From: Sudeep Holla <sudeep.holla@arm.com> To: linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Sudeep Holla <sudeep.holla@arm.com>, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>, Daniel Lezcano <daniel.lezcano@linaro.org>, "Rafael J. Wysocki" <rjw@rjwysocki.net> Subject: [PATCH] drivers: cpuidle: don't initialize big.LITTLE driver if MCPM is unavailable Date: Thu, 8 Jan 2015 06:29:04 +0000 [thread overview] Message-ID: <1420698544-10277-1-git-send-email-sudeep.holla@arm.com> (raw) If big.LITTLE driver is initialized even when MCPM is unavailable, we get the below warning the first time cpu tries to enter deeper C-states. ------------[ cut here ]------------ WARNING: CPU: 4 PID: 0 at kernel/arch/arm/common/mcpm_entry.c:130 mcpm_cpu_suspend+0x6d/0x74() Modules linked in: CPU: 4 PID: 0 Comm: swapper/4 Not tainted 3.19.0-rc3-00007-gaf5a2cb1ad5c-dirty #11 Hardware name: ARM-Versatile Express [<c0013fa5>] (unwind_backtrace) from [<c001084d>] (show_stack+0x11/0x14) [<c001084d>] (show_stack) from [<c04fe7f1>] (dump_stack+0x6d/0x78) [<c04fe7f1>] (dump_stack) from [<c0020645>] (warn_slowpath_common+0x69/0x90) [<c0020645>] (warn_slowpath_common) from [<c00206db>] (warn_slowpath_null+0x17/0x1c) [<c00206db>] (warn_slowpath_null) from [<c001cbdd>] (mcpm_cpu_suspend+0x6d/0x74) [<c001cbdd>] (mcpm_cpu_suspend) from [<c03c6919>] (bl_powerdown_finisher+0x21/0x24) [<c03c6919>] (bl_powerdown_finisher) from [<c001218d>] (cpu_suspend_abort+0x1/0x14) [<c001218d>] (cpu_suspend_abort) from [<00000000>] ( (null)) ---[ end trace d098e3fd00000008 ]--- This patch fixes the issue by checking for the availability of MCPM before initializing the big.LITTLE cpuidle driver Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> --- drivers/cpuidle/cpuidle-big_little.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index e3e225fe6b45..40c34faffe59 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -182,6 +182,10 @@ static int __init bl_idle_init(void) */ if (!of_match_node(compatible_machine_match, root)) return -ENODEV; + + if (!mcpm_is_available()) + return -EUNATCH; + /* * For now the differentiation between little and big cores * is based on the part number. A7 cores are considered little -- 1.9.1
WARNING: multiple messages have this Message-ID (diff)
From: sudeep.holla@arm.com (Sudeep Holla) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] drivers: cpuidle: don't initialize big.LITTLE driver if MCPM is unavailable Date: Thu, 8 Jan 2015 06:29:04 +0000 [thread overview] Message-ID: <1420698544-10277-1-git-send-email-sudeep.holla@arm.com> (raw) If big.LITTLE driver is initialized even when MCPM is unavailable, we get the below warning the first time cpu tries to enter deeper C-states. ------------[ cut here ]------------ WARNING: CPU: 4 PID: 0 at kernel/arch/arm/common/mcpm_entry.c:130 mcpm_cpu_suspend+0x6d/0x74() Modules linked in: CPU: 4 PID: 0 Comm: swapper/4 Not tainted 3.19.0-rc3-00007-gaf5a2cb1ad5c-dirty #11 Hardware name: ARM-Versatile Express [<c0013fa5>] (unwind_backtrace) from [<c001084d>] (show_stack+0x11/0x14) [<c001084d>] (show_stack) from [<c04fe7f1>] (dump_stack+0x6d/0x78) [<c04fe7f1>] (dump_stack) from [<c0020645>] (warn_slowpath_common+0x69/0x90) [<c0020645>] (warn_slowpath_common) from [<c00206db>] (warn_slowpath_null+0x17/0x1c) [<c00206db>] (warn_slowpath_null) from [<c001cbdd>] (mcpm_cpu_suspend+0x6d/0x74) [<c001cbdd>] (mcpm_cpu_suspend) from [<c03c6919>] (bl_powerdown_finisher+0x21/0x24) [<c03c6919>] (bl_powerdown_finisher) from [<c001218d>] (cpu_suspend_abort+0x1/0x14) [<c001218d>] (cpu_suspend_abort) from [<00000000>] ( (null)) ---[ end trace d098e3fd00000008 ]--- This patch fixes the issue by checking for the availability of MCPM before initializing the big.LITTLE cpuidle driver Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> --- drivers/cpuidle/cpuidle-big_little.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c index e3e225fe6b45..40c34faffe59 100644 --- a/drivers/cpuidle/cpuidle-big_little.c +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -182,6 +182,10 @@ static int __init bl_idle_init(void) */ if (!of_match_node(compatible_machine_match, root)) return -ENODEV; + + if (!mcpm_is_available()) + return -EUNATCH; + /* * For now the differentiation between little and big cores * is based on the part number. A7 cores are considered little -- 1.9.1
next reply other threads:[~2015-01-08 6:29 UTC|newest] Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-01-08 6:29 Sudeep Holla [this message] 2015-01-08 6:29 ` [PATCH] drivers: cpuidle: don't initialize big.LITTLE driver if MCPM is unavailable Sudeep Holla 2015-01-08 8:53 ` Daniel Lezcano 2015-01-08 8:53 ` Daniel Lezcano 2015-01-08 9:16 ` Sudeep Holla 2015-01-08 9:16 ` Sudeep Holla 2015-01-08 10:02 ` Daniel Lezcano 2015-01-08 10:02 ` Daniel Lezcano 2015-01-08 10:31 ` Sudeep Holla 2015-01-08 10:31 ` Sudeep Holla 2015-01-08 11:11 ` Daniel Lezcano 2015-01-08 11:11 ` Daniel Lezcano 2015-01-08 12:29 ` Lorenzo Pieralisi 2015-01-08 12:29 ` Lorenzo Pieralisi 2015-01-08 14:01 ` Daniel Lezcano 2015-01-08 14:01 ` Daniel Lezcano 2015-01-08 14:46 ` Lorenzo Pieralisi 2015-01-08 14:46 ` Lorenzo Pieralisi 2015-01-08 20:27 ` Kevin Hilman 2015-01-08 20:27 ` Kevin Hilman 2015-01-08 20:51 ` Daniel Lezcano 2015-01-08 20:51 ` Daniel Lezcano 2015-01-09 17:34 ` Kevin Hilman 2015-01-09 17:34 ` Kevin Hilman 2015-01-09 4:58 ` Sudeep Holla 2015-01-09 4:58 ` Sudeep Holla 2015-01-09 5:01 ` Sudeep Holla 2015-01-09 5:01 ` Sudeep Holla 2015-01-25 14:39 [GIT PULL] : cpuidle-big.little fix when mcpm is not available Daniel Lezcano 2015-01-25 20:53 ` [PATCH] drivers: cpuidle: Don't initialize big.LITTLE driver if MCPM is unavailable Daniel Lezcano
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