diff options
| author | Victor Gallardo <vgallardo@apm.com> | 2010-09-16 11:32:04 -0700 |
|---|---|---|
| committer | Stefan Roese <sr@denx.de> | 2010-09-23 09:02:06 +0200 |
| commit | ad876fff342c67ca4536f7e2fec44c99498d8889 (patch) | |
| tree | 75217d83f79d94fec3226a1113ad6d13e11cc013 | |
| parent | e02d44964407716104c78d72170a086052c64e86 (diff) | |
ppc4xx: Disable trace broadcast for 44x non debug mode
By default the trace broadcast is enabled on 44x systems.
To reduce power consumption when instruction tracing is
not needed, disable trace broadcast.
Check External Debug Mode (EDM) bit to detect if it should be
disabled or not.
Resetting system via a debugger will set the DBCR0[EDM] bit.
Resetting via u-boot or OS will not.
Signed-off-by: Victor Gallardo <vgallardo@apm.com>
Signed-off-by: Stefan Roese <sr@denx.de>
| -rw-r--r-- | arch/powerpc/cpu/ppc4xx/start.S | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/ppc4xx/start.S b/arch/powerpc/cpu/ppc4xx/start.S index fcef0c21502..7a65d9fcc67 100644 --- a/arch/powerpc/cpu/ppc4xx/start.S +++ b/arch/powerpc/cpu/ppc4xx/start.S @@ -340,6 +340,9 @@ _start_440: mfspr r1,SPRN_DBCR0 andis. r1, r1, 0x8000 /* test DBCR0[EDM] bit */ bne skip_debug_init /* if set, don't clear debug register */ + mfspr r1,SPRN_CCR0 + ori r1,r1,CCR0_DTB@l /* Disable Trace Broadcast */ + mtspr SPRN_CCR0,r1 mtspr SPRN_DBCR0,r0 mtspr SPRN_DBCR1,r0 mtspr SPRN_DBCR2,r0 |