Changeset 71426 in vbox for trunk/src/VBox/Devices/PC/BIOS

Timestamp:

Mar 21, 2018 11:49:59 AM (7 years ago)

Author:

vboxsync

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

121394

Message:

BIOS: Added disabled code which can place the FDPT outside of conventional memory.

Location:

trunk/src/VBox/Devices/PC/BIOS

Files:

• ata.c (modified) (2 diffs)
• ebda.h (modified) (1 diff)
• makefile (modified) (2 diffs)

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

@@ -552 +552 @@
                     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 *));
@@ -560 +569 @@
                  * isn't worth the effort of converting from AMI to Award CMOS
                  * format. Just do it here. */
+                fdpt->resvd1 = fdpt->resvd2 = 0;
+
                 fdpt->lcyl  = lgeo.cylinders;
                 fdpt->lhead = lgeo.heads;

trunk/src/VBox/Devices/PC/BIOS/ebda.h

@@ -148 +148 @@
     uint8_t     sig;
     uint8_t     spt;
-    uint8_t     resvd1[4];
+    uint32_t    resvd1;
     uint16_t    cyl;
     uint8_t     head;
-    uint8_t     resvd2[2];
+    uint16_t    resvd2;
     uint8_t     lspt;
     uint8_t     csum;

trunk/src/VBox/Devices/PC/BIOS/makefile

@@ -19 +19 @@
 CFLAGS   = -q -0 -wx -zu -s -oas -d1+ -ms
 CFLAGS32 = -q -wx -zu -s -oas -d1+ -ms -nt=BIOS32 -nd=BIOS32
+# -oat seems to prevent ENTER/LEAVE generation
+#CFLAGS32 = -q -wx -zu -s -oat -d1+ -ms -nt=BIOS32 -nd=BIOS32
 
 DEFS = -DVBOX -DVBOX_LANBOOT_SEG=0xE200 -DVBOX_VERSION_STRING=$(Q)0.9$(Q) &
@@ -53 +55 @@
          clname DATA segaddr=0xF000 segment _DATA &
          clname CODE &
-         segment _TEXT segaddr=0xF000 offset=0x1600 &
+         segment _TEXT segaddr=0xF000 offset=0x1C00 &
          segment BIOS32 segaddr=0xF000 offset=0xDB00 &
          segment BIOSSEG segaddr=0xF000 offset=0xE000 &