2015-11-13 10:30:21

by H. Nikolaus Schaller

[permalink] [raw]
Subject: [PATCH 0/2] Fix omap VENC (PAL/NTSC TV out) operation with omapdrm driver

This patch set fixes some issues with the OMAP VENC
when used with the omapdrm driver.

Tested on: BeagleBoard XM, GTA04 and OpenPandora


H. Nikolaus Schaller (2):
video:omap2:dss: fix timings for VENC to match what omapdrm expects
video:omapdrm: make omapdrm assume the tv-out cable is always
connected

drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
drivers/video/fbdev/omap2/dss/venc.c | 12 ++++++++++++
2 files changed, 13 insertions(+)

--
2.5.1


2015-11-13 10:29:25

by H. Nikolaus Schaller

[permalink] [raw]
Subject: [PATCH 1/2] video:omap2:dss: fix timings for VENC to match what omapdrm expects

Otherwise check_timings fails and we get a "has no modes" message
from xrandr.

This fix makes the venc assume PAL and NTSC timings that match the
timings synthetized by copy_timings_drm_to_omap() from omapdrm
mode settings so that check_timings() succeeds.

Tested on: BeagleBoard XM, GTA04 and OpenPandora

Signed-off-by: H. Nikolaus Schaller <[email protected]>
---
drivers/video/fbdev/omap2/dss/venc.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/drivers/video/fbdev/omap2/dss/venc.c b/drivers/video/fbdev/omap2/dss/venc.c
index 99ca268..d05a549 100644
--- a/drivers/video/fbdev/omap2/dss/venc.c
+++ b/drivers/video/fbdev/omap2/dss/venc.c
@@ -275,6 +275,12 @@ const struct omap_video_timings omap_dss_pal_timings = {
.vbp = 41,

.interlace = true,
+
+ .hsync_level = OMAPDSS_SIG_ACTIVE_LOW,
+ .vsync_level = OMAPDSS_SIG_ACTIVE_LOW,
+ .data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE,
+ .de_level = OMAPDSS_SIG_ACTIVE_HIGH,
+ .sync_pclk_edge = OMAPDSS_DRIVE_SIG_FALLING_EDGE,
};
EXPORT_SYMBOL(omap_dss_pal_timings);

@@ -290,6 +296,12 @@ const struct omap_video_timings omap_dss_ntsc_timings = {
.vbp = 31,

.interlace = true,
+
+ .hsync_level = OMAPDSS_SIG_ACTIVE_LOW,
+ .vsync_level = OMAPDSS_SIG_ACTIVE_LOW,
+ .data_pclk_edge = OMAPDSS_DRIVE_SIG_RISING_EDGE,
+ .de_level = OMAPDSS_SIG_ACTIVE_HIGH,
+ .sync_pclk_edge = OMAPDSS_DRIVE_SIG_FALLING_EDGE,
};
EXPORT_SYMBOL(omap_dss_ntsc_timings);

--
2.5.1

2015-11-13 10:30:19

by H. Nikolaus Schaller

[permalink] [raw]
Subject: [PATCH 2/2] video:omapdrm: make omapdrm assume the tv-out cable is always connected

Include VENC in the set of drivers where it is assimed that the cable
is always connected. Like DPI, DSI, DBI and SDI do.

Otherwise, the VENC will return cable status "unknown" and is not enabled
by the X-server. So there is no video output signal.

