* [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
@ 2018-05-22 21:14 Dmitry Osipenko
2018-05-23 5:58 ` Viresh Kumar
0 siblings, 1 reply; 7+ messages in thread
From: Dmitry Osipenko @ 2018-05-22 21:14 UTC (permalink / raw)
To: Rafael J. Wysocki, Viresh Kumar, Thierry Reding, Jonathan Hunter
Cc: linux-tegra, linux-pm, linux-kernel
Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
on the driver probe.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
CPUFreq maintainers,
Please take into account that this patch is made on top of my recent
series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
reviewed, but seems not applied yet. Let me know if you prefer to re-spin
the [0], including this patch into the series.
[0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
drivers/cpufreq/tegra20-cpufreq.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/drivers/cpufreq/tegra20-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
index 05f57dcd5215..ca5229265b60 100644
--- a/drivers/cpufreq/tegra20-cpufreq.c
+++ b/drivers/cpufreq/tegra20-cpufreq.c
@@ -176,6 +176,14 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
goto put_pll_x;
}
+ err = clk_prepare_enable(cpufreq->pll_x_clk);
+ if (err)
+ goto put_pll_p;
+
+ err = clk_prepare_enable(cpufreq->pll_p_clk);
+ if (err)
+ goto disable_pll_x;
+
cpufreq->dev = &pdev->dev;
cpufreq->driver.get = cpufreq_generic_get;
cpufreq->driver.attr = cpufreq_generic_attr;
@@ -192,12 +200,16 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
err = cpufreq_register_driver(&cpufreq->driver);
if (err)
- goto put_pll_p;
+ goto disable_pll_p;
platform_set_drvdata(pdev, cpufreq);
return 0;
+disable_pll_p:
+ clk_disable_unprepare(cpufreq->pll_p_clk);
+disable_pll_x:
+ clk_disable_unprepare(cpufreq->pll_x_clk);
put_pll_p:
clk_put(cpufreq->pll_p_clk);
put_pll_x:
@@ -214,6 +226,8 @@ static int tegra20_cpufreq_remove(struct platform_device *pdev)
cpufreq_unregister_driver(&cpufreq->driver);
+ clk_disable_unprepare(cpufreq->pll_p_clk);
+ clk_disable_unprepare(cpufreq->pll_x_clk);
clk_put(cpufreq->pll_p_clk);
clk_put(cpufreq->pll_x_clk);
clk_put(cpufreq->cpu_clk);
--
2.17.0
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-22 21:14 [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count Dmitry Osipenko
@ 2018-05-23 5:58 ` Viresh Kumar
2018-05-23 9:30 ` Dmitry Osipenko
2018-05-23 10:44 ` Dmitry Osipenko
0 siblings, 2 replies; 7+ messages in thread
From: Viresh Kumar @ 2018-05-23 5:58 UTC (permalink / raw)
To: Dmitry Osipenko
Cc: Rafael J. Wysocki, Thierry Reding, Jonathan Hunter, linux-tegra,
linux-pm, linux-kernel
On 23-05-18, 00:14, Dmitry Osipenko wrote:
> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
> on the driver probe.
>
> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> ---
>
> CPUFreq maintainers,
>
> Please take into account that this patch is made on top of my recent
> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
> the [0], including this patch into the series.
>
> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
This is already picked by Rafael and is sitting in pm/bleeding-edge
branch. Should get merged into linux-next in a day or two.
