Re: [PATCH] drm/xe/dp: Enable DP tunneling

[Imre Deak <imre.deak@intel.com>]

On Thu, Jan 16, 2025 at 02:32:21PM -0600, Lucas De Marchi wrote:
> On Mon, Jan 13, 2025 at 05:48:32PM +0200, Imre Deak wrote:
> > Enable the DP tunneling functionality in the xe driver.
> > 
> > Signed-off-by: Imre Deak <imre.deak@intel.com>
> > ---
> > drivers/gpu/drm/i915/display/intel_dp_tunnel.h |  5 +++--
> > drivers/gpu/drm/xe/Kconfig                     | 14 ++++++++++++++
> > drivers/gpu/drm/xe/Makefile                    |  3 +++
> > 3 files changed, 20 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp_tunnel.h b/drivers/gpu/drm/i915/display/intel_dp_tunnel.h
> > index e9314cf25a193..7a91b4945eb8d 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp_tunnel.h
> > +++ b/drivers/gpu/drm/i915/display/intel_dp_tunnel.h
> > @@ -20,7 +20,8 @@ struct intel_dp;
> > struct intel_encoder;
> > struct intel_link_bw_limits;
> > 
> > -#if IS_ENABLED(CONFIG_DRM_I915_DP_TUNNEL) && defined(I915)
> > +#if (defined(CONFIG_DRM_I915_DP_TUNNEL) && defined(I915)) || \
> > +	(defined(CONFIG_DRM_XE_DP_TUNNEL) && !defined(I915))
> > 
> > int intel_dp_tunnel_detect(struct intel_dp *intel_dp, struct drm_modeset_acquire_ctx *ctx);
> > void intel_dp_tunnel_disconnect(struct intel_dp *intel_dp);
> > @@ -127,6 +128,6 @@ intel_dp_tunnel_mgr_init(struct intel_display *display)
> > 
> > static inline void intel_dp_tunnel_mgr_cleanup(struct intel_display *display) {}
> > 
> > -#endif /* CONFIG_DRM_I915_DP_TUNNEL */
> > +#endif /* CONFIG_DRM_I915_DP_TUNNEL || CONFIG_DRM_XE_DP_TUNNEL */
> > 
> > #endif /* __INTEL_DP_TUNNEL_H__ */
> > diff --git a/drivers/gpu/drm/xe/Kconfig b/drivers/gpu/drm/xe/Kconfig
> > index b51a2bde73e29..50cf80df51900 100644
> > --- a/drivers/gpu/drm/xe/Kconfig
> > +++ b/drivers/gpu/drm/xe/Kconfig
> > @@ -59,6 +59,20 @@ config DRM_XE_DISPLAY
> > 	help
> > 	  Disable this option only if you want to compile out display support.
> > 
> > +config DRM_XE_DP_TUNNEL
> > +	bool "Enable DP tunnel support"
> > +	depends on DRM_XE
> > +	depends on USB4
> > +	select DRM_DISPLAY_DP_TUNNEL
> > +	default y
> > +	help
> > +	  Choose this option to detect DP tunnels and enable the Bandwidth
> > +	  Allocation mode for such tunnels. This allows using the maximum
> > +	  resolution allowed by the link BW on all displays sharing the
> > +	  link BW, for instance on a Thunderbolt link.
> > +
> > +	  If in doubt say "Y".
> > +
> > config DRM_XE_FORCE_PROBE
> > 	string "Force probe xe for selected Intel hardware IDs"
> > 	depends on DRM_XE
> > diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> > index 5c97ad6ed7385..81f63258a7e19 100644
> > --- a/drivers/gpu/drm/xe/Makefile
> > +++ b/drivers/gpu/drm/xe/Makefile
> > @@ -301,6 +301,9 @@ ifeq ($(CONFIG_DEBUG_FS),y)
> > 		i915-display/intel_pipe_crc.o
> > endif
> > 
> > +xe-$(CONFIG_DRM_XE_DP_TUNNEL) += \
> > +	i915-display/intel_dp_tunnel.o
> 
> something looks wrong here. We shouldn't build anything in i915-display/ if
> we don't have DRM_XE_DISPLAY. Are you missing a
> 
> 	depends on XE_DISPLAY
> ?

Yes, thanks for spotting that, I missed the possibility for a
non-display build. Will follow up with a fix for this.

> and in fact, with the .config I get:
> 
> In file included from
> ../drivers/gpu/drm/i915/display/intel_display_core.h:23,
> from ../drivers/gpu/drm/i915/display/intel_dp_tunnel.c:9:
> ../drivers/gpu/drm/i915/display/intel_display_power.h:12:10: fatal error:
> intel_wakeref.h: No such file or directory       12 | #include
> "intel_wakeref.h"
> 
> because we don't setup the right include directories.
> We used to test in CI a display-disabled build, not sure what happened
> with that.
> 
> Lucas De Marchi
> 
> > +
> > obj-$(CONFIG_DRM_XE) += xe.o
> > obj-$(CONFIG_DRM_XE_KUNIT_TEST) += tests/
> > 
> > -- 
> > 2.44.2
> >