4 files changed, 14 insertions, 5 deletions
diff --git a/sys/powerpc/booke/machdep.c b/sys/powerpc/booke/machdep.c
index 1803ef23abc5..e42aa8c77f0c 100644
--- a/sys/powerpc/booke/machdep.c
+++ b/sys/powerpc/booke/machdep.c
@@ -806,14 +806,10 @@ int
 ptrace_single_step(struct thread *td)
 {
 	struct trapframe *tf;
-	u_int reg;
-
-	reg = mfspr(SPR_DBCR0);
-	reg |= DBCR0_IC | DBCR0_IDM;
-	mtspr(SPR_DBCR0, reg);
 
 	tf = td->td_frame;
 	tf->srr1 |= PSL_DE;
+	tf->cpu.booke.dbcr0 |= (DBCR0_IDM | DBCR0_IC);
 	return (0);
 }
 
@@ -824,6 +820,7 @@ ptrace_clear_single_step(struct thread *td)
 
 	tf = td->td_frame;
 	tf->srr1 &= ~PSL_DE;
+	tf->cpu.booke.dbcr0 &= ~(DBCR0_IDM | DBCR0_IC);
 	return (0);
 }
 
diff --git a/sys/powerpc/booke/swtch.S b/sys/powerpc/booke/swtch.S
index 80bf2b3a459a..bfd7dd2c2204 100644
--- a/sys/powerpc/booke/swtch.S
+++ b/sys/powerpc/booke/swtch.S
@@ -66,6 +66,7 @@
 #include <machine/param.h>
 #include <machine/psl.h>
 #include <machine/asm.h>
+#include <machine/spr.h>
 
 /*
  * void cpu_switch(struct thread *old, struct thread *new)
@@ -87,6 +88,8 @@ ENTRY(cpu_switch)
 	stw	%r16, PCB_BOOKE_CTR(%r5)
 	mfxer	%r16
 	stw	%r16, PCB_BOOKE_XER(%r5)
+	mfspr	%r16, SPR_DBCR0
+	stw	%r16, PCB_BOOKE_DBCR0(%r5)
 
 	stw	%r1, PCB_SP(%r5)	/* Save the stack pointer */
 
@@ -114,6 +117,8 @@ ENTRY(cpu_switch)
 	mtctr	%r5
 	lwz	%r5, PCB_BOOKE_XER(%r3)
 	mtxer	%r5
+	lwz	%r5, PCB_BOOKE_DBCR0(%r3)
+	mtspr	SPR_DBCR0, %r5
 
 	lwz	%r1, PCB_SP(%r3)	/* Load the stack pointer */
 	blr
diff --git a/sys/powerpc/booke/trap.c b/sys/powerpc/booke/trap.c
index 88a0a51d9fd7..0e746f4f0c79 100644
--- a/sys/powerpc/booke/trap.c
+++ b/sys/powerpc/booke/trap.c
@@ -187,6 +187,7 @@ trap(struct trapframe *frame)
 		case EXC_DEBUG:	/* Single stepping */
 			mtspr(SPR_DBSR, mfspr(SPR_DBSR));
 			frame->srr1 &= ~PSL_DE;
+			frame->cpu.booke.dbcr0 &= ~(DBCR0_IDM || DBCR0_IC);
 			sig = SIGTRAP;
 			break;
 
diff --git a/sys/powerpc/booke/trap_subr.S b/sys/powerpc/booke/trap_subr.S
index f7a54a63146b..2a5820dbd2ca 100644
--- a/sys/powerpc/booke/trap_subr.S
+++ b/sys/powerpc/booke/trap_subr.S
@@ -207,6 +207,9 @@
 	stw	%r4, FRAME_CTR+8(1);					\
 	li	%r5, exc;						\
 	stw	%r5, FRAME_EXC+8(1);					\
+	/* save DBCR0 */						\
+	mfspr	%r3, SPR_DBCR0;						\
+	stw	%r3, FRAME_BOOKE_DBCR0+8(1);				\
 	/* save xSSR0-1 */						\
 	lwz	%r30, (savearea+CPUSAVE_SRR0)(%r2);			\
 	lwz	%r31, (savearea+CPUSAVE_SRR1)(%r2);			\
@@ -231,6 +234,9 @@
 	mtxer	%r5;							\
 	mtlr	%r6;							\
 	mtcr	%r7;							\
+	/* restore DBCR0 */						\
+	lwz	%r4, FRAME_BOOKE_DBCR0+8(%r1);				\
+	mtspr	SPR_DBCR0, %r4;						\
 	/* restore xSRR0-1 */						\
 	lwz	%r30, FRAME_SRR0+8(%r1);				\
 	lwz	%r31, FRAME_SRR1+8(%r1);				\