glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Alexey Brodkin]

Hello,

Being in the middle of bring-up of the new board with Vivante GPU (HSDK namely,
see?https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arc/plat-hsdk)
I was looking at simple 3D test apps to see how Etnaviv works on the hardware.

So far I was able to get kmscube working perfectly fine and the next item I took
was glxgears (for some reason I was under impression that's de facto "Hello world" app
in the GPU world). But apparently even with Xserver up and running glxgears doesn't work.

Moreover I tried the same thing on Wandboard Quad but to no avail as well.
That's what I saw:
------------------------->8---------------------
# glxgears
Error: couldn't get an RGB, Double-buffered visual

# glxinfo
name of display: :0
Error: couldn't find RGB GLX visual or fbconfig?
------------------------->8---------------------

Googling didn't help here unfortunately so maybe some pointers could be
suggested here... like what do I do wrong and if glxgears is supposed to
work on top of DRM GPU at all?

Thanks a lot in advance!

-Alexey

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Lucas Stach]

Hi Alexey,

Am Freitag, den 24.11.2017, 16:02 +0000 schrieb Alexey Brodkin:
> Hello,
> 
> Being in the middle of bring-up of the new board with Vivante GPU (HSDK namely,
> see?https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arc/plat-hsdk)
> I was looking at simple 3D test apps to see how Etnaviv works on the hardware.
> 
> So far I was able to get kmscube working perfectly fine and the next item I took
> was glxgears (for some reason I was under impression that's de facto "Hello world" app
> in the GPU world). But apparently even with Xserver up and running glxgears doesn't work.
> 
> Moreover I tried the same thing on Wandboard Quad but to no avail as well.
> That's what I saw:
> ------------------------->8---------------------
> # glxgears
> Error: couldn't get an RGB, Double-buffered visual
> 
> # glxinfo
> name of display: :0
> Error: couldn't find RGB GLX visual or fbconfig?
> ------------------------->8---------------------
> 
> Googling didn't help here unfortunately so maybe some pointers could be
> suggested here... like what do I do wrong and if glxgears is supposed to
> work on top of DRM GPU at all?
> 
> Thanks a lot in advance!

For 3D acceleration to work under X you need the etnaviv specific DDX
driver, which can be found here:

http://git.arm.linux.org.uk/cgit/xf86-video-armada.git/log/?h=unstable-devel

Don't let you get confused by the name, the armada driver implements
support for both armada drm and imx-drm and the etnaviv DDX. This
provides 2D acceleration on the Vivante 2D cores, as well a the DRI2/3
bit necessary to get a 3D context on X.

Regards,
Lucas

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Alexey Brodkin]

Hi Lucas,

On Fri, 2017-11-24@17:11 +0100, Lucas Stach wrote:
> Hi Alexey,
> 
> Am Freitag, den 24.11.2017, 16:02 +0000 schrieb Alexey Brodkin:
> > 
> > Hello,
> > 
> > Being in the middle of bring-up of the new board with Vivante GPU (HSDK namely,
> > see?https://urldefense.proofpoint.com/v2/url?u=https-3A__git.kernel.org_pub_scm_linux_kernel_git_torvalds_linux.git_tree_arch_arc_plat-2Dhsdk&d=Dw
> > IDaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> > bLY&s=ZJSI1u6GgsRHNIcONVFfIKvn1AWaB38GmtCN1dGB3w0&e=)
> > I was looking at simple 3D test apps to see how Etnaviv works on the hardware.
> > 
> > So far I was able to get kmscube working perfectly fine and the next item I took
> > was glxgears (for some reason I was under impression that's de facto "Hello world" app
> > in the GPU world). But apparently even with Xserver up and running glxgears doesn't work.
> > 
> > Moreover I tried the same thing on Wandboard Quad but to no avail as well.
> > That's what I saw:
> > ------------------------->8---------------------
> > # glxgears
> > Error: couldn't get an RGB, Double-buffered visual
> > 
> > # glxinfo
> > name of display: :0
> > Error: couldn't find RGB GLX visual or fbconfig?
> > ------------------------->8---------------------
> > 
> > Googling didn't help here unfortunately so maybe some pointers could be
> > suggested here... like what do I do wrong and if glxgears is supposed to
> > work on top of DRM GPU at all?
> > 
> > Thanks a lot in advance!
> 
> For 3D acceleration to work under X you need the etnaviv specific DDX
> driver, which can be found here:
> 
> https://urldefense.proofpoint.com/v2/url?u=http-3A__git.arm.linux.org.uk_cgit_xf86-2Dvideo-2Darmada.git_log_-3Fh-3Dunstable-2Ddevel&d=DwIDaQ&c=DPL6_
> X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> bLY&s=ZzK2fxA6_XlN6pGnf2Tpo6qKzzQh76ocWZ6IDR-WPtc&e=

