Changeset 301 for soft/giet_vm/giet_kernel

Timestamp:

Apr 14, 2014, 6:44:51 PM (11 years ago)

Author:

cfuguet

Message:

Bugfix for interrupt masking and demasking.

Location:

soft/giet_vm/giet_kernel

Files:

• giet.s (modified) (2 diffs)
• switch.s (modified) (3 diffs)
• sys_handler.c (modified) (1 diff)

soft/giet_vm/giet_kernel/giet.s

@@ -56 +56 @@
 _sys_handler:
     addiu   $29,    $29,    -24     /* 2 slots for SR&EPC, 4 slots for args passing */
-    mfc0    $26,    $12             /* load SR */
-    sw      $26,    16($29)         /* save it in the stack */
     mfc0    $27,    $14             /* load EPC */
     addiu   $27,    $27,    4       /* increment EPC for return address */
@@ -73 +71 @@
     mtc0    $26,    $12             /* interrupt enabled */
     jalr    $3                      /* jump to the proper syscall */
-    mtc0    $0,     $12             /* interrupt disbled */
 
-    lw      $26,    16($29)         /* load SR from stack */
-    mtc0    $26,    $12             /* restore SR */
+    mfc0    $26,    $12             /* load SR */
+    ori     $26,    $26,    0x2     /* set EXL bit */
+    mtc0    $26,    $12
+
     lw      $26,    20($29)         /* load EPC from stack */
     mtc0    $26,    $14             /* restore EPC */
-    addiu   $29,    $29,     24     /* restore stack pointer */
+    addiu   $29,    $29,    24      /* restore stack pointer */
     eret                            /* exit GIET */
 

soft/giet_vm/giet_kernel/switch.s

@@ -2 +2 @@
 * This function receives two arguments that are the current task context 
 * (virtual) addresses and the next task context (virtual) address.
+*
+* This function should be called in a critical section
 *
 * TODO (AG) Il semble possible de limiter le nombre de registres à sauver:
@@ -18 +20 @@
 
 _task_switch:
-
-    /* enter critical section */
-    li      $2,     0xFFFFFFFE  
-    mfc0    $3,     $12        
-    and     $3,     $3, $2    
-    mtc0    $3,     $12    
 
     /* save _current task context */
@@ -123 +119 @@
     mtc2    $26,    $0          /* restore PTPR */
 
-    /* exit critical section */
-    li      $2,     0x00000001  
-    mfc0    $3,     $12        
-    or      $3,     $3, $2    
-    mtc0    $3,     $12    
-
     /* returns to caller */
     jr      $31 

soft/giet_vm/giet_kernel/sys_handler.c

@@ -55 +55 @@
     &_sys_ukn,             /* 0x17 */
     &_sys_ukn,             /* 0x18 */   
-    &_ctx_switch,          /* 0x19 */
+    &_context_switch,      /* 0x19 */
     &_vobj_get_vbase,      /* 0x1A */
     &_sys_ukn,             /* 0x1B */