Tested on: BeagleBoard XM, GTA04 and OpenPandora

Signed-off-by: H. Nikolaus Schaller <[email protected]>
---
drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c b/drivers/gpu/drm/omapdrm/omap_connector.c
index 83f2a91..98ddb5d 100644
--- a/drivers/gpu/drm/omapdrm/omap_connector.c
+++ b/drivers/gpu/drm/omapdrm/omap_connector.c
@@ -120,6 +120,7 @@ static enum drm_connector_status omap_connector_detect(
else
ret = connector_status_disconnected;
} else if (dssdev->type == OMAP_DISPLAY_TYPE_DPI ||
+ dssdev->type == OMAP_DISPLAY_TYPE_VENC ||
dssdev->type == OMAP_DISPLAY_TYPE_DBI ||
dssdev->type == OMAP_DISPLAY_TYPE_SDI ||
dssdev->type == OMAP_DISPLAY_TYPE_DSI) {
--
2.5.1

2015-11-13 11:46:29

by Tomi Valkeinen

[permalink] [raw]
Subject: Re: [PATCH 2/2] video:omapdrm: make omapdrm assume the tv-out cable is always connected



On 13/11/15 12:29, H. Nikolaus Schaller wrote:
> Include VENC in the set of drivers where it is assimed that the cable
> is always connected. Like DPI, DSI, DBI and SDI do.
>
> Otherwise, the VENC will return cable status "unknown" and is not enabled
> by the X-server. So there is no video output signal.
>
> Tested on: BeagleBoard XM, GTA04 and OpenPandora
>
> Signed-off-by: H. Nikolaus Schaller <[email protected]>
> ---
> drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c b/drivers/gpu/drm/omapdrm/omap_connector.c
> index 83f2a91..98ddb5d 100644
> --- a/drivers/gpu/drm/omapdrm/omap_connector.c
> +++ b/drivers/gpu/drm/omapdrm/omap_connector.c
> @@ -120,6 +120,7 @@ static enum drm_connector_status omap_connector_detect(
> else
> ret = connector_status_disconnected;
> } else if (dssdev->type == OMAP_DISPLAY_TYPE_DPI ||
> + dssdev->type == OMAP_DISPLAY_TYPE_VENC ||
> dssdev->type == OMAP_DISPLAY_TYPE_DBI ||
> dssdev->type == OMAP_DISPLAY_TYPE_SDI ||
> dssdev->type == OMAP_DISPLAY_TYPE_DSI) {
>

I have no idea why VENC is not working for you when using
connector_status_unknown, but I just tested DPI with
connector_status_unknown (i.e. changed the above func to return unknown
for DPI), and it works fine with X and X omap driver. And xrandr
confirms that the connection status is unknown:

# xrandr
Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 2048 x 2048
HDMI-1 disconnected (normal left inverted right x axis y axis)
None-1 unknown connection 1920x1200+0+0 (normal left inverted right x
axis y axis) 0mm x 0mm
1920x1200 60.00*+ 60.00 +

Grep also shows that there are many drivers using
connector_status_unknown, so I'm guessing it should work fine...

Tomi


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2015-11-13 12:00:57

by Laurent Pinchart

[permalink] [raw]
Subject: Re: [PATCH 2/2] video:omapdrm: make omapdrm assume the tv-out cable is always connected

On Friday 13 November 2015 13:46:01 Tomi Valkeinen wrote:
> On 13/11/15 12:29, H. Nikolaus Schaller wrote:
> > Include VENC in the set of drivers where it is assimed that the cable
> > is always connected. Like DPI, DSI, DBI and SDI do.
> >
> > Otherwise, the VENC will return cable status "unknown" and is not enabled
> > by the X-server. So there is no video output signal.
> >
> > Tested on: BeagleBoard XM, GTA04 and OpenPandora
> >
> > Signed-off-by: H. Nikolaus Schaller <[email protected]>
> > ---
> >
> > drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
> > 1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c
> > b/drivers/gpu/drm/omapdrm/omap_connector.c index 83f2a91..98ddb5d 100644
> > --- a/drivers/gpu/drm/omapdrm/omap_connector.c
> > +++ b/drivers/gpu/drm/omapdrm/omap_connector.c
> > @@ -120,6 +120,7 @@ static enum drm_connector_status
> > omap_connector_detect(
> > else
> > ret = connector_status_disconnected;
> > } else if (dssdev->type == OMAP_DISPLAY_TYPE_DPI ||
> > + dssdev->type == OMAP_DISPLAY_TYPE_VENC ||
> > dssdev->type == OMAP_DISPLAY_TYPE_DBI ||
> > dssdev->type == OMAP_DISPLAY_TYPE_SDI ||
> > dssdev->type == OMAP_DISPLAY_TYPE_DSI) {
>
> I have no idea why VENC is not working for you when using
> connector_status_unknown, but I just tested DPI with
> connector_status_unknown (i.e. changed the above func to return unknown
> for DPI), and it works fine with X and X omap driver. And xrandr
> confirms that the connection status is unknown:
>
> # xrandr
> Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 2048 x 2048
> HDMI-1 disconnected (normal left inverted right x axis y axis)
> None-1 unknown connection 1920x1200+0+0 (normal left inverted right x
> axis y axis) 0mm x 0mm
> 1920x1200 60.00*+ 60.00 +
>
> Grep also shows that there are many drivers using
> connector_status_unknown, so I'm guessing it should work fine...

