Add a special OpenFirmware entry point for terminating the kernel (in

this case, the firmware trap table needs to be restored). Make use of
it in cpu_halt() and cpu_reset(), and make cpu_reset() reboot the kernel
that was used previously insead of behaving like cpu_halt().
Add a shutdown_final event handler that turns the power off if requested.

sys/sparc64/sparc64/db_interface.c

@@ -108,3 +108,8 @@ DB_COMMAND(reboot, db_reboot)
 {
 	cpu_reset();
 }
+
+DB_COMMAND(halt, db_halt)
+{
+	cpu_halt();
+}

sys/sparc64/sparc64/machdep.c

@@ -58,6 +58,7 @@
 #include <sys/bio.h>
 #include <sys/buf.h>
 #include <sys/bus.h>
+#include <sys/eventhandler.h>
 #include <sys/interrupt.h>
 #include <sys/ptrace.h>
 #include <sys/signalvar.h>
@@ -86,6 +87,7 @@
 #include <machine/fp.h>
 #include <machine/intr_machdep.h>
 #include <machine/md_var.h>
+#include <machine/ofw_machdep.h>
 #include <machine/pmap.h>
 #include <machine/pstate.h>
 #include <machine/reg.h>
@@ -131,6 +133,7 @@ static struct timecounter tick_tc;
 
 static timecounter_get_t tick_get_timecount;
 void sparc64_init(struct bootinfo *bi, ofw_vec_t *vec);
+void sparc64_shutdown_final(void *dummy, int howto);
 
 static void cpu_startup(void *);
 SYSINIT(cpu, SI_SUB_CPU, SI_ORDER_FIRST, cpu_startup, NULL);
@@ -171,6 +174,9 @@ cpu_startup(void *arg)
 
 	intr_init();
 	tick_start(clock, tick_hardclock);
+
+	EVENTHANDLER_REGISTER(shutdown_final, sparc64_shutdown_final, NULL,
+	    SHUTDOWN_PRI_LAST);
 }
 
 unsigned
@@ -477,11 +483,47 @@ sigreturn(struct thread *td, struct sigreturn_args *uap)
 	return (EJUSTRETURN);
 }
 
+/*
+ * Duplicate OF_exit() with a different firmware call function that restores
+ * the trap table, otherwise a RED state exception is triggered in at least
+ * some firmware versions.
+ */
 void
 cpu_halt(void)
 {
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+	} args = {
+		(cell_t)"exit",
+		0,
+		0
+	};
 
-	OF_exit();
+	openfirmware_exit(&args);
+}
+
+void
+sparc64_shutdown_final(void *dummy, int howto)
+{
+	static struct {
+		cell_t name;
+		cell_t nargs;
+		cell_t nreturns;
+	} args = {
+		(cell_t)"SUNW,power-off",
+		0,
+		0
+	};
+
+	/* Turn the power off? */
+	if ((howto & RB_POWEROFF) != 0)
+		openfirmware_exit(&args);
+	/* In case of halt, return to the firmware */
+	if ((howto & RB_HALT) != 0)
+		cpu_halt();
+		
 }
 
 int

sys/sparc64/sparc64/support.S

@@ -604,3 +604,27 @@ ENTRY(openfirmware)
 	ret
 	 restore %o0, %g0, %o0
 END(openfirmware)
+
+/*
+ * void ofw_exit(cell_t args[])
+ */
+ENTRY(openfirmware_exit)
+	save	%sp, -CCFSZ, %sp
+	flushw
+	wrpr	%g0, PIL_TICK, %pil
+	setx	ofw_tba, %l7, %l5
+	ldx	[%l5], %l5
+	wrpr	%l5, 0, %tba			! restore the ofw trap table
+	setx	ofw_vec, %l7, %l6
+	ldx	[%l6], %l6
+	setx	kstack0 + KSTACK_PAGES * PAGE_SIZE - PCB_SIZEOF, %l7, %l0
+	sub	%l0, SPOFF, %fp			! setup a stack in a locked page
+	sub	%l0, SPOFF + CCFSZ, %sp
+	mov     AA_DMMU_PCXR, %l3		! set context 0
+	stxa    %g0, [%l3] ASI_DMMU
+	membar  #Sync
+	wrpr	%g0, 0, %tl			! force trap level 0
+	call	%l6
+	 mov	%i0, %o0
+	! never to return
+END(openfirmware_exit)

sys/sparc64/sparc64/support.s

@@ -604,3 +604,27 @@ ENTRY(openfirmware)
 	ret
 	 restore %o0, %g0, %o0
 END(openfirmware)
+
+/*
+ * void ofw_exit(cell_t args[])
+ */
+ENTRY(openfirmware_exit)
+	save	%sp, -CCFSZ, %sp
+	flushw
+	wrpr	%g0, PIL_TICK, %pil
+	setx	ofw_tba, %l7, %l5
+	ldx	[%l5], %l5
+	wrpr	%l5, 0, %tba			! restore the ofw trap table
+	setx	ofw_vec, %l7, %l6
+	ldx	[%l6], %l6
+	setx	kstack0 + KSTACK_PAGES * PAGE_SIZE - PCB_SIZEOF, %l7, %l0
+	sub	%l0, SPOFF, %fp			! setup a stack in a locked page
+	sub	%l0, SPOFF + CCFSZ, %sp
+	mov     AA_DMMU_PCXR, %l3		! set context 0
+	stxa    %g0, [%l3] ASI_DMMU
+	membar  #Sync
+	wrpr	%g0, 0, %tl			! force trap level 0
+	call	%l6
+	 mov	%i0, %o0
+	! never to return
+END(openfirmware_exit)

sys/sparc64/sparc64/vm_machdep.c

@@ -61,6 +61,7 @@
 #include <machine/cpu.h>
 #include <machine/frame.h>
 #include <machine/md_var.h>
+#include <machine/ofw_machdep.h>
 #include <machine/tstate.h>
 
 void
@@ -88,7 +89,9 @@ cpu_fork(struct thread *td1, struct proc *p2, int flags)
 		return;
 
 	td2 = &p2->p_thread;
-	pcb = (struct pcb *)(td2->td_kstack + KSTACK_PAGES * PAGE_SIZE) - 1;
+	/* The pcb must be aligned on a 64-byte boundary. */
+	pcb = (struct pcb *)((td2->td_kstack + KSTACK_PAGES * PAGE_SIZE -
+	    sizeof(struct pcb)) & ~0x3fUL);
 	td2->td_pcb = pcb;
 
 	/*
@@ -136,7 +139,26 @@ cpu_fork(struct thread *td1, struct proc *p2, int flags)
 void
 cpu_reset(void)
 {
-	OF_exit();
+	static char bspec[64] = "";
+	phandle_t chosen;
+	static struct {
+		cell_t	name;
+		cell_t	nargs;
+		cell_t	nreturns;
+		cell_t	bootspec;
+	} args = {
+		(cell_t)"boot",
+		1,
+		0,
+		(cell_t)bspec
+	};
+	if ((chosen = OF_finddevice("/chosen")) != 0) {
+		if (OF_getprop(chosen, "bootpath", bspec, sizeof(bspec)) == -1)
+			bspec[0] = '\0';
+		bspec[sizeof(bspec) - 1] = '\0';
+	}
+		
+	openfirmware_exit(&args);
 }
 
 /*