drm/amdgpu/gfx9: simplify and fix GRBM index selection

Copy the approach taken by gfx8, which simplifies the code, and set the
instance index properly. The latter is required for debugging, e.g. for
reading wave status by UMR.

Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c

@@ -1475,21 +1475,23 @@ static void gfx_v9_0_tiling_mode_table_init(struct amdgpu_device *adev)
 
 static void gfx_v9_0_select_se_sh(struct amdgpu_device *adev, u32 se_num, u32 sh_num, u32 instance)
 {
-	u32 data = REG_SET_FIELD(0, GRBM_GFX_INDEX, INSTANCE_BROADCAST_WRITES, 1);
+	u32 data;
 
-	if ((se_num == 0xffffffff) && (sh_num == 0xffffffff)) {
-		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SH_BROADCAST_WRITES, 1);
-		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SE_BROADCAST_WRITES, 1);
-	} else if (se_num == 0xffffffff) {
-		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SH_INDEX, sh_num);
+	if (instance == 0xffffffff)
+		data = REG_SET_FIELD(0, GRBM_GFX_INDEX, INSTANCE_BROADCAST_WRITES, 1);
+	else
+		data = REG_SET_FIELD(0, GRBM_GFX_INDEX, INSTANCE_INDEX, instance);
+
+	if (se_num == 0xffffffff)
 		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SE_BROADCAST_WRITES, 1);
-	} else if (sh_num == 0xffffffff) {
-		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SH_BROADCAST_WRITES, 1);
+	else
 		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SE_INDEX, se_num);
-	} else {
+
+	if (sh_num == 0xffffffff)
+		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SH_BROADCAST_WRITES, 1);
+	else
 		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SH_INDEX, sh_num);
-		data = REG_SET_FIELD(data, GRBM_GFX_INDEX, SE_INDEX, se_num);
-	}
+
 	WREG32_SOC15(GC, 0, mmGRBM_GFX_INDEX, data);
 }