > [3] https://docs.riscv.org/reference/debug/v1.0/_attachments/riscv-debug-specification.pdf
> > 
> > Daniel Henrique Barboza (5):
> >    target/riscv: split 'debug' and 'sdtrig' flags
> >    target/riscv/tcg/debug.c: add Debug 1.0 'pending' bit
> >    target/riscv/tcg/debug: adjust 'timing' bit for Debug 1.0
> >    target/riscv/tcg/debug: set tinfo version if sdtrig enabled
> >    docs/specs: add RISC-V CPU Debug support info
> > 
> >   docs/specs/index.rst              |  1 +
> >   docs/specs/riscv-debug.rst        | 68 +++++++++++++++++++++++++++++++
> >   target/riscv/cpu.c                | 21 +++++++---
> >   target/riscv/cpu_cfg_fields.h.inc |  1 +
> >   target/riscv/machine.c            |  2 +-
> >   target/riscv/tcg/csr.c            |  2 +-
> >   target/riscv/tcg/debug.c          | 51 +++++++++++++++++++++--
> >   target/riscv/tcg/debug.h          |  6 ++-
> >   target/riscv/tcg/tcg-cpu.c        |  3 +-
> >   9 files changed, 142 insertions(+), 13 deletions(-)
> >   create mode 100644 docs/specs/riscv-debug.rst
> > 
>