hlt hlt is not a good idea. Rework APM to do what the spec actually says. Run actual BIOS calls whenever we are actually idle. Tovarisch!

ok deraadt@ toby@ beck@ weingart@ art@

2 files changed, 58 insertions, 29 deletions

diff --git a/sys/arch/i386/i386/apm.c b/sys/arch/i386/i386/apm.c
index 03a3a1bb880..14b9af1b773 100644
--- a/sys/arch/i386/i386/apm.c
+++ b/sys/arch/i386/i386/apm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: apm.c,v 1.64 2005/04/29 01:12:27 deraadt Exp $	*/
+/*	$OpenBSD: apm.c,v 1.65 2005/05/24 08:54:14 marco Exp $	*/
 
 /*-
  * Copyright (c) 1998-2001 Michael Shalayeff. All rights reserved.
@@ -147,6 +147,7 @@ u_char apm_minver;
 int apm_dobusy = 1;
 int apm_doidle = 1;
 int apm_bebatt = 0;
+int apm_idle_called = 0;
 
 struct {
 	u_int32_t entry;
@@ -624,34 +625,65 @@ apm_set_powstate(dev, state)
 }
 
 void
-apm_cpu_busy()
+apm_cpu_busy(void)
 {
 	struct apmregs regs;
-	if (!apm_cd.cd_ndevs || !apm_doidle)
+
+	if (!apm_cd.cd_ndevs)	/* No APM device, punt */
+		return;
+	if (!apm_dobusy)
+		return;
+	if (!apm_idle_called)
 		return;
-	bzero(&regs, sizeof(regs));
-	if ((apm_flags & APM_IDLE_SLOWS) &&
-		apmcall(APM_CPU_BUSY, 0, &regs) != 0) {
 
+	if (apm_flags & APM_IDLE_SLOWS) {
+		bzero(&regs, sizeof(regs));
+		if (apmcall(APM_CPU_BUSY, 0, &regs) != 0) {
 #ifdef DIAGNOSTIC
-		apm_perror("set CPU busy", &regs);
+			apm_perror("set CPU busy", &regs);
 #endif
+		}
+		apm_idle_called = 0;
 	}
 }
 
 void
-apm_cpu_idle()
+apm_cpu_idle(void)
 {
 	struct apmregs regs;
-	if (!apm_cd.cd_ndevs || !apm_doidle)
+	static int call_apm = 0;
+
+	if (!apm_cd.cd_ndevs) {	/* No APM device, wait for next interrupt */
+		__asm __volatile("sti;hlt");
 		return;
+	}
 
-	bzero(&regs, sizeof(regs));
-	if (apmcall(APM_CPU_IDLE, 0, &regs) != 0) {
+	if (!apm_doidle) {
+		__asm __volatile("sti;hlt");
+		return;
+	}
+		
+	/* 
+	 * We call the bios APM_IDLE routine here only when we 
+	 * have been idle for some time - otherwise we just hlt.
+	 */
 
+	if  (call_apm != curcpu()->ci_schedstate.spc_cp_time[CP_IDLE]) {
+		/* Always call BIOS halt/idle stuff */
+		bzero(&regs, sizeof(regs));
+		if (apmcall(APM_CPU_IDLE, 0, &regs) != 0) {
 #ifdef APMDEBUG
-		apm_perror("set CPU idle", &regs);
+			apm_perror("set CPU idle", &regs);
 #endif
+		}
+		apm_idle_called = 1;
+		/* If BIOS did halt, don't do it again! */
+		if (apm_flags & APM_IDLE_SLOWS) {
+			__asm __volatile("sti;hlt");
+		}
+		call_apm = curcpu()->ci_schedstate.spc_cp_time[CP_IDLE];
+	} else {
+		__asm __volatile("sti;hlt");
 	}
 }
 
@@ -893,6 +925,9 @@ apmattach(parent, self, aux)
 		setgdt(GAPM16CODE_SEL, NULL, 0, 0, 0, 0, 0);
 		setgdt(GAPMDATA_SEL, NULL, 0, 0, 0, 0, 0);
 	}
+	/* XXX - To go away */
+	printf("apm0: flags %x dobusy %d doidle %d\n",
+		apm_flags, apm_dobusy, apm_doidle);
 }
 
 void
diff --git a/sys/arch/i386/i386/locore.s b/sys/arch/i386/i386/locore.s
index 5254c3e7932..99ba37aacd8 100644
--- a/sys/arch/i386/i386/locore.s
+++ b/sys/arch/i386/i386/locore.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: locore.s,v 1.83 2005/04/17 07:33:13 tedu Exp $	*/
+/*	$OpenBSD: locore.s,v 1.84 2005/05/24 08:54:14 marco Exp $	*/
 /*	$NetBSD: locore.s,v 1.145 1996/05/03 19:41:19 christos Exp $	*/
 
 /*-
@@ -1599,22 +1599,22 @@ ENTRY(idle)
 	movl	$IPL_NONE,CPL		# spl0()
 	call	_C_LABEL(Xspllower)	# process pending interrupts
 
-ENTRY(idle_loop)
 	cmpl	$0,_C_LABEL(whichqs)
 	jnz	_C_LABEL(idle_exit)
-#if NAPM > 0
-	call	_C_LABEL(apm_cpu_idle)
-	cmpl	$0,_C_LABEL(apm_dobusy)
-	je	1f
-	call	_C_LABEL(apm_cpu_busy)
-1:
-#endif
+
+ENTRY(idle_loop)
 #if NPCTR > 0 && NAPM == 0
 	addl	$1,_C_LABEL(pctr_idlcnt)
 	adcl	$0,_C_LABEL(pctr_idlcnt)+4
+#endif
+#if NAPM > 0
+	call	_C_LABEL(apm_cpu_idle)
 #else
+	sti
 	hlt
 #endif
+	cmpl	$0,_C_LABEL(whichqs)
+	jnz	_C_LABEL(idle_exit)
 	jmp	_C_LABEL(idle_loop)
 
 ENTRY(idle_exit)
@@ -1622,16 +1622,10 @@ ENTRY(idle_exit)
 #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG)	
 	call	_C_LABEL(sched_lock_idle)
 #endif
-#if 0
-	GET_CPUINFO(%ebx)
-	leal	CPU_INFO_NAME(%ebx),%ebx
-	pushl	%ebx
-	pushl	$1f
-	call	_C_LABEL(printf)
-	addl	$8,%esp
+#if NAPM > 0
+	call	_C_LABEL(apm_cpu_busy)
 #endif
 	jmp	switch_search
-1:	.asciz	"%s: unidle\n"
 		
 #ifdef DIAGNOSTIC
 NENTRY(switch_error)