We need different orderings when turning a core on and turning a core
off. In one case we need to assert reset before turning power off.
In ther other case we need to turn power on and the deassert reset.
In general, the correct flow is:
CPU off:
reset_control_assert
regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), BIT(pd))
ensure power domain is on
CPU on:
regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), 0)
reset_control_deassert
ensure power domain is on
This is needed for stressing CPU up/down, as per:
cd /sys/devices/system/cpu/
for i in $(seq 1000); do
echo "================= $i ============"
for j in $(seq 100); do
while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)"
!= "000"" ]]
echo 0 > cpu1/online
echo 0 > cpu2/online
echo 0 > cpu3/online
done
while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)"
!= "111" ]]; do
echo 1 > cpu1/online
echo 1 > cpu2/online
echo 1 > cpu3/online
done
done
done
The following is reproducile log:
[34466.186812] PM: noirq suspend of devices complete after 0.669 msecs
[34466.186824] Disabling non-boot CPUs ...
[34466.187509] CPU1: shutdown
[34466.188672] CPU2: shutdown
[34473.736627] Kernel panic - not syncing:Watchdog detected hard LOCKUP on
cpu 0
.......
Signed-off-by: Caesar Wang <w...@rock-chips.com>
Reviewed-by: Doug Anderson <diand...@chromium.org>
---
arch/arm/mach-rockchip/platsmp.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)
diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
index 5b4ca3c..a297b86 100644
--- a/arch/arm/mach-rockchip/platsmp.c
+++ b/arch/arm/mach-rockchip/platsmp.c
@@ -88,18 +88,26 @@ static int pmu_set_power_domain(int pd, bool on)
return PTR_ERR(rstc);
}
+ if (!on)
+ reset_control_assert(rstc);
+
+ ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
+ if (ret < 0) {
+ pr_err("%s: could not update power domain\n", __func__);
+ reset_control_put(rstc);
+ return ret;
+ }
+
if (on)
reset_control_deassert(rstc);
- else
- reset_control_assert(rstc);
reset_control_put(rstc);
- }
-
- ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
- if (ret < 0) {
- pr_err("%s: could not update power domain\n", __func__);
- return ret;
+ } else {
+ ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
+ if (ret < 0) {
+ pr_err("%s: could not update power domain\n", __func__);
+ return ret;
+ }
}
ret = -1;
--
1.9.1
--
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