$NetBSD: patch-ag,v 1.7 2003/06/06 08:58:43 jtb Exp $

--- /dev/null
+++ config/netbsd/sparc.c
@@ -0,0 +1,33 @@
+/*
+ * coswitch for NetBSD SPARC
+ */
+
+int
+coswitch (int *old_cs, int *new_cs, int first)
+{
+   asm("ta     0x03");                 /* ST_FLUSH_WINDOWS in trap.h     */
+   asm("ld     [%fp+0x44], %o0");      /* load old_cs into %o0           */
+   asm("st     %sp,[%o0]");            /* Save user stack pointer        */
+   asm("st     %fp,[%o0+0x4]");        /* Save frame pointer             */
+   asm("st     %i7,[%o0+0x8]");        /* Save return address            */
+
+   if (first == 0) {                   /* this is the first activation   */
+      asm("ld  [%fp+0x48], %o0");      /* load new_cs into %o0           */
+      asm("ld  [%o0], %o1");           /* load %o1 from cstate[0]        */
+
+      /* Decrement new stack pointer value before loading it into sp.    */
+      /* The top 64 bytes of the stack are reserved for the kernel, to   */
+      /* save the 8 local and 8 in registers into, on context switches,  */
+      /* interrupts, traps, etc.                                         */
+
+      asm("save  %o1,-96, %sp");       /* load %sp from %o1              */
+      new_context(0,0);
+      syserr("new_context() returned in coswitch");
+
+   } else {
+      asm("ld  [%fp+0x48], %o0");      /* load new_cs into %o0           */
+      asm("ld  [%o0+0x4],%fp");        /* Load frame pointer             */
+      asm("ld  [%o0+0x8],%i7");        /* Load return address            */
+      asm("ld  [%o0],%sp");            /* Load user stack pointer        */
+   }
+}