[PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q

Steven Rostedt
2016-07-12T14:27:02Z

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4.1.27-rt31-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

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: Steven Rostedt <rostedt@goodmis.org>
---
arch/arm/mach-imx/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 3a3d3e9d7bfd..92c0cf1276fe 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -558,7 +558,7 @@ 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
--
2.8.1