* [PATCH] media: fdp1: Reduce FCP not found message level to debug
@ 2019-07-09 9:59 Geert Uytterhoeven
2019-07-09 10:07 ` Kieran Bingham
0 siblings, 1 reply; 5+ messages in thread
From: Geert Uytterhoeven @ 2019-07-09 9:59 UTC (permalink / raw)
To: Kieran Bingham, Laurent Pinchart, Mauro Carvalho Chehab
Cc: linux-media, linux-renesas-soc, Geert Uytterhoeven
When support for the IPMMU is not enabled, the FDP driver may be
probe-deferred multiple times, causing several messages to be printed
like:
rcar_fdp1 fe940000.fdp1: FCP not found (-517)
rcar_fdp1 fe944000.fdp1: FCP not found (-517)
Fix this by reducing the message level to debug level, as is done in the
VSP1 driver.
Fixes: 4710b752e029f3f8 ("[media] v4l: Add Renesas R-Car FDP1 Driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
The alternative would be to add an explicit check for -EPROBE_DEFER.
---
drivers/media/platform/rcar_fdp1.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/media/platform/rcar_fdp1.c b/drivers/media/platform/rcar_fdp1.c
index 43aae9b6bb20e3e8..c23ec127c2776f51 100644
--- a/drivers/media/platform/rcar_fdp1.c
+++ b/drivers/media/platform/rcar_fdp1.c
@@ -2306,7 +2306,7 @@ static int fdp1_probe(struct platform_device *pdev)
fdp1->fcp = rcar_fcp_get(fcp_node);
of_node_put(fcp_node);
if (IS_ERR(fdp1->fcp)) {
- dev_err(&pdev->dev, "FCP not found (%ld)\n",
+ dev_dbg(&pdev->dev, "FCP not found (%ld)\n",
PTR_ERR(fdp1->fcp));
return PTR_ERR(fdp1->fcp);
}
--
2.17.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH] media: fdp1: Reduce FCP not found message level to debug
2019-07-09 9:59 [PATCH] media: fdp1: Reduce FCP not found message level to debug Geert Uytterhoeven
@ 2019-07-09 10:07 ` Kieran Bingham
2019-07-09 10:13 ` Geert Uytterhoeven
0 siblings, 1 reply; 5+ messages in thread
From: Kieran Bingham @ 2019-07-09 10:07 UTC (permalink / raw)
To: Geert Uytterhoeven, Laurent Pinchart, Mauro Carvalho Chehab
Cc: linux-media, linux-renesas-soc
Hi Geert,
On 09/07/2019 10:59, Geert Uytterhoeven wrote:
> When support for the IPMMU is not enabled, the FDP driver may be
> probe-deferred multiple times, causing several messages to be printed
> like:
>
> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
>
> Fix this by reducing the message level to debug level, as is done in the
> VSP1 driver.
Does the lack of IPMMU prevent the FDP1 being loaded entirely?
If so is that a problem for us? (I thought we were able to run without
the IPMMU)
> Fixes: 4710b752e029f3f8 ("[media] v4l: Add Renesas R-Car FDP1 Driver")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> The alternative would be to add an explicit check for -EPROBE_DEFER.
> ---
> drivers/media/platform/rcar_fdp1.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/rcar_fdp1.c b/drivers/media/platform/rcar_fdp1.c
> index 43aae9b6bb20e3e8..c23ec127c2776f51 100644
> --- a/drivers/media/platform/rcar_fdp1.c
> +++ b/drivers/media/platform/rcar_fdp1.c
> @@ -2306,7 +2306,7 @@ static int fdp1_probe(struct platform_device *pdev)
> fdp1->fcp = rcar_fcp_get(fcp_node);
> of_node_put(fcp_node);
> if (IS_ERR(fdp1->fcp)) {
> - dev_err(&pdev->dev, "FCP not found (%ld)\n",
> + dev_dbg(&pdev->dev, "FCP not found (%ld)\n",
> PTR_ERR(fdp1->fcp));
Should we be doing something differently here in the event of no IPMMU then?
Otherwise, if the IPMMU has become a hard dependency, should we add it
to the Kconfig dependencies?
> return PTR_ERR(fdp1->fcp);
> }
>
--
Regards
Kieran
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] media: fdp1: Reduce FCP not found message level to debug
2019-07-09 10:07 ` Kieran Bingham
@ 2019-07-09 10:13 ` Geert Uytterhoeven
2019-07-09 10:18 ` Kieran Bingham
0 siblings, 1 reply; 5+ messages in thread
From: Geert Uytterhoeven @ 2019-07-09 10:13 UTC (permalink / raw)
To: Kieran Bingham
Cc: Geert Uytterhoeven, Laurent Pinchart, Mauro Carvalho Chehab,
Linux Media Mailing List, Linux-Renesas
Hi Kieran,
On Tue, Jul 9, 2019 at 12:07 PM Kieran Bingham
<kieran.bingham+renesas@ideasonboard.com> wrote:
> On 09/07/2019 10:59, Geert Uytterhoeven wrote:
> > When support for the IPMMU is not enabled, the FDP driver may be
> > probe-deferred multiple times, causing several messages to be printed
> > like:
> >
> > rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> >
> > Fix this by reducing the message level to debug level, as is done in the
> > VSP1 driver.
>
> Does the lack of IPMMU prevent the FDP1 being loaded entirely?
No it doesn't.
If CONFIG_IPMMU_VMSA=n,
rcar_fdp1 fe940000.fdp1: FCP not found (-517)
rcar_fdp1 fe944000.fdp1: FCP not found (-517)
rcar_fdp1 fe940000.fdp1: FCP not found (-517)
rcar_fdp1 fe944000.fdp1: FCP not found (-517)
rcar_fdp1 fe940000.fdp1: FCP not found (-517)
rcar_fdp1 fe944000.fdp1: FCP not found (-517)
rcar_fdp1 fe940000.fdp1: Device registered as /dev/video8
rcar_fdp1 fe944000.fdp1: Device registered as /dev/video9
So the driver succeeds, eventually.