And beside it's not right to consider VENC as always connected, as it isn't.
The unknown status is there for a reason, to describe connectors for which we
can't get any status information. The situation is different for DPI, DBI, SDI
and DSI as those are on-board busses that connect to a non-removable panel, so
we can say with a good confidence that the panel is connected (the situation
could be changed with a hammer and a chisel, but that's unlikely to happen,
hence the confidence).

--
Regards,

Laurent Pinchart

2015-11-13 13:32:06

by H. Nikolaus Schaller

[permalink] [raw]
Subject: Re: [PATCH 2/2] video:omapdrm: make omapdrm assume the tv-out cable is always connected

Hi Laurent and Tomi,

Am 13.11.2015 um 13:01 schrieb Laurent Pinchart <[email protected]>:

> On Friday 13 November 2015 13:46:01 Tomi Valkeinen wrote:
>> On 13/11/15 12:29, H. Nikolaus Schaller wrote:
>>> Include VENC in the set of drivers where it is assimed that the cable
>>> is always connected. Like DPI, DSI, DBI and SDI do.
>>>
>>> Otherwise, the VENC will return cable status "unknown" and is not enabled
>>> by the X-server. So there is no video output signal.
>>>
>>> Tested on: BeagleBoard XM, GTA04 and OpenPandora
>>>
>>> Signed-off-by: H. Nikolaus Schaller <[email protected]>
>>> ---
>>>
>>> drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c
>>> b/drivers/gpu/drm/omapdrm/omap_connector.c index 83f2a91..98ddb5d 100644
>>> --- a/drivers/gpu/drm/omapdrm/omap_connector.c
>>> +++ b/drivers/gpu/drm/omapdrm/omap_connector.c
>>> @@ -120,6 +120,7 @@ static enum drm_connector_status
>>> omap_connector_detect(
>>> else
>>> ret = connector_status_disconnected;
>>> } else if (dssdev->type == OMAP_DISPLAY_TYPE_DPI ||
>>> + dssdev->type == OMAP_DISPLAY_TYPE_VENC ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_DBI ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_SDI ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_DSI) {
>>
>> I have no idea why VENC is not working for you when using
>> connector_status_unknown,

I agree that it should...

>> but I just tested DPI with
>> connector_status_unknown (i.e. changed the above func to return unknown
>> for DPI

Good hint. I can do the same check. Maybe it highlights the real issue.

>> ), and it works fine with X and X omap driver. And xrandr
>> confirms that the connection status is unknown:
>>
>> # xrandr
>> Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 2048 x 2048
>> HDMI-1 disconnected (normal left inverted right x axis y axis)
>> None-1 unknown connection 1920x1200+0+0 (normal left inverted right x
>> axis y axis) 0mm x 0mm
>> 1920x1200 60.00*+ 60.00 +

Which configs, drivers and system are you using for this results?

>>
>> Grep also shows that there are many drivers using
>> connector_status_unknown, so I'm guessing it should work fine...
>
> And beside it's not right to consider VENC as always connected, as it isn't.

