Re: [Qemu-devel] [PATCH v2 58/74] pc: acpi: piix4: move PCI0._PRT() into SSDT

[Michael S. Tsirkin]

On Thu, Dec 10, 2015 at 05:17:07PM +0100, Igor Mammedov wrote:
> Signed-off-by: Igor Mammedov <address@hidden>
> ---
> v2:
>  - adapt build_prt() for using for PCI0._PRT(), reduces code duplication,
>    Suggested-by: Marcel Apfelbaum <address@hidden>
> 
> pc: acpi: piix4: adapt build_prt() for using for PCI0._PRT()
> 
> Signed-off-by: Igor Mammedov <address@hidden>
> ---
>  hw/i386/acpi-build.c  | 41 +++++++++++++++++++++++++++--------
>  hw/i386/acpi-dsdt.dsl | 60 
> ---------------------------------------------------
>  2 files changed, 32 insertions(+), 69 deletions(-)
> 
> diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
> index cf98037..1b065df 100644
> --- a/hw/i386/acpi-build.c
> +++ b/hw/i386/acpi-build.c
> @@ -620,6 +620,17 @@ static void build_append_pci_bus_devices(Aml 
> *parent_scope, PCIBus *bus,
>      qobject_decref(bsel);
>  }
>  
> +static Aml *build_prt_entry(const char *link_name)
> +{
> +    Aml *a_zero = aml_int(0);
> +    Aml *pkg = aml_package(4);
> +    aml_append(pkg, a_zero);
> +    aml_append(pkg, a_zero);
> +    aml_append(pkg, aml_name("%s", link_name));
> +    aml_append(pkg, a_zero);
> +    return pkg;
> +}
> +
>  /*
>   * initialize_route - Initialize the interrupt routing rule
>   * through a specific LINK:
> @@ -630,12 +641,8 @@ static Aml *initialize_route(Aml *route, const char 
> *link_name,
>                               Aml *lnk_idx, int idx)
>  {
>      Aml *if_ctx = aml_if(aml_equal(lnk_idx, aml_int(idx)));
> -    Aml *pkg = aml_package(4);
> +    Aml *pkg = build_prt_entry(link_name);
>  
> -    aml_append(pkg, aml_int(0));
> -    aml_append(pkg, aml_int(0));
> -    aml_append(pkg, aml_name("%s", link_name));
> -    aml_append(pkg, aml_int(0));
>      aml_append(if_ctx, aml_store(pkg, route));
>  
>      return if_ctx;
> @@ -651,9 +658,9 @@ static Aml *initialize_route(Aml *route, const char 
> *link_name,
>   * The hash function is  (slot + pin) & 3 -> "LNK[D|A|B|C]".
>   *
>   */
> -static Aml *build_prt(void)
> +static Aml *build_prt(bool is_pci0_prt)
>  {
> -    Aml *method, *while_ctx, *pin, *res;
> +    Aml *method, *while_ctx, *pin, *res, *if_ctx, *if_ctx2, *else_ctx2;

Move if_ctx2/if_ctx/else_ctx2 where they are used?
Also, can't we come up with better name than if_ctx2?
How about if_lnk_1 and if_pin_4?

>  
>      method = aml_method("_PRT", 0, AML_NOTSERIALIZED);
>      res = aml_local(0);
> @@ -678,7 +685,19 @@ static Aml *build_prt(void)
>  
>          /* route[2] = "LNK[D|A|B|C]", selection based on pin % 3  */
>          aml_append(while_ctx, initialize_route(route, "LNKD", lnk_idx, 0));
> -        aml_append(while_ctx, initialize_route(route, "LNKA", lnk_idx, 1));
> +        if (is_pci0_prt) {
> +            if_ctx = aml_if(aml_equal(lnk_idx, aml_int(1)));
> +            /* device 1 is the power-management device, needs SCI */

Doesn't this context belong above the previous line?

> +            if_ctx2 = aml_if(aml_equal(pin, aml_int(4)));
> +            aml_append(if_ctx2, aml_store(build_prt_entry("LNKS"), route));
> +            aml_append(if_ctx, if_ctx2);
> +            else_ctx2 = aml_else();
> +            aml_append(else_ctx2, aml_store(build_prt_entry("LNKA"), route));
> +            aml_append(if_ctx, else_ctx2);

This looks weird. Why isn't else_ctx2 added to if_ctx2?