> drivers/cpufreq/tegra20-cpufreq.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/tegra20-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
> index 05f57dcd5215..ca5229265b60 100644
> --- a/drivers/cpufreq/tegra20-cpufreq.c
> +++ b/drivers/cpufreq/tegra20-cpufreq.c
> @@ -176,6 +176,14 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
> goto put_pll_x;
> }
>
> + err = clk_prepare_enable(cpufreq->pll_x_clk);
> + if (err)
> + goto put_pll_p;
> +
> + err = clk_prepare_enable(cpufreq->pll_p_clk);
> + if (err)
> + goto disable_pll_x;
> +
> cpufreq->dev = &pdev->dev;
> cpufreq->driver.get = cpufreq_generic_get;
> cpufreq->driver.attr = cpufreq_generic_attr;
> @@ -192,12 +200,16 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>
> err = cpufreq_register_driver(&cpufreq->driver);
> if (err)
> - goto put_pll_p;
> + goto disable_pll_p;
>
> platform_set_drvdata(pdev, cpufreq);
>
> return 0;
>
> +disable_pll_p:
> + clk_disable_unprepare(cpufreq->pll_p_clk);
> +disable_pll_x:
> + clk_disable_unprepare(cpufreq->pll_x_clk);
> put_pll_p:
> clk_put(cpufreq->pll_p_clk);
> put_pll_x:
> @@ -214,6 +226,8 @@ static int tegra20_cpufreq_remove(struct platform_device *pdev)
>
> cpufreq_unregister_driver(&cpufreq->driver);
>
> + clk_disable_unprepare(cpufreq->pll_p_clk);
> + clk_disable_unprepare(cpufreq->pll_x_clk);
> clk_put(cpufreq->pll_p_clk);
> clk_put(cpufreq->pll_x_clk);
> clk_put(cpufreq->cpu_clk);
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
--
viresh
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-23 5:58 ` Viresh Kumar
@ 2018-05-23 9:30 ` Dmitry Osipenko
2018-05-24 9:36 ` Rafael J. Wysocki
2018-05-23 10:44 ` Dmitry Osipenko
1 sibling, 1 reply; 7+ messages in thread
From: Dmitry Osipenko @ 2018-05-23 9:30 UTC (permalink / raw)
To: Viresh Kumar
Cc: Rafael J. Wysocki, Thierry Reding, Jonathan Hunter, linux-tegra,
linux-pm, linux-kernel
On 23.05.2018 08:58, Viresh Kumar wrote:
> On 23-05-18, 00:14, Dmitry Osipenko wrote:
>> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
>> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
>> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
>> on the driver probe.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>> ---
>>
>> CPUFreq maintainers,
>>
>> Please take into account that this patch is made on top of my recent
>> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
>> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
>> the [0], including this patch into the series.
>>
>> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
>
> This is already picked by Rafael and is sitting in pm/bleeding-edge
> branch. Should get merged into linux-next in a day or two.
Neat, thank you for letting me know.
>> drivers/cpufreq/tegra20-cpufreq.c | 16 +++++++++++++++-
>> 1 file changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/tegra20-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
>> index 05f57dcd5215..ca5229265b60 100644
>> --- a/drivers/cpufreq/tegra20-cpufreq.c
>> +++ b/drivers/cpufreq/tegra20-cpufreq.c
>> @@ -176,6 +176,14 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>> goto put_pll_x;
>> }
>>
>> + err = clk_prepare_enable(cpufreq->pll_x_clk);
>> + if (err)
>> + goto put_pll_p;
>> +
>> + err = clk_prepare_enable(cpufreq->pll_p_clk);
>> + if (err)
>> + goto disable_pll_x;
>> +
>> cpufreq->dev = &pdev->dev;
>> cpufreq->driver.get = cpufreq_generic_get;
>> cpufreq->driver.attr = cpufreq_generic_attr;
>> @@ -192,12 +200,16 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>>
>> err = cpufreq_register_driver(&cpufreq->driver);
>> if (err)
>> - goto put_pll_p;
>> + goto disable_pll_p;
>>
>> platform_set_drvdata(pdev, cpufreq);
>>
>> return 0;
>>
>> +disable_pll_p:
>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>> +disable_pll_x:
>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>> put_pll_p:
>> clk_put(cpufreq->pll_p_clk);
>> put_pll_x:
>> @@ -214,6 +226,8 @@ static int tegra20_cpufreq_remove(struct platform_device *pdev)
>>
>> cpufreq_unregister_driver(&cpufreq->driver);
>>
>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>> clk_put(cpufreq->pll_p_clk);
>> clk_put(cpufreq->pll_x_clk);
>> clk_put(cpufreq->cpu_clk);
>
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-23 5:58 ` Viresh Kumar
2018-05-23 9:30 ` Dmitry Osipenko
@ 2018-05-23 10:44 ` Dmitry Osipenko
2018-05-23 14:46 ` Dmitry Osipenko
1 sibling, 1 reply; 7+ messages in thread
From: Dmitry Osipenko @ 2018-05-23 10:44 UTC (permalink / raw)
To: Viresh Kumar
Cc: Rafael J. Wysocki, Thierry Reding, Jonathan Hunter, linux-tegra,
linux-pm, linux-kernel
On 23.05.2018 08:58, Viresh Kumar wrote:
> On 23-05-18, 00:14, Dmitry Osipenko wrote:
>> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
>> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
>> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
>> on the driver probe.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>> ---
>>
>> CPUFreq maintainers,
>>
>> Please take into account that this patch is made on top of my recent
>> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
>> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
>> the [0], including this patch into the series.
>>
>> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
>
> This is already picked by Rafael and is sitting in pm/bleeding-edge
> branch. Should get merged into linux-next in a day or two.