Hm. Well, the VENC (meaning the D/A converter inside the OMAP3 chip)
is always connected. But the monitor or cable isn't.

> The unknown status is there for a reason, to describe connectors for which we
> can't get any status information. The situation is different for DPI, DBI, SDI
> and DSI as those are on-board busses that connect to a non-removable panel, so
> we can say with a good confidence that the panel is connected (the situation
> could be changed with a hammer and a chisel, but that's unlikely to happen,
> hence the confidence).

Well, it may be that the omapdrm and X11 combination (unfortuantely I don't
understand either and have not found a good description how they interwork),
keeps the VENC disabled if the connector is unknown.

And since there is no code to detect that a cable has been connected, there
might be missing some trigger to enable the interface.

The symptom I see is that the status of this card is "disabled" while the LCD
panel is "enabled". After doing my proposed patch, both come up "enabled".

So my patch appears to be a work around some other still hidden problem.

Any hint from the experts how to debug / find the real issue & solution is welcome.

BR,
Nikolaus

2015-11-13 16:45:40

by H. Nikolaus Schaller

[permalink] [raw]
Subject: Re: [PATCH 2/2] video:omapdrm: make omapdrm assume the tv-out cable is always connected

Here the test results:

Am 13.11.2015 um 13:01 schrieb Laurent Pinchart <[email protected]>:

> On Friday 13 November 2015 13:46:01 Tomi Valkeinen wrote:
>> On 13/11/15 12:29, H. Nikolaus Schaller wrote:
>>> Include VENC in the set of drivers where it is assimed that the cable
>>> is always connected. Like DPI, DSI, DBI and SDI do.
>>>
>>> Otherwise, the VENC will return cable status "unknown" and is not enabled
>>> by the X-server. So there is no video output signal.
>>>
>>> Tested on: BeagleBoard XM, GTA04 and OpenPandora
>>>
>>> Signed-off-by: H. Nikolaus Schaller <[email protected]>
>>> ---
>>>
>>> drivers/gpu/drm/omapdrm/omap_connector.c | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/drivers/gpu/drm/omapdrm/omap_connector.c
>>> b/drivers/gpu/drm/omapdrm/omap_connector.c index 83f2a91..98ddb5d 100644
>>> --- a/drivers/gpu/drm/omapdrm/omap_connector.c
>>> +++ b/drivers/gpu/drm/omapdrm/omap_connector.c
>>> @@ -120,6 +120,7 @@ static enum drm_connector_status
>>> omap_connector_detect(
>>> else
>>> ret = connector_status_disconnected;
>>> } else if (dssdev->type == OMAP_DISPLAY_TYPE_DPI ||
>>> + dssdev->type == OMAP_DISPLAY_TYPE_VENC ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_DBI ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_SDI ||
>>> dssdev->type == OMAP_DISPLAY_TYPE_DSI) {
>>
>> I have no idea why VENC is not working for you when using
>> connector_status_unknown, but I just tested DPI with
>> connector_status_unknown (i.e. changed the above func to return unknown
>> for DPI), and it works fine with X and X omap driver. And xrandr
>> confirms that the connection status is unknown:
>>
>> # xrandr
>> Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 2048 x 2048
>> HDMI-1 disconnected (normal left inverted right x axis y axis)
>> None-1 unknown connection 1920x1200+0+0 (normal left inverted right x
>> axis y axis) 0mm x 0mm
>> 1920x1200 60.00*+ 60.00 +

A) with this VENC patch:

root@letux:~# xrandr
Screen 0: minimum 320 x 200, current 720 x 640, maximum 2048 x 2048
None-1 connected 720x574+0+0 0mm x 0mm
720x574i 50.00*+
None-2 connected 480x640+0+0 0mm x 0mm
480x640 65.74*+
root@letux:~# cat /sys/class/drm/card0-Unknown-*/enabled
enabled
enabled
root@letux:~# cat /sys/class/drm/card0-Unknown-*/status
connected
connected

