diff --git a/src/hulk/cpu.d b/src/hulk/cpu.d
index e4d81dd..827d2c2 100644
--- a/src/hulk/cpu.d
+++ b/src/hulk/cpu.d
@@ -221,9 +221,9 @@ ushort in16(ushort ioaddr)
     return __asm!ushort("inw %dx, %ax", "={ax},{dx}", ioaddr);
 }
 
-ulong in32(ushort ioaddr)
+uint in32(ushort ioaddr)
 {
-    return __asm!ulong("inl %dx, %eax", "={eax},{dx}", ioaddr);
+    return __asm!uint("inl %dx, %eax", "={eax},{dx}", ioaddr);
 }
 
 void out8(ushort ioaddr, ubyte v)
@@ -236,7 +236,7 @@ void out16(ushort ioaddr, ushort v)
     __asm("outw %ax, %dx", "{dx},{ax}", ioaddr, v);
 }
 
-void out32(ushort ioaddr, ulong v)
+void out32(ushort ioaddr, uint v)
 {
     __asm("outl %eax, %dx", "{dx},{eax}", ioaddr, v);
 }
diff --git a/src/hulk/pci.d b/src/hulk/pci.d
index eff3b28..754bf28 100644
--- a/src/hulk/pci.d
+++ b/src/hulk/pci.d
@@ -26,9 +26,9 @@ struct Pci
         }
     }
 
-    private static ulong read_config_register(ulong bus_id, ulong device_idx, ulong register_id)
+    private static uint read_config_register(uint bus_id, uint device_idx, uint register_id)
     {
-        ulong addr = 0x8000_0000u | (bus_id << 16u) | (device_idx << 11u) | (register_id << 2u);
+        uint addr = 0x8000_0000u | (bus_id << 16u) | (device_idx << 11u) | (register_id << 2u);
         out32(IO_ADDR_CONFIG_ADDRESS, addr);
         return in32(IO_ADDR_CONFIG_DATA);
     }
@@ -59,12 +59,12 @@ struct Pci
         }
     }
 
-    private static void scan(ulong bus_id, ulong device_idx)
+    private static void scan(uint bus_id, uint device_idx)
     {
         ulong reg0 = read_config_register(bus_id, device_idx, 0u);
         if (reg0 != 0xFFFFFFFFu)
         {
-            ulong reg2 = read_config_register(bus_id, device_idx, 2u);
+            uint reg2 = read_config_register(bus_id, device_idx, 2u);
             ushort vendor_id = reg0 & 0xFFFFu;
             ushort device_id = (reg0 >> 16u) & 0xFFFFu;
             ubyte class_id = (reg2 >> 24u) & 0xFFu;
@@ -81,9 +81,9 @@ struct Pci
     public static void initialize()
     {
         Klog.writefln("Scanning PCI devices...");
-        for (ulong bus_id = 0u; bus_id < 256u; bus_id++)
+        for (uint bus_id = 0u; bus_id < 256u; bus_id++)
         {
-            for (ulong device_idx = 0u; device_idx < 32u; device_idx++)
+            for (uint device_idx = 0u; device_idx < 32u; device_idx++)
             {
                 scan(bus_id, device_idx);
             }