aboutsummaryrefslogtreecommitdiff
path: root/sys/powerpc/booke/swtch.S
diff options
context:
space:
mode:
authorRafal Jaworowski <raj@FreeBSD.org>2009-02-27 12:08:24 +0000
committerRafal Jaworowski <raj@FreeBSD.org>2009-02-27 12:08:24 +0000
commit0a35b40f8dd4af0203eba5b31c73c80b10176c37 (patch)
tree8b41f61a7208bd8888ebad2d80a7da1d913c93f4 /sys/powerpc/booke/swtch.S
parent2a4f4fc1965e4fe365ee6ac97cebe26c19166d82 (diff)
downloadsrc-0a35b40f8dd4af0203eba5b31c73c80b10176c37.tar.gz
src-0a35b40f8dd4af0203eba5b31c73c80b10176c37.zip
Make Book-E debug register state part of the PCB context.
Previously, DBCR0 flags were set "globally", but this leads to problems because Book-E fine grained debug settings work only in conjuction with the debug master enable bit in MSR: in scenarios when the DBCR0 was set with intention to debug one process, but another one with MSR[DE] set got scheduled, the latter would immediately cause debug exceptions to occur upon execution of its own code instructions (and not the one intended for debugging). To avoid such problems and properly handle debugging context, DBCR0 state should be managed individually per process. Submitted by: Grzegorz Bernacki gjb ! semihalf dot com Reviewed by: marcel
Notes
Notes: svn path=/head/; revision=189100
Diffstat (limited to 'sys/powerpc/booke/swtch.S')
-rw-r--r--sys/powerpc/booke/swtch.S5
1 files changed, 5 insertions, 0 deletions
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