Changeset 24244

Timestamp:

03/05/08 15:06:18 (9 months ago)

Author:

korli

Message:

here with 3GB of memory, a 4GB MTRR slot is being written, which triggers a reboot.
we now split more than 2GB MTRR slot, we might improve this and split more and more.
this could fix the bug #1711.

Files:

• haiku/trunk/src/system/kernel/arch/x86/arch_vm.cpp (modified) (4 diffs)

haiku/trunk/src/system/kernel/arch/x86/arch_vm.cpp

@@ -92 +92 @@
                 return B_OK;
 
+        uint32 newType;
+
         switch (type) {
                 case B_MTR_UC:
-                        type = IA32_MTR_UNCACHED;
+                        newType = IA32_MTR_UNCACHED;
                         break;
                 case B_MTR_WC:
-                        type = IA32_MTR_WRITE_COMBINING;
+                        newType = IA32_MTR_WRITE_COMBINING;
                         break;
                 case B_MTR_WT:
-                        type = IA32_MTR_WRITE_THROUGH;
+                        newType = IA32_MTR_WRITE_THROUGH;
                         break;
                 case B_MTR_WP:
-                        type = IA32_MTR_WRITE_PROTECTED;
+                        newType = IA32_MTR_WRITE_PROTECTED;
                         break;
                 case B_MTR_WB:
-                        type = IA32_MTR_WRITE_BACK;
+                        newType = IA32_MTR_WRITE_BACK;
                         break;
 
@@ -117 +119 @@
 
         // length must be a power of 2; just round it up to the next value
-        length = nearest_power(length);
-        if (length + base <= base) {
+        uint64 newLength = nearest_power(length);
+
+        // avoids more than 2GB slots
+        if (newLength > 0x80000000)
+                newLength = 0x80000000;
+
+        if (newLength + base <= base) {
                 // 4GB overflow
                 return B_BAD_VALUE;
@@ -124 +131 @@
 
         // base must be aligned to the length
-        if (base & (length - 1))
+        if (base & (newLength - 1))
                 return B_BAD_VALUE;
 
@@ -132 +139 @@
 
         TRACE(("allocate MTRR slot %ld, base = %Lx, length = %Lx\n", index,
-                base, length));
+                base, newLength));
 
         sMemoryTypeIDs[index] = id;
-        x86_set_mtrr(index, base, length, type);
+        x86_set_mtrr(index, base, newLength, newType);
+
+        // now handle remaining memory
+        if (length > newLength) {
+                // TODO iterate over smaller lengths to avoid the PCI hole after the physical memory.
+                set_memory_type(id, base + newLength, length - newLength, type);
+        }
 
         return B_OK;