Re: [Qemu-devel] [PATCH v9 0/5] add ACPI node for fw_cfg on pc and arm

[Igor Mammedov <imammedo@redhat.com>]

On Fri, 19 Feb 2016 13:20:24 -0500
"Gabriel L. Somlo" <somlo@cmu.edu> wrote:

Gerd,

if you are going to apply it, you'll need to update
expected tables for acpi test (rebuild-expected-aml.sh)
as a commit on top of this series.

> Generate an ACPI DSDT node for fw_cfg on pc and arm guests.
> 
> New since v8:
> 
> 	- patch 3/5: on pc/x86, place FWCF node in scope \_SB.PCI0
> 	  (instead of directly under \_SB), to prevent any possible
> 	  resource conflict as might be observed by Windows
> 	  (thanks again to Igor Mammedov for the suggestion!)
> 
> Thanks,
>   --Gabriel
> 
> >New since v7:
> >
> >	- edited commit blurb on 3/5 to match updated content, i.e. that
> >	  the ACPI node is now inserted into the DSDT (no longer the SSDT).
> >	  (Thanks to Igor Mammedov for catching that!)
> >  
> >>New since v6:
> >>	- rebased to fit on top of fb306ff and f264d36, which moved things
> >>	  around in pc's acpi-build.c (only patch 3/5 affected);
> >>	- kernel-side fw_cfg sysfs driver accepted into upstream linux
> >>  
> >>>New since v5:
> >>>
> >>>	- rebased on top of latest QEMU git master
> >>>  
> >>>>New since v4:
> >>>>
> >>>>	- rebased on top of Marc's DMA series
> >>>>	- drop machine compat dependency for insertion into x86/ssdt
> >>>>	  (patch 3/5), following agreement between Igor and Eduardo
> >>>>	- [mm]io register range now covers DMA register as well, if
> >>>>	  available.
> >>>>	- s/bios/firmware in doc file updates
> >>>>  
> >>>>>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!
> >>>>>  
> >>>>>>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 dsdt
>   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      | 29 +++++++++++++++++++++++++++++
>  hw/i386/pc.c              |  5 ++---
>  hw/nvram/fw_cfg.c         |  4 +++-
>  include/hw/i386/pc.h      |  2 ++
>  include/hw/nvram/fw_cfg.h |  3 +++
>  7 files changed, 63 insertions(+), 4 deletions(-)
>