[Intel-xe] [PATCH 7/7] drm/xe: Remove i915 header dependency when building without display

[Maarten Lankhorst]

Series looks good.

Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

On 2023-03-02 02:34, Lucas De Marchi wrote:
> If xe is built without support for driving display, it shouldn't need
> the i915 headers. As a consequence the build system shouldn't be passing
> the additional CFLAGS to include the i915 directories. However as the
> display structs were needed in other compilation units, it was not
> possible to remove, leading to every single file indirectly including
> the i915 headers via xe_device_types.h.
>
> The Makefile had a note about i915 register definitions, but missed the
> display dependencies.
>
> Now that the display substruct from xe_device and the info substruct
> from xe->info are initialized by display-only files, it's possible to
> shield the rest of the driver with some additional ifdefs. Ideally the
> structs should be made opaque and only defined in the display
> compilation units: this would allow removing the includes from
> xe_device_types.h even when building with display. However this needs
> more refactors and cleanups because the i915 files expect the info and
> display substruct to be available from drm_i915_private that is aliased
> by xe_device when building xe.  So, to avoid future dependencies on the
> i915 headers, just add a few more ifdefs in the header so a build
> without display breaks if this is attempted.
>
> Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
> ---
>   drivers/gpu/drm/xe/Makefile          | 3 ---
>   drivers/gpu/drm/xe/xe_device_types.h | 9 ++++++---
>   2 files changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index d1d255df74a1..5489d761f6f6 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -104,9 +104,6 @@ subdir-ccflags-$(CONFIG_DRM_XE_DISPLAY) += -I$(srctree)/$(src)/display/ext \
>   	-Ddrm_i915_gem_object=xe_bo \
>   	-Ddrm_i915_private=xe_device
>   
> -# XXX: Needed for i915 register definitions. Will be removed after xe-regs.
> -subdir-ccflags-y += -I$(srctree)/drivers/gpu/drm/i915/
> -
>   CFLAGS_display/intel_fbdev.o = $(call cc-disable-warning, override-init)
>   
>   $(obj)/display/i915_%.o: $(srctree)/drivers/gpu/drm/i915/display/i915_%.c FORCE
> diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
> index ec36cedb87cc..199bd37fce9a 100644
> --- a/drivers/gpu/drm/xe/xe_device_types.h
> +++ b/drivers/gpu/drm/xe/xe_device_types.h
> @@ -16,10 +16,11 @@
>   #include "xe_platform_types.h"
>   #include "xe_step_types.h"
>   
> -/* For display substruct */
> +#if IS_ENABLED(CONFIG_DRM_XE_DISPLAY)
>   #include "display/ext/intel_device_info.h"
>   #include "display/ext/intel_pch.h"
>   #include "display/intel_display_core.h"
> +#endif
>   
>   #define XE_BO_INVALID_OFFSET	LONG_MAX
>   
> @@ -97,6 +98,7 @@ struct xe_device {
>   		/** @enable_display: display enabled */
>   		bool enable_display;
>   
> +#if IS_ENABLED(CONFIG_DRM_XE_DISPLAY)
>   		struct xe_device_display_info {
>   			u8 ver;
>   
> @@ -147,6 +149,7 @@ struct xe_device {
>   			u8 num_scalers[I915_MAX_PIPES];
>   			u32 rawclk_freq;
>   		} display;
> +#endif
>   	} info;
>   
>   	/** @irq: device interrupt state */
> @@ -241,8 +244,7 @@ struct xe_device {
>   	/** @d3cold_allowed: Indicates if d3cold is a valid device state */
>   	bool d3cold_allowed;
>   
> -	/* private: */
> -
> +#if IS_ENABLED(CONFIG_DRM_XE_DISPLAY)
>   	/*
>   	 * Any fields below this point are the ones used by display.
>   	 * They are temporarily added here so xe_device can be desguised as
> @@ -308,6 +310,7 @@ struct xe_device {
>   		const char *vbt_firmware;
>   		u32 lvds_channel_mode;
>   	} params;
> +#endif
>   };
>   
>   /**