gcc: error: unrecognized command-line option '-mfp16-format=ieee'

[adam900710]

When compiling the code, gcc errors out for the option '-mfp16-format=ieee'.

Full output is attached. output.txt

The host system is ARM64 board (Nvidia Xavier AGX), running Manjaro ARM distro.

GCC version is 10.2.0.

[digetx]

Do you have any specific reason why you're building it for arm64? This driver isn't intended for Xavier, you need to use modesetting driver.

[adam900710]

No wonder.

But the problem is, if using modesetting for AGX, it just falls back to LLVMpipe, even the mesa package has gallium driver compiled for tegra.

Or do I need anything else to enable proper hardware accleration for AGX?

[adam900710]

Anyway, it's something unrelated to the package.

Closing.

[digetx]

You may need to use the most recent xorg server from git and even apply some extra patches. But I don't really know much about AGX, @cyndis and @thierryreding should know better.

[kwizart]

You need both tegra and nouveau gallium drivers enabled for mesa.

Also I wonder which kernel version are you using, I've experienced regressions with some recent kernel. upstream 5.10 is known good. (tested on jetson-tk1, but should be the same on arm64). It's possible that recent mainline has some fixes (or maybe linux-next).

[adam900710]

The mesa-git package I built has both nouveau and tegra gallium drivers enabled.

And the kernel I'm using is upstream v5.13 kernel, with CONFIG_DRM_TEGRA=m (or there should be no /dev/dri/card0).

Thus it's really strange Xorg just falls backto llvmpipe.

[kwizart]

I think you may also need CONFIG_DRM_TEGRA_STAGING=y (along CONFIG_DRM_NOUVEAU=m)

edit: and indeed, using xorg-server from development is mandatory. (unless using backported patches for drm modifiers support at least).

[cyndis]

Nouveau does not yet support the GV11B; only up to GP10B (on Tegra186).

[adam900710]

OK, the full xorg rebuild looks a little scary now.

xorg-server needs xorgproto >= 2.3.99.1, I'm not sure how the dependency chain will be.

Any idea which patches I need to backport? Or I should just wait for next xorg-server release?

[adam900710]

BTW, why mesa don't have a page for tegra in its platform/drivers page? https://docs.mesa3d.org/systems.html

Even panfrost/vc4 has their pages, while the strongest mobile GPU doesn't have one looks strange to me...

[digetx]

IIUC, the current stable Xorg doesn't support display modifiers which may be needed by latest Tegras. But since GV11B isn't supported by the Nouveau driver yet, then patching Xorg won't help anyways. You'll need to wait until support will be added.

The Nouveau is the main opensource GPU driver for T124+ SoCs. Mesa's Tegra driver only provides a small glue that links Nouveau with Tegra. It may be a good idea to have a dedicated Tegra wiki page that documents the current support status and provide links to WIP patches since the current staus isn't ideal. It's actually a very normal thing in opensource development to have a slow-pace upstream, nearly every tenth package in Gentoo has a dozen of extra patches with bugfixes and extra features.

[adam900710]

No problem waiting for the proper support in next xorg release.

Just no sure if I'm missing some config or had some wrong setting which makes me unable to try tegra drivers.

Thus a page for mesa wiki would really help guys like me.

(For the worst case, I can just plug a RX580 into the Xavier AGX board with extra PSU and call it a day)