sync up with sources; fix initstk() to account for Tos

Reference: /n/atom/patch/applied2013/kisync
Date: Wed Jun 19 02:18:51 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/ki/ki.c	Wed Jun 19 02:18:31 2013
+++ /sys/src/cmd/ki/ki.c	Wed Jun 19 02:18:31 2013
@@ -2,6 +2,7 @@
 #include <libc.h>
 #include <bio.h>
 #include <mach.h>
+#include <tos.h>
 #define Extern
 #include "sparc.h"
 
@@ -277,12 +278,22 @@
 void
 initstk(int argc, char *argv[])
 {
-	ulong size, sp, ap;
+	ulong size, sp, ap, tos;
 	int i;
 	char *p;
 
 	initmap();
-	sp = STACKTOP - 4;
+	tos = STACKTOP - sizeof(Tos)*2;	/* we'll assume twice the host's is big enough */
+	sp = tos;
+	for (i = 0; i < sizeof(Tos)*2; i++)
+		putmem_b(tos + i, 0);
+
+	/*
+	 * pid is second word from end of tos and needs to be set for nsec().
+	 * we know sparc is a 32-bit cpu, so we'll assume knowledge of the Tos
+	 * struct for now, and use our pid.
+	 */
+	putmem_w(tos + 4*4 + 2*sizeof(ulong) + 3*sizeof(uvlong), getpid());
 
 	/* Build exec stack */
 	size = strlen(file)+1+BY2WD+BY2WD+(BY2WD*2);	
@@ -292,7 +303,7 @@
 	sp -= size;
 	sp &= ~7;
 	reg.r[1] = sp;
-	reg.r[7] = STACKTOP-4;	/* Plan 9 profiling clock */
+	reg.r[7] = tos;		/* Plan 9 profiling clock, etc. */
 
 	/* Push argc */
 	putmem_w(sp, argc+1);