>
>> drivers/cpufreq/tegra20-cpufreq.c | 16 +++++++++++++++-
>> 1 file changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/tegra20-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
>> index 05f57dcd5215..ca5229265b60 100644
>> --- a/drivers/cpufreq/tegra20-cpufreq.c
>> +++ b/drivers/cpufreq/tegra20-cpufreq.c
>> @@ -176,6 +176,14 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>> goto put_pll_x;
>> }
>>
>> + err = clk_prepare_enable(cpufreq->pll_x_clk);
>> + if (err)
>> + goto put_pll_p;
>> +
>> + err = clk_prepare_enable(cpufreq->pll_p_clk);
>> + if (err)
>> + goto disable_pll_x;
>> +
>> cpufreq->dev = &pdev->dev;
>> cpufreq->driver.get = cpufreq_generic_get;
>> cpufreq->driver.attr = cpufreq_generic_attr;
>> @@ -192,12 +200,16 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>>
>> err = cpufreq_register_driver(&cpufreq->driver);
>> if (err)
>> - goto put_pll_p;
>> + goto disable_pll_p;
>>
>> platform_set_drvdata(pdev, cpufreq);
>>
>> return 0;
>>
>> +disable_pll_p:
>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>> +disable_pll_x:
>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>> put_pll_p:
>> clk_put(cpufreq->pll_p_clk);
>> put_pll_x:
>> @@ -214,6 +226,8 @@ static int tegra20_cpufreq_remove(struct platform_device *pdev)
>>
>> cpufreq_unregister_driver(&cpufreq->driver);
>>
>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>> clk_put(cpufreq->pll_p_clk);
>> clk_put(cpufreq->pll_x_clk);
>> clk_put(cpufreq->cpu_clk);
>
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
>
Please hold on this patch, seems I interpreted the cpufreq driver logic
incorrectly and it is probably fine as it is. I'll re-check later today.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-23 10:44 ` Dmitry Osipenko
@ 2018-05-23 14:46 ` Dmitry Osipenko
0 siblings, 0 replies; 7+ messages in thread
From: Dmitry Osipenko @ 2018-05-23 14:46 UTC (permalink / raw)
To: Viresh Kumar, Rafael J. Wysocki
Cc: Thierry Reding, Jonathan Hunter, linux-tegra, linux-pm, linux-kernel
On 23.05.2018 13:44, Dmitry Osipenko wrote:
> On 23.05.2018 08:58, Viresh Kumar wrote:
>> On 23-05-18, 00:14, Dmitry Osipenko wrote:
>>> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
>>> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
>>> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
>>> on the driver probe.
>>>
>>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>>> ---
>>>
>>> CPUFreq maintainers,
>>>
>>> Please take into account that this patch is made on top of my recent
>>> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
>>> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
>>> the [0], including this patch into the series.
>>>
>>> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
>>
>> This is already picked by Rafael and is sitting in pm/bleeding-edge
>> branch. Should get merged into linux-next in a day or two.
>>
>>> drivers/cpufreq/tegra20-cpufreq.c | 16 +++++++++++++++-
>>> 1 file changed, 15 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/cpufreq/tegra20-cpufreq.c b/drivers/cpufreq/tegra20-cpufreq.c
>>> index 05f57dcd5215..ca5229265b60 100644
>>> --- a/drivers/cpufreq/tegra20-cpufreq.c
>>> +++ b/drivers/cpufreq/tegra20-cpufreq.c
>>> @@ -176,6 +176,14 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>>> goto put_pll_x;
>>> }
>>>
>>> + err = clk_prepare_enable(cpufreq->pll_x_clk);
>>> + if (err)
>>> + goto put_pll_p;
>>> +
>>> + err = clk_prepare_enable(cpufreq->pll_p_clk);
>>> + if (err)
>>> + goto disable_pll_x;
>>> +
>>> cpufreq->dev = &pdev->dev;
>>> cpufreq->driver.get = cpufreq_generic_get;
>>> cpufreq->driver.attr = cpufreq_generic_attr;
>>> @@ -192,12 +200,16 @@ static int tegra20_cpufreq_probe(struct platform_device *pdev)
>>>
>>> err = cpufreq_register_driver(&cpufreq->driver);
>>> if (err)
>>> - goto put_pll_p;
>>> + goto disable_pll_p;
>>>
>>> platform_set_drvdata(pdev, cpufreq);
>>>
>>> return 0;
>>>
>>> +disable_pll_p:
>>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>>> +disable_pll_x:
>>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>>> put_pll_p:
>>> clk_put(cpufreq->pll_p_clk);
>>> put_pll_x:
>>> @@ -214,6 +226,8 @@ static int tegra20_cpufreq_remove(struct platform_device *pdev)
>>>
>>> cpufreq_unregister_driver(&cpufreq->driver);
>>>
>>> + clk_disable_unprepare(cpufreq->pll_p_clk);
>>> + clk_disable_unprepare(cpufreq->pll_x_clk);
>>> clk_put(cpufreq->pll_p_clk);
>>> clk_put(cpufreq->pll_x_clk);
>>> clk_put(cpufreq->cpu_clk);
>>
>> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
>>
>
> Please hold on this patch, seems I interpreted the cpufreq driver logic
> incorrectly and it is probably fine as it is. I'll re-check later today.
