ARM: imx: always use TWD on IMX6Q
authorSebastian Andrzej Siewior <bigeasy@linutronix.de>
Wed, 6 Apr 2016 15:39:07 +0000 (17:39 +0200)
committerShawn Guo <shawnguo@kernel.org>
Tue, 12 Apr 2016 07:56:55 +0000 (15:56 +0800)
There is no reason to limit the TWD to be used on SMP kernels only if the
hardware has it available.
On Wandboard i.MX6SOLO, running PREEMPT-RT and cyclictest I see as max
immediately after start in idle:
UP : ~90us
SMP: ~50us
UP + TWD: ~20us.
Based on this numbers I prefer the TWD over the slightly slower MXC
timer.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
arch/arm/mach-imx/Kconfig

index 8973fae25436b1fcd5424dd5c7ed994ae68ed43a..dd905b9602a02d53ebe86764aaf00dbbc4dbe1da 100644 (file)
@@ -526,7 +526,7 @@ config SOC_IMX6Q
        bool "i.MX6 Quad/DualLite support"
        select ARM_ERRATA_764369 if SMP
        select HAVE_ARM_SCU if SMP
-       select HAVE_ARM_TWD if SMP
+       select HAVE_ARM_TWD
        select PCI_DOMAINS if PCI
        select PINCTRL_IMX6Q
        select SOC_IMX6