Thanks for the pointer, still a couple of questions below...

> Don't let you get confused by the name, the armada driver implements
> support for both armada drm and imx-drm and the etnaviv DDX. This
> provides 2D acceleration on the Vivante 2D cores, as well a the DRI2/3
> bit necessary to get a 3D context on X.

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Lucas Stach]

Am Freitag, den 24.11.2017, 16:25 +0000 schrieb Alexey Brodkin:
> Hi Lucas,
> 
> On Fri, 2017-11-24@17:11 +0100, Lucas Stach wrote:
> > Hi Alexey,
> > 
> > Am Freitag, den 24.11.2017, 16:02 +0000 schrieb Alexey Brodkin:
> > > 
> > > Hello,
> > > 
> > > Being in the middle of bring-up of the new board with Vivante GPU (HSDK namely,
> > > see?https://urldefense.proofpoint.com/v2/url?u=https-3A__git.kernel.org_pub_scm_linux_kernel_git_torvalds_linux.git_tree_arch_arc_plat-2Dhsdk&d=Dw
> > > IDaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> > > bLY&s=ZJSI1u6GgsRHNIcONVFfIKvn1AWaB38GmtCN1dGB3w0&e=)
> > > I was looking at simple 3D test apps to see how Etnaviv works on the hardware.
> > > 
> > > So far I was able to get kmscube working perfectly fine and the next item I took
> > > was glxgears (for some reason I was under impression that's de facto "Hello world" app
> > > in the GPU world). But apparently even with Xserver up and running glxgears doesn't work.
> > > 
> > > Moreover I tried the same thing on Wandboard Quad but to no avail as well.
> > > That's what I saw:
> > > ------------------------->8---------------------
> > > # glxgears
> > > Error: couldn't get an RGB, Double-buffered visual
> > > 
> > > # glxinfo
> > > name of display: :0
> > > Error: couldn't find RGB GLX visual or fbconfig?
> > > ------------------------->8---------------------
> > > 
> > > Googling didn't help here unfortunately so maybe some pointers could be
> > > suggested here... like what do I do wrong and if glxgears is supposed to
> > > work on top of DRM GPU at all?
> > > 
> > > Thanks a lot in advance!
> > 
> > For 3D acceleration to work under X you need the etnaviv specific DDX
> > driver, which can be found here:
> > 
> > https://urldefense.proofpoint.com/v2/url?u=http-3A__git.arm.linux.org.uk_cgit_xf86-2Dvideo-2Darmada.git_log_-3Fh-3Dunstable-2Ddevel&d=DwIDaQ&c=DPL6_
> > X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> > bLY&s=ZzK2fxA6_XlN6pGnf2Tpo6qKzzQh76ocWZ6IDR-WPtc&e=
> 
> Thanks for the pointer, still a couple of questions below...
> 
> > Don't let you get confused by the name, the armada driver implements
> > support for both armada drm and imx-drm and the etnaviv DDX. This
> > provides 2D acceleration on the Vivante 2D cores, as well a the DRI2/3
> > bit necessary to get a 3D context on X.
> 
> From Wandboard's .dts I see that 2D core is a separate node with separate
> set of registers mapped at a different location in memory, right?
> 
> Do you know if that's possible if the same one memory-mapped register set
> controls both 3D and 2D engine?

Yes, a "core" in Vivante speak is a GPU with one DMA frontend. A single
frontend can feed both 3D and 2D acceleration engines behind it. On
i.MX6 the 2D and 3D engine are on separate cores, but Marvell Dove has
a combined 2D/3D core.

> If we happen to not have 2D core if that's a no go for us for anything?