>
I've re-checked the driver and it is fine, PLL_X disabling is expected on a
switching parent clock to PLL_P as for the target frequency. This patch isn't
needed, please scratch it.
It occurred to me that the driver could be improved further a tad while I was
performing the re-check, hence likely there will be couple more patches from me.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-23 9:30 ` Dmitry Osipenko
@ 2018-05-24 9:36 ` Rafael J. Wysocki
2018-05-24 12:18 ` Dmitry Osipenko
0 siblings, 1 reply; 7+ messages in thread
From: Rafael J. Wysocki @ 2018-05-24 9:36 UTC (permalink / raw)
To: Dmitry Osipenko
Cc: Viresh Kumar, Thierry Reding, Jonathan Hunter, linux-tegra,
linux-pm, linux-kernel
On Wednesday, May 23, 2018 11:30:39 AM CEST Dmitry Osipenko wrote:
> On 23.05.2018 08:58, Viresh Kumar wrote:
> > On 23-05-18, 00:14, Dmitry Osipenko wrote:
> >> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
> >> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
> >> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
> >> on the driver probe.
> >>
> >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> >> ---
> >>
> >> CPUFreq maintainers,
> >>
> >> Please take into account that this patch is made on top of my recent
> >> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
> >> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
> >> the [0], including this patch into the series.
> >>
> >> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
> >
> > This is already picked by Rafael and is sitting in pm/bleeding-edge
> > branch. Should get merged into linux-next in a day or two.
>
> Neat, thank you for letting me know.
It actually is there in my linux-next branch, but linux-next proper is not
taking new material this week AFAICS.
You'll see this in linux-next on Monday, most probably.
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count
2018-05-24 9:36 ` Rafael J. Wysocki
@ 2018-05-24 12:18 ` Dmitry Osipenko
0 siblings, 0 replies; 7+ messages in thread
From: Dmitry Osipenko @ 2018-05-24 12:18 UTC (permalink / raw)
To: Rafael J. Wysocki
Cc: Viresh Kumar, Thierry Reding, Jonathan Hunter, linux-tegra,
linux-pm, linux-kernel
On 24.05.2018 12:36, Rafael J. Wysocki wrote:
> On Wednesday, May 23, 2018 11:30:39 AM CEST Dmitry Osipenko wrote:
>> On 23.05.2018 08:58, Viresh Kumar wrote:
>>> On 23-05-18, 00:14, Dmitry Osipenko wrote:
>>>> Tegra20-cpufreq driver missed enabling the CPU clocks. This results in a
>>>> clock-enable refcount disbalance on PLL_P <-> PLL_X reparent, causing
>>>> PLL_X to get disabled while it shouldn't. Fix this by enabling the clocks
>>>> on the driver probe.
>>>>
>>>> Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
>>>> ---
>>>>
>>>> CPUFreq maintainers,
>>>>
>>>> Please take into account that this patch is made on top of my recent
>>>> series of patches [0] "Clean up Tegra20 cpufreq driver" that was fully
>>>> reviewed, but seems not applied yet. Let me know if you prefer to re-spin
>>>> the [0], including this patch into the series.
>>>>
>>>> [0] https://patchwork.ozlabs.org/project/linux-tegra/list/?series=45321
>>>
>>> This is already picked by Rafael and is sitting in pm/bleeding-edge
>>> branch. Should get merged into linux-next in a day or two.
>>
>> Neat, thank you for letting me know.
>
> It actually is there in my linux-next branch, but linux-next proper is not
> taking new material this week AFAICS.
I've found it in yours git repo, thank you.
> You'll see this in linux-next on Monday, most probably.
>
Yes, I noticed that linux-next stopped updating for awhile.
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2018-05-24 12:18 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-05-22 21:14 [PATCH v1] cpufreq: tegra20: Fix imbalanced clock enable count Dmitry Osipenko
2018-05-23 5:58 ` Viresh Kumar
2018-05-23 9:30 ` Dmitry Osipenko
2018-05-24 9:36 ` Rafael J. Wysocki
2018-05-24 12:18 ` Dmitry Osipenko
2018-05-23 10:44 ` Dmitry Osipenko
2018-05-23 14:46 ` Dmitry Osipenko
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