Changeset 189 for soft/giet_vm/sys/switch.s

Timestamp:

Aug 7, 2012, 6:37:49 PM (12 years ago)

Author:

alain

Message:

Introducing a new release where all initialisation
is done in the boot code.

File:

• soft/giet_vm/sys/switch.s (modified) (4 diffs)

soft/giet_vm/sys/switch.s

@@ -1 +1 @@
 /******************************************************************************
-* This function receives two arguments representing addresses of task
-* contexts, respectively for the current running task to be descheduled and
-* for the next task to be scheduled.
+* This function receives two arguments that are the current task context 
+* physical addresses and the next task context physical address.
 ******************************************************************************/
 
@@ -11 +10 @@
 _task_switch:
 
+    /* desactivate DTLB */
+    ori         $27,    $0,             0xB
+    mtc2        $27,    $1                      /* DTLB desactivated */
+
     /* save _current task context */
-
     add     $27,    $4,     $0  /* $27 <= &context[curr_task_id] */
 
@@ -58 +60 @@
     mfc2    $26,    $0
     sw      $26,    35*4($27)   /* ctx[35] <= PTPR */
-    mfc2    $26,    $1
-    sw      $26,    36*4($27)   /* ctx[36] <= MODE */
 
     /* restore next task context */
-
     add     $27,    $5,     $0  /* $27<= &context[next_task_id] */
 
     lw      $26,    35*4($27)
     mtc2    $26,    $0          /* restore PTPR */
-    lw      $26,    36*4($27)
-    mtc2    $26,    $1          /* restore MODE */
     lw      $26,    0*4($27)
     mtc0    $26,    $12         /* restore SR */
@@ -111 +108 @@
     mtc0    $26,    $13         /* restore CR */
 
-    jr      $31                 /* returns to caller */
+    /* activate DTLB */
+    ori         $27,    $0,             0xF
+    mtc2        $27,    $1      
+
+    /* returns to caller */
+    jr      $31 
 
     .endfunc