drm/xe/bmg: Add BMG platform definition

BMG is a discrete GPU based on the Xe2 architecture.
No device ids are bound to the BMG platform descriptor yet.
BMG device ids will be added once we have all the basic required
platform enabling patches landed.

v2: Removed device ids, deferring it to a later patch

v3: Squash in compat header IS_BATTLEMAGE() patch.  (Lucas)

Bspec: 68090
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240408170545.3769566-4-balasubramani.vivekanandan@intel.com

drivers/gpu/drm/xe/compat-i915-headers/i915_drv.h

@@ -90,6 +90,7 @@ static inline struct drm_i915_private *kdev_to_i915(struct device *kdev)
 #define IS_PONTEVECCHIO(dev_priv) IS_PLATFORM(dev_priv, XE_PVC)
 #define IS_METEORLAKE(dev_priv) IS_PLATFORM(dev_priv, XE_METEORLAKE)
 #define IS_LUNARLAKE(dev_priv) IS_PLATFORM(dev_priv, XE_LUNARLAKE)
+#define IS_BATTLEMAGE(dev_priv)  IS_PLATFORM(dev_priv, XE_BATTLEMAGE)
 
 #define IS_HASWELL_ULT(dev_priv) (dev_priv && 0)
 #define IS_BROADWELL_ULT(dev_priv) (dev_priv && 0)

drivers/gpu/drm/xe/xe_pci.c

@@ -336,6 +336,12 @@ static const struct xe_device_desc lnl_desc = {
 	.require_force_probe = true,
 };
 
+static const struct xe_device_desc bmg_desc __maybe_unused = {
+	DGFX_FEATURES,
+	PLATFORM(XE_BATTLEMAGE),
+	.require_force_probe = true,
+};
+
 #undef PLATFORM
 __diag_pop();
 

drivers/gpu/drm/xe/xe_platform_types.h

@@ -22,6 +22,7 @@ enum xe_platform {
 	XE_PVC,
 	XE_METEORLAKE,
 	XE_LUNARLAKE,
+	XE_BATTLEMAGE,
 };
 
 enum xe_subplatform {