Commit 0d8935e3 authored by Marcel Apfelbaum's avatar Marcel Apfelbaum Committed by Michael S. Tsirkin
Browse files

hw/apci: add _PRT method for extra PCI root busses 



Signed-off-by: default avatarMarcel Apfelbaum <marcel@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarLaszlo Ersek <lersek@redhat.com>
parent a4894206

hw/i386/acpi-build.c

+81 −0
Original line number Diff line number Diff line
@@ -617,6 +617,86 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus, 
    aml_append(parent_scope, method);

}



/*

 * initialize_route - Initialize the interrupt routing rule

 * through a specific LINK:

 *  if (lnk_idx == idx)

 *      route using link 'link_name'

 */

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_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;

}



/*

 * build_prt - Define interrupt rounting rules

 *

 * Returns an array of 128 routes, one for each device,

 * based on device location.

 * The main goal is to equaly distribute the interrupts

 * over the 4 existing ACPI links (works only for i440fx).

 * The hash function is  (slot + pin) & 3 -> "LNK[D|A|B|C]".

 *

 */

static Aml *build_prt(void)

{

    Aml *method, *while_ctx, *pin, *res;



    method = aml_method("_PRT", 0);

    res = aml_local(0);

    pin = aml_local(1);

    aml_append(method, aml_store(aml_package(128), res));

    aml_append(method, aml_store(aml_int(0), pin));



    /* while (pin < 128) */

    while_ctx = aml_while(aml_lless(pin, aml_int(128)));

    {

        Aml *slot = aml_local(2);

        Aml *lnk_idx = aml_local(3);

        Aml *route = aml_local(4);



        /* slot = pin >> 2 */

        aml_append(while_ctx,

                   aml_store(aml_shiftright(pin, aml_int(2)), slot));

        /* lnk_idx = (slot + pin) & 3 */

        aml_append(while_ctx,

                   aml_store(aml_and(aml_add(pin, slot), aml_int(3)), lnk_idx));



        /* 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));

        aml_append(while_ctx, initialize_route(route, "LNKB", lnk_idx, 2));

        aml_append(while_ctx, initialize_route(route, "LNKC", lnk_idx, 3));



        /* route[0] = 0x[slot]FFFF */

        aml_append(while_ctx,

            aml_store(aml_or(aml_shiftleft(slot, aml_int(16)), aml_int(0xFFFF)),

                      aml_index(route, aml_int(0))));

        /* route[1] = pin & 3 */

        aml_append(while_ctx,

            aml_store(aml_and(pin, aml_int(3)), aml_index(route, aml_int(1))));

        /* res[pin] = route */

        aml_append(while_ctx, aml_store(route, aml_index(res, pin)));

        /* pin++ */

        aml_append(while_ctx, aml_increment(pin));

    }

    aml_append(method, while_ctx);

    /* return res*/

    aml_append(method, aml_return(res));



    return method;

}



static void

build_ssdt(GArray *table_data, GArray *linker,

           AcpiCpuInfo *cpu, AcpiPmInfo *pm, AcpiMiscInfo *misc,
@@ -655,6 +735,7 @@ build_ssdt(GArray *table_data, GArray *linker, 
                       aml_name_decl("_UID", aml_string("PC%.02X", bus_num)));

            aml_append(dev, aml_name_decl("_HID", aml_string("PNP0A03")));

            aml_append(dev, aml_name_decl("_BBN", aml_int(bus_num)));

            aml_append(dev, build_prt());

            aml_append(scope, dev);

            aml_append(ssdt, scope);

        }