Move parsing of ACPI tables into table structures

Move mapping ACPI table memory into common location

src/hulk/acpi.d

@@ -18,7 +18,7 @@ struct Acpi
     enum uint MCFG_SIGNATURE = signature("MCFG");
     enum uint XSDT_SIGNATURE = signature("XSDT");
 
-    static align(4) struct XsdtHeader
+    static align(4) struct Header
     {
         uint signature;
         uint length;
@@ -31,35 +31,47 @@ struct Acpi
         uint creator_revision;
     }
 
-    static struct Xsdt
+    static struct XSDT
     {
-        XsdtHeader header;
+        Header header;
         /* Table pointers are not ulong-aligned! They begin at offset 36. */
         align(4) ulong[1] tables;
     }
 
-    static struct MadtHeader
+    static struct MADT
     {
-        uint signature;
-        uint length;
-        ubyte revision;
-        ubyte checksum;
-        char[6] oemid;
-        ulong oemtableid;
-        uint oem_revision;
-        uint creator_id;
-        uint creator_revision;
+        static struct Entry
+        {
+            enum LOCAL_APIC_ADDRESS_OVERRIDE = 5;
+
+            ubyte type;
+            ubyte length;
+        }
+
+        Header header;
         uint local_apic_address;
         uint flags;
+
+        void initialize()
+        {
+            apic_address = local_apic_address;
+            Klog.writefln("Found 32-bit APIC address: 0x%x", apic_address);
+            const(void) * end = cast(const(void) *)(&this) + header.length;
+            const(Entry) * entry = cast(const(Entry) *)(cast(ulong)&this + MADT.sizeof);
+            while (entry < end)
+            {
+                entry = cast(const(Entry) *)(cast(size_t)entry + entry.length);
+                if (entry.type == Entry.LOCAL_APIC_ADDRESS_OVERRIDE)
+                {
+                    /* Found a 64-bit Local APIC Address Override entry. */
+                    Klog.writefln("Found 64-bit APIC address: 0x%x", apic_address);
+                    memcpy(cast(void *)&apic_address, cast(const(void) *)entry + 4u, apic_address.sizeof);
+                }
+            }
+        }
     }
 
-    static struct MadtEntry
-    {
-        ubyte type;
-        ubyte length;
-    }
-
-    static struct MCFGTable
+    static struct MCFG
     {
         /* PCI Segment Group Memory Area Descriptor. */
         static struct SGMADesc
@@ -78,17 +90,25 @@ struct Acpi
         static assert(SGMADesc.sizeof == 16);
         static assert(SGMADesc.alignof == 4);
 
-        uint signature;
-        uint length;
-        ubyte revision;
-        ubyte checksum;
-        char[6] oemid;
-        ulong oemtableid;
-        uint oem_revision;
-        uint creator_id;
-        uint creator_revision;
+        Header header;
         uint[2] _reserved;
         SGMADesc[0] sgma_descs;
+
+        void initialize()
+        {
+            Klog.writefln("MCFG length = %u", header.length);
+            size_t n_sgma_descs = (header.length - MCFG.sgma_descs.offsetof) / MCFG.SGMADesc.sizeof;
+            Klog.writefln("# SGMA descriptors = %u", (header.length - MCFG.sgma_descs.offsetof) / MCFG.SGMADesc.sizeof);
+            for (size_t i = 0; i < n_sgma_descs; i++)
+            {
+                Klog.writefln("SGMA %u: SG %u; Bus %u-%u; addr %p",
+                        i,
+                        sgma_descs[i].pci_segment_group_number,
+                        sgma_descs[i].start_pci_bus_number,
+                        sgma_descs[i].end_pci_bus_number,
+                        sgma_descs[i].base_address);
+            }
+        }
     }
 