> +            aml_append(while_ctx, if_ctx);
> +        } else {
> +            aml_append(while_ctx, initialize_route(route, "LNKA", lnk_idx, 
> 1));
> +        }
>          aml_append(while_ctx, initialize_route(route, "LNKB", lnk_idx, 2));
>          aml_append(while_ctx, initialize_route(route, "LNKC", lnk_idx, 3));
>  
> @@ -1348,6 +1367,10 @@ static void build_piix4_pci0_int(Aml *table)
>      Aml *method;
>      uint32_t irqs;
>      Aml *sb_scope = aml_scope("_SB");
> +    Aml *pci0_scope = aml_scope("PCI0");
> +
> +    aml_append(pci0_scope, build_prt(true));
> +    aml_append(sb_scope, pci0_scope);
>  
>      field = aml_field("PCI0.ISA.P40C", AML_BYTE_ACC, AML_NOLOCK, 
> AML_PRESERVE);
>      aml_append(field, aml_named_field("PRQ0", 8));
> @@ -1569,7 +1592,7 @@ build_ssdt(GArray *table_data, GArray *linker,
>                  aml_append(dev, aml_name_decl("_PXM", aml_int(numa_node)));
>              }
>  
> -            aml_append(dev, build_prt());
> +            aml_append(dev, build_prt(false));
>              crs = build_crs(PCI_HOST_BRIDGE(BUS(bus)->parent),
>                              io_ranges, mem_ranges);
>              aml_append(dev, aml_name_decl("_CRS", crs));
> diff --git a/hw/i386/acpi-dsdt.dsl b/hw/i386/acpi-dsdt.dsl
> index bc6bd45..5d741dd 100644
> --- a/hw/i386/acpi-dsdt.dsl
> +++ b/hw/i386/acpi-dsdt.dsl
> @@ -78,64 +78,4 @@ DefinitionBlock (
>          /* Hotplug notification method supplied by SSDT */
>          External(\_SB.PCI0.PCNT, MethodObj)
>      }
> -
> -
> -/****************************************************************
> - * PCI IRQs
> - ****************************************************************/
> -
> -    Scope(\_SB) {
> -        Scope(PCI0) {
> -            Method (_PRT, 0) {
> -                Store(Package(128) {}, Local0)
> -                Store(Zero, Local1)
> -                While(LLess(Local1, 128)) {
> -                    // slot = pin >> 2
> -                    Store(ShiftRight(Local1, 2), Local2)
> -
> -                    // lnk = (slot + pin) & 3
> -                    Store(And(Add(Local1, Local2), 3), Local3)
> -                    If (LEqual(Local3, 0)) {
> -                        Store(Package(4) { Zero, Zero, LNKD, Zero }, Local4)
> -                    }
> -                    If (LEqual(Local3, 1)) {
> -                        // device 1 is the power-management device, needs SCI
> -                        If (LEqual(Local1, 4)) {
> -                            Store(Package(4) { Zero, Zero, LNKS, Zero }, 
> Local4)
> -                        } Else {
> -                            Store(Package(4) { Zero, Zero, LNKA, Zero }, 
> Local4)
> -                        }
> -                    }
> -                    If (LEqual(Local3, 2)) {
> -                        Store(Package(4) { Zero, Zero, LNKB, Zero }, Local4)
> -                    }
> -                    If (LEqual(Local3, 3)) {
> -                        Store(Package(4) { Zero, Zero, LNKC, Zero }, Local4)
> -                    }
> -
> -                    // Complete the interrupt routing entry:
> -                    //    Package(4) { 0x[slot]FFFF, [pin], [link], 0) }
> -
> -                    Store(Or(ShiftLeft(Local2, 16), 0xFFFF), Index(Local4, 
> 0))
> -                    Store(And(Local1, 3),                    Index(Local4, 
> 1))
> -                    Store(Local4,                            Index(Local0, 
> Local1))
> -
> -                    Increment(Local1)
> -                }
> -
> -                Return(Local0)

Interesting. And where's this code? Probably in previous or follow-up patches 
...

> -            }
> -        }
> -
> -
> -        External(PRQ0, FieldUnitObj)
> -        External(PRQ1, FieldUnitObj)
> -        External(PRQ2, FieldUnitObj)
> -        External(PRQ3, FieldUnitObj)
> -        External(LNKA, DeviceObj)
> -        External(LNKB, DeviceObj)
> -        External(LNKC, DeviceObj)
> -        External(LNKD, DeviceObj)
> -        External(LNKS, DeviceObj)
> -    }
>  }
> -- 
> 1.8.3.1
>