Changeset 17597 in vbox

Timestamp:

Mar 9, 2009 5:39:05 PM (16 years ago)

Author:

vboxsync

Message:

DevPcBios,DevACPI: Use 0xffe00000 as the max low ram limit in both places (or the the guest won't find the ACPI tables).

Location:

trunk/src/VBox/Devices/PC

Files:

• DevACPI.cpp (modified) (1 diff)
• DevPcBios.cpp (modified) (1 diff)

trunk/src/VBox/Devices/PC/DevACPI.cpp

@@ -1765 +1765 @@
     if (cbRamLow > UINT32_C(0xffe00000)) /* See MEM3. */
     {
-        /** @todo Do this in the E820 table/CMOS as well or things won't work right. */
+        /* Note: This is also enforced by DevPcBios.cpp. */
         LogRel(("DevACPI: Clipping cbRamLow=%#RX64 down to 0xffe00000.\n", cbRamLow));
         cbRamLow = UINT32_C(0xffe00000);

trunk/src/VBox/Devices/PC/DevPcBios.cpp

@@ -539 +539 @@
 
     /* Bochs BIOS specific? Anyway, it's the amount of memory above 16MB
-       and below 4GB (as it can only hold 4GB+16M). For 0E820h to work right,
-       this has to indicate less than 0xfffc0000 bytes or it'll conflict with
-       the high BIOS area. */
+       and below 4GB (as it can only hold 4GB+16M). We have to chop off the
+       top 2MB or it conflict with what the ACPI tables return. (Should these
+       be adjusted, we still have to chop it at 0xfffc0000 or it'll conflict
+       with the high BIOS mapping.) */
     uint64_t const offRamHole = _4G - pThis->cbRamHole;
     if (pThis->cbRam > 16 * _1M)
-    {
-        u32 = (uint32_t)( (RT_MIN(pThis->cbRam, offRamHole) - 16 * _1M) / _64K );
-        u32 = RT_MIN(u32, 0xfefc);
-    }
+        u32 = (uint32_t)( (RT_MIN(RT_MIN(pThis->cbRam, offRamHole), UINT32_C(0xffe00000)) - 16U * _1M) / _64K );
     else
         u32 = 0;