--- xinu/sys/clkint.s	2018/04/24 17:39:04	1.1
+++ xinu/sys/clkint.s	2018/04/24 17:39:46	1.1.1.2
@@ -1,53 +1,49 @@
-/* clkint.s -  clkint */
-
-#include <procreg.h>
-#include <conf.h>
-
-/*------------------------------------------------------------------------
- * clkint  --  real-time clock interrupt service routine 
- *------------------------------------------------------------------------
-*/
-
-					/* define constants		*/
-#define	CLEARINT 0xc1			/* value to clear ICCS INT bit	*/
+|* clkint.s -  clkint
 
+|*------------------------------------------------------------------------
+|* clkint  --  real-time clock interrupt service routine 
+|*------------------------------------------------------------------------
 	.text
-	.align	2			/* align on longword boundary	*/
 	.globl	_clkint
+	.globl _tstat
 _clkint:
-	mtpr	$DISABLE, $IPL		/* disable interrupts		*/
-#if !defined(UVAX)
-	mtpr	$CLEARINT, $ICCS	/* clr interrupt bit in interval*/
-					/* clock control reg 		*/
-#else 					/* Microvax has a 10ms rt clock	*/
-	decl	_count10		/* Is this the 10th interrupt?	*/
-	jnequ	clret			/*  no => return		*/
-	movl	$10, _count10		/*  yes=> reset counter&continue*/
+	movl	a0,sp@-			| save a0
+	movl	_tstat,a0		| address of hardware reg to ack tick
+#ifdef ATT7300
+| clock owns one bit of miscellaneous control reg--maintain other bits--
+	movl	d0,sp@-
+	movw    _soft_mcr7300,d0	| normal value for MCR
+	andw	#0x7fff,d0		| clear high bit
+	movw	d0,a0@			| acknowledge clock tick
+	movw    _soft_mcr7300,a0@	|   with low-high on high bit of MCR
+	movl    sp@+,d0
+#else
+	movb	#1,a0@			| acknowledge clock tick
 #endif
-	decl	_tickctr		/* Is this the 10th tick?	*/
-	jnequ	clckdef			/*  no => process tick		*/
-	movl	$10, _tickctr		/*  yes=> reset counter&continue*/
-	incl	_clktime		/* increment time-of-day clock	*/
-clckdef:
-	tstl	_defclk			/* Are clock ticks deferred?	*/
-	jeqlu	notdef			/*  no => go process this tick	*/
-	incl	_clkdiff		/*  yes=> count in clkdiff and	*/
-	rei				/*	  return quickly	*/
-notdef:
-	tstl	_slnempty		/* Is sleep queue nonempty?	*/
-	jeqlu	clpreem			/* no => go process preemption	*/
-	decw	*_sltop			/* yes=> decrement delta key	*/
-	jnequ	clpreem			/* 	 on first process,	*/
-					/* 	 calling wakeup if 0	*/
-	pushr	$LOWREGS		/* save low registers		*/
-	calls	$0, _wakeup		/* wakeup sleeping process	*/
-	popr	$LOWREGS		/* restore low registers	*/
+	movl 	sp@+,a0			| restore a0
+	subql	#1,_count6		| Is this the 6th interrupt?
+	bpl	clret			|  no => return
+	movl	#6,_count6		|  yes=> reset counter&continue
+	tstl     _defclk		| Are clock ticks deferred?
+	beq     notdef			|  no => skip down
+	addql	#1,_clkdiff		|  yes=> count in clkdiff and
+	rte				|        return quickly
+notdef:	
+	tstl     _slnempty		| Is sleep queue empty?
+	beq     clpreem			|  yes=> skip down
+	movl	a0,sp@-			| save a0
+	movl 	_sltop,a0		|  no => decrement delta key
+	subql	#1,a0@			|        of first process
+	movl	sp@+,a0			| restore a0, cc's unaffected
+	bpl     clpreem			|  ck if ready to wake up
+	moveml	#0xc0c0,sp@-		| Save d0,d1,a0,a1 - C scratch regs
+	jsr	_wakeup			|     
+	moveml	sp@+,#0x0303		| Restore d0,d1,a0,a1
 clpreem:
-	decl	_preempt		/* decrement preemption counter	*/
-	jnequ	clret			/* and call resched if it is 0	*/
-	pushr	$LOWREGS		/* save low registers		*/
-	calls	$0, _resched		/* reschedule			*/
-	popr	$LOWREGS		/* restore low registers	*/
+	subql	#1,_preempt		| Decrement preemption counter
+	bpl	clret			|   and call resched if it
+	moveml	#0xc0c0,sp@-
+	jsr	_resched
+	moveml	sp@+,#0x0303
 clret:
-	rei				/* restore pre-interrupt IPL &	*/
-					/* return from interrupt	*/
+	rte				| Return from interrupt