Changeset 59114 in vbox for trunk/src/VBox

Timestamp:

Dec 14, 2015 1:46:52 PM (9 years ago)

Author:

vboxsync

Message:

BIOS: Merged RMW sequences into single instructions.

Location:

trunk/src/VBox/Devices/PC/BIOS

Files:

• floppy.c (modified) (3 diffs)
• keyboard.c (modified) (4 diffs)
• makefile (modified) (2 diffs)
• orgs.asm (modified) (2 diffs)

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

@@ -82 +82 @@
 uint8_t floppy_wait_for_interrupt(void)
 {
+    uint32_t    retries = 18;
+
     int_disable();
-    for (;;)
+    for (;retries;--retries)
     {
         uint8_t val8 = read_byte(0x0040, 0x003e);
@@ -90 +92 @@
         int_enable_hlt_disable();
     }
+    return 0;
 }
 
@@ -175 +178 @@
         // wait on 40:3e bit 7 to become 1
         do {
+            val8 = inb(0x80);
             val8 = read_byte(0x0040, 0x003e);
-        } while ( (val8 & 0x80) == 0 );
+        } while ( (val8 & 0x80) == 0 && --retries);
         val8 &= 0x7f;
         int_disable();

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

@@ -55 +55 @@
 void jmp_post(void);
 #pragma aux jmp_post = "jmp far ptr post" aborts;
+
+extern void eoi_master_pic(void);    /* in assembly code */
+#pragma aux eoi_master_pic "*";
+
+/* Manually save/restore BP around invoking user Ctrl-Break handler.
+ * The handler could conceivably clobber BP and the compiler does not
+ * believe us when we say 'modify [bp]' (BP is considered unalterable).
+ */
+void int_1b(void);
+#pragma aux int_1b =    \
+    "push bp"           \
+    "int 1Bh"           \
+    "pop bp"            \
+    value [bp] modify [bp];
+
 
 #define none 0
@@ -358 +373 @@
     }
 
-
-    shift_flags = read_byte(0x0040, 0x17);
     mf2_flags = read_byte(0x0040, 0x18);
     mf2_state = read_byte(0x0040, 0x96);
+    /* Check if suspend flag set but no E1 prefix (i.e. not Pause). */
+    if ((mf2_flags & 0x08) && !(shift_flags & 0x01)) {
+        /* Pause had been pressed. Clear suspend flag and do nothing. */
+        mf2_flags &= ~0x08;
+        write_byte(0x0040, 0x18, mf2_flags);
+        return;
+    }
+
+    shift_flags = read_byte(0x0040, 0x17);
     asciicode = 0;
 
@@ -441 +463 @@
         break;
 
-    case 0x45: /* Num Lock press */
+    case 0x45: /* Num Lock/Pause press */
         if ((mf2_state & 0x03) == 0) {
+            /* Num Lock */
             mf2_flags |= 0x20;
             write_byte(0x0040, 0x18, mf2_flags);
             shift_flags ^= 0x20;
             write_byte(0x0040, 0x17, shift_flags);
-        }
-        break;
-    case 0xc5: /* Num Lock release */
+        } else {
+            /* Pause */
+            mf2_flags |= 0x08;  /* Set the suspend flag */
+            write_byte(0x0040, 0x18, mf2_flags);
+
+            /* Enable keyboard and send EOI. */
+            outp(0x64, 0xae);
+            eoi_master_pic();
+
+            while (read_byte(0x0040, 0x18) & 0x08)
+                ;   /* Hold on and wait... */
+
+            //@todo: We will send EOI again (and enable keyboard) on the way out; we shouldn't
+        }
+        break;
+    case 0xc5: /* Num Lock/Pause release */
         if ((mf2_state & 0x03) == 0) {
             mf2_flags &= ~0x20;
@@ -456 +492 @@
         break;
 
-    case 0x46: /* Scroll Lock press */
-        mf2_flags |= 0x10;
-        write_byte(0x0040, 0x18, mf2_flags);
-        shift_flags ^= 0x10;
-        write_byte(0x0040, 0x17, shift_flags);
-        break;
-
-    case 0xc6: /* Scroll Lock release */
-        mf2_flags &= ~0x10;
-        write_byte(0x0040, 0x18, mf2_flags);
+    case 0x46: /* Scroll Lock/Break press */
+        if (mf2_state & 0x02) { /* E0 prefix? */
+            /* Zap the keyboard buffer. */
+            write_word(0x0040, 0x001c, read_word(0x0040, 0x001a));
+
+            write_byte(0x0040, 0x71, 0x80); /* Set break flag */
+            outp(0x64, 0xae);               /* Enable keyboard */
+            int_1b();                       /* Invoke user handler */
+            enqueue_key(0, 0);              /* Dummy key press*/
+        } else {
+            mf2_flags |= 0x10;
+            write_byte(0x0040, 0x18, mf2_flags);
+            shift_flags ^= 0x10;
+            write_byte(0x0040, 0x17, shift_flags);
+        }
+        break;
+
+    case 0xc6: /* Scroll Lock/Break release */
+        if (!(mf2_state & 0x02)) {  /* Only if no E0 prefix */
+            mf2_flags &= ~0x10;
+            write_byte(0x0040, 0x18, mf2_flags);
+        }
         break;
 

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

@@ -16 +16 @@
 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) &
@@ -45 +47 @@
          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 &

trunk/src/VBox/Devices/PC/BIOS/orgs.asm

@@ -908 +908 @@
                 xor     ax, ax
                 mov     ds, ax
-                mov     al, ds:[496h]   ; mf2_state |= 0x02
-                or      al, 2           ; TODO: why not RMW?
-                mov     ds:[496h], al
+                or      byte ptr ds:[496h], 2   ; mf2_state |= 0x02
                 jmp     int09_done
 
@@ -917 +915 @@
                 jne     int09_process_key
                 xor     ax, ax
-                mov     ds, ax          ; TODO: haven't we just done that??
-                mov     al, ds:[496h]
-                or      al, 1
-                mov     ds:[496h], al   ; TODO: why not RMW?
+                mov     ds, ax
+                or      byte ptr ds:[496h], 1   ; mf2_state | 0x01
                 jmp     int09_done