Re: [Qemu-devel] [PATCH v2] pc: acpi: force FADT rev1 for 440fx based machine types

["Michael S. Tsirkin" <mst@redhat.com>]

On Fri, Jul 28, 2017 at 02:28:57PM +0200, Igor Mammedov wrote:
> On Wed, 26 Jul 2017 23:18:01 +0300
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > On Wed, Jul 26, 2017 at 04:09:37PM +0200, Igor Mammedov wrote:
> > > On Tue, 25 Jul 2017 16:36:06 +0300
> > > "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > >   
> > > > On Mon, Jul 24, 2017 at 03:50:20PM +0200, Igor Mammedov wrote:  
> > > > > w2k used to boot on QEMU until revision of FADT has
> > > > > been bumped to rev3
> > > > > (commit 77af8a2b hw/i386: Use Rev3 FADT (ACPI 2.0) instead of Rev1 to improve guest OS support.)
> > > > > 
> > > > > Keep PC machine at rev1 to remain compatible and Q35
> > > > > at rev3 where w2k isn't supported anyway so OSX could
> > > > > run as well.
> > > > > 
> > > > > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > > > > ---
> > > > > v2:
> > > > >    - make pc rev1 and q35 rev3.
> > > > >        "Michael S. Tsirkin" <mst@redhat.com>
> > > > > 
> > > > > PS:
> > > > > Only compile tested.
> > > > > 
> > > > > 
> > > > > CC: Programmingkid <programmingkidx@gmail.com>
> > > > > CC: Phil Dennis-Jordan <lists@philjordan.eu>
> > > > > CC: "Michael S. Tsirkin" <mst@redhat.com>
> > > > > 
> > > > > ---
> > > > >  hw/i386/acpi-build.c | 22 ++++++++++++++++++----
> > > > >  1 file changed, 18 insertions(+), 4 deletions(-)
> > > > > 
> > > > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > > > > index 6b7bade..b9c245c 100644
> > > > > --- a/hw/i386/acpi-build.c
> > > > > +++ b/hw/i386/acpi-build.c
> > > > > @@ -90,6 +90,7 @@ typedef struct AcpiMcfgInfo {
> > > > >  } AcpiMcfgInfo;
> > > > >  
> > > > >  typedef struct AcpiPmInfo {
> > > > > +    bool force_rev1_fadt;
> > > > >      bool s3_disabled;
> > > > >      bool s4_disabled;
> > > > >      bool pcihp_bridge_en;
> > > > > @@ -129,10 +130,13 @@ static void acpi_get_pm_info(AcpiPmInfo *pm)
> > > > >      Object *obj = NULL;
> > > > >      QObject *o;
> > > > >  
> > > > > +    pm->force_rev1_fadt = false;
> > > > >      pm->cpu_hp_io_base = 0;
> > > > >      pm->pcihp_io_base = 0;
> > > > >      pm->pcihp_io_len = 0;
> > > > >      if (piix) {
> > > > > +        /* w2k requires FADT(rev1) or it won't boot, keep PC compatible */
> > > > > +        pm->force_rev1_fadt = true;
> > > > >          obj = piix;
> > > > >          pm->cpu_hp_io_base = PIIX4_CPU_HOTPLUG_IO_BASE;
> > > > >          pm->pcihp_io_base =
> > > > > @@ -304,6 +308,9 @@ static void fadt_setup(AcpiFadtDescriptorRev3 *fadt, AcpiPmInfo *pm)
> > > > >          fadt->flags |= cpu_to_le32(1 << ACPI_FADT_F_FORCE_APIC_CLUSTER_MODEL);
> > > > >      }
> > > > >      fadt->century = RTC_CENTURY;
> > > > > +    if (pm->force_rev1_fadt) {
> > > > > +        return;
> > > > > +    }
> > > > >  
> > > > >      fadt->flags |= cpu_to_le32(1 << ACPI_FADT_F_RESET_REG_SUP);
> > > > >      fadt->reset_value = 0xf;
> > > > > @@ -342,6 +349,8 @@ build_fadt(GArray *table_data, BIOSLinker *linker, AcpiPmInfo *pm,
> > > > >      unsigned fw_ctrl_offset = (char *)&fadt->firmware_ctrl - table_data->data;
> > > > >      unsigned dsdt_entry_offset = (char *)&fadt->dsdt - table_data->data;
> > > > >      unsigned xdsdt_entry_offset = (char *)&fadt->x_dsdt - table_data->data;
> > > > > +    int fadt_size = sizeof(*fadt);
> > > > > +    int rev = 3;
> > > > >  
> > > > >      /* FACS address to be filled by Guest linker */
> > > > >      bios_linker_loader_add_pointer(linker,
> > > > > @@ -353,12 +362,17 @@ build_fadt(GArray *table_data, BIOSLinker *linker, AcpiPmInfo *pm,
> > > > >      bios_linker_loader_add_pointer(linker,
> > > > >          ACPI_BUILD_TABLE_FILE, dsdt_entry_offset, sizeof(fadt->dsdt),
> > > > >          ACPI_BUILD_TABLE_FILE, dsdt_tbl_offset);
> > > > > -    bios_linker_loader_add_pointer(linker,
> > > > > -        ACPI_BUILD_TABLE_FILE, xdsdt_entry_offset, sizeof(fadt->x_dsdt),
> > > > > -        ACPI_BUILD_TABLE_FILE, dsdt_tbl_offset);
> > > > > +    if (pm->force_rev1_fadt) {
> > > > > +        rev = 1;
> > > > > +        fadt_size = offsetof(typeof(*fadt), reset_register);    
> > > > 
> > > > I don't really like it that we are using structs to format fields - I
> > > > would prefer build_append_int_noprefix based APIs - but since we do,
> > > > let's add a proper structure for FADT rev 1 instead of this hack. 
>  
> Michael,
> 
> I've tried to switch FADT to build_append_int_noprefix APIs,
> but it turned out into quite a bit of re-factoring including
> clean-ups and adding new APIs to pack all the stuff in FADT.
> 
> It's too much for hard freeze, lets not rush it and go with
> this patch for 2.10 to put out fire.
> 
> When 2.11 merge window is open I'll rebase/post FADTv1/3
> conversion to build_append_int_noprefix API.

Makes sense.