[PATCH v2 1/9] ARM: EXYNOS: cpuidle: fix AFTR mode check

From: Bartlomiej Zolnierkiewicz
Date: Fri Dec 20 2013 - 13:48:09 EST


The EXYNOS cpuidle driver code assumes that cpuidle core will handle
dev->state_count smaller than drv->state_count but currently this is
untrue (dev->state_count is used only for handling cpuidle state sysfs
entries and drv->state_count is used for all other cases) and will not
be fixed in the future as dev->state_count is planned to be removed.

Fix the issue by checking for the max supported idle state in AFTR
state's ->enter handler (exynos4_enter_lowpower()) and entering AFTR
mode only when cores other than CPU0 are offline.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
Cc: Kukjin Kim <kgene.kim@xxxxxxxxxxx>
---
arch/arm/mach-exynos/cpuidle.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-exynos/cpuidle.c b/arch/arm/mach-exynos/cpuidle.c
index da65b03..f57cb91 100644
--- a/arch/arm/mach-exynos/cpuidle.c
+++ b/arch/arm/mach-exynos/cpuidle.c
@@ -172,8 +172,8 @@ static int exynos4_enter_lowpower(struct cpuidle_device *dev,
{
int new_index = index;

- /* This mode only can be entered when other core's are offline */
- if (num_online_cpus() > 1)
+ /* AFTR can only be entered when cores other than CPU0 are offline */
+ if (num_online_cpus() > 1 || dev->cpu != 0)
new_index = drv->safe_state_index;

if (new_index == 0)
@@ -235,10 +235,6 @@ static int exynos_cpuidle_probe(struct platform_device *pdev)
device = &per_cpu(exynos4_cpuidle_device, cpu_id);
device->cpu = cpu_id;

- /* Support IDLE only */
- if (cpu_id != 0)
- device->state_count = 1;
-
ret = cpuidle_register_device(device);
if (ret) {
dev_err(&pdev->dev, "failed to register cpuidle device\n");
--
1.8.2.3

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