Re: [Qemu-devel] [PATCH 50/74] pc: acpi: move FDC0 device from DSDT to SSDT

[Igor Mammedov <imammedo@redhat.com>]

On Sat, 19 Dec 2015 21:44:55 +0200
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Thu, Dec 10, 2015 at 12:41:44AM +0100, Igor Mammedov wrote:
> > Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> > ---
> >  hw/i386/acpi-build.c      | 38 ++++++++++++++++++++++++++++++++------
> >  hw/i386/acpi-dsdt-isa.dsl | 18 ------------------
> >  2 files changed, 32 insertions(+), 24 deletions(-)
> > 
> > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> > index e5ec6af..2f0f2e1 100644
> > --- a/hw/i386/acpi-build.c
> > +++ b/hw/i386/acpi-build.c
> > @@ -1173,17 +1173,34 @@ static void build_hpet_aml(Aml *table)
> >  
> >  static Aml *
> >  build_eisa_device_aml(const char *name, const char *hid, Aml *crs,
> > -                      bool have_sta)
> > +                      bool have_sta, const char *present_field)
> 
> At this point, the number of arguments is getting ridiculous.
> I think you should give it up, and write a function
> per device type, even if there's a minor code duplication
> as a result.
> 
> As a bonus, we will get reasonably readable function
> names, e.g.  build_floppy_controller()
> 
> >  {
> >      Aml *dev;
> >      Aml *method;
> > -    Aml *a_device_present = aml_int(0x0f);
> >  
> >      dev = aml_device("%s", name);
> >      aml_append(dev, aml_name_decl("_HID", aml_eisaid(hid)));
> >      if (have_sta) {
> > +        Aml *if_ctx;
> > +        Aml *else_ctx;
> > +        Aml *a_zero = aml_int(0);
> > +        Aml *a_is_present = aml_local(0);
> > +        Aml *a_device_present = aml_int(0x0f);
> > +        Aml *a_device_not_present = aml_int(0x00);
> > +
> 
> What does a_ prefix mean here?
it's used to distinguish aml variables.

> 
> >          method = aml_method("_STA", 0, AML_NOTSERIALIZED);
> > -        aml_append(method, aml_return(a_device_present));
> > +        if (!present_field) {
> > +            aml_append(method, aml_return(a_device_present));
> > +        } else {
> > +            aml_append(method,
> > +                aml_store(aml_name("%s", present_field), a_is_present));
> > +            if_ctx = aml_if(aml_equal(a_is_present, a_zero));
> > +            aml_append(if_ctx, aml_return(a_device_not_present));
> > +            aml_append(method, if_ctx);
> > +            else_ctx = aml_else();
> > +            aml_append(else_ctx, aml_return(a_device_present));
> > +            aml_append(method, else_ctx);
> > +        }
> >          aml_append(dev, method);
> >      }
> >      aml_append(dev, aml_name_decl("_CRS", crs));
> > @@ -1201,19 +1218,28 @@ static void build_isa_devices_aml(Aml *table)
> >      aml_append(crs, aml_irq_no_flags(8));
> >      aml_append(crs, aml_io(AML_DECODE16, 0x0072, 0x0072, 0x02, 0x06));
> >      aml_append(scope, build_eisa_device_aml(
> > -        "RTC", "PNP0B00", crs, false));
> > +        "RTC", "PNP0B00", crs, false, NULL));
> >  
> >      crs = aml_resource_template();
> >      aml_append(crs, aml_io(AML_DECODE16, 0x0060, 0x0060, 0x01, 0x01));
> >      aml_append(crs, aml_io(AML_DECODE16, 0x0064, 0x0064, 0x01, 0x01));
> >      aml_append(crs, aml_irq_no_flags(1));
> >      aml_append(scope, build_eisa_device_aml(
> > -        "KBD", "PNP0303", crs, true));
> > +        "KBD", "PNP0303", crs, true, NULL));
> >  
> >      crs = aml_resource_template();
> >      aml_append(crs, aml_irq_no_flags(12));
> >      aml_append(scope, build_eisa_device_aml(
> > -        "MOU", "PNP0F13", crs, true));
> > +        "MOU", "PNP0F13", crs, true, NULL));
> > +
> > +    crs = aml_resource_template();
> > +    aml_append(crs, aml_io(AML_DECODE16, 0x03F2, 0x03F2, 0x00, 0x04));
> > +    aml_append(crs, aml_io(AML_DECODE16, 0x03F7, 0x03F7, 0x00, 0x01));
> > +    aml_append(crs, aml_irq_no_flags(6));
> > +    aml_append(crs,
> > +        aml_dma(AML_COMPATIBILITY, AML_NOTBUSMASTER, AML_TRANSFER8, 2));
> > +    aml_append(scope, build_eisa_device_aml(
> > +        "FDC0", "PNP0700", crs, true, "FDEN"));
> >  
> >      aml_append(table, scope);
> >  }
> > diff --git a/hw/i386/acpi-dsdt-isa.dsl b/hw/i386/acpi-dsdt-isa.dsl
> > index 8936271..64dd4ac 100644
> > --- a/hw/i386/acpi-dsdt-isa.dsl
> > +++ b/hw/i386/acpi-dsdt-isa.dsl
> > @@ -16,24 +16,6 @@
> >  /* Common legacy ISA style devices. */
> >  Scope(\_SB.PCI0.ISA) {
> >  
> > -    Device(FDC0) {
> > -        Name(_HID, EisaId("PNP0700"))
> > -        Method(_STA, 0, NotSerialized) {
> > -            Store(FDEN, Local0)
> > -            If (LEqual(Local0, 0)) {
> > -                Return (0x00)
> > -            } Else {
> > -                Return (0x0F)
> > -            }
> > -        }
> 
> All these guys have in common is the _STA method.
> So write a function generating one, and be done with it.
I'll try to do so.

> 
> 
> > -        Name(_CRS, ResourceTemplate() {
> > -            IO(Decode16, 0x03F2, 0x03F2, 0x00, 0x04)
> > -            IO(Decode16, 0x03F7, 0x03F7, 0x00, 0x01)
> > -            IRQNoFlags() { 6 }
> > -            DMA(Compatibility, NotBusMaster, Transfer8) { 2 }
> > -        })
> > -    }
> > -
> >      Device(LPT) {
> >          Name(_HID, EisaId("PNP0400"))
> >          Method(_STA, 0, NotSerialized) {
> > -- 
> > 1.8.3.1
> >