     public static __gshared ulong apic_address;
@@ -96,21 +116,30 @@ struct Acpi
     public static void initialize(ulong acpi_xsdt_phys)
     {
         /* Map the XSDT header. */
-        Hurl.identity_map_range(acpi_xsdt_phys, Xsdt.sizeof, 0u);
-        const(Xsdt) * xsdt = cast(const(Xsdt) *)acpi_xsdt_phys;
+        Hurl.identity_map_range(acpi_xsdt_phys, PAGE_SIZE, 0u);
+        const(XSDT) * xsdt = cast(const(XSDT) *)acpi_xsdt_phys;
         if (xsdt.header.signature != XSDT_SIGNATURE)
         {
             Klog.writef("XSDT signature invalid\n");
             return;
         }
         /* Map the entire XSDT. */
-        Hurl.identity_map_range(acpi_xsdt_phys, xsdt.header.length, 0u);
+        if (xsdt.header.length > PAGE_SIZE)
+        {
+            Hurl.identity_map_range(acpi_xsdt_phys, xsdt.header.length, 0u);
+        }
         size_t n_entries = (xsdt.header.length - xsdt.header.sizeof) / xsdt.tables[0].sizeof;
         for (size_t i = 0u; i < n_entries; i++)
         {
             ulong address = xsdt.tables[i];
-            Hurl.identity_map_range(address, 4u, 0u);
-            uint signature = *cast(const(uint) *)address;
+            Hurl.identity_map_range(address, PAGE_SIZE, 0u);
+            const(Header) * header = cast(const(Header) *)address;
+            uint length = header.length;
+            if (length > PAGE_SIZE)
+            {
+                Hurl.identity_map_range(address, length, 0u);
+            }
+            uint signature = header.signature;
             Klog.writefln("Found ACPI table %08x (%c%c%c%c)",
                     signature,
                     signature & 0xFFu,
@@ -119,49 +148,12 @@ struct Acpi
                     (signature >> 24u) & 0xFFu);
             if (signature == APIC_SIGNATURE)
             {
-                parse_apic_table(address);
+                (cast(MADT *)address).initialize();
             }
             else if (signature == MCFG_SIGNATURE)
             {
-                parse_mcfg_table(address);
+                (cast(MCFG *)address).initialize();
             }
         }
     }
-
-    private static parse_apic_table(ulong address)
-    {
-        const(MadtHeader) * madt_header = cast(const(MadtHeader) *)address;
-        Hurl.identity_map_range(address, madt_header.length, 0u);
-        apic_address = madt_header.local_apic_address;
-        Klog.writefln("Found 32-bit APIC address: 0x%x", apic_address);
-        const(void) * madt_end = cast(const(void) *)(address + madt_header.length);
-        const(MadtEntry) * madt_entry = cast(const(MadtEntry) *)(address + 0x2Cu);
-        while (madt_entry < madt_end)
-        {
-            madt_entry = cast(const(MadtEntry) *)(cast(size_t)madt_entry + madt_entry.length);
-            if (madt_entry.type == 5u)
-            {
-                /* Found a 64-bit Local APIC Address Override entry. */
-                Klog.writefln("Found 64-bit APIC address: 0x%x", apic_address);
-                memcpy(cast(void *)&apic_address, cast(const(void) *)madt_entry + 4u, 8u);
-            }
-        }
-    }
-
-    private static parse_mcfg_table(ulong address)
-    {
-        const(MCFGTable) * mcfg_table = cast(const(MCFGTable) *)address;
-        Hurl.identity_map_range(address, mcfg_table.length, 0u);
-        Klog.writefln("MCFG length = %u", mcfg_table.length);
-        size_t n_sgma_descs = (mcfg_table.length - MCFGTable.sgma_descs.offsetof) / MCFGTable.SGMADesc.sizeof;
-        Klog.writefln("# SGMA descriptors = %u", (mcfg_table.length - MCFGTable.sgma_descs.offsetof) / MCFGTable.SGMADesc.sizeof);
-        for (size_t i = 0; i < n_sgma_descs; i++)
-        {
-            Klog.writefln("SGMA %u: SG %u; Bus %u-%u; addr %p",
-                    i, mcfg_table.sgma_descs[i].pci_segment_group_number,
-                    mcfg_table.sgma_descs[i].start_pci_bus_number,
-                    mcfg_table.sgma_descs[i].end_pci_bus_number,
-                    mcfg_table.sgma_descs[i].base_address);
-        }
-    }
 }