summaryrefslogtreecommitdiff
path: root/arch/powerpc/platforms/powernv/Kconfig
diff options
context:
space:
mode:
authorMichael Neuling <mikey@neuling.org>2014-06-11 15:59:28 +1000
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>2014-06-11 17:05:12 +1000
commitd4e58e5928f8c6c49228451dd03e0714cbab299a (patch)
tree34add9a16b4dbe03da04191f51588f3f6a6bdbf9 /arch/powerpc/platforms/powernv/Kconfig
parent9b6a68d94333cf19d4ec0f2aaf9f9eb68866630e (diff)
powerpc/powernv: Enable POWER8 doorbell IPIs
This patch enables POWER8 doorbell IPIs on powernv. Since doorbells can only IPI within a core, we test to see when we can use doorbells and if not we fall back to XICS. This also enables hypervisor doorbells to wakeup us up from nap/sleep via the LPCR PECEDH bit. Based on tests by Anton, the best case IPI latency between two threads dropped from 894ns to 512ns. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/platforms/powernv/Kconfig')
-rw-r--r--arch/powerpc/platforms/powernv/Kconfig1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platforms/powernv/Kconfig
index c252ee95bddf..45a8ed0585cd 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -17,6 +17,7 @@ config PPC_POWERNV
select CPU_FREQ_GOV_USERSPACE
select CPU_FREQ_GOV_ONDEMAND
select CPU_FREQ_GOV_CONSERVATIVE
+ select PPC_DOORBELL
default y
config PPC_POWERNV_RTAS