patch: power off

Hi,

Current x68k kernel supports software power-off (by sysmon(4)),
but in fact, the kernel does not turn off the power.  Power off
is happened in IPLROM after software reset.

So, I wrote a patch that the kernel does power off itself.
Any comments?

I have tested only on XM6i because my X68030 has failed.  I'm
happy if someone could test it on the real machine.

# By the way, if you are using my x68k-pxhtc-yyyymmdd.diff patch
# on XM6i, you can use these patches at the same time, by rewriting
# WITH_PXHTC to 1 in following patch.
---
Tetsuya Isaki <[email protected] / [email protected]>

Index: sys/arch/x68k/x68k/locore.s
===================================================================
RCS file: /cvsroot/src/sys/arch/x68k/x68k/locore.s,v
retrieving revision 1.117
diff -u -r1.117 locore.s
--- sys/arch/x68k/x68k/locore.s	22 Mar 2014 21:49:18 -0000	1.117
+++ sys/arch/x68k/x68k/locore.s	23 Mar 2014 10:01:35 -0000
@@ -898,7 +898,14 @@
  * is turned off.  We have conveniently mapped the last page of physical
  * memory this way.
  */
+ENTRY_NOPROFILE(dopoweroff)
+	movql	#1,%d1			| shutdown
+	bra	Ldoboot_main
+
 ENTRY_NOPROFILE(doboot)
+	movql	#0,%d1			| reboot
+
+Ldoboot_main:
 	movw	#PSL_HIGHIPL,%sr	| cut off any interrupts
 	subal	%a1,%a1			| a1 = 0
 
@@ -915,18 +922,43 @@
 	movc	%d0,%cacr		| disable on-chip cache(s)
 
 	| ok, turn off MMU..
-Ldoreboot:
 #if defined(M68040) || defined(M68060)
 	tstl	%d2			| 68040?
 	jne	LmotommuF		| no, skip
 	movc	%a1,%cacr		| caches off
 	.long	0x4e7b9003		| movc a1(=0),tc ; disable MMU
-	jra	Ldoreboot1
+	jra	Ldoboot1
 LmotommuF:
 #endif
 	clrl	%sp@
 	pmove	%sp@,%tc		| disable MMU
-Ldoreboot1:
+
+Ldoboot1:
+	/* Reset the stack pointer after MMU disabled */
+	subal	%a5,%a5			| XXX firstpa=0 because PA==VA
+	ASRELOC(tmpstk, %a0)
+	movl	%a0,%sp
+
+	tstl	%d1			| %d1 = shutdown or reboot
+	beq	Ldoreboot
+
+	leal	0xe8e00f,%a0		| write a power-off sequence
+	movb	#0x00,%a0@		|  to system port
+	movb	#0x0f,%a0@
+	movb	#0x0f,%a0@
+
+	movl	#1000000,%sp@-		| wait a bit
+#define WITH_PXHTC 0
+#if WITH_PXHTC /* with pxhtc patch, delay is a pointer to function */
+	RELOC(delay, %a0)
+	moval	%a0@,%a0
+	jsr	%a0@
+#else /* without pxhtc patch, delay is local label */
+	bsr	_delay
+#endif
+	/* PASSTHROUGH */		| passthrough even if came back
+
+Ldoreboot:
 	moveml	0x00ff0000,#0x0101	| get RESET vectors in ROM
 					|	(d0: ssp, a0: pc)
 	moveml	#0x0101,%a1@		| put them at 0x0000 (for Xellent30)
Index: sys/arch/x68k/x68k/machdep.c
===================================================================
RCS file: /cvsroot/src/sys/arch/x68k/x68k/machdep.c,v
retrieving revision 1.188
diff -u -r1.188 machdep.c
--- sys/arch/x68k/x68k/machdep.c	22 Mar 2014 21:49:18 -0000	1.188
+++ sys/arch/x68k/x68k/machdep.c	23 Mar 2014 10:01:36 -0000
@@ -108,6 +108,7 @@
 #include <arch/x68k/dev/intiovar.h>
 
 extern void doboot(void) __attribute__((__noreturn__));
+extern void dopoweroff(void) __attribute__((__noreturn__));
 
 /* the following is used externally (sysctl_hw) */
 char	machine[] = MACHINE;	/* from <machine/param.h> */
@@ -523,10 +524,9 @@
 	 * c) otherwise
 	 *	Reboot
 	 */
-	if (((howto & RB_POWERDOWN) == RB_POWERDOWN) && power_switch_is_off)
-		doboot();
-	else if (/*((howto & RB_POWERDOWN) == RB_POWERDOWN) ||*/
-		 ((howto & RB_HALT) == RB_HALT)) {
+	if (((howto & RB_POWERDOWN) == RB_POWERDOWN) && power_switch_is_off) {
+		dopoweroff();
+	} else if ((howto & RB_HALT) == RB_HALT) {
 		printf("System halted.  Hit any key to reboot.\n\n");
 		(void)cngetc();
 	}