If CONFIG_IPMMU_VMSA=y, it succeeds sooner:
rcar_fdp1 fe940000.fdp1: Device registered as /dev/video0
rcar_fdp1 fe944000.fdp1: Device registered as /dev/video1
Always be prepared to handle -EPROBE_DEFER.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] media: fdp1: Reduce FCP not found message level to debug
2019-07-09 10:13 ` Geert Uytterhoeven
@ 2019-07-09 10:18 ` Kieran Bingham
2019-07-09 10:28 ` Geert Uytterhoeven
0 siblings, 1 reply; 5+ messages in thread
From: Kieran Bingham @ 2019-07-09 10:18 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Geert Uytterhoeven, Laurent Pinchart, Mauro Carvalho Chehab,
Linux Media Mailing List, Linux-Renesas
Hi Geert,
On 09/07/2019 11:13, Geert Uytterhoeven wrote:
> Hi Kieran,
>
> On Tue, Jul 9, 2019 at 12:07 PM Kieran Bingham
> <kieran.bingham+renesas@ideasonboard.com> wrote:
>> On 09/07/2019 10:59, Geert Uytterhoeven wrote:
>>> When support for the IPMMU is not enabled, the FDP driver may be
>>> probe-deferred multiple times, causing several messages to be printed
>>> like:
>>>
>>> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
>>> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
>>>
>>> Fix this by reducing the message level to debug level, as is done in the
>>> VSP1 driver.
>>
>> Does the lack of IPMMU prevent the FDP1 being loaded entirely?
>
> No it doesn't.
> If CONFIG_IPMMU_VMSA=n,
>
> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> rcar_fdp1 fe940000.fdp1: Device registered as /dev/video8
> rcar_fdp1 fe944000.fdp1: Device registered as /dev/video9
>
> So the driver succeeds, eventually.
>
> If CONFIG_IPMMU_VMSA=y, it succeeds sooner:
>
> rcar_fdp1 fe940000.fdp1: Device registered as /dev/video0
> rcar_fdp1 fe944000.fdp1: Device registered as /dev/video1
>
> Always be prepared to handle -EPROBE_DEFER.
>
> Gr{oetje,eeting}s,
On the basis that the driver is not prevented from loading, then the
message does indeed become more of a debug print.
I wonder if it's better to print something different in the event of
EPROBE_DEFER vs another actual error preventing the loading of the
driver, but in either case if someone hits an issue they're likely to
start adding/enabling debug.
So, with that and a precedent for this change in VSP1, I'm happy here.
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
>
> Geert
>
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] media: fdp1: Reduce FCP not found message level to debug
2019-07-09 10:18 ` Kieran Bingham
@ 2019-07-09 10:28 ` Geert Uytterhoeven
0 siblings, 0 replies; 5+ messages in thread
From: Geert Uytterhoeven @ 2019-07-09 10:28 UTC (permalink / raw)
To: Kieran Bingham
Cc: Geert Uytterhoeven, Laurent Pinchart, Mauro Carvalho Chehab,
Linux Media Mailing List, Linux-Renesas
Hi Kieran,
On Tue, Jul 9, 2019 at 12:18 PM Kieran Bingham
<kieran.bingham+renesas@ideasonboard.com> wrote:
> On 09/07/2019 11:13, Geert Uytterhoeven wrote:
> > On Tue, Jul 9, 2019 at 12:07 PM Kieran Bingham
> > <kieran.bingham+renesas@ideasonboard.com> wrote:
> >> On 09/07/2019 10:59, Geert Uytterhoeven wrote:
> >>> When support for the IPMMU is not enabled, the FDP driver may be
> >>> probe-deferred multiple times, causing several messages to be printed
> >>> like:
> >>>
> >>> rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> >>> rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> >>>
> >>> Fix this by reducing the message level to debug level, as is done in the
> >>> VSP1 driver.
> >>
> >> Does the lack of IPMMU prevent the FDP1 being loaded entirely?
> >
> > No it doesn't.
> > If CONFIG_IPMMU_VMSA=n,
> >
> > rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe940000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe944000.fdp1: FCP not found (-517)
> > rcar_fdp1 fe940000.fdp1: Device registered as /dev/video8
> > rcar_fdp1 fe944000.fdp1: Device registered as /dev/video9
> >
> > So the driver succeeds, eventually.
> >
> > If CONFIG_IPMMU_VMSA=y, it succeeds sooner:
> >
> > rcar_fdp1 fe940000.fdp1: Device registered as /dev/video0
> > rcar_fdp1 fe944000.fdp1: Device registered as /dev/video1
> >
> > Always be prepared to handle -EPROBE_DEFER.
>
> On the basis that the driver is not prevented from loading, then the
> message does indeed become more of a debug print.
>
> I wonder if it's better to print something different in the event of
> EPROBE_DEFER vs another actual error preventing the loading of the
> driver, but in either case if someone hits an issue they're likely to
> start adding/enabling debug.
That's why some driver suppress printing errors for -EPROBE_DEFER.
> So, with that and a precedent for this change in VSP1, I'm happy here.
>
> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply [flat|nested] 5+ messages in thread
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2019-07-09 9:59 [PATCH] media: fdp1: Reduce FCP not found message level to debug Geert Uytterhoeven
2019-07-09 10:07 ` Kieran Bingham
2019-07-09 10:13 ` Geert Uytterhoeven
2019-07-09 10:18 ` Kieran Bingham
2019-07-09 10:28 ` Geert Uytterhoeven
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