Crocus Gallium3D Adds Experimental Intel Gen8 Graphics, Overlapping With Iris Driver

[phoronix]

Phoronix: Crocus Gallium3D Adds Experimental Intel Gen8 Graphics, Overlapping With Iris Driver

Landing in mainline Mesa 21.2 development code last week was the "Crocus" Gallium3D driver for old Intel hardware spanning from the Intel 965 chipset days "Gen4" up through Crocus supporting Haswell "Gen7" graphics. The i965 to Haswell span has been the focus since the official Intel "Iris" Gallium3D driver already in Mesa supports the Broadwell "Gen8" up through all current Intel UHD/Xe Graphics. But now Crocus with the latest Mesa code has added Gen8 support...

https://www.phoronix.com/scan.php?page=news_item&px=Crocus-Gallium3D-Gen8

[Aryma]

i have several questions :

1. how did dev handle: https://dri.freedesktop.org/wiki/I965Todo/ and I965Errata in old driver
2. any plan for add stencil_texturing like they promised in I965 for IVB?
3. is it possible to add support in "IBC: A new Intel Back-end Compiler" to crocus ?
4. is A2B10G10R10/A2R10G10B10 or GL_RGB10_A2 format is working in the new driver?

[antonyshen]

Maybe someday the iris and crocus drive could merge into one driver set.

[sravn]

Maybe someday the iris and crocus drive could merge into one driver set.

The two drivers are made separate on purpose to ease maintenance. The ongoing work to move support for gen8 to crocus is to avoid any non-softpin GPU in iris to make iris simpler to maintain and extend.

[Quackdoc]

Iris does not handle cherryview processors. it doesn't overlap, but compliment each other

[smitty3268]

i have several questions:
how did dev handle: https://dri.freedesktop.org/wiki/I965Todo/ and I965Errata in old driver

I haven't reviewed the code, but this is essentially a straight port of code from Iris and the existing i965 driver. So it's possible that moving from i965 to gallium automatically provided some beneficial changes, but otherwise you can expect it to be exactly the same. No one has gone to a ton of extra effort to add new driver specific code except where it was required to get things working on par with the old driver.

is it possible to add support in "IBC: A new Intel Back-end Compiler" to crocus ?

That compiler only supports Skylake and newer architectures, so no.

[zboszor]

Iris does not handle cherryview processors. it doesn't overlap, but compliment each other

But Iris supports Broadwell and Crocus does, too, although with a limited feature set.
For Crocus you need an environment variable to claim a Broadwell device and it's for debugging purposes only.
So there is a small overlap here.