I don't know if the DDX works properly without 2D acceleration. Weston
on the other hand only relies on the 3D accel core for doing
compositing, so even if you don't have a 2D engine you will be able to
launch a modern Linux graphics stack.

The etnaviv DDX could also emulate 2D accel over the 3D core by using
the X.Org glamor module, but no one has bothered to implement this yet.

> 
> In the meantime I'll try to figure out if we have 2D core or not.

You can find out what your GPU provides by looking at the feature bits.
chipFeatures_PIPE_2D, chipFeatures_PIPE_3D and chipFeatures_PIPE_VG is
what you are looking out for.

Regards,
Lucas

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Alexey Brodkin]

Hi Lucas,

On Fri, 2017-11-24@17:38 +0100, Lucas Stach wrote:
> Am Freitag, den 24.11.2017, 16:25 +0000 schrieb Alexey Brodkin:
> > 
> > Hi Lucas,
> > 
> > On Fri, 2017-11-24@17:11 +0100, Lucas Stach wrote:
> > > 
> > > Hi Alexey,
> > > 
> > > Am Freitag, den 24.11.2017, 16:02 +0000 schrieb Alexey Brodkin:
> > > > 
> > > > 
> > > > Hello,
> > > > 
> > > > Being in the middle of bring-up of the new board with Vivante GPU (HSDK namely,
> > > > see?https://urldefense.proofpoint.com/v2/url?u=https-3A__git.kernel.org_pub_scm_linux_kernel_git_torvalds_linux.git_tree_arch_arc_plat-2Dhsdk&
> > > > d=Dw
> > > > IDaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> > > > bLY&s=ZJSI1u6GgsRHNIcONVFfIKvn1AWaB38GmtCN1dGB3w0&e=)
> > > > I was looking at simple 3D test apps to see how Etnaviv works on the hardware.
> > > > 
> > > > So far I was able to get kmscube working perfectly fine and the next item I took
> > > > was glxgears (for some reason I was under impression that's de facto "Hello world" app
> > > > in the GPU world). But apparently even with Xserver up and running glxgears doesn't work.
> > > > 
> > > > Moreover I tried the same thing on Wandboard Quad but to no avail as well.
> > > > That's what I saw:
> > > > ------------------------->8---------------------
> > > > # glxgears
> > > > Error: couldn't get an RGB, Double-buffered visual
> > > > 
> > > > # glxinfo
> > > > name of display: :0
> > > > Error: couldn't find RGB GLX visual or fbconfig?
> > > > ------------------------->8---------------------
> > > > 
> > > > Googling didn't help here unfortunately so maybe some pointers could be
> > > > suggested here... like what do I do wrong and if glxgears is supposed to
> > > > work on top of DRM GPU at all?
> > > > 
> > > > Thanks a lot in advance!
> > > 
> > > For 3D acceleration to work under X you need the etnaviv specific DDX
> > > driver, which can be found here:
> > > 
> > > https://urldefense.proofpoint.com/v2/url?u=http-3A__git.arm.linux.org.uk_cgit_xf86-2Dvideo-2Darmada.git_log_-3Fh-3Dunstable-2Ddevel&d=DwIDaQ&c=D
> > > PL6_
> > > X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=ZXa-564Jm43PXsqGXCf2US2DY7C0qIlCw6c56pL-
> > > bLY&s=ZzK2fxA6_XlN6pGnf2Tpo6qKzzQh76ocWZ6IDR-WPtc&e=
> > 
> > Thanks for the pointer, still a couple of questions below...
> > 
> > > 
> > > Don't let you get confused by the name, the armada driver implements
> > > support for both armada drm and imx-drm and the etnaviv DDX. This
> > > provides 2D acceleration on the Vivante 2D cores, as well a the DRI2/3
> > > bit necessary to get a 3D context on X.
> > 
> > From Wandboard's .dts I see that 2D core is a separate node with separate
> > set of registers mapped at a different location in memory, right?
> > 
> > Do you know if that's possible if the same one memory-mapped register set
> > controls both 3D and 2D engine?
> 
> Yes, a "core" in Vivante speak is a GPU with one DMA frontend. A single
> frontend can feed both 3D and 2D acceleration engines behind it. On
> i.MX6 the 2D and 3D engine are on separate cores, but Marvell Dove has
> a combined 2D/3D core.