B) w/o VENC patch (VENC returns returning connector_status_unknown):

root@letux:~# xrandr
Screen 0: minimum 320 x 200, current 480 x 640, maximum 2048 x 2048
None-1 connected 480x640+0+0 0mm x 0mm
480x640 65.74*+
None-2 unknown connection
720x574i 50.00 +
root@letux:~# cat /sys/class/drm/card0-Unknown-*/enabled
enabled
disabled
root@letux:~# cat /sys/class/drm/card0-Unknown-*/status
connected
unknown

C) with DPI (also) returning connector_status_unknown

root@letux:~# xrandr
Screen 0: minimum 320 x 200, current 720 x 640, maximum 2048 x 2048
None-1 unknown connection 720x574+0+0 0mm x 0mm
720x574i 50.00*+
None-2 unknown connection 480x640+0+0 0mm x 0mm
480x640 65.74*+
root@letux:~# cat /sys/class/drm/card0-Unknown-*/enabled
enabled
enabled
root@letux:~# cat /sys/class/drm/card0-Unknown-*/status
unknown
unknown
root@letux:~#

D) VENC patch but DPI returning connector_status_unknown

rroot@letux:~# xrandr
Screen 0: minimum 320 x 200, current 720 x 574, maximum 2048 x 2048
None-1 unknown connection
480x640 65.74 +
None-2 connected 720x574+0+0 0mm x 0mm
720x574i 50.00*+oot@letux:~# cat /sys/class/drm/card0-Unknown-*/enabled
disabled
enabled
root@letux:~# cat /sys/class/drm/card0-Unknown-*/status
unknown
connected

In case B) I have no TV out and in case D) I have no LCD.

So it looks as if it works if my LCD and VENC report the same
connection status. And fails if they differ.

Anyone with an explanation or even vague idea where to search
for the real bug?

BR and thanks,
Nikolaus

2015-12-09 08:18:51

by Tomi Valkeinen

[permalink] [raw]
Subject: Re: [PATCH 1/2] video:omap2:dss: fix timings for VENC to match what omapdrm expects


On 13/11/15 12:29, H. Nikolaus Schaller wrote:
> Otherwise check_timings fails and we get a "has no modes" message
> from xrandr.
>
> This fix makes the venc assume PAL and NTSC timings that match the
> timings synthetized by copy_timings_drm_to_omap() from omapdrm
> mode settings so that check_timings() succeeds.
>
> Tested on: BeagleBoard XM, GTA04 and OpenPandora
>
> Signed-off-by: H. Nikolaus Schaller <[email protected]>
> ---
> drivers/video/fbdev/omap2/dss/venc.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)

I've picked this up.

With this patch and the one below I can get tv-out working on my very old
beagleboard, and it seems to work with X also. It doesn't start automatically
as the connection state is unknown, but doing "xrandr --output None-1 --auto"
was all I needed to enable it.

Tomi

From a4274600a5a67256b91266b0d2624b9c9028909b Mon Sep 17 00:00:00 2001
From: Tomi Valkeinen <[email protected]>
Date: Tue, 8 Dec 2015 18:32:14 +0200
Subject: [PATCH] drm/omap: fix fbdev pix format to support all platforms

omap_fbdev always creates a framebuffer with ARGB8888 pixel format. On
OMAP3 we have VIDEO1 overlay that does not support ARGB8888, and on
OMAP2 none of the overlays support ARGB888.

This patch changes the omap_fbdev's fb to XRGB8888, which is supported
by all platforms.

