[Nouveau] [PATCH 2/3] drm/nouveau/kms/nv50-: Report max cursor size to userspace

[Uwe Sauter]

Hi Ilia,

Am 24.02.21 um 18:47 schrieb Ilia Mirkin:
> On Wed, Feb 24, 2021 at 12:03 PM Alex Riesen
> <alexander.riesen at cetitec.com> wrote:
>>
>> Ilia Mirkin, Wed, Feb 24, 2021 17:57:41 +0100:
>>> On Wed, Feb 24, 2021 at 11:53 AM Alex Riesen <alexander.riesen at cetitec.com> wrote:
>>>> Ilia Mirkin, Wed, Feb 24, 2021 17:48:39 +0100:
>>>>> Just to be crystal clear -- are you saying that 128x128 works or does
>>>>> not work? (You said "yes", which would imply it works OK, but then you
>>>>> said both cases, which would imply doesn't work since 256x256 doesn't
>>>>> work?)
>>>>
>>>> Modetest with 128x128 cursor works. Without damage to the cursor: modetest
>>>> shows normal cursor in vanilla v5.11. Modetest also shows normal cursor in
>>>> vanilla v5.11 with the commit reverted.
>>>
>>> But modetest with 256x256 doesn't work (correctly) right? Or did I
>>> misunderstand?
>>
>> Right. That's why I was asking if I did everything right: it was just corrupted
>> in both kernels.
> 
> OK. So 128x128 works, 256x256 does not. Interesting.
> 
>>
>>> All the patch does is allow those large cursors to be used, which gets
>>> reported via drm APIs and modesetting picks the largest cursor
>>> available. (And actually I think it's even not required to use the
>>> large cursors, it just controls what's reported in the defaults to
>>> userspace.)
>>
>> Maybe something in X code is not prepared to handle the kernel reporting
>> large cursor support? Even though 128x128 is pretty large, and I don't think
>> I even use that large cursors in X configuration. How can I check?
> 
> Yes, 64x64 is enough for anyone (or was it 640kb?) But it's unlikely
> to be an issue. I believe that AMD also exposes 256x256 cursors
> depending on the gen:
> 
> display/dc/dce100/dce100_resource.c:    dc->caps.max_cursor_size = 128;
> display/dc/dce110/dce110_resource.c:    dc->caps.max_cursor_size = 128;
> display/dc/dce112/dce112_resource.c:    dc->caps.max_cursor_size = 128;
> display/dc/dce120/dce120_resource.c:    dc->caps.max_cursor_size = 128;
> display/dc/dce60/dce60_resource.c:      dc->caps.max_cursor_size = 64;
> display/dc/dce60/dce60_resource.c:      dc->caps.max_cursor_size = 64;
> display/dc/dce60/dce60_resource.c:      dc->caps.max_cursor_size = 64;
> display/dc/dce80/dce80_resource.c:      dc->caps.max_cursor_size = 128;
> display/dc/dce80/dce80_resource.c:      dc->caps.max_cursor_size = 128;
> display/dc/dce80/dce80_resource.c:      dc->caps.max_cursor_size = 128;
> display/dc/dcn10/dcn10_resource.c:      dc->caps.max_cursor_size = 256;
> display/dc/dcn20/dcn20_resource.c:      dc->caps.max_cursor_size = 256;
> display/dc/dcn21/dcn21_resource.c:      dc->caps.max_cursor_size = 256;
> display/dc/dcn30/dcn30_resource.c:      dc->caps.max_cursor_size = 256;
> 
> which should have the equivalent effect.
> 
> But since you're seeing issues with modetest as well (which uses the
> ioctl's pretty directly), presumably Xorg is not to blame.
> 
> It's easy enough to adjust the kernel to report a lower size (and
> reject the larger cursors), I just want to understand which gens are
> affected by this.

I can also report that the modesetting ddx that comes with xorg-server 1.20.10-3 (Arch Linux package) shows this kind of 
cursor-cut-into-horizontal-stripes behavior. Changing to xf86-video-nouveau 1.0.17-1 solves this issue. But nouveau has 
issues with Mate 1.24 (as discussed earlier this month).

My hardware:
# lspci -s 3:0.0 -v
03:00.0 VGA compatible controller: NVIDIA Corporation GK208B [GeForce GT 710] (rev a1) (prog-if 00 [VGA controller])
	Subsystem: ASUSTeK Computer Inc. GT710-4H-SL-2GD5
	Flags: bus master, fast devsel, latency 0, IRQ 36, IOMMU group 12
	Memory at fb000000 (32-bit, non-prefetchable) [size=16M]
	Memory at fff0000000 (64-bit, prefetchable) [size=128M]
	Memory at fff8000000 (64-bit, prefetchable) [size=32M]
	I/O ports at f000 [size=128]
	Expansion ROM at fc000000 [disabled] [size=512K]
	Capabilities: [60] Power Management version 3
	Capabilities: [68] MSI: Enable+ Count=1/1 Maskable- 64bit+
	Capabilities: [78] Express Legacy Endpoint, MSI 00
	Capabilities: [100] Virtual Channel
	Capabilities: [128] Power Budgeting <?>
	Capabilities: [600] Vendor Specific Information: ID=0001 Rev=1 Len=024 <?>
	Capabilities: [900] Secondary PCI Express
	Kernel driver in use: nouveau
	Kernel modules: nouveau


If I can help in any way please let me know.

Regards,

	Uwe




> Cheers,
> 
>    -ilia
> _______________________________________________
> Nouveau mailing list
> Nouveau at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/nouveau
>