[PATCH 3/5] drm/xe: Helper to get dpa from pfn

[Oak Zeng <oak.zeng@intel.com>]

Since we now create struct page backing for each vram page,
each vram page now also has a pfn, just like system memory.
This allow us to calcuate device physical address from pfn.

Signed-off-by: Oak Zeng <oak.zeng@intel.com>
---
 drivers/gpu/drm/xe/xe_device_types.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
index bbea40b57e84..bf349321f037 100644
--- a/drivers/gpu/drm/xe/xe_device_types.h
+++ b/drivers/gpu/drm/xe/xe_device_types.h
@@ -576,4 +576,12 @@ static inline struct xe_tile *mem_region_to_tile(struct xe_mem_region *mr)
 	return container_of(mr, struct xe_tile, mem.vram);
 }
 
+static inline u64 vram_pfn_to_dpa(struct xe_mem_region *mr, u64 pfn)
+{
+	u64 dpa;
+	u64 offset = (pfn << PAGE_SHIFT) - mr->hpa_base;
+	dpa = mr->dpa_base + offset;
+	return dpa;
+}
+
 #endif
-- 
2.26.3