Hm, that sounds encouraging. The next question would be if Marvel Dove is
supported in Etnaviv DDX? I guess it's called Armada so the answer if yes, right?

> > If we happen to not have 2D core if that's a no go for us for anything?
> 
> I don't know if the DDX works properly without 2D acceleration. Weston
> on the other hand only relies on the 3D accel core for doing
> compositing, so even if you don't have a 2D engine you will be able to
> launch a modern Linux graphics stack.

That's really cool! I'm much more interested in Weston ATM, which is
actually another separate question :)
I tried to find some details on how to run Weston on Wandboard
but seems like I was looking at wrong Google again... do you
know any good manuals for doing that?

> 
> The etnaviv DDX could also emulate 2D accel over the 3D core by using
> the X.Org glamor module, but no one has bothered to implement this yet.

Ok we'll see if above case (combined cores) is applicable to us and then
we'll see what to do.

> > In the meantime I'll try to figure out if we have 2D core or not.
> 
> You can find out what your GPU provides by looking at the feature bits.
> chipFeatures_PIPE_2D, chipFeatures_PIPE_3D and chipFeatures_PIPE_VG is
> what you are looking out for.

Does that info helps to decipher these bits?
-------------------------->8------------------------------
# dmesg | grep etnaviv
etnaviv soc:gpu-subsystem: bound f0090000.gpu (ops 0x9075271c)
etnaviv-gpu f0090000.gpu: model: GC880, revision: 5124
[drm] Initialized etnaviv 1.1.0 20151214 for soc:gpu-subsystem on minor 0

# cat /sys/kernel/debug/dri/0/gpu?
f0090000.gpu Status:
????????features
?????????minor_features0: 0x41f99efb
?????????minor_features1: 0xfefbf2d9
?????????minor_features2: 0x4a180285
?????????minor_features3: 0x00000001
?????????minor_features4: 0x00000000
?????????minor_features5: 0x00020000
????????specs
?????????stream_count:??8
?????????register_max: 64
?????????thread_count: 256
?????????vertex_cache_size: 8
?????????shader_core_count: 1
?????????pixel_pipes: 1
?????????vertex_output_buffer_size: 512
?????????buffer_size: 0
?????????instruction_count: 512
?????????num_constants: 576
?????????varyings_count: 12
????????axi: 0x00000050
????????idle: 0x7ffffffe
?????????FE is not idle
????????DMA address is constant
?????????address 0: 0x00000000
?????????address 1: 0x00000000
?????????state 0: 0x00000000
?????????state 1: 0x00000800
?????????last fetch 64 bit word: 0x40000002 0x00000000
-------------------------->8------------------------------

-Alexey

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Lucas Stach]

Am Freitag, den 24.11.2017, 16:49 +0000 schrieb Alexey Brodkin:
[...]
> > Yes, a "core" in Vivante speak is a GPU with one DMA frontend. A
> > single
> > frontend can feed both 3D and 2D acceleration engines behind it. On
> > i.MX6 the 2D and 3D engine are on separate cores, but Marvell Dove
> > has
> > a combined 2D/3D core.
> 
> Hm, that sounds encouraging. The next question would be if Marvel
> Dove is
> supported in Etnaviv DDX? I guess it's called Armada so the answer if
> yes, right?

Yes, the Dove was the original platform for the Armada X.Org driver.
Combined 2D/3D cores are supported just fine by etnaviv.

> > > If we happen to not have 2D core if that's a no go for us for
> > > anything?
> > 
> > I don't know if the DDX works properly without 2D acceleration.
> > Weston
> > on the other hand only relies on the 3D accel core for doing
> > compositing, so even if you don't have a 2D engine you will be able
> > to
> > launch a modern Linux graphics stack.
> 
> That's really cool! I'm much more interested in Weston ATM, which is
> actually another separate question :)
> I tried to find some details on how to run Weston on Wandboard
> but seems like I was looking at wrong Google again... do you
> know any good manuals for doing that?

There really is no magic to it. Or better there is, but it's all hidden
in the Mesa implementation.

You need at least Mesa 17.2 and Weston 3.0 for etnaviv to work
properly. Other than that just set XDG_RUNTIME_DIR to something
sensible and launch Weston with "weston --tty=63", done.

