Re: [Qemu-devel] [PATCH v4 0/5] add ACPI node for fw_cfg on pc and arm

[Michael S. Tsirkin]

On Sun, Sep 27, 2015 at 05:28:57PM -0400, Gabriel L. Somlo wrote:
> New since v3:
> 
>       - rebased to work on top of 87e896ab (introducing pc-*-25 classes),
>         inserting fw_cfg acpi node only for machines >= 2.5.
> 
>       - reintroduce _STA with value 0x0B (bit 2 for u/i visibility turned
>         off to avoid Windows complaining -- thanks Igor for catching that!)
> 
> If there's any other feedback besides questions regarding the
> appropriateness of "QEMU0002" as the value of _HID, please don't hesitate!
> 
> Thanks much,
>   --Gabriel

How does /proc/ioports look before and after this patch?


> >New since v2:
> >
> >     - pc/i386 node in ssdt only on machine types *newer* than 2.4
> >       (as suggested by Eduardo)
> >
> >I appreciate any further comments and reviews. Hopefully we can make
> >this palatable for upstream, modulo the lingering concerns about whether
> >"QEMU0002" is ok to use as the value of _HID, which I'll hopefully get
> >sorted out with the kernel crew...
> >
> >>New since v1:
> >>
> >>    - expose control register size (suggested by Marc Marí)
> >>
> >>    - leaving out _UID and _STA fields (thanks Shannon & Igor)
> >>
> >>    - using "QEMU0002" as the value of _HID (thanks Michael)
> >>
> >>    - added documentation blurb to docs/specs/fw_cfg.txt
> >>      (mainly to record usage of the "QEMU0002" string with fw_cfg).
> >>
> >>> This series adds a fw_cfg device node to the SSDT (on pc), or to the
> >>> DSDT (on arm).
> >>>
> >>>   - Patch 1/3 moves (and renames) the BIOS_CFG_IOPORT (0x510)
> >>>     define from pc.c to pc.h, so that it could be used from
> >>>     acpi-build.c in patch 2/3.
> >>> 
> >>>   - Patch 2/3 adds a fw_cfg node to the pc SSDT.
> >>> 
> >>>   - Patch 3/3 adds a fw_cfg node to the arm DSDT.
> >>>
> >>> I made up some names - "FWCF" for the node name, and "FWCF0001"
> >>> for _HID; no idea whether that's appropriate, or how else I should
> >>> figure out what to use instead...
> >>>
> >>> Also, using scope "\\_SB", based on where fw_cfg shows up in the
> >>> output of "info qtree". Again, if that's wrong, please point me in
> >>> the right direction.
> >>>
> >>> Re. 3/3 (also mentioned after the commit blurb in the patch itself),
> >>> I noticed none of the other DSDT entries contain a _STA field, wondering
> >>> why it would (not) make sense to include that, same as on the PC.
> 
> Gabriel L. Somlo (5):
>   fw_cfg: expose control register size in fw_cfg.h
>   pc: fw_cfg: move ioport base constant to pc.h
>   acpi: pc: add fw_cfg device node to ssdt
>   acpi: arm: add fw_cfg device node to dsdt
>   fw_cfg: document ACPI device node information
> 
>  docs/specs/fw_cfg.txt     |  9 +++++++++
>  hw/arm/virt-acpi-build.c  | 15 +++++++++++++++
>  hw/i386/acpi-build.c      | 23 +++++++++++++++++++++++
>  hw/i386/pc.c              |  5 ++---
>  hw/i386/pc_piix.c         |  1 +
>  hw/i386/pc_q35.c          |  1 +
>  hw/nvram/fw_cfg.c         |  8 +++++---
>  include/hw/i386/pc.h      |  3 +++
>  include/hw/nvram/fw_cfg.h |  3 +++
>  9 files changed, 62 insertions(+), 6 deletions(-)
> 
> -- 
> 2.4.3