[Qemu-devel] [PATCH v4 for-2.3 11/25] hw/apci: add _PRT method for extra PCI root busses

[Marcel Apfelbaum <marcel@redhat.com>]

Signed-off-by: Marcel Apfelbaum <marcel@redhat.com>
---
 hw/i386/acpi-build.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 65 insertions(+)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index e5709e8..e7a1a36 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -664,6 +664,70 @@ static void build_append_pci_bus_devices(Aml *parent_scope, PCIBus *bus,
     aml_append(parent_scope, method);
 }
 
+static Aml *build_link(Aml *lnk, Aml *lnk_pkg, const char *link_name, int idx)
+{
+    Aml *if_ctx, *pkg;
+
+    if_ctx = aml_if(aml_equal(lnk, aml_int(idx)));
+    pkg = aml_package(4);
+    aml_append(pkg, aml_int(0));
+    aml_append(pkg, aml_int(0));
+    aml_append(pkg, aml_name(link_name, ""));
+    aml_append(pkg, aml_int(0));
+    aml_append(if_ctx, aml_store(pkg, lnk_pkg));
+
+    return if_ctx;
+}
+
+static Aml *build_prt(void)
+{
+    Aml *method, *while_ctx, *pin, *slot, *lnk, *pkg, *res;
+
+    method = aml_method("_PRT", 0);
+    res = aml_local(0);
+    pin = aml_local(1);
+    slot = aml_local(2);
+    lnk = aml_local(3);
+    pkg = aml_local(4);
+
+    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)));
+    {
+        /* slot = pin >> 2 */
+        aml_append(while_ctx,
+                   aml_store(aml_shiftright(pin, aml_int(2)), slot));
+        /* lnk = (slot + pin) & 3 */
+        aml_append(while_ctx,
+                   aml_store(aml_and(aml_add(pin, slot), aml_int(3)), lnk));
+
+        /* pkg[2] = "LNK[A|B|C|D]", selection based on lnk % 3  */
+        aml_append(while_ctx, build_link(lnk, pkg, "LNKD", 0));
+        aml_append(while_ctx, build_link(lnk, pkg, "LNKA", 1));
+        aml_append(while_ctx, build_link(lnk, pkg, "LNKB", 2));
+        aml_append(while_ctx, build_link(lnk, pkg, "LNKC", 3));
+
+        /* pkg[0] = 0x[slot]FFFF */
+        aml_append(while_ctx,
+            aml_store(aml_or(aml_shiftleft(slot, aml_int(16)), aml_int(0xFFFF)),
+                      aml_index(pkg, aml_int(0))));
+        /* pkg[1] = pin & 3 */
+        aml_append(while_ctx,
+            aml_store(aml_and(pin, aml_int(3)), aml_index(pkg, aml_int(1))));
+        /* res[pin] = pkg */
+        aml_append(while_ctx, aml_store(pkg, 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,
@@ -708,6 +772,7 @@ build_ssdt(GArray *table_data, GArray *linker,
             aml_append(dev, aml_name_decl("_HID", aml_string("PNP0A03")));
             aml_append(dev,
                 aml_name_decl("_BBN", aml_int((uint8_t)bus_info->bus)));
+            aml_append(dev, build_prt());
             aml_append(scope, dev);
             aml_append(ssdt, scope);
         }
-- 
2.1.0