Re: [Qemu-devel] [PATCH for 2.5? 1/1] DSDT: add floppy-related objects

[Igor Mammedov]

On Mon, 14 Dec 2015 18:11:53 +0300
"Denis V. Lunev" <address@hidden> wrote:

> On 12/14/2015 06:05 PM, Igor Mammedov wrote:
> > On Mon, 14 Dec 2015 11:22:39 +0300
> > "Denis V. Lunev" <address@hidden> wrote:
> >
> >> From: Roman Kagan <address@hidden>
> >>
> >> On x86-based systems Linux determines the presence and the type of
> >> floppy drives via a query of a CMOS field.  So does SeaBIOS when
> >> populating the return data for int 0x13 function 0x08.
> >>
> >> Windows doesn't; instead, it requests this information from BIOS
> >> via int 0x13/0x08 or through ACPI objects _FDE (Floppy Drive
> >> Enumerate) and _FDI (Floppy Drive Information).  On UEFI systems
> >> only ACPI-based detection is supported.
> >>
> >> QEMU used not to provide those objects in its DSDT; as a result
> >> floppy drives were invisible to Windows on UEFI/OVMF.
> >>
> >> This patch implements those objects in ASL, making the ACPI
> >> interpreter query the CMOS field and populate the objects.  The
> >> data values used for _FDI (which, per ACPI spec, is supposed to be
> >> equivalent to BIOS int 0x13/0x08) are taken from SeaBIOS.
> > We are in process of removing static DSDT (ASL template) and
> > replacing it with dynamically generated one.
> > So please do not add new ASL to it, instead of it
> > please redo patch using AML API and it would be better if you
> > do it on top of following series:
> >   "[PATCH 00/74] pc: acpi: convert DSDT to AML API and drop ASL
> > templates support"
> >   http://qemu.patchew.org/series/address@hidden
> >
> > to avoid touching ASL code and avoid conflicts with API changes
> > Patch also could be simpler if you generate _FDE,_FDI
> > dynamically instead of trying to detect drive presence
> > from guest side.
> > See below for comments.
> Igor,
> 
> do you have any GIT tree we could be based on :) ?
> 
> Den

On Thu, 10 Dec 2015 17:44:30 +0100
Igor Mammedov <address@hidden> wrote:

> forgot to mention
> git tree for testing is available at:
> 
> address@hidden:imammedo/qemu.git drop_ASL_support_v1
> or
> https://github.com/imammedo/qemu/commits/drop_ASL_support_v1
> 
> and fixed-up series with fixed comments is at:
> 
> address@hidden:imammedo/qemu.git drop_ASL_support_wip
> or
> https://github.com/imammedo/qemu/commits/drop_ASL_support_wip

if you have in mind 2.5 stable tree for the patch then it would be
better to put stuff in SSDT, that way it could be used for stable and
later in 2.6 I could clean it up, when merging DSDT with SSDT.
Just make sure to put it in some place that avoids conflicts with above
series.
That way you won't depend on huge ACPI refactoring.