Move MCFG ACPI table processing from ACPI to PCI

src/hulk/pci.d

@@ -29,6 +29,38 @@ struct Pci
     /** XHCI controller device type. */
     enum XHCI_CONTROLLER = Type(0x0Cu, 0x03u, 0x30u);
 
+    /**
+     * MCFG ACPI table structure.
+     */
+    static struct MCFG
+    {
+        /* PCI Segment Group Memory Area Descriptor. */
+        static struct SGMADesc
+        {
+            uint[2] base_address_a;
+            ushort pci_segment_group_number;
+            ubyte start_pci_bus_number;
+            ubyte end_pci_bus_number;
+            uint _reserved;
+
+            public @property ulong base_address() const
+            {
+                return base_address_a[0] | (cast(ulong)base_address_a[1] << 32);
+            }
+        }
+        static assert(SGMADesc.sizeof == 16);
+        static assert(SGMADesc.alignof == 4);
+
+        Acpi.Header header;
+        uint[2] _reserved;
+        SGMADesc[0] sgma_descs;
+
+        size_t n_sgma_descs()
+        {
+            return (header.length - MCFG.sgma_descs.offsetof) / MCFG.SGMADesc.sizeof;
+        }
+    }
+
     /**
      * PCI device address (bus number, device number, function number).
      */
@@ -385,11 +417,12 @@ struct Pci
 
     public static void initialize()
     {
-        Klog.writefln("\a3Initializing PCI Bus");
-        size_t n_sgma_descs = Acpi.mcfg.n_sgma_descs;
+        Klog.writefln("\a3Initializing PCI");
+        MCFG * mcfg = cast(MCFG *)Acpi.get_table("MCFG");
+        size_t n_sgma_descs = mcfg.n_sgma_descs;
         for (size_t i = 0u; i < n_sgma_descs; i++)
         {
-            Acpi.MCFG.SGMADesc * sgma_desc = &Acpi.mcfg.sgma_descs[i];
+            MCFG.SGMADesc * sgma_desc = &mcfg.sgma_descs[i];
             ulong base_address = sgma_desc.base_address;
             uint start_pci_bus = sgma_desc.start_pci_bus_number;
             uint end_pci_bus = sgma_desc.end_pci_bus_number;