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

From	Steven Rostedt <rostedt@goodmis.org>
Newsgroups	linux.kernel
Subject	[PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q
Date	2016-07-12 16:30 +0200
Message-ID	<rU6Rc-66R-43@gated-at.bofh.it> (permalink)
References	<rU6Rb-66R-3@gated-at.bofh.it>
Organization	linux.* mail to news gateway

Show all headers | View raw

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

Back to linux.kernel | Previous | Next — Next in thread | Find similar | Unroll thread

Thread

[PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q Steven Rostedt <rostedt@goodmis.org> - 2016-07-12 16:30 +0200
  Re: [PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-07-12 22:10 +0200
    Re: [PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q Steven Rostedt <rostedt@goodmis.org> - 2016-07-12 22:30 +0200
    Re: [PATCH RT 11/20] ARM: imx: always use TWD on IMX6Q Grygorii Strashko <grygorii.strashko@ti.com> - 2016-07-18 20:20 +0200

csiph-web