[PATCH v2 4/9] fixup! drm/xe/display: Implement display support

["Jouni Högander" <jouni.hogander@intel.com>]

We need to add i915_gem_object_read_from_page to build intel_display.c.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
---
 .../compat-i915-headers/gem/i915_gem_object.h | 31 +++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h b/drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h
index b991069b5cb3..eaab536f465f 100644
--- a/drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/xe/compat-i915-headers/gem/i915_gem_object.h
@@ -17,4 +17,35 @@ static inline dma_addr_t i915_gem_object_get_dma_address(const struct xe_bo *bo,
 	return n;
 }
 
+static inline int i915_gem_object_read_from_page(struct xe_bo *bo,
+					  u32 ofs, u64 *ptr, u32 size)
+{
+	struct ttm_bo_kmap_obj map;
+	void *virtual;
+	bool is_iomem;
+	int ret;
+
+	XE_WARN_ON(size != 8);
+
+	ret = xe_bo_lock(bo, true);
+	if (ret)
+		return ret;
+
+	ret = ttm_bo_kmap(&bo->ttm, ofs >> PAGE_SHIFT, 1, &map);
+	if (ret)
+		goto out_unlock;
+
+	ofs &= ~PAGE_MASK;
+	virtual = ttm_kmap_obj_virtual(&map, &is_iomem);
+	if (is_iomem)
+		*ptr = readq((void __iomem *)(virtual + ofs));
+	else
+		*ptr = *(u64 *)(virtual + ofs);
+
+	ttm_bo_kunmap(&map);
+out_unlock:
+	xe_bo_unlock(bo);
+	return ret;
+}
+
 #endif
-- 
2.34.1