Changeset 801 for trunk/softs/tsar_boot/src

Timestamp:

Sep 12, 2014, 3:10:03 PM (10 years ago)

Author:

cfuguet

Message:

tsar_boot: Using P_WIDTH constant to get lpid from CP0 EBASE

File:

• trunk/softs/tsar_boot/src/reset.S (modified) (1 diff)

trunk/softs/tsar_boot/src/reset.S

@@ -79 +79 @@
     mtc0    k0,     CP0_STATUS
 
-    /* All processors compute pid, lpid, cluster_xy */
+    /*
+     * All processors compute gpid, lpid, cluster_xy
+     * gpid = ebase[9:0] = X_WIDTH : Y_WIDTH : P_WIDTH
+     *                        x         y       lpid
+     * X, Y and LPID fields are left-aligned
+     */
 
     mfc0    k0,     CP0_EBASE
-    andi    t0,     k0,     0x3FF    /* t0 <= pid (at most 1024 procs)      */
-
-    move    t3,     t0
-
-    la      k0,     NB_PROCS_MAX     /* k0 <= # of processors per cluster   */
-    divu    t3,     k0
-    mfhi    t1                       /* t1 <= lpid       = pid % NB_PROCS   */
-    mflo    t2                       /* t2 <= cluster_xy = pid / NB_PROCS   */
+    andi    t0,     k0,     0x3FF            /* t0 <= gpid (<= 1024 procs)  */
+    andi    t1,     t0,     ((1<<P_WIDTH)-1) /* t1 <= lpid                  */
+    srl     t2,     t0,     P_WIDTH          /* t2 <= cluster_xy            */
 
     /* All processors initialise the count register in CP0 */