[PATCH v3 1/2] drm/amdgpu: Adding db_size to get doorbell absolute offset

[Arvind Yadav]

Here, passing db_size in byte to find the doorbell's
absolute offset for both 32-bit and 64-bit doorbell sizes.
So that doorbell offset will be aligned based on the doorbell
size.

v3:
- Adding db_size as parameter to get db absolute offset.

Cc: Christian Koenig <christian.koenig@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Shashank Sharma <shashank.sharma@xxxxxxx>
Signed-off-by: Arvind Yadav <Arvind.Yadav@xxxxxxx>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h     |  5 +++--
 drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c | 13 +++++++++----
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
index 09f6727e7c73..4a8b33f55f6b 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
@@ -357,8 +357,9 @@ int amdgpu_doorbell_init(struct amdgpu_device *adev);
 void amdgpu_doorbell_fini(struct amdgpu_device *adev);
 int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device *adev);
 uint32_t amdgpu_doorbell_index_on_bar(struct amdgpu_device *adev,
-				       struct amdgpu_bo *db_bo,
-				       uint32_t doorbell_index);
+				      struct amdgpu_bo *db_bo,
+				      uint32_t doorbell_index,
+				      uint32_t db_size);
 
 #define RDOORBELL32(index) amdgpu_mm_rdoorbell(adev, (index))
 #define WDOORBELL32(index, v) amdgpu_mm_wdoorbell(adev, (index), (v))
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
index da4be0bbb446..6690f5a72f4d 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
@@ -114,19 +114,24 @@ void amdgpu_mm_wdoorbell64(struct amdgpu_device *adev, u32 index, u64 v)
  * @adev: amdgpu_device pointer
  * @db_bo: doorbell object's bo
  * @db_index: doorbell relative index in this doorbell object
+ * @db_size: doorbell size is in byte
  *
  * returns doorbell's absolute index in BAR
  */
 uint32_t amdgpu_doorbell_index_on_bar(struct amdgpu_device *adev,
-				       struct amdgpu_bo *db_bo,
-				       uint32_t doorbell_index)
+				      struct amdgpu_bo *db_bo,
+				      uint32_t doorbell_index,
+				      uint32_t db_size)
 {
 	int db_bo_offset;
 
 	db_bo_offset = amdgpu_bo_gpu_offset_no_check(db_bo);
 
-	/* doorbell index is 32 bit but doorbell's size is 64-bit, so *2 */
-	return db_bo_offset / sizeof(u32) + doorbell_index * 2;
+	/* doorbell index is 32 bit but doorbell's size can be 32 bit
+	 * or 64 bit, so *db_size(in byte)/4 for alignment.
+	 */
+	return db_bo_offset / sizeof(u32) + doorbell_index *
+	       DIV_ROUND_UP(db_size, 4);
 }
 
 /**
-- 
2.34.1