Changeset 104067 in vbox for trunk

Timestamp:

Mar 26, 2024 4:35:54 PM (12 months ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

162460

Message:

Comments.

File:

• trunk/src/VBox/Devices/PC/BIOS/ata.c (modified) (3 diffs)

trunk/src/VBox/Devices/PC/BIOS/ata.c

@@ -628 +628 @@
                     fdpt = ebda_seg :> &EbdaData->fdpt1;
 
-#if 0
-                /* Place the FDPT outside of conventional memory. Needed for
-                 * 286 XENIX 2.1.3/2.2.1 because it completely wipes out
-                 * the EBDA and low memory. Hack!
-                 */
-                fdpt = MK_FP(0xE200, 0xf00);
-                fdpt += device;
-#endif
-
                 /* Set the INT 41h or 46h pointer. */
                 int_vec  = MK_FP(0, (0x41 + device * 5) * sizeof(void __far *));
@@ -664 +655 @@
                  * INT 41h/46h at the drive table in ROM.
                  * This is required for some old guests which look at INT 41h/46h,
-                 * but either insist that it point to a high segment (NetWare 2.x)
+                 * but either insist that it points well above 640K (NetWare 2.x)
                  * or wipe out all RAM (286 XENIX 2.1.3/2.2.1).
+                 *
+                 * NB: Writing into the F000 segment and storing the FDPT there
+                 * would also solve some of these problems.
                  */
                 i   = inb_cmos(0x12);
@@ -673 +667 @@
                     i = inb_cmos(0x19 + device);
 
-                if (i <= 23) {  // Should be in sync with DevPcBios.cpp
+                if (i <= 23) {  // Should be in sync with DevPcBios.cpp and orgs.asm
                     fdpt = MK_FP(0xF000, 0xE401);
                     fdpt += i - 1;