2020-05-14 07:39:30

by Tero Kristo

Subject: [PATCH 1/1] soc: ti: omap-prm: use atomic iopoll instead of sleeping one

The reset handling APIs for omap-prm can be invoked PM runtime which
runs in atomic context. For this to work properly, switch to atomic
iopoll version instead of the current which can sleep. Otherwise,
this throws a "BUG: scheduling while atomic" warning. Issue is seen
rather easily when CONFIG_PREEMPT is enabled.

Signed-off-by: Tero Kristo <[email protected]>
---
drivers/soc/ti/omap_prm.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
index 96c6f777519c..c9b3f9ebf0bb 100644
--- a/drivers/soc/ti/omap_prm.c
+++ b/drivers/soc/ti/omap_prm.c
@@ -256,10 +256,10 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
goto exit;

/* wait for the status to be set */
- ret = readl_relaxed_poll_timeout(reset->prm->base +
- reset->prm->data->rstst,
- v, v & BIT(st_bit), 1,
- OMAP_RESET_MAX_WAIT);
+ ret = readl_relaxed_poll_timeout_atomic(reset->prm->base +
+ reset->prm->data->rstst,
+ v, v & BIT(st_bit), 1,
+ OMAP_RESET_MAX_WAIT);
if (ret)
pr_err("%s: timedout waiting for %s:%lu\n", __func__,
reset->prm->data->name, id);
--
2.17.1

--
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

2020-05-19 17:50:41

by Tony Lindgren

Subject: Re: [PATCH 1/1] soc: ti: omap-prm: use atomic iopoll instead of sleeping one

* Tero Kristo <[email protected]> [200514 00:38]:
> The reset handling APIs for omap-prm can be invoked PM runtime which
> runs in atomic context. For this to work properly, switch to atomic
> iopoll version instead of the current which can sleep. Otherwise,
> this throws a "BUG: scheduling while atomic" warning. Issue is seen
> rather easily when CONFIG_PREEMPT is enabled.
>
> Signed-off-by: Tero Kristo <[email protected]>

Santosh do you want me to pick this for fixes?

Regards,

Tony

> ---
> drivers/soc/ti/omap_prm.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c
> index 96c6f777519c..c9b3f9ebf0bb 100644
> --- a/drivers/soc/ti/omap_prm.c
> +++ b/drivers/soc/ti/omap_prm.c
> @@ -256,10 +256,10 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
> goto exit;
>
> /* wait for the status to be set */
> - ret = readl_relaxed_poll_timeout(reset->prm->base +
> - reset->prm->data->rstst,
> - v, v & BIT(st_bit), 1,
> - OMAP_RESET_MAX_WAIT);
> + ret = readl_relaxed_poll_timeout_atomic(reset->prm->base +
> + reset->prm->data->rstst,
> + v, v & BIT(st_bit), 1,
> + OMAP_RESET_MAX_WAIT);
> if (ret)
> pr_err("%s: timedout waiting for %s:%lu\n", __func__,
> reset->prm->data->name, id);
> --
> 2.17.1
>
> --
> Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>

2020-05-19 18:06:43

by Santosh Shilimkar

Subject: Re: [PATCH 1/1] soc: ti: omap-prm: use atomic iopoll instead of sleeping one

On 5/19/20 10:45 AM, Tony Lindgren wrote:
> * Tero Kristo <[email protected]> [200514 00:38]:
>> The reset handling APIs for omap-prm can be invoked PM runtime which
>> runs in atomic context. For this to work properly, switch to atomic
>> iopoll version instead of the current which can sleep. Otherwise,
>> this throws a "BUG: scheduling while atomic" warning. Issue is seen
>> rather easily when CONFIG_PREEMPT is enabled.
>>
>> Signed-off-by: Tero Kristo <[email protected]>
>
> Santosh do you want me to pick this for fixes?
>
Sure Tony. Thanks !!

Acked-by: Santosh Shilimkar <[email protected]>