Re: modesetting vs intel in 10.0

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

Brian Stuart <blstuart%gmail.com@localhost> wrote:
> Am I correct that even with all the improvements, there are still
> Intel video systems that aren't supported?  On a Dell Latitude 7420,
> dmesg shows:
>
> [     1.051227] pchb0 at pci0 dev 0 function 0: Intel Tiger Lake (UP3
> 4Core) Host (rev. 0x01)
> [     1.051227] i915drmkms: preliminary hardware support disabled

The NetBSD driver code tests the require_force_probe member of the
pci_device_id struct, it prints the message above and doesnt attach the
DRM driver if it is set.

This is set for Elkhart Lake and Tiger Lake GPUs in the version of the
DRM code in the tree, which is from Linux 5.6-rc3, later GPUs are not
detected at all.

The equivalent Linux probe function doesn't do very much if this flag
is set, you could try just removing the test to see what happens using
the patch below.

If people have got the i915drmkms driver to attach then it would be
helpful if they could try the new native MesaLib, I don't have any
recent Intel systems to test it on. To build new MesaLib set
HAVE_MESA_VER=21 in your /etc/mk.conf before running build.sh.

Index: i915_pci_autoconf.c
===================================================================
RCS file: /cvsroot/src/sys/external/bsd/drm2/i915drm/i915_pci_autoconf.c,v
retrieving revision 1.14
diff -u -r1.14 i915_pci_autoconf.c
--- i915_pci_autoconf.c 15 Oct 2022 15:20:06 -0000      1.14
+++ i915_pci_autoconf.c 29 Aug 2023 12:55:27 -0000
@@ -108,11 +108,12 @@
        const struct intel_device_info *const info =
            (struct intel_device_info *)ent->driver_data;
 
+#if 0
        if (info->require_force_probe) {
                printf("i915drmkms: preliminary hardware support disabled\n");
                return NULL;
        }
-
+#endif
        return ent;
 }