> > 
> > The etnaviv DDX could also emulate 2D accel over the 3D core by
> > using
> > the X.Org glamor module, but no one has bothered to implement this
> > yet.
> 
> Ok we'll see if above case (combined cores) is applicable to us and
> then
> we'll see what to do.
> 
> > > In the meantime I'll try to figure out if we have 2D core or not.
> > 
> > You can find out what your GPU provides by looking at the feature
> > bits.
> > chipFeatures_PIPE_2D, chipFeatures_PIPE_3D and chipFeatures_PIPE_VG
> > is
> > what you are looking out for.
> 
> Does that info helps to decipher these bits?

Unfortunately we forgot to expose the major feature bits register in
debugfs. It's gpu->identity.features in the kernel driver, the
interesting bits in there are chipFeatures_PIPE_3D and
chipFeatures_PIPE_2D.

Regards,
Lucas

glxgears on Etnaviv: couldn't get an RGB, Double-buffered visual

[Alexey Brodkin]

Hi Lucas,

On Fri, 2017-11-24@18:11 +0100, Lucas Stach wrote:
> Am Freitag, den 24.11.2017, 16:49 +0000 schrieb Alexey Brodkin:
> [...]
> > 
> > > 
> > > Yes, a "core" in Vivante speak is a GPU with one DMA frontend. A
> > > single
> > > frontend can feed both 3D and 2D acceleration engines behind it. On
> > > i.MX6 the 2D and 3D engine are on separate cores, but Marvell Dove
> > > has
> > > a combined 2D/3D core.
> > 
> > Hm, that sounds encouraging. The next question would be if Marvel
> > Dove is
> > supported in Etnaviv DDX? I guess it's called Armada so the answer if
> > yes, right?
> 
> Yes, the Dove was the original platform for the Armada X.Org driver.
> Combined 2D/3D cores are supported just fine by etnaviv.

Sweet!
Maybe another question then.
To get kmscube working on our board which uses essentially different
bit-streamer device "udl" as opposed to "imx-drm" I had just to say:
---------------------->8----------------------
export MESA_LOADER_DRIVER_OVERRIDE=imx-drm
---------------------->8----------------------
and then all the magic has happened.

Will it be
?a) required
?b) enough
for Vivante X.org driver?

> > > > If we happen to not have 2D core if that's a no go for us for
> > > > anything?
> > > 
> > > I don't know if the DDX works properly without 2D acceleration.
> > > Weston
> > > on the other hand only relies on the 3D accel core for doing
> > > compositing, so even if you don't have a 2D engine you will be able
> > > to
> > > launch a modern Linux graphics stack.
> > 
> > That's really cool! I'm much more interested in Weston ATM, which is
> > actually another separate question :)
> > I tried to find some details on how to run Weston on Wandboard
> > but seems like I was looking at wrong Google again... do you
> > know any good manuals for doing that?
> 
> There really is no magic to it. Or better there is, but it's all hidden
> in the Mesa implementation.
> 
> You need at least Mesa 17.2 and Weston 3.0 for etnaviv to work
> properly. Other than that just set XDG_RUNTIME_DIR to something
> sensible and launch Weston with "weston --tty=63", done.

Cool, will try that!

> > > The etnaviv DDX could also emulate 2D accel over the 3D core by
> > > using
> > > the X.Org glamor module, but no one has bothered to implement this
> > > yet.
> > 
> > Ok we'll see if above case (combined cores) is applicable to us and
> > then
> > we'll see what to do.
> > 
> > > 
> > > > 
> > > > In the meantime I'll try to figure out if we have 2D core or not.
> > > 
> > > You can find out what your GPU provides by looking at the feature
> > > bits.
> > > chipFeatures_PIPE_2D, chipFeatures_PIPE_3D and chipFeatures_PIPE_VG
> > > is
> > > what you are looking out for.
> > 

> > Does that info helps to decipher these bits?
> 
> Unfortunately we forgot to expose the major feature bits register in
> debugfs. It's gpu->identity.features in the kernel driver, the
> interesting bits in there are chipFeatures_PIPE_3D and
> chipFeatures_PIPE_2D.

Noted!

Are you going to add that yourself sometime soon or shall I do it?

-Alexey