Signed-off-by: Tomi Valkeinen <[email protected]>

diff --git a/drivers/gpu/drm/omapdrm/omap_fbdev.c b/drivers/gpu/drm/omapdrm/omap_fbdev.c
index b8e4cdec28c3..24f92bea39c7 100644
--- a/drivers/gpu/drm/omapdrm/omap_fbdev.c
+++ b/drivers/gpu/drm/omapdrm/omap_fbdev.c
@@ -112,11 +112,8 @@ static int omap_fbdev_create(struct drm_fb_helper *helper,
dma_addr_t paddr;
int ret;

- /* only doing ARGB32 since this is what is needed to alpha-blend
- * with video overlays:
- */
sizes->surface_bpp = 32;
- sizes->surface_depth = 32;
+ sizes->surface_depth = 24;

DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
sizes->surface_height, sizes->surface_bpp,


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2015-12-13 18:41:39

by H. Nikolaus Schaller

[permalink] [raw]
Subject: Re: [PATCH 1/2] video:omap2:dss: fix timings for VENC to match what omapdrm expects

Hi Tomi,

Am 09.12.2015 um 09:18 schrieb Tomi Valkeinen <[email protected]>:

>
> On 13/11/15 12:29, H. Nikolaus Schaller wrote:
>> Otherwise check_timings fails and we get a "has no modes" message
>> from xrandr.
>>
>> This fix makes the venc assume PAL and NTSC timings that match the
>> timings synthetized by copy_timings_drm_to_omap() from omapdrm
>> mode settings so that check_timings() succeeds.
>>
>> Tested on: BeagleBoard XM, GTA04 and OpenPandora
>>
>> Signed-off-by: H. Nikolaus Schaller <[email protected]>
>> ---
>> drivers/video/fbdev/omap2/dss/venc.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>
> I've picked this up.

Thanks!

>
> With this patch and the one below I can get tv-out working on my very old
> beagleboard, and it seems to work with X also. It doesn't start automatically
> as the connection state is unknown, but doing "xrandr --output None-1 --auto"
> was all I needed to enable it.

Great that you did find the real reason of the problem.

I have tested it on the GTA04 and it also works.

Will the patches arrive in 4.5?

So thanks a lot,
Nikolaus

>
> Tomi
>
> From a4274600a5a67256b91266b0d2624b9c9028909b Mon Sep 17 00:00:00 2001
> From: Tomi Valkeinen <[email protected]>
> Date: Tue, 8 Dec 2015 18:32:14 +0200
> Subject: [PATCH] drm/omap: fix fbdev pix format to support all platforms
>
> omap_fbdev always creates a framebuffer with ARGB8888 pixel format. On
> OMAP3 we have VIDEO1 overlay that does not support ARGB8888, and on
> OMAP2 none of the overlays support ARGB888.
>
> This patch changes the omap_fbdev's fb to XRGB8888, which is supported
> by all platforms.
>
> Signed-off-by: Tomi Valkeinen <[email protected]>
>
> diff --git a/drivers/gpu/drm/omapdrm/omap_fbdev.c b/drivers/gpu/drm/omapdrm/omap_fbdev.c
> index b8e4cdec28c3..24f92bea39c7 100644
> --- a/drivers/gpu/drm/omapdrm/omap_fbdev.c
> +++ b/drivers/gpu/drm/omapdrm/omap_fbdev.c
> @@ -112,11 +112,8 @@ static int omap_fbdev_create(struct drm_fb_helper *helper,
> dma_addr_t paddr;
> int ret;
>
> - /* only doing ARGB32 since this is what is needed to alpha-blend
> - * with video overlays:
> - */
> sizes->surface_bpp = 32;
> - sizes->surface_depth = 32;
> + sizes->surface_depth = 24;
>
> DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
> sizes->surface_height, sizes->surface_bpp,
>

2015-12-15 12:53:47

by Tomi Valkeinen

[permalink] [raw]
Subject: Re: [PATCH 1/2] video:omap2:dss: fix timings for VENC to match what omapdrm expects


On 13/12/15 20:41, H. Nikolaus Schaller wrote:

> Great that you did find the real reason of the problem.
>
> I have tested it on the GTA04 and it also works.
>
> Will the patches arrive in 4.5?

4.4, I hope.

Tomi


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